xref: /linux/net/ipv6/addrconf.c (revision 66a0e2d579dbec5c676cfe446234ffebb267c564)
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 static inline s32 rfc3315_s14_backoff_init(s32 irt)
116 {
117 	/* multiply 'initial retransmission time' by 0.9 .. 1.1 */
118 	u64 tmp = (900000 + prandom_u32() % 200001) * (u64)irt;
119 	do_div(tmp, 1000000);
120 	return (s32)tmp;
121 }
122 
123 static inline s32 rfc3315_s14_backoff_update(s32 rt, s32 mrt)
124 {
125 	/* multiply 'retransmission timeout' by 1.9 .. 2.1 */
126 	u64 tmp = (1900000 + prandom_u32() % 200001) * (u64)rt;
127 	do_div(tmp, 1000000);
128 	if ((s32)tmp > mrt) {
129 		/* multiply 'maximum retransmission time' by 0.9 .. 1.1 */
130 		tmp = (900000 + prandom_u32() % 200001) * (u64)mrt;
131 		do_div(tmp, 1000000);
132 	}
133 	return (s32)tmp;
134 }
135 
136 #ifdef CONFIG_SYSCTL
137 static int addrconf_sysctl_register(struct inet6_dev *idev);
138 static void addrconf_sysctl_unregister(struct inet6_dev *idev);
139 #else
140 static inline int addrconf_sysctl_register(struct inet6_dev *idev)
141 {
142 	return 0;
143 }
144 
145 static inline void addrconf_sysctl_unregister(struct inet6_dev *idev)
146 {
147 }
148 #endif
149 
150 static void ipv6_regen_rndid(struct inet6_dev *idev);
151 static void ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr);
152 
153 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev);
154 static int ipv6_count_addresses(struct inet6_dev *idev);
155 static int ipv6_generate_stable_address(struct in6_addr *addr,
156 					u8 dad_count,
157 					const struct inet6_dev *idev);
158 
159 /*
160  *	Configured unicast address hash table
161  */
162 static struct hlist_head inet6_addr_lst[IN6_ADDR_HSIZE];
163 static DEFINE_SPINLOCK(addrconf_hash_lock);
164 
165 static void addrconf_verify(void);
166 static void addrconf_verify_rtnl(void);
167 static void addrconf_verify_work(struct work_struct *);
168 
169 static struct workqueue_struct *addrconf_wq;
170 static DECLARE_DELAYED_WORK(addr_chk_work, addrconf_verify_work);
171 
172 static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
173 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
174 
175 static void addrconf_type_change(struct net_device *dev,
176 				 unsigned long event);
177 static int addrconf_ifdown(struct net_device *dev, int how);
178 
179 static struct rt6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
180 						  int plen,
181 						  const struct net_device *dev,
182 						  u32 flags, u32 noflags);
183 
184 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
185 static void addrconf_dad_work(struct work_struct *w);
186 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id);
187 static void addrconf_dad_run(struct inet6_dev *idev);
188 static void addrconf_rs_timer(unsigned long data);
189 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
190 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
191 
192 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
193 				struct prefix_info *pinfo);
194 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
195 			       struct net_device *dev);
196 
197 static struct ipv6_devconf ipv6_devconf __read_mostly = {
198 	.forwarding		= 0,
199 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
200 	.mtu6			= IPV6_MIN_MTU,
201 	.accept_ra		= 1,
202 	.accept_redirects	= 1,
203 	.autoconf		= 1,
204 	.force_mld_version	= 0,
205 	.mldv1_unsolicited_report_interval = 10 * HZ,
206 	.mldv2_unsolicited_report_interval = HZ,
207 	.dad_transmits		= 1,
208 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
209 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
210 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
211 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
212 	.use_tempaddr		= 0,
213 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
214 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
215 	.regen_max_retry	= REGEN_MAX_RETRY,
216 	.max_desync_factor	= MAX_DESYNC_FACTOR,
217 	.max_addresses		= IPV6_MAX_ADDRESSES,
218 	.accept_ra_defrtr	= 1,
219 	.accept_ra_from_local	= 0,
220 	.accept_ra_min_hop_limit= 1,
221 	.accept_ra_pinfo	= 1,
222 #ifdef CONFIG_IPV6_ROUTER_PREF
223 	.accept_ra_rtr_pref	= 1,
224 	.rtr_probe_interval	= 60 * HZ,
225 #ifdef CONFIG_IPV6_ROUTE_INFO
226 	.accept_ra_rt_info_max_plen = 0,
227 #endif
228 #endif
229 	.proxy_ndp		= 0,
230 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
231 	.disable_ipv6		= 0,
232 	.accept_dad		= 1,
233 	.suppress_frag_ndisc	= 1,
234 	.accept_ra_mtu		= 1,
235 	.stable_secret		= {
236 		.initialized = false,
237 	},
238 	.use_oif_addrs_only	= 0,
239 	.ignore_routes_with_linkdown = 0,
240 	.keep_addr_on_down	= 0,
241 	.seg6_enabled		= 0,
242 #ifdef CONFIG_IPV6_SEG6_HMAC
243 	.seg6_require_hmac	= 0,
244 #endif
245 	.enhanced_dad           = 1,
246 };
247 
248 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
249 	.forwarding		= 0,
250 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
251 	.mtu6			= IPV6_MIN_MTU,
252 	.accept_ra		= 1,
253 	.accept_redirects	= 1,
254 	.autoconf		= 1,
255 	.force_mld_version	= 0,
256 	.mldv1_unsolicited_report_interval = 10 * HZ,
257 	.mldv2_unsolicited_report_interval = HZ,
258 	.dad_transmits		= 1,
259 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
260 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
261 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
262 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
263 	.use_tempaddr		= 0,
264 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
265 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
266 	.regen_max_retry	= REGEN_MAX_RETRY,
267 	.max_desync_factor	= MAX_DESYNC_FACTOR,
268 	.max_addresses		= IPV6_MAX_ADDRESSES,
269 	.accept_ra_defrtr	= 1,
270 	.accept_ra_from_local	= 0,
271 	.accept_ra_min_hop_limit= 1,
272 	.accept_ra_pinfo	= 1,
273 #ifdef CONFIG_IPV6_ROUTER_PREF
274 	.accept_ra_rtr_pref	= 1,
275 	.rtr_probe_interval	= 60 * HZ,
276 #ifdef CONFIG_IPV6_ROUTE_INFO
277 	.accept_ra_rt_info_max_plen = 0,
278 #endif
279 #endif
280 	.proxy_ndp		= 0,
281 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
282 	.disable_ipv6		= 0,
283 	.accept_dad		= 1,
284 	.suppress_frag_ndisc	= 1,
285 	.accept_ra_mtu		= 1,
286 	.stable_secret		= {
287 		.initialized = false,
288 	},
289 	.use_oif_addrs_only	= 0,
290 	.ignore_routes_with_linkdown = 0,
291 	.keep_addr_on_down	= 0,
292 	.seg6_enabled		= 0,
293 #ifdef CONFIG_IPV6_SEG6_HMAC
294 	.seg6_require_hmac	= 0,
295 #endif
296 	.enhanced_dad           = 1,
297 };
298 
299 /* Check if a valid qdisc is available */
300 static inline bool addrconf_qdisc_ok(const struct net_device *dev)
301 {
302 	return !qdisc_tx_is_noop(dev);
303 }
304 
305 static void addrconf_del_rs_timer(struct inet6_dev *idev)
306 {
307 	if (del_timer(&idev->rs_timer))
308 		__in6_dev_put(idev);
309 }
310 
311 static void addrconf_del_dad_work(struct inet6_ifaddr *ifp)
312 {
313 	if (cancel_delayed_work(&ifp->dad_work))
314 		__in6_ifa_put(ifp);
315 }
316 
317 static void addrconf_mod_rs_timer(struct inet6_dev *idev,
318 				  unsigned long when)
319 {
320 	if (!timer_pending(&idev->rs_timer))
321 		in6_dev_hold(idev);
322 	mod_timer(&idev->rs_timer, jiffies + when);
323 }
324 
325 static void addrconf_mod_dad_work(struct inet6_ifaddr *ifp,
326 				   unsigned long delay)
327 {
328 	if (!delayed_work_pending(&ifp->dad_work))
329 		in6_ifa_hold(ifp);
330 	mod_delayed_work(addrconf_wq, &ifp->dad_work, delay);
331 }
332 
333 static int snmp6_alloc_dev(struct inet6_dev *idev)
334 {
335 	int i;
336 
337 	idev->stats.ipv6 = alloc_percpu(struct ipstats_mib);
338 	if (!idev->stats.ipv6)
339 		goto err_ip;
340 
341 	for_each_possible_cpu(i) {
342 		struct ipstats_mib *addrconf_stats;
343 		addrconf_stats = per_cpu_ptr(idev->stats.ipv6, i);
344 		u64_stats_init(&addrconf_stats->syncp);
345 	}
346 
347 
348 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
349 					GFP_KERNEL);
350 	if (!idev->stats.icmpv6dev)
351 		goto err_icmp;
352 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
353 					   GFP_KERNEL);
354 	if (!idev->stats.icmpv6msgdev)
355 		goto err_icmpmsg;
356 
357 	return 0;
358 
359 err_icmpmsg:
360 	kfree(idev->stats.icmpv6dev);
361 err_icmp:
362 	free_percpu(idev->stats.ipv6);
363 err_ip:
364 	return -ENOMEM;
365 }
366 
367 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
368 {
369 	struct inet6_dev *ndev;
370 	int err = -ENOMEM;
371 
372 	ASSERT_RTNL();
373 
374 	if (dev->mtu < IPV6_MIN_MTU)
375 		return ERR_PTR(-EINVAL);
376 
377 	ndev = kzalloc(sizeof(struct inet6_dev), GFP_KERNEL);
378 	if (!ndev)
379 		return ERR_PTR(err);
380 
381 	rwlock_init(&ndev->lock);
382 	ndev->dev = dev;
383 	INIT_LIST_HEAD(&ndev->addr_list);
384 	setup_timer(&ndev->rs_timer, addrconf_rs_timer,
385 		    (unsigned long)ndev);
386 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
387 
388 	if (ndev->cnf.stable_secret.initialized)
389 		ndev->addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
390 	else
391 		ndev->addr_gen_mode = IN6_ADDR_GEN_MODE_EUI64;
392 
393 	ndev->cnf.mtu6 = dev->mtu;
394 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
395 	if (!ndev->nd_parms) {
396 		kfree(ndev);
397 		return ERR_PTR(err);
398 	}
399 	if (ndev->cnf.forwarding)
400 		dev_disable_lro(dev);
401 	/* We refer to the device */
402 	dev_hold(dev);
403 
404 	if (snmp6_alloc_dev(ndev) < 0) {
405 		ADBG(KERN_WARNING
406 			"%s: cannot allocate memory for statistics; dev=%s.\n",
407 			__func__, dev->name);
408 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
409 		dev_put(dev);
410 		kfree(ndev);
411 		return ERR_PTR(err);
412 	}
413 
414 	if (snmp6_register_dev(ndev) < 0) {
415 		ADBG(KERN_WARNING
416 			"%s: cannot create /proc/net/dev_snmp6/%s\n",
417 			__func__, dev->name);
418 		goto err_release;
419 	}
420 
421 	/* One reference from device. */
422 	in6_dev_hold(ndev);
423 
424 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
425 		ndev->cnf.accept_dad = -1;
426 
427 #if IS_ENABLED(CONFIG_IPV6_SIT)
428 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
429 		pr_info("%s: Disabled Multicast RS\n", dev->name);
430 		ndev->cnf.rtr_solicits = 0;
431 	}
432 #endif
433 
434 	INIT_LIST_HEAD(&ndev->tempaddr_list);
435 	ndev->desync_factor = U32_MAX;
436 	if ((dev->flags&IFF_LOOPBACK) ||
437 	    dev->type == ARPHRD_TUNNEL ||
438 	    dev->type == ARPHRD_TUNNEL6 ||
439 	    dev->type == ARPHRD_SIT ||
440 	    dev->type == ARPHRD_NONE) {
441 		ndev->cnf.use_tempaddr = -1;
442 	} else
443 		ipv6_regen_rndid(ndev);
444 
445 	ndev->token = in6addr_any;
446 
447 	if (netif_running(dev) && addrconf_qdisc_ok(dev))
448 		ndev->if_flags |= IF_READY;
449 
450 	ipv6_mc_init_dev(ndev);
451 	ndev->tstamp = jiffies;
452 	err = addrconf_sysctl_register(ndev);
453 	if (err) {
454 		ipv6_mc_destroy_dev(ndev);
455 		snmp6_unregister_dev(ndev);
456 		goto err_release;
457 	}
458 	/* protected by rtnl_lock */
459 	rcu_assign_pointer(dev->ip6_ptr, ndev);
460 
461 	/* Join interface-local all-node multicast group */
462 	ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes);
463 
464 	/* Join all-node multicast group */
465 	ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
466 
467 	/* Join all-router multicast group if forwarding is set */
468 	if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
469 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
470 
471 	return ndev;
472 
473 err_release:
474 	neigh_parms_release(&nd_tbl, ndev->nd_parms);
475 	ndev->dead = 1;
476 	in6_dev_finish_destroy(ndev);
477 	return ERR_PTR(err);
478 }
479 
480 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
481 {
482 	struct inet6_dev *idev;
483 
484 	ASSERT_RTNL();
485 
486 	idev = __in6_dev_get(dev);
487 	if (!idev) {
488 		idev = ipv6_add_dev(dev);
489 		if (IS_ERR(idev))
490 			return NULL;
491 	}
492 
493 	if (dev->flags&IFF_UP)
494 		ipv6_mc_up(idev);
495 	return idev;
496 }
497 
498 static int inet6_netconf_msgsize_devconf(int type)
499 {
500 	int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
501 		    + nla_total_size(4);	/* NETCONFA_IFINDEX */
502 	bool all = false;
503 
504 	if (type == NETCONFA_ALL)
505 		all = true;
506 
507 	if (all || type == NETCONFA_FORWARDING)
508 		size += nla_total_size(4);
509 #ifdef CONFIG_IPV6_MROUTE
510 	if (all || type == NETCONFA_MC_FORWARDING)
511 		size += nla_total_size(4);
512 #endif
513 	if (all || type == NETCONFA_PROXY_NEIGH)
514 		size += nla_total_size(4);
515 
516 	if (all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN)
517 		size += nla_total_size(4);
518 
519 	return size;
520 }
521 
522 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
523 				      struct ipv6_devconf *devconf, u32 portid,
524 				      u32 seq, int event, unsigned int flags,
525 				      int type)
526 {
527 	struct nlmsghdr  *nlh;
528 	struct netconfmsg *ncm;
529 	bool all = false;
530 
531 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
532 			flags);
533 	if (!nlh)
534 		return -EMSGSIZE;
535 
536 	if (type == NETCONFA_ALL)
537 		all = true;
538 
539 	ncm = nlmsg_data(nlh);
540 	ncm->ncm_family = AF_INET6;
541 
542 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
543 		goto nla_put_failure;
544 
545 	if ((all || type == NETCONFA_FORWARDING) &&
546 	    nla_put_s32(skb, NETCONFA_FORWARDING, devconf->forwarding) < 0)
547 		goto nla_put_failure;
548 #ifdef CONFIG_IPV6_MROUTE
549 	if ((all || type == NETCONFA_MC_FORWARDING) &&
550 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
551 			devconf->mc_forwarding) < 0)
552 		goto nla_put_failure;
553 #endif
554 	if ((all || type == NETCONFA_PROXY_NEIGH) &&
555 	    nla_put_s32(skb, NETCONFA_PROXY_NEIGH, devconf->proxy_ndp) < 0)
556 		goto nla_put_failure;
557 
558 	if ((all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN) &&
559 	    nla_put_s32(skb, NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
560 			devconf->ignore_routes_with_linkdown) < 0)
561 		goto nla_put_failure;
562 
563 	nlmsg_end(skb, nlh);
564 	return 0;
565 
566 nla_put_failure:
567 	nlmsg_cancel(skb, nlh);
568 	return -EMSGSIZE;
569 }
570 
571 void inet6_netconf_notify_devconf(struct net *net, int type, int ifindex,
572 				  struct ipv6_devconf *devconf)
573 {
574 	struct sk_buff *skb;
575 	int err = -ENOBUFS;
576 
577 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_KERNEL);
578 	if (!skb)
579 		goto errout;
580 
581 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
582 					 RTM_NEWNETCONF, 0, type);
583 	if (err < 0) {
584 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
585 		WARN_ON(err == -EMSGSIZE);
586 		kfree_skb(skb);
587 		goto errout;
588 	}
589 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_KERNEL);
590 	return;
591 errout:
592 	rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
593 }
594 
595 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
596 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
597 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
598 	[NETCONFA_PROXY_NEIGH]	= { .len = sizeof(int) },
599 	[NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN]	= { .len = sizeof(int) },
600 };
601 
602 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
603 				     struct nlmsghdr *nlh)
604 {
605 	struct net *net = sock_net(in_skb->sk);
606 	struct nlattr *tb[NETCONFA_MAX+1];
607 	struct netconfmsg *ncm;
608 	struct sk_buff *skb;
609 	struct ipv6_devconf *devconf;
610 	struct inet6_dev *in6_dev;
611 	struct net_device *dev;
612 	int ifindex;
613 	int err;
614 
615 	err = nlmsg_parse(nlh, sizeof(*ncm), tb, NETCONFA_MAX,
616 			  devconf_ipv6_policy);
617 	if (err < 0)
618 		goto errout;
619 
620 	err = -EINVAL;
621 	if (!tb[NETCONFA_IFINDEX])
622 		goto errout;
623 
624 	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
625 	switch (ifindex) {
626 	case NETCONFA_IFINDEX_ALL:
627 		devconf = net->ipv6.devconf_all;
628 		break;
629 	case NETCONFA_IFINDEX_DEFAULT:
630 		devconf = net->ipv6.devconf_dflt;
631 		break;
632 	default:
633 		dev = __dev_get_by_index(net, ifindex);
634 		if (!dev)
635 			goto errout;
636 		in6_dev = __in6_dev_get(dev);
637 		if (!in6_dev)
638 			goto errout;
639 		devconf = &in6_dev->cnf;
640 		break;
641 	}
642 
643 	err = -ENOBUFS;
644 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(NETCONFA_ALL), GFP_ATOMIC);
645 	if (!skb)
646 		goto errout;
647 
648 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
649 					 NETLINK_CB(in_skb).portid,
650 					 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
651 					 NETCONFA_ALL);
652 	if (err < 0) {
653 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
654 		WARN_ON(err == -EMSGSIZE);
655 		kfree_skb(skb);
656 		goto errout;
657 	}
658 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
659 errout:
660 	return err;
661 }
662 
663 static int inet6_netconf_dump_devconf(struct sk_buff *skb,
664 				      struct netlink_callback *cb)
665 {
666 	struct net *net = sock_net(skb->sk);
667 	int h, s_h;
668 	int idx, s_idx;
669 	struct net_device *dev;
670 	struct inet6_dev *idev;
671 	struct hlist_head *head;
672 
673 	s_h = cb->args[0];
674 	s_idx = idx = cb->args[1];
675 
676 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
677 		idx = 0;
678 		head = &net->dev_index_head[h];
679 		rcu_read_lock();
680 		cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^
681 			  net->dev_base_seq;
682 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
683 			if (idx < s_idx)
684 				goto cont;
685 			idev = __in6_dev_get(dev);
686 			if (!idev)
687 				goto cont;
688 
689 			if (inet6_netconf_fill_devconf(skb, dev->ifindex,
690 						       &idev->cnf,
691 						       NETLINK_CB(cb->skb).portid,
692 						       cb->nlh->nlmsg_seq,
693 						       RTM_NEWNETCONF,
694 						       NLM_F_MULTI,
695 						       NETCONFA_ALL) < 0) {
696 				rcu_read_unlock();
697 				goto done;
698 			}
699 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
700 cont:
701 			idx++;
702 		}
703 		rcu_read_unlock();
704 	}
705 	if (h == NETDEV_HASHENTRIES) {
706 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
707 					       net->ipv6.devconf_all,
708 					       NETLINK_CB(cb->skb).portid,
709 					       cb->nlh->nlmsg_seq,
710 					       RTM_NEWNETCONF, NLM_F_MULTI,
711 					       NETCONFA_ALL) < 0)
712 			goto done;
713 		else
714 			h++;
715 	}
716 	if (h == NETDEV_HASHENTRIES + 1) {
717 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
718 					       net->ipv6.devconf_dflt,
719 					       NETLINK_CB(cb->skb).portid,
720 					       cb->nlh->nlmsg_seq,
721 					       RTM_NEWNETCONF, NLM_F_MULTI,
722 					       NETCONFA_ALL) < 0)
723 			goto done;
724 		else
725 			h++;
726 	}
727 done:
728 	cb->args[0] = h;
729 	cb->args[1] = idx;
730 
731 	return skb->len;
732 }
733 
734 #ifdef CONFIG_SYSCTL
735 static void dev_forward_change(struct inet6_dev *idev)
736 {
737 	struct net_device *dev;
738 	struct inet6_ifaddr *ifa;
739 
740 	if (!idev)
741 		return;
742 	dev = idev->dev;
743 	if (idev->cnf.forwarding)
744 		dev_disable_lro(dev);
745 	if (dev->flags & IFF_MULTICAST) {
746 		if (idev->cnf.forwarding) {
747 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
748 			ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
749 			ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters);
750 		} else {
751 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
752 			ipv6_dev_mc_dec(dev, &in6addr_interfacelocal_allrouters);
753 			ipv6_dev_mc_dec(dev, &in6addr_sitelocal_allrouters);
754 		}
755 	}
756 
757 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
758 		if (ifa->flags&IFA_F_TENTATIVE)
759 			continue;
760 		if (idev->cnf.forwarding)
761 			addrconf_join_anycast(ifa);
762 		else
763 			addrconf_leave_anycast(ifa);
764 	}
765 	inet6_netconf_notify_devconf(dev_net(dev), NETCONFA_FORWARDING,
766 				     dev->ifindex, &idev->cnf);
767 }
768 
769 
770 static void addrconf_forward_change(struct net *net, __s32 newf)
771 {
772 	struct net_device *dev;
773 	struct inet6_dev *idev;
774 
775 	for_each_netdev(net, dev) {
776 		idev = __in6_dev_get(dev);
777 		if (idev) {
778 			int changed = (!idev->cnf.forwarding) ^ (!newf);
779 			idev->cnf.forwarding = newf;
780 			if (changed)
781 				dev_forward_change(idev);
782 		}
783 	}
784 }
785 
786 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int newf)
787 {
788 	struct net *net;
789 	int old;
790 
791 	if (!rtnl_trylock())
792 		return restart_syscall();
793 
794 	net = (struct net *)table->extra2;
795 	old = *p;
796 	*p = newf;
797 
798 	if (p == &net->ipv6.devconf_dflt->forwarding) {
799 		if ((!newf) ^ (!old))
800 			inet6_netconf_notify_devconf(net, NETCONFA_FORWARDING,
801 						     NETCONFA_IFINDEX_DEFAULT,
802 						     net->ipv6.devconf_dflt);
803 		rtnl_unlock();
804 		return 0;
805 	}
806 
807 	if (p == &net->ipv6.devconf_all->forwarding) {
808 		int old_dflt = net->ipv6.devconf_dflt->forwarding;
809 
810 		net->ipv6.devconf_dflt->forwarding = newf;
811 		if ((!newf) ^ (!old_dflt))
812 			inet6_netconf_notify_devconf(net, NETCONFA_FORWARDING,
813 						     NETCONFA_IFINDEX_DEFAULT,
814 						     net->ipv6.devconf_dflt);
815 
816 		addrconf_forward_change(net, newf);
817 		if ((!newf) ^ (!old))
818 			inet6_netconf_notify_devconf(net, NETCONFA_FORWARDING,
819 						     NETCONFA_IFINDEX_ALL,
820 						     net->ipv6.devconf_all);
821 	} else if ((!newf) ^ (!old))
822 		dev_forward_change((struct inet6_dev *)table->extra1);
823 	rtnl_unlock();
824 
825 	if (newf)
826 		rt6_purge_dflt_routers(net);
827 	return 1;
828 }
829 
830 static void addrconf_linkdown_change(struct net *net, __s32 newf)
831 {
832 	struct net_device *dev;
833 	struct inet6_dev *idev;
834 
835 	for_each_netdev(net, dev) {
836 		idev = __in6_dev_get(dev);
837 		if (idev) {
838 			int changed = (!idev->cnf.ignore_routes_with_linkdown) ^ (!newf);
839 
840 			idev->cnf.ignore_routes_with_linkdown = newf;
841 			if (changed)
842 				inet6_netconf_notify_devconf(dev_net(dev),
843 							     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
844 							     dev->ifindex,
845 							     &idev->cnf);
846 		}
847 	}
848 }
849 
850 static int addrconf_fixup_linkdown(struct ctl_table *table, int *p, int newf)
851 {
852 	struct net *net;
853 	int old;
854 
855 	if (!rtnl_trylock())
856 		return restart_syscall();
857 
858 	net = (struct net *)table->extra2;
859 	old = *p;
860 	*p = newf;
861 
862 	if (p == &net->ipv6.devconf_dflt->ignore_routes_with_linkdown) {
863 		if ((!newf) ^ (!old))
864 			inet6_netconf_notify_devconf(net,
865 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
866 						     NETCONFA_IFINDEX_DEFAULT,
867 						     net->ipv6.devconf_dflt);
868 		rtnl_unlock();
869 		return 0;
870 	}
871 
872 	if (p == &net->ipv6.devconf_all->ignore_routes_with_linkdown) {
873 		net->ipv6.devconf_dflt->ignore_routes_with_linkdown = newf;
874 		addrconf_linkdown_change(net, newf);
875 		if ((!newf) ^ (!old))
876 			inet6_netconf_notify_devconf(net,
877 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
878 						     NETCONFA_IFINDEX_ALL,
879 						     net->ipv6.devconf_all);
880 	}
881 	rtnl_unlock();
882 
883 	return 1;
884 }
885 
886 #endif
887 
888 /* Nobody refers to this ifaddr, destroy it */
889 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
890 {
891 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
892 
893 #ifdef NET_REFCNT_DEBUG
894 	pr_debug("%s\n", __func__);
895 #endif
896 
897 	in6_dev_put(ifp->idev);
898 
899 	if (cancel_delayed_work(&ifp->dad_work))
900 		pr_notice("delayed DAD work was pending while freeing ifa=%p\n",
901 			  ifp);
902 
903 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
904 		pr_warn("Freeing alive inet6 address %p\n", ifp);
905 		return;
906 	}
907 	ip6_rt_put(ifp->rt);
908 
909 	kfree_rcu(ifp, rcu);
910 }
911 
912 static void
913 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
914 {
915 	struct list_head *p;
916 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
917 
918 	/*
919 	 * Each device address list is sorted in order of scope -
920 	 * global before linklocal.
921 	 */
922 	list_for_each(p, &idev->addr_list) {
923 		struct inet6_ifaddr *ifa
924 			= list_entry(p, struct inet6_ifaddr, if_list);
925 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
926 			break;
927 	}
928 
929 	list_add_tail(&ifp->if_list, p);
930 }
931 
932 static u32 inet6_addr_hash(const struct in6_addr *addr)
933 {
934 	return hash_32(ipv6_addr_hash(addr), IN6_ADDR_HSIZE_SHIFT);
935 }
936 
937 /* On success it returns ifp with increased reference count */
938 
939 static struct inet6_ifaddr *
940 ipv6_add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
941 	      const struct in6_addr *peer_addr, int pfxlen,
942 	      int scope, u32 flags, u32 valid_lft, u32 prefered_lft)
943 {
944 	struct inet6_ifaddr *ifa = NULL;
945 	struct rt6_info *rt;
946 	unsigned int hash;
947 	int err = 0;
948 	int addr_type = ipv6_addr_type(addr);
949 
950 	if (addr_type == IPV6_ADDR_ANY ||
951 	    addr_type & IPV6_ADDR_MULTICAST ||
952 	    (!(idev->dev->flags & IFF_LOOPBACK) &&
953 	     addr_type & IPV6_ADDR_LOOPBACK))
954 		return ERR_PTR(-EADDRNOTAVAIL);
955 
956 	rcu_read_lock_bh();
957 	if (idev->dead) {
958 		err = -ENODEV;			/*XXX*/
959 		goto out2;
960 	}
961 
962 	if (idev->cnf.disable_ipv6) {
963 		err = -EACCES;
964 		goto out2;
965 	}
966 
967 	spin_lock(&addrconf_hash_lock);
968 
969 	/* Ignore adding duplicate addresses on an interface */
970 	if (ipv6_chk_same_addr(dev_net(idev->dev), addr, idev->dev)) {
971 		ADBG("ipv6_add_addr: already assigned\n");
972 		err = -EEXIST;
973 		goto out;
974 	}
975 
976 	ifa = kzalloc(sizeof(struct inet6_ifaddr), GFP_ATOMIC);
977 
978 	if (!ifa) {
979 		ADBG("ipv6_add_addr: malloc failed\n");
980 		err = -ENOBUFS;
981 		goto out;
982 	}
983 
984 	rt = addrconf_dst_alloc(idev, addr, false);
985 	if (IS_ERR(rt)) {
986 		err = PTR_ERR(rt);
987 		goto out;
988 	}
989 
990 	neigh_parms_data_state_setall(idev->nd_parms);
991 
992 	ifa->addr = *addr;
993 	if (peer_addr)
994 		ifa->peer_addr = *peer_addr;
995 
996 	spin_lock_init(&ifa->lock);
997 	INIT_DELAYED_WORK(&ifa->dad_work, addrconf_dad_work);
998 	INIT_HLIST_NODE(&ifa->addr_lst);
999 	ifa->scope = scope;
1000 	ifa->prefix_len = pfxlen;
1001 	ifa->flags = flags | IFA_F_TENTATIVE;
1002 	ifa->valid_lft = valid_lft;
1003 	ifa->prefered_lft = prefered_lft;
1004 	ifa->cstamp = ifa->tstamp = jiffies;
1005 	ifa->tokenized = false;
1006 
1007 	ifa->rt = rt;
1008 
1009 	ifa->idev = idev;
1010 	in6_dev_hold(idev);
1011 	/* For caller */
1012 	in6_ifa_hold(ifa);
1013 
1014 	/* Add to big hash table */
1015 	hash = inet6_addr_hash(addr);
1016 
1017 	hlist_add_head_rcu(&ifa->addr_lst, &inet6_addr_lst[hash]);
1018 	spin_unlock(&addrconf_hash_lock);
1019 
1020 	write_lock(&idev->lock);
1021 	/* Add to inet6_dev unicast addr list. */
1022 	ipv6_link_dev_addr(idev, ifa);
1023 
1024 	if (ifa->flags&IFA_F_TEMPORARY) {
1025 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
1026 		in6_ifa_hold(ifa);
1027 	}
1028 
1029 	in6_ifa_hold(ifa);
1030 	write_unlock(&idev->lock);
1031 out2:
1032 	rcu_read_unlock_bh();
1033 
1034 	if (likely(err == 0))
1035 		inet6addr_notifier_call_chain(NETDEV_UP, ifa);
1036 	else {
1037 		kfree(ifa);
1038 		ifa = ERR_PTR(err);
1039 	}
1040 
1041 	return ifa;
1042 out:
1043 	spin_unlock(&addrconf_hash_lock);
1044 	goto out2;
1045 }
1046 
1047 enum cleanup_prefix_rt_t {
1048 	CLEANUP_PREFIX_RT_NOP,    /* no cleanup action for prefix route */
1049 	CLEANUP_PREFIX_RT_DEL,    /* delete the prefix route */
1050 	CLEANUP_PREFIX_RT_EXPIRE, /* update the lifetime of the prefix route */
1051 };
1052 
1053 /*
1054  * Check, whether the prefix for ifp would still need a prefix route
1055  * after deleting ifp. The function returns one of the CLEANUP_PREFIX_RT_*
1056  * constants.
1057  *
1058  * 1) we don't purge prefix if address was not permanent.
1059  *    prefix is managed by its own lifetime.
1060  * 2) we also don't purge, if the address was IFA_F_NOPREFIXROUTE.
1061  * 3) if there are no addresses, delete prefix.
1062  * 4) if there are still other permanent address(es),
1063  *    corresponding prefix is still permanent.
1064  * 5) if there are still other addresses with IFA_F_NOPREFIXROUTE,
1065  *    don't purge the prefix, assume user space is managing it.
1066  * 6) otherwise, update prefix lifetime to the
1067  *    longest valid lifetime among the corresponding
1068  *    addresses on the device.
1069  *    Note: subsequent RA will update lifetime.
1070  **/
1071 static enum cleanup_prefix_rt_t
1072 check_cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long *expires)
1073 {
1074 	struct inet6_ifaddr *ifa;
1075 	struct inet6_dev *idev = ifp->idev;
1076 	unsigned long lifetime;
1077 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_DEL;
1078 
1079 	*expires = jiffies;
1080 
1081 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
1082 		if (ifa == ifp)
1083 			continue;
1084 		if (!ipv6_prefix_equal(&ifa->addr, &ifp->addr,
1085 				       ifp->prefix_len))
1086 			continue;
1087 		if (ifa->flags & (IFA_F_PERMANENT | IFA_F_NOPREFIXROUTE))
1088 			return CLEANUP_PREFIX_RT_NOP;
1089 
1090 		action = CLEANUP_PREFIX_RT_EXPIRE;
1091 
1092 		spin_lock(&ifa->lock);
1093 
1094 		lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
1095 		/*
1096 		 * Note: Because this address is
1097 		 * not permanent, lifetime <
1098 		 * LONG_MAX / HZ here.
1099 		 */
1100 		if (time_before(*expires, ifa->tstamp + lifetime * HZ))
1101 			*expires = ifa->tstamp + lifetime * HZ;
1102 		spin_unlock(&ifa->lock);
1103 	}
1104 
1105 	return action;
1106 }
1107 
1108 static void
1109 cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long expires, bool del_rt)
1110 {
1111 	struct rt6_info *rt;
1112 
1113 	rt = addrconf_get_prefix_route(&ifp->addr,
1114 				       ifp->prefix_len,
1115 				       ifp->idev->dev,
1116 				       0, RTF_GATEWAY | RTF_DEFAULT);
1117 	if (rt) {
1118 		if (del_rt)
1119 			ip6_del_rt(rt);
1120 		else {
1121 			if (!(rt->rt6i_flags & RTF_EXPIRES))
1122 				rt6_set_expires(rt, expires);
1123 			ip6_rt_put(rt);
1124 		}
1125 	}
1126 }
1127 
1128 
1129 /* This function wants to get referenced ifp and releases it before return */
1130 
1131 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
1132 {
1133 	int state;
1134 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_NOP;
1135 	unsigned long expires;
1136 
1137 	ASSERT_RTNL();
1138 
1139 	spin_lock_bh(&ifp->lock);
1140 	state = ifp->state;
1141 	ifp->state = INET6_IFADDR_STATE_DEAD;
1142 	spin_unlock_bh(&ifp->lock);
1143 
1144 	if (state == INET6_IFADDR_STATE_DEAD)
1145 		goto out;
1146 
1147 	spin_lock_bh(&addrconf_hash_lock);
1148 	hlist_del_init_rcu(&ifp->addr_lst);
1149 	spin_unlock_bh(&addrconf_hash_lock);
1150 
1151 	write_lock_bh(&ifp->idev->lock);
1152 
1153 	if (ifp->flags&IFA_F_TEMPORARY) {
1154 		list_del(&ifp->tmp_list);
1155 		if (ifp->ifpub) {
1156 			in6_ifa_put(ifp->ifpub);
1157 			ifp->ifpub = NULL;
1158 		}
1159 		__in6_ifa_put(ifp);
1160 	}
1161 
1162 	if (ifp->flags & IFA_F_PERMANENT && !(ifp->flags & IFA_F_NOPREFIXROUTE))
1163 		action = check_cleanup_prefix_route(ifp, &expires);
1164 
1165 	list_del_init(&ifp->if_list);
1166 	__in6_ifa_put(ifp);
1167 
1168 	write_unlock_bh(&ifp->idev->lock);
1169 
1170 	addrconf_del_dad_work(ifp);
1171 
1172 	ipv6_ifa_notify(RTM_DELADDR, ifp);
1173 
1174 	inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);
1175 
1176 	if (action != CLEANUP_PREFIX_RT_NOP) {
1177 		cleanup_prefix_route(ifp, expires,
1178 			action == CLEANUP_PREFIX_RT_DEL);
1179 	}
1180 
1181 	/* clean up prefsrc entries */
1182 	rt6_remove_prefsrc(ifp);
1183 out:
1184 	in6_ifa_put(ifp);
1185 }
1186 
1187 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp, struct inet6_ifaddr *ift)
1188 {
1189 	struct inet6_dev *idev = ifp->idev;
1190 	struct in6_addr addr, *tmpaddr;
1191 	unsigned long tmp_prefered_lft, tmp_valid_lft, tmp_tstamp, age;
1192 	unsigned long regen_advance;
1193 	int tmp_plen;
1194 	int ret = 0;
1195 	u32 addr_flags;
1196 	unsigned long now = jiffies;
1197 	long max_desync_factor;
1198 	s32 cnf_temp_preferred_lft;
1199 
1200 	write_lock_bh(&idev->lock);
1201 	if (ift) {
1202 		spin_lock_bh(&ift->lock);
1203 		memcpy(&addr.s6_addr[8], &ift->addr.s6_addr[8], 8);
1204 		spin_unlock_bh(&ift->lock);
1205 		tmpaddr = &addr;
1206 	} else {
1207 		tmpaddr = NULL;
1208 	}
1209 retry:
1210 	in6_dev_hold(idev);
1211 	if (idev->cnf.use_tempaddr <= 0) {
1212 		write_unlock_bh(&idev->lock);
1213 		pr_info("%s: use_tempaddr is disabled\n", __func__);
1214 		in6_dev_put(idev);
1215 		ret = -1;
1216 		goto out;
1217 	}
1218 	spin_lock_bh(&ifp->lock);
1219 	if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
1220 		idev->cnf.use_tempaddr = -1;	/*XXX*/
1221 		spin_unlock_bh(&ifp->lock);
1222 		write_unlock_bh(&idev->lock);
1223 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1224 			__func__);
1225 		in6_dev_put(idev);
1226 		ret = -1;
1227 		goto out;
1228 	}
1229 	in6_ifa_hold(ifp);
1230 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1231 	ipv6_try_regen_rndid(idev, tmpaddr);
1232 	memcpy(&addr.s6_addr[8], idev->rndid, 8);
1233 	age = (now - ifp->tstamp) / HZ;
1234 
1235 	regen_advance = idev->cnf.regen_max_retry *
1236 			idev->cnf.dad_transmits *
1237 			NEIGH_VAR(idev->nd_parms, RETRANS_TIME) / HZ;
1238 
1239 	/* recalculate max_desync_factor each time and update
1240 	 * idev->desync_factor if it's larger
1241 	 */
1242 	cnf_temp_preferred_lft = READ_ONCE(idev->cnf.temp_prefered_lft);
1243 	max_desync_factor = min_t(__u32,
1244 				  idev->cnf.max_desync_factor,
1245 				  cnf_temp_preferred_lft - regen_advance);
1246 
1247 	if (unlikely(idev->desync_factor > max_desync_factor)) {
1248 		if (max_desync_factor > 0) {
1249 			get_random_bytes(&idev->desync_factor,
1250 					 sizeof(idev->desync_factor));
1251 			idev->desync_factor %= max_desync_factor;
1252 		} else {
1253 			idev->desync_factor = 0;
1254 		}
1255 	}
1256 
1257 	tmp_valid_lft = min_t(__u32,
1258 			      ifp->valid_lft,
1259 			      idev->cnf.temp_valid_lft + age);
1260 	tmp_prefered_lft = cnf_temp_preferred_lft + age -
1261 			    idev->desync_factor;
1262 	tmp_prefered_lft = min_t(__u32, ifp->prefered_lft, tmp_prefered_lft);
1263 	tmp_plen = ifp->prefix_len;
1264 	tmp_tstamp = ifp->tstamp;
1265 	spin_unlock_bh(&ifp->lock);
1266 
1267 	write_unlock_bh(&idev->lock);
1268 
1269 	/* A temporary address is created only if this calculated Preferred
1270 	 * Lifetime is greater than REGEN_ADVANCE time units.  In particular,
1271 	 * an implementation must not create a temporary address with a zero
1272 	 * Preferred Lifetime.
1273 	 * Use age calculation as in addrconf_verify to avoid unnecessary
1274 	 * temporary addresses being generated.
1275 	 */
1276 	age = (now - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
1277 	if (tmp_prefered_lft <= regen_advance + age) {
1278 		in6_ifa_put(ifp);
1279 		in6_dev_put(idev);
1280 		ret = -1;
1281 		goto out;
1282 	}
1283 
1284 	addr_flags = IFA_F_TEMPORARY;
1285 	/* set in addrconf_prefix_rcv() */
1286 	if (ifp->flags & IFA_F_OPTIMISTIC)
1287 		addr_flags |= IFA_F_OPTIMISTIC;
1288 
1289 	ift = ipv6_add_addr(idev, &addr, NULL, tmp_plen,
1290 			    ipv6_addr_scope(&addr), addr_flags,
1291 			    tmp_valid_lft, tmp_prefered_lft);
1292 	if (IS_ERR(ift)) {
1293 		in6_ifa_put(ifp);
1294 		in6_dev_put(idev);
1295 		pr_info("%s: retry temporary address regeneration\n", __func__);
1296 		tmpaddr = &addr;
1297 		write_lock_bh(&idev->lock);
1298 		goto retry;
1299 	}
1300 
1301 	spin_lock_bh(&ift->lock);
1302 	ift->ifpub = ifp;
1303 	ift->cstamp = now;
1304 	ift->tstamp = tmp_tstamp;
1305 	spin_unlock_bh(&ift->lock);
1306 
1307 	addrconf_dad_start(ift);
1308 	in6_ifa_put(ift);
1309 	in6_dev_put(idev);
1310 out:
1311 	return ret;
1312 }
1313 
1314 /*
1315  *	Choose an appropriate source address (RFC3484)
1316  */
1317 enum {
1318 	IPV6_SADDR_RULE_INIT = 0,
1319 	IPV6_SADDR_RULE_LOCAL,
1320 	IPV6_SADDR_RULE_SCOPE,
1321 	IPV6_SADDR_RULE_PREFERRED,
1322 #ifdef CONFIG_IPV6_MIP6
1323 	IPV6_SADDR_RULE_HOA,
1324 #endif
1325 	IPV6_SADDR_RULE_OIF,
1326 	IPV6_SADDR_RULE_LABEL,
1327 	IPV6_SADDR_RULE_PRIVACY,
1328 	IPV6_SADDR_RULE_ORCHID,
1329 	IPV6_SADDR_RULE_PREFIX,
1330 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1331 	IPV6_SADDR_RULE_NOT_OPTIMISTIC,
1332 #endif
1333 	IPV6_SADDR_RULE_MAX
1334 };
1335 
1336 struct ipv6_saddr_score {
1337 	int			rule;
1338 	int			addr_type;
1339 	struct inet6_ifaddr	*ifa;
1340 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1341 	int			scopedist;
1342 	int			matchlen;
1343 };
1344 
1345 struct ipv6_saddr_dst {
1346 	const struct in6_addr *addr;
1347 	int ifindex;
1348 	int scope;
1349 	int label;
1350 	unsigned int prefs;
1351 };
1352 
1353 static inline int ipv6_saddr_preferred(int type)
1354 {
1355 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1356 		return 1;
1357 	return 0;
1358 }
1359 
1360 static inline bool ipv6_use_optimistic_addr(struct inet6_dev *idev)
1361 {
1362 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1363 	return idev && idev->cnf.optimistic_dad && idev->cnf.use_optimistic;
1364 #else
1365 	return false;
1366 #endif
1367 }
1368 
1369 static int ipv6_get_saddr_eval(struct net *net,
1370 			       struct ipv6_saddr_score *score,
1371 			       struct ipv6_saddr_dst *dst,
1372 			       int i)
1373 {
1374 	int ret;
1375 
1376 	if (i <= score->rule) {
1377 		switch (i) {
1378 		case IPV6_SADDR_RULE_SCOPE:
1379 			ret = score->scopedist;
1380 			break;
1381 		case IPV6_SADDR_RULE_PREFIX:
1382 			ret = score->matchlen;
1383 			break;
1384 		default:
1385 			ret = !!test_bit(i, score->scorebits);
1386 		}
1387 		goto out;
1388 	}
1389 
1390 	switch (i) {
1391 	case IPV6_SADDR_RULE_INIT:
1392 		/* Rule 0: remember if hiscore is not ready yet */
1393 		ret = !!score->ifa;
1394 		break;
1395 	case IPV6_SADDR_RULE_LOCAL:
1396 		/* Rule 1: Prefer same address */
1397 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1398 		break;
1399 	case IPV6_SADDR_RULE_SCOPE:
1400 		/* Rule 2: Prefer appropriate scope
1401 		 *
1402 		 *      ret
1403 		 *       ^
1404 		 *    -1 |  d 15
1405 		 *    ---+--+-+---> scope
1406 		 *       |
1407 		 *       |             d is scope of the destination.
1408 		 *  B-d  |  \
1409 		 *       |   \      <- smaller scope is better if
1410 		 *  B-15 |    \        if scope is enough for destination.
1411 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1412 		 * d-C-1 | /
1413 		 *       |/         <- greater is better
1414 		 *   -C  /             if scope is not enough for destination.
1415 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1416 		 *
1417 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1418 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1419 		 * Assume B = 0 and we get C > 29.
1420 		 */
1421 		ret = __ipv6_addr_src_scope(score->addr_type);
1422 		if (ret >= dst->scope)
1423 			ret = -ret;
1424 		else
1425 			ret -= 128;	/* 30 is enough */
1426 		score->scopedist = ret;
1427 		break;
1428 	case IPV6_SADDR_RULE_PREFERRED:
1429 	    {
1430 		/* Rule 3: Avoid deprecated and optimistic addresses */
1431 		u8 avoid = IFA_F_DEPRECATED;
1432 
1433 		if (!ipv6_use_optimistic_addr(score->ifa->idev))
1434 			avoid |= IFA_F_OPTIMISTIC;
1435 		ret = ipv6_saddr_preferred(score->addr_type) ||
1436 		      !(score->ifa->flags & avoid);
1437 		break;
1438 	    }
1439 #ifdef CONFIG_IPV6_MIP6
1440 	case IPV6_SADDR_RULE_HOA:
1441 	    {
1442 		/* Rule 4: Prefer home address */
1443 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1444 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1445 		break;
1446 	    }
1447 #endif
1448 	case IPV6_SADDR_RULE_OIF:
1449 		/* Rule 5: Prefer outgoing interface */
1450 		ret = (!dst->ifindex ||
1451 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1452 		break;
1453 	case IPV6_SADDR_RULE_LABEL:
1454 		/* Rule 6: Prefer matching label */
1455 		ret = ipv6_addr_label(net,
1456 				      &score->ifa->addr, score->addr_type,
1457 				      score->ifa->idev->dev->ifindex) == dst->label;
1458 		break;
1459 	case IPV6_SADDR_RULE_PRIVACY:
1460 	    {
1461 		/* Rule 7: Prefer public address
1462 		 * Note: prefer temporary address if use_tempaddr >= 2
1463 		 */
1464 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1465 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1466 				score->ifa->idev->cnf.use_tempaddr >= 2;
1467 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1468 		break;
1469 	    }
1470 	case IPV6_SADDR_RULE_ORCHID:
1471 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1472 		 *	    non-ORCHID vs non-ORCHID
1473 		 */
1474 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1475 			ipv6_addr_orchid(dst->addr));
1476 		break;
1477 	case IPV6_SADDR_RULE_PREFIX:
1478 		/* Rule 8: Use longest matching prefix */
1479 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1480 		if (ret > score->ifa->prefix_len)
1481 			ret = score->ifa->prefix_len;
1482 		score->matchlen = ret;
1483 		break;
1484 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1485 	case IPV6_SADDR_RULE_NOT_OPTIMISTIC:
1486 		/* Optimistic addresses still have lower precedence than other
1487 		 * preferred addresses.
1488 		 */
1489 		ret = !(score->ifa->flags & IFA_F_OPTIMISTIC);
1490 		break;
1491 #endif
1492 	default:
1493 		ret = 0;
1494 	}
1495 
1496 	if (ret)
1497 		__set_bit(i, score->scorebits);
1498 	score->rule = i;
1499 out:
1500 	return ret;
1501 }
1502 
1503 static int __ipv6_dev_get_saddr(struct net *net,
1504 				struct ipv6_saddr_dst *dst,
1505 				struct inet6_dev *idev,
1506 				struct ipv6_saddr_score *scores,
1507 				int hiscore_idx)
1508 {
1509 	struct ipv6_saddr_score *score = &scores[1 - hiscore_idx], *hiscore = &scores[hiscore_idx];
1510 
1511 	read_lock_bh(&idev->lock);
1512 	list_for_each_entry(score->ifa, &idev->addr_list, if_list) {
1513 		int i;
1514 
1515 		/*
1516 		 * - Tentative Address (RFC2462 section 5.4)
1517 		 *  - A tentative address is not considered
1518 		 *    "assigned to an interface" in the traditional
1519 		 *    sense, unless it is also flagged as optimistic.
1520 		 * - Candidate Source Address (section 4)
1521 		 *  - In any case, anycast addresses, multicast
1522 		 *    addresses, and the unspecified address MUST
1523 		 *    NOT be included in a candidate set.
1524 		 */
1525 		if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1526 		    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1527 			continue;
1528 
1529 		score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1530 
1531 		if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1532 			     score->addr_type & IPV6_ADDR_MULTICAST)) {
1533 			net_dbg_ratelimited("ADDRCONF: unspecified / multicast address assigned as unicast address on %s",
1534 					    idev->dev->name);
1535 			continue;
1536 		}
1537 
1538 		score->rule = -1;
1539 		bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1540 
1541 		for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1542 			int minihiscore, miniscore;
1543 
1544 			minihiscore = ipv6_get_saddr_eval(net, hiscore, dst, i);
1545 			miniscore = ipv6_get_saddr_eval(net, score, dst, i);
1546 
1547 			if (minihiscore > miniscore) {
1548 				if (i == IPV6_SADDR_RULE_SCOPE &&
1549 				    score->scopedist > 0) {
1550 					/*
1551 					 * special case:
1552 					 * each remaining entry
1553 					 * has too small (not enough)
1554 					 * scope, because ifa entries
1555 					 * are sorted by their scope
1556 					 * values.
1557 					 */
1558 					goto out;
1559 				}
1560 				break;
1561 			} else if (minihiscore < miniscore) {
1562 				if (hiscore->ifa)
1563 					in6_ifa_put(hiscore->ifa);
1564 
1565 				in6_ifa_hold(score->ifa);
1566 
1567 				swap(hiscore, score);
1568 				hiscore_idx = 1 - hiscore_idx;
1569 
1570 				/* restore our iterator */
1571 				score->ifa = hiscore->ifa;
1572 
1573 				break;
1574 			}
1575 		}
1576 	}
1577 out:
1578 	read_unlock_bh(&idev->lock);
1579 	return hiscore_idx;
1580 }
1581 
1582 static int ipv6_get_saddr_master(struct net *net,
1583 				 const struct net_device *dst_dev,
1584 				 const struct net_device *master,
1585 				 struct ipv6_saddr_dst *dst,
1586 				 struct ipv6_saddr_score *scores,
1587 				 int hiscore_idx)
1588 {
1589 	struct inet6_dev *idev;
1590 
1591 	idev = __in6_dev_get(dst_dev);
1592 	if (idev)
1593 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1594 						   scores, hiscore_idx);
1595 
1596 	idev = __in6_dev_get(master);
1597 	if (idev)
1598 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1599 						   scores, hiscore_idx);
1600 
1601 	return hiscore_idx;
1602 }
1603 
1604 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1605 		       const struct in6_addr *daddr, unsigned int prefs,
1606 		       struct in6_addr *saddr)
1607 {
1608 	struct ipv6_saddr_score scores[2], *hiscore;
1609 	struct ipv6_saddr_dst dst;
1610 	struct inet6_dev *idev;
1611 	struct net_device *dev;
1612 	int dst_type;
1613 	bool use_oif_addr = false;
1614 	int hiscore_idx = 0;
1615 
1616 	dst_type = __ipv6_addr_type(daddr);
1617 	dst.addr = daddr;
1618 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1619 	dst.scope = __ipv6_addr_src_scope(dst_type);
1620 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1621 	dst.prefs = prefs;
1622 
1623 	scores[hiscore_idx].rule = -1;
1624 	scores[hiscore_idx].ifa = NULL;
1625 
1626 	rcu_read_lock();
1627 
1628 	/* Candidate Source Address (section 4)
1629 	 *  - multicast and link-local destination address,
1630 	 *    the set of candidate source address MUST only
1631 	 *    include addresses assigned to interfaces
1632 	 *    belonging to the same link as the outgoing
1633 	 *    interface.
1634 	 * (- For site-local destination addresses, the
1635 	 *    set of candidate source addresses MUST only
1636 	 *    include addresses assigned to interfaces
1637 	 *    belonging to the same site as the outgoing
1638 	 *    interface.)
1639 	 *  - "It is RECOMMENDED that the candidate source addresses
1640 	 *    be the set of unicast addresses assigned to the
1641 	 *    interface that will be used to send to the destination
1642 	 *    (the 'outgoing' interface)." (RFC 6724)
1643 	 */
1644 	if (dst_dev) {
1645 		idev = __in6_dev_get(dst_dev);
1646 		if ((dst_type & IPV6_ADDR_MULTICAST) ||
1647 		    dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL ||
1648 		    (idev && idev->cnf.use_oif_addrs_only)) {
1649 			use_oif_addr = true;
1650 		}
1651 	}
1652 
1653 	if (use_oif_addr) {
1654 		if (idev)
1655 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1656 	} else {
1657 		const struct net_device *master;
1658 		int master_idx = 0;
1659 
1660 		/* if dst_dev exists and is enslaved to an L3 device, then
1661 		 * prefer addresses from dst_dev and then the master over
1662 		 * any other enslaved devices in the L3 domain.
1663 		 */
1664 		master = l3mdev_master_dev_rcu(dst_dev);
1665 		if (master) {
1666 			master_idx = master->ifindex;
1667 
1668 			hiscore_idx = ipv6_get_saddr_master(net, dst_dev,
1669 							    master, &dst,
1670 							    scores, hiscore_idx);
1671 
1672 			if (scores[hiscore_idx].ifa)
1673 				goto out;
1674 		}
1675 
1676 		for_each_netdev_rcu(net, dev) {
1677 			/* only consider addresses on devices in the
1678 			 * same L3 domain
1679 			 */
1680 			if (l3mdev_master_ifindex_rcu(dev) != master_idx)
1681 				continue;
1682 			idev = __in6_dev_get(dev);
1683 			if (!idev)
1684 				continue;
1685 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1686 		}
1687 	}
1688 
1689 out:
1690 	rcu_read_unlock();
1691 
1692 	hiscore = &scores[hiscore_idx];
1693 	if (!hiscore->ifa)
1694 		return -EADDRNOTAVAIL;
1695 
1696 	*saddr = hiscore->ifa->addr;
1697 	in6_ifa_put(hiscore->ifa);
1698 	return 0;
1699 }
1700 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1701 
1702 int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr,
1703 		      u32 banned_flags)
1704 {
1705 	struct inet6_ifaddr *ifp;
1706 	int err = -EADDRNOTAVAIL;
1707 
1708 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1709 		if (ifp->scope > IFA_LINK)
1710 			break;
1711 		if (ifp->scope == IFA_LINK &&
1712 		    !(ifp->flags & banned_flags)) {
1713 			*addr = ifp->addr;
1714 			err = 0;
1715 			break;
1716 		}
1717 	}
1718 	return err;
1719 }
1720 
1721 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1722 		    u32 banned_flags)
1723 {
1724 	struct inet6_dev *idev;
1725 	int err = -EADDRNOTAVAIL;
1726 
1727 	rcu_read_lock();
1728 	idev = __in6_dev_get(dev);
1729 	if (idev) {
1730 		read_lock_bh(&idev->lock);
1731 		err = __ipv6_get_lladdr(idev, addr, banned_flags);
1732 		read_unlock_bh(&idev->lock);
1733 	}
1734 	rcu_read_unlock();
1735 	return err;
1736 }
1737 
1738 static int ipv6_count_addresses(struct inet6_dev *idev)
1739 {
1740 	int cnt = 0;
1741 	struct inet6_ifaddr *ifp;
1742 
1743 	read_lock_bh(&idev->lock);
1744 	list_for_each_entry(ifp, &idev->addr_list, if_list)
1745 		cnt++;
1746 	read_unlock_bh(&idev->lock);
1747 	return cnt;
1748 }
1749 
1750 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1751 		  const struct net_device *dev, int strict)
1752 {
1753 	return ipv6_chk_addr_and_flags(net, addr, dev, strict, IFA_F_TENTATIVE);
1754 }
1755 EXPORT_SYMBOL(ipv6_chk_addr);
1756 
1757 int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
1758 			    const struct net_device *dev, int strict,
1759 			    u32 banned_flags)
1760 {
1761 	struct inet6_ifaddr *ifp;
1762 	unsigned int hash = inet6_addr_hash(addr);
1763 	u32 ifp_flags;
1764 
1765 	rcu_read_lock_bh();
1766 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
1767 		if (!net_eq(dev_net(ifp->idev->dev), net))
1768 			continue;
1769 		/* Decouple optimistic from tentative for evaluation here.
1770 		 * Ban optimistic addresses explicitly, when required.
1771 		 */
1772 		ifp_flags = (ifp->flags&IFA_F_OPTIMISTIC)
1773 			    ? (ifp->flags&~IFA_F_TENTATIVE)
1774 			    : ifp->flags;
1775 		if (ipv6_addr_equal(&ifp->addr, addr) &&
1776 		    !(ifp_flags&banned_flags) &&
1777 		    (!dev || ifp->idev->dev == dev ||
1778 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1779 			rcu_read_unlock_bh();
1780 			return 1;
1781 		}
1782 	}
1783 
1784 	rcu_read_unlock_bh();
1785 	return 0;
1786 }
1787 EXPORT_SYMBOL(ipv6_chk_addr_and_flags);
1788 
1789 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
1790 			       struct net_device *dev)
1791 {
1792 	unsigned int hash = inet6_addr_hash(addr);
1793 	struct inet6_ifaddr *ifp;
1794 
1795 	hlist_for_each_entry(ifp, &inet6_addr_lst[hash], addr_lst) {
1796 		if (!net_eq(dev_net(ifp->idev->dev), net))
1797 			continue;
1798 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1799 			if (!dev || ifp->idev->dev == dev)
1800 				return true;
1801 		}
1802 	}
1803 	return false;
1804 }
1805 
1806 /* Compares an address/prefix_len with addresses on device @dev.
1807  * If one is found it returns true.
1808  */
1809 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
1810 	const unsigned int prefix_len, struct net_device *dev)
1811 {
1812 	struct inet6_dev *idev;
1813 	struct inet6_ifaddr *ifa;
1814 	bool ret = false;
1815 
1816 	rcu_read_lock();
1817 	idev = __in6_dev_get(dev);
1818 	if (idev) {
1819 		read_lock_bh(&idev->lock);
1820 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
1821 			ret = ipv6_prefix_equal(addr, &ifa->addr, prefix_len);
1822 			if (ret)
1823 				break;
1824 		}
1825 		read_unlock_bh(&idev->lock);
1826 	}
1827 	rcu_read_unlock();
1828 
1829 	return ret;
1830 }
1831 EXPORT_SYMBOL(ipv6_chk_custom_prefix);
1832 
1833 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
1834 {
1835 	struct inet6_dev *idev;
1836 	struct inet6_ifaddr *ifa;
1837 	int	onlink;
1838 
1839 	onlink = 0;
1840 	rcu_read_lock();
1841 	idev = __in6_dev_get(dev);
1842 	if (idev) {
1843 		read_lock_bh(&idev->lock);
1844 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
1845 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
1846 						   ifa->prefix_len);
1847 			if (onlink)
1848 				break;
1849 		}
1850 		read_unlock_bh(&idev->lock);
1851 	}
1852 	rcu_read_unlock();
1853 	return onlink;
1854 }
1855 EXPORT_SYMBOL(ipv6_chk_prefix);
1856 
1857 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
1858 				     struct net_device *dev, int strict)
1859 {
1860 	struct inet6_ifaddr *ifp, *result = NULL;
1861 	unsigned int hash = inet6_addr_hash(addr);
1862 
1863 	rcu_read_lock_bh();
1864 	hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[hash], addr_lst) {
1865 		if (!net_eq(dev_net(ifp->idev->dev), net))
1866 			continue;
1867 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1868 			if (!dev || ifp->idev->dev == dev ||
1869 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
1870 				result = ifp;
1871 				in6_ifa_hold(ifp);
1872 				break;
1873 			}
1874 		}
1875 	}
1876 	rcu_read_unlock_bh();
1877 
1878 	return result;
1879 }
1880 
1881 /* Gets referenced address, destroys ifaddr */
1882 
1883 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
1884 {
1885 	if (dad_failed)
1886 		ifp->flags |= IFA_F_DADFAILED;
1887 
1888 	if (ifp->flags&IFA_F_PERMANENT) {
1889 		spin_lock_bh(&ifp->lock);
1890 		addrconf_del_dad_work(ifp);
1891 		ifp->flags |= IFA_F_TENTATIVE;
1892 		spin_unlock_bh(&ifp->lock);
1893 		if (dad_failed)
1894 			ipv6_ifa_notify(0, ifp);
1895 		in6_ifa_put(ifp);
1896 	} else if (ifp->flags&IFA_F_TEMPORARY) {
1897 		struct inet6_ifaddr *ifpub;
1898 		spin_lock_bh(&ifp->lock);
1899 		ifpub = ifp->ifpub;
1900 		if (ifpub) {
1901 			in6_ifa_hold(ifpub);
1902 			spin_unlock_bh(&ifp->lock);
1903 			ipv6_create_tempaddr(ifpub, ifp);
1904 			in6_ifa_put(ifpub);
1905 		} else {
1906 			spin_unlock_bh(&ifp->lock);
1907 		}
1908 		ipv6_del_addr(ifp);
1909 	} else {
1910 		ipv6_del_addr(ifp);
1911 	}
1912 }
1913 
1914 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
1915 {
1916 	int err = -ENOENT;
1917 
1918 	spin_lock_bh(&ifp->lock);
1919 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
1920 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
1921 		err = 0;
1922 	}
1923 	spin_unlock_bh(&ifp->lock);
1924 
1925 	return err;
1926 }
1927 
1928 void addrconf_dad_failure(struct inet6_ifaddr *ifp)
1929 {
1930 	struct inet6_dev *idev = ifp->idev;
1931 	struct net *net = dev_net(ifp->idev->dev);
1932 
1933 	if (addrconf_dad_end(ifp)) {
1934 		in6_ifa_put(ifp);
1935 		return;
1936 	}
1937 
1938 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c detected!\n",
1939 			     ifp->idev->dev->name, &ifp->addr);
1940 
1941 	spin_lock_bh(&ifp->lock);
1942 
1943 	if (ifp->flags & IFA_F_STABLE_PRIVACY) {
1944 		int scope = ifp->scope;
1945 		u32 flags = ifp->flags;
1946 		struct in6_addr new_addr;
1947 		struct inet6_ifaddr *ifp2;
1948 		u32 valid_lft, preferred_lft;
1949 		int pfxlen = ifp->prefix_len;
1950 		int retries = ifp->stable_privacy_retry + 1;
1951 
1952 		if (retries > net->ipv6.sysctl.idgen_retries) {
1953 			net_info_ratelimited("%s: privacy stable address generation failed because of DAD conflicts!\n",
1954 					     ifp->idev->dev->name);
1955 			goto errdad;
1956 		}
1957 
1958 		new_addr = ifp->addr;
1959 		if (ipv6_generate_stable_address(&new_addr, retries,
1960 						 idev))
1961 			goto errdad;
1962 
1963 		valid_lft = ifp->valid_lft;
1964 		preferred_lft = ifp->prefered_lft;
1965 
1966 		spin_unlock_bh(&ifp->lock);
1967 
1968 		if (idev->cnf.max_addresses &&
1969 		    ipv6_count_addresses(idev) >=
1970 		    idev->cnf.max_addresses)
1971 			goto lock_errdad;
1972 
1973 		net_info_ratelimited("%s: generating new stable privacy address because of DAD conflict\n",
1974 				     ifp->idev->dev->name);
1975 
1976 		ifp2 = ipv6_add_addr(idev, &new_addr, NULL, pfxlen,
1977 				     scope, flags, valid_lft,
1978 				     preferred_lft);
1979 		if (IS_ERR(ifp2))
1980 			goto lock_errdad;
1981 
1982 		spin_lock_bh(&ifp2->lock);
1983 		ifp2->stable_privacy_retry = retries;
1984 		ifp2->state = INET6_IFADDR_STATE_PREDAD;
1985 		spin_unlock_bh(&ifp2->lock);
1986 
1987 		addrconf_mod_dad_work(ifp2, net->ipv6.sysctl.idgen_delay);
1988 		in6_ifa_put(ifp2);
1989 lock_errdad:
1990 		spin_lock_bh(&ifp->lock);
1991 	}
1992 
1993 errdad:
1994 	/* transition from _POSTDAD to _ERRDAD */
1995 	ifp->state = INET6_IFADDR_STATE_ERRDAD;
1996 	spin_unlock_bh(&ifp->lock);
1997 
1998 	addrconf_mod_dad_work(ifp, 0);
1999 	in6_ifa_put(ifp);
2000 }
2001 
2002 /* Join to solicited addr multicast group.
2003  * caller must hold RTNL */
2004 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
2005 {
2006 	struct in6_addr maddr;
2007 
2008 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2009 		return;
2010 
2011 	addrconf_addr_solict_mult(addr, &maddr);
2012 	ipv6_dev_mc_inc(dev, &maddr);
2013 }
2014 
2015 /* caller must hold RTNL */
2016 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
2017 {
2018 	struct in6_addr maddr;
2019 
2020 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2021 		return;
2022 
2023 	addrconf_addr_solict_mult(addr, &maddr);
2024 	__ipv6_dev_mc_dec(idev, &maddr);
2025 }
2026 
2027 /* caller must hold RTNL */
2028 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
2029 {
2030 	struct in6_addr addr;
2031 
2032 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2033 		return;
2034 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2035 	if (ipv6_addr_any(&addr))
2036 		return;
2037 	__ipv6_dev_ac_inc(ifp->idev, &addr);
2038 }
2039 
2040 /* caller must hold RTNL */
2041 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
2042 {
2043 	struct in6_addr addr;
2044 
2045 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2046 		return;
2047 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2048 	if (ipv6_addr_any(&addr))
2049 		return;
2050 	__ipv6_dev_ac_dec(ifp->idev, &addr);
2051 }
2052 
2053 static int addrconf_ifid_eui64(u8 *eui, struct net_device *dev)
2054 {
2055 	if (dev->addr_len != EUI64_ADDR_LEN)
2056 		return -1;
2057 	memcpy(eui, dev->dev_addr, EUI64_ADDR_LEN);
2058 	eui[0] ^= 2;
2059 	return 0;
2060 }
2061 
2062 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
2063 {
2064 	union fwnet_hwaddr *ha;
2065 
2066 	if (dev->addr_len != FWNET_ALEN)
2067 		return -1;
2068 
2069 	ha = (union fwnet_hwaddr *)dev->dev_addr;
2070 
2071 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
2072 	eui[0] ^= 2;
2073 	return 0;
2074 }
2075 
2076 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
2077 {
2078 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
2079 	if (dev->addr_len != ARCNET_ALEN)
2080 		return -1;
2081 	memset(eui, 0, 7);
2082 	eui[7] = *(u8 *)dev->dev_addr;
2083 	return 0;
2084 }
2085 
2086 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
2087 {
2088 	if (dev->addr_len != INFINIBAND_ALEN)
2089 		return -1;
2090 	memcpy(eui, dev->dev_addr + 12, 8);
2091 	eui[0] |= 2;
2092 	return 0;
2093 }
2094 
2095 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
2096 {
2097 	if (addr == 0)
2098 		return -1;
2099 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
2100 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
2101 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
2102 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
2103 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
2104 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
2105 	eui[1] = 0;
2106 	eui[2] = 0x5E;
2107 	eui[3] = 0xFE;
2108 	memcpy(eui + 4, &addr, 4);
2109 	return 0;
2110 }
2111 
2112 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
2113 {
2114 	if (dev->priv_flags & IFF_ISATAP)
2115 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2116 	return -1;
2117 }
2118 
2119 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
2120 {
2121 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2122 }
2123 
2124 static int addrconf_ifid_ip6tnl(u8 *eui, struct net_device *dev)
2125 {
2126 	memcpy(eui, dev->perm_addr, 3);
2127 	memcpy(eui + 5, dev->perm_addr + 3, 3);
2128 	eui[3] = 0xFF;
2129 	eui[4] = 0xFE;
2130 	eui[0] ^= 2;
2131 	return 0;
2132 }
2133 
2134 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
2135 {
2136 	switch (dev->type) {
2137 	case ARPHRD_ETHER:
2138 	case ARPHRD_FDDI:
2139 		return addrconf_ifid_eui48(eui, dev);
2140 	case ARPHRD_ARCNET:
2141 		return addrconf_ifid_arcnet(eui, dev);
2142 	case ARPHRD_INFINIBAND:
2143 		return addrconf_ifid_infiniband(eui, dev);
2144 	case ARPHRD_SIT:
2145 		return addrconf_ifid_sit(eui, dev);
2146 	case ARPHRD_IPGRE:
2147 		return addrconf_ifid_gre(eui, dev);
2148 	case ARPHRD_6LOWPAN:
2149 		return addrconf_ifid_eui64(eui, dev);
2150 	case ARPHRD_IEEE1394:
2151 		return addrconf_ifid_ieee1394(eui, dev);
2152 	case ARPHRD_TUNNEL6:
2153 		return addrconf_ifid_ip6tnl(eui, dev);
2154 	}
2155 	return -1;
2156 }
2157 
2158 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
2159 {
2160 	int err = -1;
2161 	struct inet6_ifaddr *ifp;
2162 
2163 	read_lock_bh(&idev->lock);
2164 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
2165 		if (ifp->scope > IFA_LINK)
2166 			break;
2167 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
2168 			memcpy(eui, ifp->addr.s6_addr+8, 8);
2169 			err = 0;
2170 			break;
2171 		}
2172 	}
2173 	read_unlock_bh(&idev->lock);
2174 	return err;
2175 }
2176 
2177 /* (re)generation of randomized interface identifier (RFC 3041 3.2, 3.5) */
2178 static void ipv6_regen_rndid(struct inet6_dev *idev)
2179 {
2180 regen:
2181 	get_random_bytes(idev->rndid, sizeof(idev->rndid));
2182 	idev->rndid[0] &= ~0x02;
2183 
2184 	/*
2185 	 * <draft-ietf-ipngwg-temp-addresses-v2-00.txt>:
2186 	 * check if generated address is not inappropriate
2187 	 *
2188 	 *  - Reserved subnet anycast (RFC 2526)
2189 	 *	11111101 11....11 1xxxxxxx
2190 	 *  - ISATAP (RFC4214) 6.1
2191 	 *	00-00-5E-FE-xx-xx-xx-xx
2192 	 *  - value 0
2193 	 *  - XXX: already assigned to an address on the device
2194 	 */
2195 	if (idev->rndid[0] == 0xfd &&
2196 	    (idev->rndid[1]&idev->rndid[2]&idev->rndid[3]&idev->rndid[4]&idev->rndid[5]&idev->rndid[6]) == 0xff &&
2197 	    (idev->rndid[7]&0x80))
2198 		goto regen;
2199 	if ((idev->rndid[0]|idev->rndid[1]) == 0) {
2200 		if (idev->rndid[2] == 0x5e && idev->rndid[3] == 0xfe)
2201 			goto regen;
2202 		if ((idev->rndid[2]|idev->rndid[3]|idev->rndid[4]|idev->rndid[5]|idev->rndid[6]|idev->rndid[7]) == 0x00)
2203 			goto regen;
2204 	}
2205 }
2206 
2207 static void  ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr)
2208 {
2209 	if (tmpaddr && memcmp(idev->rndid, &tmpaddr->s6_addr[8], 8) == 0)
2210 		ipv6_regen_rndid(idev);
2211 }
2212 
2213 /*
2214  *	Add prefix route.
2215  */
2216 
2217 static void
2218 addrconf_prefix_route(struct in6_addr *pfx, int plen, struct net_device *dev,
2219 		      unsigned long expires, u32 flags)
2220 {
2221 	struct fib6_config cfg = {
2222 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX,
2223 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2224 		.fc_ifindex = dev->ifindex,
2225 		.fc_expires = expires,
2226 		.fc_dst_len = plen,
2227 		.fc_flags = RTF_UP | flags,
2228 		.fc_nlinfo.nl_net = dev_net(dev),
2229 		.fc_protocol = RTPROT_KERNEL,
2230 	};
2231 
2232 	cfg.fc_dst = *pfx;
2233 
2234 	/* Prevent useless cloning on PtP SIT.
2235 	   This thing is done here expecting that the whole
2236 	   class of non-broadcast devices need not cloning.
2237 	 */
2238 #if IS_ENABLED(CONFIG_IPV6_SIT)
2239 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
2240 		cfg.fc_flags |= RTF_NONEXTHOP;
2241 #endif
2242 
2243 	ip6_route_add(&cfg);
2244 }
2245 
2246 
2247 static struct rt6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
2248 						  int plen,
2249 						  const struct net_device *dev,
2250 						  u32 flags, u32 noflags)
2251 {
2252 	struct fib6_node *fn;
2253 	struct rt6_info *rt = NULL;
2254 	struct fib6_table *table;
2255 	u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX;
2256 
2257 	table = fib6_get_table(dev_net(dev), tb_id);
2258 	if (!table)
2259 		return NULL;
2260 
2261 	read_lock_bh(&table->tb6_lock);
2262 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0);
2263 	if (!fn)
2264 		goto out;
2265 
2266 	noflags |= RTF_CACHE;
2267 	for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
2268 		if (rt->dst.dev->ifindex != dev->ifindex)
2269 			continue;
2270 		if ((rt->rt6i_flags & flags) != flags)
2271 			continue;
2272 		if ((rt->rt6i_flags & noflags) != 0)
2273 			continue;
2274 		dst_hold(&rt->dst);
2275 		break;
2276 	}
2277 out:
2278 	read_unlock_bh(&table->tb6_lock);
2279 	return rt;
2280 }
2281 
2282 
2283 /* Create "default" multicast route to the interface */
2284 
2285 static void addrconf_add_mroute(struct net_device *dev)
2286 {
2287 	struct fib6_config cfg = {
2288 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_LOCAL,
2289 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2290 		.fc_ifindex = dev->ifindex,
2291 		.fc_dst_len = 8,
2292 		.fc_flags = RTF_UP,
2293 		.fc_nlinfo.nl_net = dev_net(dev),
2294 	};
2295 
2296 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
2297 
2298 	ip6_route_add(&cfg);
2299 }
2300 
2301 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2302 {
2303 	struct inet6_dev *idev;
2304 
2305 	ASSERT_RTNL();
2306 
2307 	idev = ipv6_find_idev(dev);
2308 	if (!idev)
2309 		return ERR_PTR(-ENOBUFS);
2310 
2311 	if (idev->cnf.disable_ipv6)
2312 		return ERR_PTR(-EACCES);
2313 
2314 	/* Add default multicast route */
2315 	if (!(dev->flags & IFF_LOOPBACK) && !netif_is_l3_master(dev))
2316 		addrconf_add_mroute(dev);
2317 
2318 	return idev;
2319 }
2320 
2321 static void manage_tempaddrs(struct inet6_dev *idev,
2322 			     struct inet6_ifaddr *ifp,
2323 			     __u32 valid_lft, __u32 prefered_lft,
2324 			     bool create, unsigned long now)
2325 {
2326 	u32 flags;
2327 	struct inet6_ifaddr *ift;
2328 
2329 	read_lock_bh(&idev->lock);
2330 	/* update all temporary addresses in the list */
2331 	list_for_each_entry(ift, &idev->tempaddr_list, tmp_list) {
2332 		int age, max_valid, max_prefered;
2333 
2334 		if (ifp != ift->ifpub)
2335 			continue;
2336 
2337 		/* RFC 4941 section 3.3:
2338 		 * If a received option will extend the lifetime of a public
2339 		 * address, the lifetimes of temporary addresses should
2340 		 * be extended, subject to the overall constraint that no
2341 		 * temporary addresses should ever remain "valid" or "preferred"
2342 		 * for a time longer than (TEMP_VALID_LIFETIME) or
2343 		 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR), respectively.
2344 		 */
2345 		age = (now - ift->cstamp) / HZ;
2346 		max_valid = idev->cnf.temp_valid_lft - age;
2347 		if (max_valid < 0)
2348 			max_valid = 0;
2349 
2350 		max_prefered = idev->cnf.temp_prefered_lft -
2351 			       idev->desync_factor - age;
2352 		if (max_prefered < 0)
2353 			max_prefered = 0;
2354 
2355 		if (valid_lft > max_valid)
2356 			valid_lft = max_valid;
2357 
2358 		if (prefered_lft > max_prefered)
2359 			prefered_lft = max_prefered;
2360 
2361 		spin_lock(&ift->lock);
2362 		flags = ift->flags;
2363 		ift->valid_lft = valid_lft;
2364 		ift->prefered_lft = prefered_lft;
2365 		ift->tstamp = now;
2366 		if (prefered_lft > 0)
2367 			ift->flags &= ~IFA_F_DEPRECATED;
2368 
2369 		spin_unlock(&ift->lock);
2370 		if (!(flags&IFA_F_TENTATIVE))
2371 			ipv6_ifa_notify(0, ift);
2372 	}
2373 
2374 	if ((create || list_empty(&idev->tempaddr_list)) &&
2375 	    idev->cnf.use_tempaddr > 0) {
2376 		/* When a new public address is created as described
2377 		 * in [ADDRCONF], also create a new temporary address.
2378 		 * Also create a temporary address if it's enabled but
2379 		 * no temporary address currently exists.
2380 		 */
2381 		read_unlock_bh(&idev->lock);
2382 		ipv6_create_tempaddr(ifp, NULL);
2383 	} else {
2384 		read_unlock_bh(&idev->lock);
2385 	}
2386 }
2387 
2388 static bool is_addr_mode_generate_stable(struct inet6_dev *idev)
2389 {
2390 	return idev->addr_gen_mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY ||
2391 	       idev->addr_gen_mode == IN6_ADDR_GEN_MODE_RANDOM;
2392 }
2393 
2394 int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
2395 				 const struct prefix_info *pinfo,
2396 				 struct inet6_dev *in6_dev,
2397 				 const struct in6_addr *addr, int addr_type,
2398 				 u32 addr_flags, bool sllao, bool tokenized,
2399 				 __u32 valid_lft, u32 prefered_lft)
2400 {
2401 	struct inet6_ifaddr *ifp = ipv6_get_ifaddr(net, addr, dev, 1);
2402 	int create = 0, update_lft = 0;
2403 
2404 	if (!ifp && valid_lft) {
2405 		int max_addresses = in6_dev->cnf.max_addresses;
2406 
2407 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2408 		if (in6_dev->cnf.optimistic_dad &&
2409 		    !net->ipv6.devconf_all->forwarding && sllao)
2410 			addr_flags |= IFA_F_OPTIMISTIC;
2411 #endif
2412 
2413 		/* Do not allow to create too much of autoconfigured
2414 		 * addresses; this would be too easy way to crash kernel.
2415 		 */
2416 		if (!max_addresses ||
2417 		    ipv6_count_addresses(in6_dev) < max_addresses)
2418 			ifp = ipv6_add_addr(in6_dev, addr, NULL,
2419 					    pinfo->prefix_len,
2420 					    addr_type&IPV6_ADDR_SCOPE_MASK,
2421 					    addr_flags, valid_lft,
2422 					    prefered_lft);
2423 
2424 		if (IS_ERR_OR_NULL(ifp))
2425 			return -1;
2426 
2427 		update_lft = 0;
2428 		create = 1;
2429 		spin_lock_bh(&ifp->lock);
2430 		ifp->flags |= IFA_F_MANAGETEMPADDR;
2431 		ifp->cstamp = jiffies;
2432 		ifp->tokenized = tokenized;
2433 		spin_unlock_bh(&ifp->lock);
2434 		addrconf_dad_start(ifp);
2435 	}
2436 
2437 	if (ifp) {
2438 		u32 flags;
2439 		unsigned long now;
2440 		u32 stored_lft;
2441 
2442 		/* update lifetime (RFC2462 5.5.3 e) */
2443 		spin_lock_bh(&ifp->lock);
2444 		now = jiffies;
2445 		if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2446 			stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2447 		else
2448 			stored_lft = 0;
2449 		if (!update_lft && !create && stored_lft) {
2450 			const u32 minimum_lft = min_t(u32,
2451 				stored_lft, MIN_VALID_LIFETIME);
2452 			valid_lft = max(valid_lft, minimum_lft);
2453 
2454 			/* RFC4862 Section 5.5.3e:
2455 			 * "Note that the preferred lifetime of the
2456 			 *  corresponding address is always reset to
2457 			 *  the Preferred Lifetime in the received
2458 			 *  Prefix Information option, regardless of
2459 			 *  whether the valid lifetime is also reset or
2460 			 *  ignored."
2461 			 *
2462 			 * So we should always update prefered_lft here.
2463 			 */
2464 			update_lft = 1;
2465 		}
2466 
2467 		if (update_lft) {
2468 			ifp->valid_lft = valid_lft;
2469 			ifp->prefered_lft = prefered_lft;
2470 			ifp->tstamp = now;
2471 			flags = ifp->flags;
2472 			ifp->flags &= ~IFA_F_DEPRECATED;
2473 			spin_unlock_bh(&ifp->lock);
2474 
2475 			if (!(flags&IFA_F_TENTATIVE))
2476 				ipv6_ifa_notify(0, ifp);
2477 		} else
2478 			spin_unlock_bh(&ifp->lock);
2479 
2480 		manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
2481 				 create, now);
2482 
2483 		in6_ifa_put(ifp);
2484 		addrconf_verify();
2485 	}
2486 
2487 	return 0;
2488 }
2489 EXPORT_SYMBOL_GPL(addrconf_prefix_rcv_add_addr);
2490 
2491 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2492 {
2493 	struct prefix_info *pinfo;
2494 	__u32 valid_lft;
2495 	__u32 prefered_lft;
2496 	int addr_type, err;
2497 	u32 addr_flags = 0;
2498 	struct inet6_dev *in6_dev;
2499 	struct net *net = dev_net(dev);
2500 
2501 	pinfo = (struct prefix_info *) opt;
2502 
2503 	if (len < sizeof(struct prefix_info)) {
2504 		ADBG("addrconf: prefix option too short\n");
2505 		return;
2506 	}
2507 
2508 	/*
2509 	 *	Validation checks ([ADDRCONF], page 19)
2510 	 */
2511 
2512 	addr_type = ipv6_addr_type(&pinfo->prefix);
2513 
2514 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2515 		return;
2516 
2517 	valid_lft = ntohl(pinfo->valid);
2518 	prefered_lft = ntohl(pinfo->prefered);
2519 
2520 	if (prefered_lft > valid_lft) {
2521 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2522 		return;
2523 	}
2524 
2525 	in6_dev = in6_dev_get(dev);
2526 
2527 	if (!in6_dev) {
2528 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2529 				    dev->name);
2530 		return;
2531 	}
2532 
2533 	/*
2534 	 *	Two things going on here:
2535 	 *	1) Add routes for on-link prefixes
2536 	 *	2) Configure prefixes with the auto flag set
2537 	 */
2538 
2539 	if (pinfo->onlink) {
2540 		struct rt6_info *rt;
2541 		unsigned long rt_expires;
2542 
2543 		/* Avoid arithmetic overflow. Really, we could
2544 		 * save rt_expires in seconds, likely valid_lft,
2545 		 * but it would require division in fib gc, that it
2546 		 * not good.
2547 		 */
2548 		if (HZ > USER_HZ)
2549 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2550 		else
2551 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2552 
2553 		if (addrconf_finite_timeout(rt_expires))
2554 			rt_expires *= HZ;
2555 
2556 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2557 					       pinfo->prefix_len,
2558 					       dev,
2559 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2560 					       RTF_GATEWAY | RTF_DEFAULT);
2561 
2562 		if (rt) {
2563 			/* Autoconf prefix route */
2564 			if (valid_lft == 0) {
2565 				ip6_del_rt(rt);
2566 				rt = NULL;
2567 			} else if (addrconf_finite_timeout(rt_expires)) {
2568 				/* not infinity */
2569 				rt6_set_expires(rt, jiffies + rt_expires);
2570 			} else {
2571 				rt6_clean_expires(rt);
2572 			}
2573 		} else if (valid_lft) {
2574 			clock_t expires = 0;
2575 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2576 			if (addrconf_finite_timeout(rt_expires)) {
2577 				/* not infinity */
2578 				flags |= RTF_EXPIRES;
2579 				expires = jiffies_to_clock_t(rt_expires);
2580 			}
2581 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2582 					      dev, expires, flags);
2583 		}
2584 		ip6_rt_put(rt);
2585 	}
2586 
2587 	/* Try to figure out our local address for this prefix */
2588 
2589 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
2590 		struct in6_addr addr;
2591 		bool tokenized = false, dev_addr_generated = false;
2592 
2593 		if (pinfo->prefix_len == 64) {
2594 			memcpy(&addr, &pinfo->prefix, 8);
2595 
2596 			if (!ipv6_addr_any(&in6_dev->token)) {
2597 				read_lock_bh(&in6_dev->lock);
2598 				memcpy(addr.s6_addr + 8,
2599 				       in6_dev->token.s6_addr + 8, 8);
2600 				read_unlock_bh(&in6_dev->lock);
2601 				tokenized = true;
2602 			} else if (is_addr_mode_generate_stable(in6_dev) &&
2603 				   !ipv6_generate_stable_address(&addr, 0,
2604 								 in6_dev)) {
2605 				addr_flags |= IFA_F_STABLE_PRIVACY;
2606 				goto ok;
2607 			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2608 				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2609 				goto put;
2610 			} else {
2611 				dev_addr_generated = true;
2612 			}
2613 			goto ok;
2614 		}
2615 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2616 				    pinfo->prefix_len);
2617 		goto put;
2618 
2619 ok:
2620 		err = addrconf_prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
2621 						   &addr, addr_type,
2622 						   addr_flags, sllao,
2623 						   tokenized, valid_lft,
2624 						   prefered_lft);
2625 		if (err)
2626 			goto put;
2627 
2628 		/* Ignore error case here because previous prefix add addr was
2629 		 * successful which will be notified.
2630 		 */
2631 		ndisc_ops_prefix_rcv_add_addr(net, dev, pinfo, in6_dev, &addr,
2632 					      addr_type, addr_flags, sllao,
2633 					      tokenized, valid_lft,
2634 					      prefered_lft,
2635 					      dev_addr_generated);
2636 	}
2637 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2638 put:
2639 	in6_dev_put(in6_dev);
2640 }
2641 
2642 /*
2643  *	Set destination address.
2644  *	Special case for SIT interfaces where we create a new "virtual"
2645  *	device.
2646  */
2647 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2648 {
2649 	struct in6_ifreq ireq;
2650 	struct net_device *dev;
2651 	int err = -EINVAL;
2652 
2653 	rtnl_lock();
2654 
2655 	err = -EFAULT;
2656 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2657 		goto err_exit;
2658 
2659 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2660 
2661 	err = -ENODEV;
2662 	if (!dev)
2663 		goto err_exit;
2664 
2665 #if IS_ENABLED(CONFIG_IPV6_SIT)
2666 	if (dev->type == ARPHRD_SIT) {
2667 		const struct net_device_ops *ops = dev->netdev_ops;
2668 		struct ifreq ifr;
2669 		struct ip_tunnel_parm p;
2670 
2671 		err = -EADDRNOTAVAIL;
2672 		if (!(ipv6_addr_type(&ireq.ifr6_addr) & IPV6_ADDR_COMPATv4))
2673 			goto err_exit;
2674 
2675 		memset(&p, 0, sizeof(p));
2676 		p.iph.daddr = ireq.ifr6_addr.s6_addr32[3];
2677 		p.iph.saddr = 0;
2678 		p.iph.version = 4;
2679 		p.iph.ihl = 5;
2680 		p.iph.protocol = IPPROTO_IPV6;
2681 		p.iph.ttl = 64;
2682 		ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
2683 
2684 		if (ops->ndo_do_ioctl) {
2685 			mm_segment_t oldfs = get_fs();
2686 
2687 			set_fs(KERNEL_DS);
2688 			err = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
2689 			set_fs(oldfs);
2690 		} else
2691 			err = -EOPNOTSUPP;
2692 
2693 		if (err == 0) {
2694 			err = -ENOBUFS;
2695 			dev = __dev_get_by_name(net, p.name);
2696 			if (!dev)
2697 				goto err_exit;
2698 			err = dev_open(dev);
2699 		}
2700 	}
2701 #endif
2702 
2703 err_exit:
2704 	rtnl_unlock();
2705 	return err;
2706 }
2707 
2708 static int ipv6_mc_config(struct sock *sk, bool join,
2709 			  const struct in6_addr *addr, int ifindex)
2710 {
2711 	int ret;
2712 
2713 	ASSERT_RTNL();
2714 
2715 	lock_sock(sk);
2716 	if (join)
2717 		ret = ipv6_sock_mc_join(sk, ifindex, addr);
2718 	else
2719 		ret = ipv6_sock_mc_drop(sk, ifindex, addr);
2720 	release_sock(sk);
2721 
2722 	return ret;
2723 }
2724 
2725 /*
2726  *	Manual configuration of address on an interface
2727  */
2728 static int inet6_addr_add(struct net *net, int ifindex,
2729 			  const struct in6_addr *pfx,
2730 			  const struct in6_addr *peer_pfx,
2731 			  unsigned int plen, __u32 ifa_flags,
2732 			  __u32 prefered_lft, __u32 valid_lft)
2733 {
2734 	struct inet6_ifaddr *ifp;
2735 	struct inet6_dev *idev;
2736 	struct net_device *dev;
2737 	unsigned long timeout;
2738 	clock_t expires;
2739 	int scope;
2740 	u32 flags;
2741 
2742 	ASSERT_RTNL();
2743 
2744 	if (plen > 128)
2745 		return -EINVAL;
2746 
2747 	/* check the lifetime */
2748 	if (!valid_lft || prefered_lft > valid_lft)
2749 		return -EINVAL;
2750 
2751 	if (ifa_flags & IFA_F_MANAGETEMPADDR && plen != 64)
2752 		return -EINVAL;
2753 
2754 	dev = __dev_get_by_index(net, ifindex);
2755 	if (!dev)
2756 		return -ENODEV;
2757 
2758 	idev = addrconf_add_dev(dev);
2759 	if (IS_ERR(idev))
2760 		return PTR_ERR(idev);
2761 
2762 	if (ifa_flags & IFA_F_MCAUTOJOIN) {
2763 		int ret = ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2764 					 true, pfx, ifindex);
2765 
2766 		if (ret < 0)
2767 			return ret;
2768 	}
2769 
2770 	scope = ipv6_addr_scope(pfx);
2771 
2772 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
2773 	if (addrconf_finite_timeout(timeout)) {
2774 		expires = jiffies_to_clock_t(timeout * HZ);
2775 		valid_lft = timeout;
2776 		flags = RTF_EXPIRES;
2777 	} else {
2778 		expires = 0;
2779 		flags = 0;
2780 		ifa_flags |= IFA_F_PERMANENT;
2781 	}
2782 
2783 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
2784 	if (addrconf_finite_timeout(timeout)) {
2785 		if (timeout == 0)
2786 			ifa_flags |= IFA_F_DEPRECATED;
2787 		prefered_lft = timeout;
2788 	}
2789 
2790 	ifp = ipv6_add_addr(idev, pfx, peer_pfx, plen, scope, ifa_flags,
2791 			    valid_lft, prefered_lft);
2792 
2793 	if (!IS_ERR(ifp)) {
2794 		if (!(ifa_flags & IFA_F_NOPREFIXROUTE)) {
2795 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len, dev,
2796 					      expires, flags);
2797 		}
2798 
2799 		/*
2800 		 * Note that section 3.1 of RFC 4429 indicates
2801 		 * that the Optimistic flag should not be set for
2802 		 * manually configured addresses
2803 		 */
2804 		addrconf_dad_start(ifp);
2805 		if (ifa_flags & IFA_F_MANAGETEMPADDR)
2806 			manage_tempaddrs(idev, ifp, valid_lft, prefered_lft,
2807 					 true, jiffies);
2808 		in6_ifa_put(ifp);
2809 		addrconf_verify_rtnl();
2810 		return 0;
2811 	} else if (ifa_flags & IFA_F_MCAUTOJOIN) {
2812 		ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2813 			       false, pfx, ifindex);
2814 	}
2815 
2816 	return PTR_ERR(ifp);
2817 }
2818 
2819 static int inet6_addr_del(struct net *net, int ifindex, u32 ifa_flags,
2820 			  const struct in6_addr *pfx, unsigned int plen)
2821 {
2822 	struct inet6_ifaddr *ifp;
2823 	struct inet6_dev *idev;
2824 	struct net_device *dev;
2825 
2826 	if (plen > 128)
2827 		return -EINVAL;
2828 
2829 	dev = __dev_get_by_index(net, ifindex);
2830 	if (!dev)
2831 		return -ENODEV;
2832 
2833 	idev = __in6_dev_get(dev);
2834 	if (!idev)
2835 		return -ENXIO;
2836 
2837 	read_lock_bh(&idev->lock);
2838 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
2839 		if (ifp->prefix_len == plen &&
2840 		    ipv6_addr_equal(pfx, &ifp->addr)) {
2841 			in6_ifa_hold(ifp);
2842 			read_unlock_bh(&idev->lock);
2843 
2844 			if (!(ifp->flags & IFA_F_TEMPORARY) &&
2845 			    (ifa_flags & IFA_F_MANAGETEMPADDR))
2846 				manage_tempaddrs(idev, ifp, 0, 0, false,
2847 						 jiffies);
2848 			ipv6_del_addr(ifp);
2849 			addrconf_verify_rtnl();
2850 			if (ipv6_addr_is_multicast(pfx)) {
2851 				ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2852 					       false, pfx, dev->ifindex);
2853 			}
2854 			return 0;
2855 		}
2856 	}
2857 	read_unlock_bh(&idev->lock);
2858 	return -EADDRNOTAVAIL;
2859 }
2860 
2861 
2862 int addrconf_add_ifaddr(struct net *net, void __user *arg)
2863 {
2864 	struct in6_ifreq ireq;
2865 	int err;
2866 
2867 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2868 		return -EPERM;
2869 
2870 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2871 		return -EFAULT;
2872 
2873 	rtnl_lock();
2874 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &ireq.ifr6_addr, NULL,
2875 			     ireq.ifr6_prefixlen, IFA_F_PERMANENT,
2876 			     INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
2877 	rtnl_unlock();
2878 	return err;
2879 }
2880 
2881 int addrconf_del_ifaddr(struct net *net, void __user *arg)
2882 {
2883 	struct in6_ifreq ireq;
2884 	int err;
2885 
2886 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2887 		return -EPERM;
2888 
2889 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2890 		return -EFAULT;
2891 
2892 	rtnl_lock();
2893 	err = inet6_addr_del(net, ireq.ifr6_ifindex, 0, &ireq.ifr6_addr,
2894 			     ireq.ifr6_prefixlen);
2895 	rtnl_unlock();
2896 	return err;
2897 }
2898 
2899 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
2900 		     int plen, int scope)
2901 {
2902 	struct inet6_ifaddr *ifp;
2903 
2904 	ifp = ipv6_add_addr(idev, addr, NULL, plen,
2905 			    scope, IFA_F_PERMANENT,
2906 			    INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
2907 	if (!IS_ERR(ifp)) {
2908 		spin_lock_bh(&ifp->lock);
2909 		ifp->flags &= ~IFA_F_TENTATIVE;
2910 		spin_unlock_bh(&ifp->lock);
2911 		rt_genid_bump_ipv6(dev_net(idev->dev));
2912 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
2913 		in6_ifa_put(ifp);
2914 	}
2915 }
2916 
2917 #if IS_ENABLED(CONFIG_IPV6_SIT)
2918 static void sit_add_v4_addrs(struct inet6_dev *idev)
2919 {
2920 	struct in6_addr addr;
2921 	struct net_device *dev;
2922 	struct net *net = dev_net(idev->dev);
2923 	int scope, plen;
2924 	u32 pflags = 0;
2925 
2926 	ASSERT_RTNL();
2927 
2928 	memset(&addr, 0, sizeof(struct in6_addr));
2929 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
2930 
2931 	if (idev->dev->flags&IFF_POINTOPOINT) {
2932 		addr.s6_addr32[0] = htonl(0xfe800000);
2933 		scope = IFA_LINK;
2934 		plen = 64;
2935 	} else {
2936 		scope = IPV6_ADDR_COMPATv4;
2937 		plen = 96;
2938 		pflags |= RTF_NONEXTHOP;
2939 	}
2940 
2941 	if (addr.s6_addr32[3]) {
2942 		add_addr(idev, &addr, plen, scope);
2943 		addrconf_prefix_route(&addr, plen, idev->dev, 0, pflags);
2944 		return;
2945 	}
2946 
2947 	for_each_netdev(net, dev) {
2948 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
2949 		if (in_dev && (dev->flags & IFF_UP)) {
2950 			struct in_ifaddr *ifa;
2951 
2952 			int flag = scope;
2953 
2954 			for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
2955 
2956 				addr.s6_addr32[3] = ifa->ifa_local;
2957 
2958 				if (ifa->ifa_scope == RT_SCOPE_LINK)
2959 					continue;
2960 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
2961 					if (idev->dev->flags&IFF_POINTOPOINT)
2962 						continue;
2963 					flag |= IFA_HOST;
2964 				}
2965 
2966 				add_addr(idev, &addr, plen, flag);
2967 				addrconf_prefix_route(&addr, plen, idev->dev, 0,
2968 						      pflags);
2969 			}
2970 		}
2971 	}
2972 }
2973 #endif
2974 
2975 static void init_loopback(struct net_device *dev)
2976 {
2977 	struct inet6_dev  *idev;
2978 	struct net_device *sp_dev;
2979 	struct inet6_ifaddr *sp_ifa;
2980 	struct rt6_info *sp_rt;
2981 
2982 	/* ::1 */
2983 
2984 	ASSERT_RTNL();
2985 
2986 	idev = ipv6_find_idev(dev);
2987 	if (!idev) {
2988 		pr_debug("%s: add_dev failed\n", __func__);
2989 		return;
2990 	}
2991 
2992 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST);
2993 
2994 	/* Add routes to other interface's IPv6 addresses */
2995 	for_each_netdev(dev_net(dev), sp_dev) {
2996 		if (!strcmp(sp_dev->name, dev->name))
2997 			continue;
2998 
2999 		idev = __in6_dev_get(sp_dev);
3000 		if (!idev)
3001 			continue;
3002 
3003 		read_lock_bh(&idev->lock);
3004 		list_for_each_entry(sp_ifa, &idev->addr_list, if_list) {
3005 
3006 			if (sp_ifa->flags & (IFA_F_DADFAILED | IFA_F_TENTATIVE))
3007 				continue;
3008 
3009 			if (sp_ifa->rt) {
3010 				/* This dst has been added to garbage list when
3011 				 * lo device down, release this obsolete dst and
3012 				 * reallocate a new router for ifa.
3013 				 */
3014 				if (!atomic_read(&sp_ifa->rt->rt6i_ref)) {
3015 					ip6_rt_put(sp_ifa->rt);
3016 					sp_ifa->rt = NULL;
3017 				} else {
3018 					continue;
3019 				}
3020 			}
3021 
3022 			sp_rt = addrconf_dst_alloc(idev, &sp_ifa->addr, false);
3023 
3024 			/* Failure cases are ignored */
3025 			if (!IS_ERR(sp_rt)) {
3026 				sp_ifa->rt = sp_rt;
3027 				ip6_ins_rt(sp_rt);
3028 			}
3029 		}
3030 		read_unlock_bh(&idev->lock);
3031 	}
3032 }
3033 
3034 void addrconf_add_linklocal(struct inet6_dev *idev,
3035 			    const struct in6_addr *addr, u32 flags)
3036 {
3037 	struct inet6_ifaddr *ifp;
3038 	u32 addr_flags = flags | IFA_F_PERMANENT;
3039 
3040 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
3041 	if (idev->cnf.optimistic_dad &&
3042 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
3043 		addr_flags |= IFA_F_OPTIMISTIC;
3044 #endif
3045 
3046 	ifp = ipv6_add_addr(idev, addr, NULL, 64, IFA_LINK, addr_flags,
3047 			    INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
3048 	if (!IS_ERR(ifp)) {
3049 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, idev->dev, 0, 0);
3050 		addrconf_dad_start(ifp);
3051 		in6_ifa_put(ifp);
3052 	}
3053 }
3054 EXPORT_SYMBOL_GPL(addrconf_add_linklocal);
3055 
3056 static bool ipv6_reserved_interfaceid(struct in6_addr address)
3057 {
3058 	if ((address.s6_addr32[2] | address.s6_addr32[3]) == 0)
3059 		return true;
3060 
3061 	if (address.s6_addr32[2] == htonl(0x02005eff) &&
3062 	    ((address.s6_addr32[3] & htonl(0xfe000000)) == htonl(0xfe000000)))
3063 		return true;
3064 
3065 	if (address.s6_addr32[2] == htonl(0xfdffffff) &&
3066 	    ((address.s6_addr32[3] & htonl(0xffffff80)) == htonl(0xffffff80)))
3067 		return true;
3068 
3069 	return false;
3070 }
3071 
3072 static int ipv6_generate_stable_address(struct in6_addr *address,
3073 					u8 dad_count,
3074 					const struct inet6_dev *idev)
3075 {
3076 	static DEFINE_SPINLOCK(lock);
3077 	static __u32 digest[SHA_DIGEST_WORDS];
3078 	static __u32 workspace[SHA_WORKSPACE_WORDS];
3079 
3080 	static union {
3081 		char __data[SHA_MESSAGE_BYTES];
3082 		struct {
3083 			struct in6_addr secret;
3084 			__be32 prefix[2];
3085 			unsigned char hwaddr[MAX_ADDR_LEN];
3086 			u8 dad_count;
3087 		} __packed;
3088 	} data;
3089 
3090 	struct in6_addr secret;
3091 	struct in6_addr temp;
3092 	struct net *net = dev_net(idev->dev);
3093 
3094 	BUILD_BUG_ON(sizeof(data.__data) != sizeof(data));
3095 
3096 	if (idev->cnf.stable_secret.initialized)
3097 		secret = idev->cnf.stable_secret.secret;
3098 	else if (net->ipv6.devconf_dflt->stable_secret.initialized)
3099 		secret = net->ipv6.devconf_dflt->stable_secret.secret;
3100 	else
3101 		return -1;
3102 
3103 retry:
3104 	spin_lock_bh(&lock);
3105 
3106 	sha_init(digest);
3107 	memset(&data, 0, sizeof(data));
3108 	memset(workspace, 0, sizeof(workspace));
3109 	memcpy(data.hwaddr, idev->dev->perm_addr, idev->dev->addr_len);
3110 	data.prefix[0] = address->s6_addr32[0];
3111 	data.prefix[1] = address->s6_addr32[1];
3112 	data.secret = secret;
3113 	data.dad_count = dad_count;
3114 
3115 	sha_transform(digest, data.__data, workspace);
3116 
3117 	temp = *address;
3118 	temp.s6_addr32[2] = (__force __be32)digest[0];
3119 	temp.s6_addr32[3] = (__force __be32)digest[1];
3120 
3121 	spin_unlock_bh(&lock);
3122 
3123 	if (ipv6_reserved_interfaceid(temp)) {
3124 		dad_count++;
3125 		if (dad_count > dev_net(idev->dev)->ipv6.sysctl.idgen_retries)
3126 			return -1;
3127 		goto retry;
3128 	}
3129 
3130 	*address = temp;
3131 	return 0;
3132 }
3133 
3134 static void ipv6_gen_mode_random_init(struct inet6_dev *idev)
3135 {
3136 	struct ipv6_stable_secret *s = &idev->cnf.stable_secret;
3137 
3138 	if (s->initialized)
3139 		return;
3140 	s = &idev->cnf.stable_secret;
3141 	get_random_bytes(&s->secret, sizeof(s->secret));
3142 	s->initialized = true;
3143 }
3144 
3145 static void addrconf_addr_gen(struct inet6_dev *idev, bool prefix_route)
3146 {
3147 	struct in6_addr addr;
3148 
3149 	/* no link local addresses on L3 master devices */
3150 	if (netif_is_l3_master(idev->dev))
3151 		return;
3152 
3153 	ipv6_addr_set(&addr, htonl(0xFE800000), 0, 0, 0);
3154 
3155 	switch (idev->addr_gen_mode) {
3156 	case IN6_ADDR_GEN_MODE_RANDOM:
3157 		ipv6_gen_mode_random_init(idev);
3158 		/* fallthrough */
3159 	case IN6_ADDR_GEN_MODE_STABLE_PRIVACY:
3160 		if (!ipv6_generate_stable_address(&addr, 0, idev))
3161 			addrconf_add_linklocal(idev, &addr,
3162 					       IFA_F_STABLE_PRIVACY);
3163 		else if (prefix_route)
3164 			addrconf_prefix_route(&addr, 64, idev->dev, 0, 0);
3165 		break;
3166 	case IN6_ADDR_GEN_MODE_EUI64:
3167 		/* addrconf_add_linklocal also adds a prefix_route and we
3168 		 * only need to care about prefix routes if ipv6_generate_eui64
3169 		 * couldn't generate one.
3170 		 */
3171 		if (ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) == 0)
3172 			addrconf_add_linklocal(idev, &addr, 0);
3173 		else if (prefix_route)
3174 			addrconf_prefix_route(&addr, 64, idev->dev, 0, 0);
3175 		break;
3176 	case IN6_ADDR_GEN_MODE_NONE:
3177 	default:
3178 		/* will not add any link local address */
3179 		break;
3180 	}
3181 }
3182 
3183 static void addrconf_dev_config(struct net_device *dev)
3184 {
3185 	struct inet6_dev *idev;
3186 
3187 	ASSERT_RTNL();
3188 
3189 	if ((dev->type != ARPHRD_ETHER) &&
3190 	    (dev->type != ARPHRD_FDDI) &&
3191 	    (dev->type != ARPHRD_ARCNET) &&
3192 	    (dev->type != ARPHRD_INFINIBAND) &&
3193 	    (dev->type != ARPHRD_IEEE1394) &&
3194 	    (dev->type != ARPHRD_TUNNEL6) &&
3195 	    (dev->type != ARPHRD_6LOWPAN) &&
3196 	    (dev->type != ARPHRD_NONE)) {
3197 		/* Alas, we support only Ethernet autoconfiguration. */
3198 		return;
3199 	}
3200 
3201 	idev = addrconf_add_dev(dev);
3202 	if (IS_ERR(idev))
3203 		return;
3204 
3205 	/* this device type has no EUI support */
3206 	if (dev->type == ARPHRD_NONE &&
3207 	    idev->addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64)
3208 		idev->addr_gen_mode = IN6_ADDR_GEN_MODE_RANDOM;
3209 
3210 	addrconf_addr_gen(idev, false);
3211 }
3212 
3213 #if IS_ENABLED(CONFIG_IPV6_SIT)
3214 static void addrconf_sit_config(struct net_device *dev)
3215 {
3216 	struct inet6_dev *idev;
3217 
3218 	ASSERT_RTNL();
3219 
3220 	/*
3221 	 * Configure the tunnel with one of our IPv4
3222 	 * addresses... we should configure all of
3223 	 * our v4 addrs in the tunnel
3224 	 */
3225 
3226 	idev = ipv6_find_idev(dev);
3227 	if (!idev) {
3228 		pr_debug("%s: add_dev failed\n", __func__);
3229 		return;
3230 	}
3231 
3232 	if (dev->priv_flags & IFF_ISATAP) {
3233 		addrconf_addr_gen(idev, false);
3234 		return;
3235 	}
3236 
3237 	sit_add_v4_addrs(idev);
3238 
3239 	if (dev->flags&IFF_POINTOPOINT)
3240 		addrconf_add_mroute(dev);
3241 }
3242 #endif
3243 
3244 #if IS_ENABLED(CONFIG_NET_IPGRE)
3245 static void addrconf_gre_config(struct net_device *dev)
3246 {
3247 	struct inet6_dev *idev;
3248 
3249 	ASSERT_RTNL();
3250 
3251 	idev = ipv6_find_idev(dev);
3252 	if (!idev) {
3253 		pr_debug("%s: add_dev failed\n", __func__);
3254 		return;
3255 	}
3256 
3257 	addrconf_addr_gen(idev, true);
3258 	if (dev->flags & IFF_POINTOPOINT)
3259 		addrconf_add_mroute(dev);
3260 }
3261 #endif
3262 
3263 static int fixup_permanent_addr(struct inet6_dev *idev,
3264 				struct inet6_ifaddr *ifp)
3265 {
3266 	if (!ifp->rt) {
3267 		struct rt6_info *rt;
3268 
3269 		rt = addrconf_dst_alloc(idev, &ifp->addr, false);
3270 		if (unlikely(IS_ERR(rt)))
3271 			return PTR_ERR(rt);
3272 
3273 		ifp->rt = rt;
3274 	}
3275 
3276 	if (!(ifp->flags & IFA_F_NOPREFIXROUTE)) {
3277 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3278 				      idev->dev, 0, 0);
3279 	}
3280 
3281 	addrconf_dad_start(ifp);
3282 
3283 	return 0;
3284 }
3285 
3286 static void addrconf_permanent_addr(struct net_device *dev)
3287 {
3288 	struct inet6_ifaddr *ifp, *tmp;
3289 	struct inet6_dev *idev;
3290 
3291 	idev = __in6_dev_get(dev);
3292 	if (!idev)
3293 		return;
3294 
3295 	write_lock_bh(&idev->lock);
3296 
3297 	list_for_each_entry_safe(ifp, tmp, &idev->addr_list, if_list) {
3298 		if ((ifp->flags & IFA_F_PERMANENT) &&
3299 		    fixup_permanent_addr(idev, ifp) < 0) {
3300 			write_unlock_bh(&idev->lock);
3301 			ipv6_del_addr(ifp);
3302 			write_lock_bh(&idev->lock);
3303 
3304 			net_info_ratelimited("%s: Failed to add prefix route for address %pI6c; dropping\n",
3305 					     idev->dev->name, &ifp->addr);
3306 		}
3307 	}
3308 
3309 	write_unlock_bh(&idev->lock);
3310 }
3311 
3312 static int addrconf_notify(struct notifier_block *this, unsigned long event,
3313 			   void *ptr)
3314 {
3315 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3316 	struct netdev_notifier_changeupper_info *info;
3317 	struct inet6_dev *idev = __in6_dev_get(dev);
3318 	int run_pending = 0;
3319 	int err;
3320 
3321 	switch (event) {
3322 	case NETDEV_REGISTER:
3323 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
3324 			idev = ipv6_add_dev(dev);
3325 			if (IS_ERR(idev))
3326 				return notifier_from_errno(PTR_ERR(idev));
3327 		}
3328 		break;
3329 
3330 	case NETDEV_CHANGEMTU:
3331 		/* if MTU under IPV6_MIN_MTU stop IPv6 on this interface. */
3332 		if (dev->mtu < IPV6_MIN_MTU) {
3333 			addrconf_ifdown(dev, 1);
3334 			break;
3335 		}
3336 
3337 		if (idev) {
3338 			rt6_mtu_change(dev, dev->mtu);
3339 			idev->cnf.mtu6 = dev->mtu;
3340 			break;
3341 		}
3342 
3343 		/* allocate new idev */
3344 		idev = ipv6_add_dev(dev);
3345 		if (IS_ERR(idev))
3346 			break;
3347 
3348 		/* device is still not ready */
3349 		if (!(idev->if_flags & IF_READY))
3350 			break;
3351 
3352 		run_pending = 1;
3353 
3354 		/* fall through */
3355 
3356 	case NETDEV_UP:
3357 	case NETDEV_CHANGE:
3358 		if (dev->flags & IFF_SLAVE)
3359 			break;
3360 
3361 		if (idev && idev->cnf.disable_ipv6)
3362 			break;
3363 
3364 		if (event == NETDEV_UP) {
3365 			/* restore routes for permanent addresses */
3366 			addrconf_permanent_addr(dev);
3367 
3368 			if (!addrconf_qdisc_ok(dev)) {
3369 				/* device is not ready yet. */
3370 				pr_info("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
3371 					dev->name);
3372 				break;
3373 			}
3374 
3375 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
3376 				idev = ipv6_add_dev(dev);
3377 
3378 			if (!IS_ERR_OR_NULL(idev)) {
3379 				idev->if_flags |= IF_READY;
3380 				run_pending = 1;
3381 			}
3382 		} else if (event == NETDEV_CHANGE) {
3383 			if (!addrconf_qdisc_ok(dev)) {
3384 				/* device is still not ready. */
3385 				break;
3386 			}
3387 
3388 			if (idev) {
3389 				if (idev->if_flags & IF_READY) {
3390 					/* device is already configured -
3391 					 * but resend MLD reports, we might
3392 					 * have roamed and need to update
3393 					 * multicast snooping switches
3394 					 */
3395 					ipv6_mc_up(idev);
3396 					break;
3397 				}
3398 				idev->if_flags |= IF_READY;
3399 			}
3400 
3401 			pr_info("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
3402 				dev->name);
3403 
3404 			run_pending = 1;
3405 		}
3406 
3407 		switch (dev->type) {
3408 #if IS_ENABLED(CONFIG_IPV6_SIT)
3409 		case ARPHRD_SIT:
3410 			addrconf_sit_config(dev);
3411 			break;
3412 #endif
3413 #if IS_ENABLED(CONFIG_NET_IPGRE)
3414 		case ARPHRD_IPGRE:
3415 			addrconf_gre_config(dev);
3416 			break;
3417 #endif
3418 		case ARPHRD_LOOPBACK:
3419 			init_loopback(dev);
3420 			break;
3421 
3422 		default:
3423 			addrconf_dev_config(dev);
3424 			break;
3425 		}
3426 
3427 		if (!IS_ERR_OR_NULL(idev)) {
3428 			if (run_pending)
3429 				addrconf_dad_run(idev);
3430 
3431 			/*
3432 			 * If the MTU changed during the interface down,
3433 			 * when the interface up, the changed MTU must be
3434 			 * reflected in the idev as well as routers.
3435 			 */
3436 			if (idev->cnf.mtu6 != dev->mtu &&
3437 			    dev->mtu >= IPV6_MIN_MTU) {
3438 				rt6_mtu_change(dev, dev->mtu);
3439 				idev->cnf.mtu6 = dev->mtu;
3440 			}
3441 			idev->tstamp = jiffies;
3442 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
3443 
3444 			/*
3445 			 * If the changed mtu during down is lower than
3446 			 * IPV6_MIN_MTU stop IPv6 on this interface.
3447 			 */
3448 			if (dev->mtu < IPV6_MIN_MTU)
3449 				addrconf_ifdown(dev, 1);
3450 		}
3451 		break;
3452 
3453 	case NETDEV_DOWN:
3454 	case NETDEV_UNREGISTER:
3455 		/*
3456 		 *	Remove all addresses from this interface.
3457 		 */
3458 		addrconf_ifdown(dev, event != NETDEV_DOWN);
3459 		break;
3460 
3461 	case NETDEV_CHANGENAME:
3462 		if (idev) {
3463 			snmp6_unregister_dev(idev);
3464 			addrconf_sysctl_unregister(idev);
3465 			err = addrconf_sysctl_register(idev);
3466 			if (err)
3467 				return notifier_from_errno(err);
3468 			err = snmp6_register_dev(idev);
3469 			if (err) {
3470 				addrconf_sysctl_unregister(idev);
3471 				return notifier_from_errno(err);
3472 			}
3473 		}
3474 		break;
3475 
3476 	case NETDEV_PRE_TYPE_CHANGE:
3477 	case NETDEV_POST_TYPE_CHANGE:
3478 		if (idev)
3479 			addrconf_type_change(dev, event);
3480 		break;
3481 
3482 	case NETDEV_CHANGEUPPER:
3483 		info = ptr;
3484 
3485 		/* flush all routes if dev is linked to or unlinked from
3486 		 * an L3 master device (e.g., VRF)
3487 		 */
3488 		if (info->upper_dev && netif_is_l3_master(info->upper_dev))
3489 			addrconf_ifdown(dev, 0);
3490 	}
3491 
3492 	return NOTIFY_OK;
3493 }
3494 
3495 /*
3496  *	addrconf module should be notified of a device going up
3497  */
3498 static struct notifier_block ipv6_dev_notf = {
3499 	.notifier_call = addrconf_notify,
3500 };
3501 
3502 static void addrconf_type_change(struct net_device *dev, unsigned long event)
3503 {
3504 	struct inet6_dev *idev;
3505 	ASSERT_RTNL();
3506 
3507 	idev = __in6_dev_get(dev);
3508 
3509 	if (event == NETDEV_POST_TYPE_CHANGE)
3510 		ipv6_mc_remap(idev);
3511 	else if (event == NETDEV_PRE_TYPE_CHANGE)
3512 		ipv6_mc_unmap(idev);
3513 }
3514 
3515 static bool addr_is_local(const struct in6_addr *addr)
3516 {
3517 	return ipv6_addr_type(addr) &
3518 		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
3519 }
3520 
3521 static int addrconf_ifdown(struct net_device *dev, int how)
3522 {
3523 	struct net *net = dev_net(dev);
3524 	struct inet6_dev *idev;
3525 	struct inet6_ifaddr *ifa, *tmp;
3526 	struct list_head del_list;
3527 	int _keep_addr;
3528 	bool keep_addr;
3529 	int state, i;
3530 
3531 	ASSERT_RTNL();
3532 
3533 	rt6_ifdown(net, dev);
3534 	neigh_ifdown(&nd_tbl, dev);
3535 
3536 	idev = __in6_dev_get(dev);
3537 	if (!idev)
3538 		return -ENODEV;
3539 
3540 	/*
3541 	 * Step 1: remove reference to ipv6 device from parent device.
3542 	 *	   Do not dev_put!
3543 	 */
3544 	if (how) {
3545 		idev->dead = 1;
3546 
3547 		/* protected by rtnl_lock */
3548 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
3549 
3550 		/* Step 1.5: remove snmp6 entry */
3551 		snmp6_unregister_dev(idev);
3552 
3553 	}
3554 
3555 	/* aggregate the system setting and interface setting */
3556 	_keep_addr = net->ipv6.devconf_all->keep_addr_on_down;
3557 	if (!_keep_addr)
3558 		_keep_addr = idev->cnf.keep_addr_on_down;
3559 
3560 	/* combine the user config with event to determine if permanent
3561 	 * addresses are to be removed from address hash table
3562 	 */
3563 	keep_addr = !(how || _keep_addr <= 0 || idev->cnf.disable_ipv6);
3564 
3565 	/* Step 2: clear hash table */
3566 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3567 		struct hlist_head *h = &inet6_addr_lst[i];
3568 
3569 		spin_lock_bh(&addrconf_hash_lock);
3570 restart:
3571 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
3572 			if (ifa->idev == idev) {
3573 				addrconf_del_dad_work(ifa);
3574 				/* combined flag + permanent flag decide if
3575 				 * address is retained on a down event
3576 				 */
3577 				if (!keep_addr ||
3578 				    !(ifa->flags & IFA_F_PERMANENT) ||
3579 				    addr_is_local(&ifa->addr)) {
3580 					hlist_del_init_rcu(&ifa->addr_lst);
3581 					goto restart;
3582 				}
3583 			}
3584 		}
3585 		spin_unlock_bh(&addrconf_hash_lock);
3586 	}
3587 
3588 	write_lock_bh(&idev->lock);
3589 
3590 	addrconf_del_rs_timer(idev);
3591 
3592 	/* Step 2: clear flags for stateless addrconf */
3593 	if (!how)
3594 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3595 
3596 	/* Step 3: clear tempaddr list */
3597 	while (!list_empty(&idev->tempaddr_list)) {
3598 		ifa = list_first_entry(&idev->tempaddr_list,
3599 				       struct inet6_ifaddr, tmp_list);
3600 		list_del(&ifa->tmp_list);
3601 		write_unlock_bh(&idev->lock);
3602 		spin_lock_bh(&ifa->lock);
3603 
3604 		if (ifa->ifpub) {
3605 			in6_ifa_put(ifa->ifpub);
3606 			ifa->ifpub = NULL;
3607 		}
3608 		spin_unlock_bh(&ifa->lock);
3609 		in6_ifa_put(ifa);
3610 		write_lock_bh(&idev->lock);
3611 	}
3612 
3613 	/* re-combine the user config with event to determine if permanent
3614 	 * addresses are to be removed from the interface list
3615 	 */
3616 	keep_addr = (!how && _keep_addr > 0 && !idev->cnf.disable_ipv6);
3617 
3618 	INIT_LIST_HEAD(&del_list);
3619 	list_for_each_entry_safe(ifa, tmp, &idev->addr_list, if_list) {
3620 		struct rt6_info *rt = NULL;
3621 
3622 		addrconf_del_dad_work(ifa);
3623 
3624 		write_unlock_bh(&idev->lock);
3625 		spin_lock_bh(&ifa->lock);
3626 
3627 		if (keep_addr && (ifa->flags & IFA_F_PERMANENT) &&
3628 		    !addr_is_local(&ifa->addr)) {
3629 			/* set state to skip the notifier below */
3630 			state = INET6_IFADDR_STATE_DEAD;
3631 			ifa->state = 0;
3632 			if (!(ifa->flags & IFA_F_NODAD))
3633 				ifa->flags |= IFA_F_TENTATIVE;
3634 
3635 			rt = ifa->rt;
3636 			ifa->rt = NULL;
3637 		} else {
3638 			state = ifa->state;
3639 			ifa->state = INET6_IFADDR_STATE_DEAD;
3640 
3641 			list_move(&ifa->if_list, &del_list);
3642 		}
3643 
3644 		spin_unlock_bh(&ifa->lock);
3645 
3646 		if (rt)
3647 			ip6_del_rt(rt);
3648 
3649 		if (state != INET6_IFADDR_STATE_DEAD) {
3650 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
3651 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
3652 		} else {
3653 			if (idev->cnf.forwarding)
3654 				addrconf_leave_anycast(ifa);
3655 			addrconf_leave_solict(ifa->idev, &ifa->addr);
3656 		}
3657 
3658 		write_lock_bh(&idev->lock);
3659 	}
3660 
3661 	write_unlock_bh(&idev->lock);
3662 
3663 	/* now clean up addresses to be removed */
3664 	while (!list_empty(&del_list)) {
3665 		ifa = list_first_entry(&del_list,
3666 				       struct inet6_ifaddr, if_list);
3667 		list_del(&ifa->if_list);
3668 
3669 		in6_ifa_put(ifa);
3670 	}
3671 
3672 	/* Step 5: Discard anycast and multicast list */
3673 	if (how) {
3674 		ipv6_ac_destroy_dev(idev);
3675 		ipv6_mc_destroy_dev(idev);
3676 	} else {
3677 		ipv6_mc_down(idev);
3678 	}
3679 
3680 	idev->tstamp = jiffies;
3681 
3682 	/* Last: Shot the device (if unregistered) */
3683 	if (how) {
3684 		addrconf_sysctl_unregister(idev);
3685 		neigh_parms_release(&nd_tbl, idev->nd_parms);
3686 		neigh_ifdown(&nd_tbl, dev);
3687 		in6_dev_put(idev);
3688 	}
3689 	return 0;
3690 }
3691 
3692 static void addrconf_rs_timer(unsigned long data)
3693 {
3694 	struct inet6_dev *idev = (struct inet6_dev *)data;
3695 	struct net_device *dev = idev->dev;
3696 	struct in6_addr lladdr;
3697 
3698 	write_lock(&idev->lock);
3699 	if (idev->dead || !(idev->if_flags & IF_READY))
3700 		goto out;
3701 
3702 	if (!ipv6_accept_ra(idev))
3703 		goto out;
3704 
3705 	/* Announcement received after solicitation was sent */
3706 	if (idev->if_flags & IF_RA_RCVD)
3707 		goto out;
3708 
3709 	if (idev->rs_probes++ < idev->cnf.rtr_solicits || idev->cnf.rtr_solicits < 0) {
3710 		write_unlock(&idev->lock);
3711 		if (!ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
3712 			ndisc_send_rs(dev, &lladdr,
3713 				      &in6addr_linklocal_allrouters);
3714 		else
3715 			goto put;
3716 
3717 		write_lock(&idev->lock);
3718 		idev->rs_interval = rfc3315_s14_backoff_update(
3719 			idev->rs_interval, idev->cnf.rtr_solicit_max_interval);
3720 		/* The wait after the last probe can be shorter */
3721 		addrconf_mod_rs_timer(idev, (idev->rs_probes ==
3722 					     idev->cnf.rtr_solicits) ?
3723 				      idev->cnf.rtr_solicit_delay :
3724 				      idev->rs_interval);
3725 	} else {
3726 		/*
3727 		 * Note: we do not support deprecated "all on-link"
3728 		 * assumption any longer.
3729 		 */
3730 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
3731 	}
3732 
3733 out:
3734 	write_unlock(&idev->lock);
3735 put:
3736 	in6_dev_put(idev);
3737 }
3738 
3739 /*
3740  *	Duplicate Address Detection
3741  */
3742 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
3743 {
3744 	unsigned long rand_num;
3745 	struct inet6_dev *idev = ifp->idev;
3746 	u64 nonce;
3747 
3748 	if (ifp->flags & IFA_F_OPTIMISTIC)
3749 		rand_num = 0;
3750 	else
3751 		rand_num = prandom_u32() % (idev->cnf.rtr_solicit_delay ? : 1);
3752 
3753 	nonce = 0;
3754 	if (idev->cnf.enhanced_dad ||
3755 	    dev_net(idev->dev)->ipv6.devconf_all->enhanced_dad) {
3756 		do
3757 			get_random_bytes(&nonce, 6);
3758 		while (nonce == 0);
3759 	}
3760 	ifp->dad_nonce = nonce;
3761 	ifp->dad_probes = idev->cnf.dad_transmits;
3762 	addrconf_mod_dad_work(ifp, rand_num);
3763 }
3764 
3765 static void addrconf_dad_begin(struct inet6_ifaddr *ifp)
3766 {
3767 	struct inet6_dev *idev = ifp->idev;
3768 	struct net_device *dev = idev->dev;
3769 	bool bump_id, notify = false;
3770 
3771 	addrconf_join_solict(dev, &ifp->addr);
3772 
3773 	prandom_seed((__force u32) ifp->addr.s6_addr32[3]);
3774 
3775 	read_lock_bh(&idev->lock);
3776 	spin_lock(&ifp->lock);
3777 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
3778 		goto out;
3779 
3780 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
3781 	    idev->cnf.accept_dad < 1 ||
3782 	    !(ifp->flags&IFA_F_TENTATIVE) ||
3783 	    ifp->flags & IFA_F_NODAD) {
3784 		bump_id = ifp->flags & IFA_F_TENTATIVE;
3785 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3786 		spin_unlock(&ifp->lock);
3787 		read_unlock_bh(&idev->lock);
3788 
3789 		addrconf_dad_completed(ifp, bump_id);
3790 		return;
3791 	}
3792 
3793 	if (!(idev->if_flags & IF_READY)) {
3794 		spin_unlock(&ifp->lock);
3795 		read_unlock_bh(&idev->lock);
3796 		/*
3797 		 * If the device is not ready:
3798 		 * - keep it tentative if it is a permanent address.
3799 		 * - otherwise, kill it.
3800 		 */
3801 		in6_ifa_hold(ifp);
3802 		addrconf_dad_stop(ifp, 0);
3803 		return;
3804 	}
3805 
3806 	/*
3807 	 * Optimistic nodes can start receiving
3808 	 * Frames right away
3809 	 */
3810 	if (ifp->flags & IFA_F_OPTIMISTIC) {
3811 		ip6_ins_rt(ifp->rt);
3812 		if (ipv6_use_optimistic_addr(idev)) {
3813 			/* Because optimistic nodes can use this address,
3814 			 * notify listeners. If DAD fails, RTM_DELADDR is sent.
3815 			 */
3816 			notify = true;
3817 		}
3818 	}
3819 
3820 	addrconf_dad_kick(ifp);
3821 out:
3822 	spin_unlock(&ifp->lock);
3823 	read_unlock_bh(&idev->lock);
3824 	if (notify)
3825 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3826 }
3827 
3828 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
3829 {
3830 	bool begin_dad = false;
3831 
3832 	spin_lock_bh(&ifp->lock);
3833 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
3834 		ifp->state = INET6_IFADDR_STATE_PREDAD;
3835 		begin_dad = true;
3836 	}
3837 	spin_unlock_bh(&ifp->lock);
3838 
3839 	if (begin_dad)
3840 		addrconf_mod_dad_work(ifp, 0);
3841 }
3842 
3843 static void addrconf_dad_work(struct work_struct *w)
3844 {
3845 	struct inet6_ifaddr *ifp = container_of(to_delayed_work(w),
3846 						struct inet6_ifaddr,
3847 						dad_work);
3848 	struct inet6_dev *idev = ifp->idev;
3849 	bool bump_id, disable_ipv6 = false;
3850 	struct in6_addr mcaddr;
3851 
3852 	enum {
3853 		DAD_PROCESS,
3854 		DAD_BEGIN,
3855 		DAD_ABORT,
3856 	} action = DAD_PROCESS;
3857 
3858 	rtnl_lock();
3859 
3860 	spin_lock_bh(&ifp->lock);
3861 	if (ifp->state == INET6_IFADDR_STATE_PREDAD) {
3862 		action = DAD_BEGIN;
3863 		ifp->state = INET6_IFADDR_STATE_DAD;
3864 	} else if (ifp->state == INET6_IFADDR_STATE_ERRDAD) {
3865 		action = DAD_ABORT;
3866 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
3867 
3868 		if (idev->cnf.accept_dad > 1 && !idev->cnf.disable_ipv6 &&
3869 		    !(ifp->flags & IFA_F_STABLE_PRIVACY)) {
3870 			struct in6_addr addr;
3871 
3872 			addr.s6_addr32[0] = htonl(0xfe800000);
3873 			addr.s6_addr32[1] = 0;
3874 
3875 			if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
3876 			    ipv6_addr_equal(&ifp->addr, &addr)) {
3877 				/* DAD failed for link-local based on MAC */
3878 				idev->cnf.disable_ipv6 = 1;
3879 
3880 				pr_info("%s: IPv6 being disabled!\n",
3881 					ifp->idev->dev->name);
3882 				disable_ipv6 = true;
3883 			}
3884 		}
3885 	}
3886 	spin_unlock_bh(&ifp->lock);
3887 
3888 	if (action == DAD_BEGIN) {
3889 		addrconf_dad_begin(ifp);
3890 		goto out;
3891 	} else if (action == DAD_ABORT) {
3892 		in6_ifa_hold(ifp);
3893 		addrconf_dad_stop(ifp, 1);
3894 		if (disable_ipv6)
3895 			addrconf_ifdown(idev->dev, 0);
3896 		goto out;
3897 	}
3898 
3899 	if (!ifp->dad_probes && addrconf_dad_end(ifp))
3900 		goto out;
3901 
3902 	write_lock_bh(&idev->lock);
3903 	if (idev->dead || !(idev->if_flags & IF_READY)) {
3904 		write_unlock_bh(&idev->lock);
3905 		goto out;
3906 	}
3907 
3908 	spin_lock(&ifp->lock);
3909 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
3910 		spin_unlock(&ifp->lock);
3911 		write_unlock_bh(&idev->lock);
3912 		goto out;
3913 	}
3914 
3915 	if (ifp->dad_probes == 0) {
3916 		/*
3917 		 * DAD was successful
3918 		 */
3919 
3920 		bump_id = ifp->flags & IFA_F_TENTATIVE;
3921 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3922 		spin_unlock(&ifp->lock);
3923 		write_unlock_bh(&idev->lock);
3924 
3925 		addrconf_dad_completed(ifp, bump_id);
3926 
3927 		goto out;
3928 	}
3929 
3930 	ifp->dad_probes--;
3931 	addrconf_mod_dad_work(ifp,
3932 			      NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME));
3933 	spin_unlock(&ifp->lock);
3934 	write_unlock_bh(&idev->lock);
3935 
3936 	/* send a neighbour solicitation for our addr */
3937 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
3938 	ndisc_send_ns(ifp->idev->dev, &ifp->addr, &mcaddr, &in6addr_any,
3939 		      ifp->dad_nonce);
3940 out:
3941 	in6_ifa_put(ifp);
3942 	rtnl_unlock();
3943 }
3944 
3945 /* ifp->idev must be at least read locked */
3946 static bool ipv6_lonely_lladdr(struct inet6_ifaddr *ifp)
3947 {
3948 	struct inet6_ifaddr *ifpiter;
3949 	struct inet6_dev *idev = ifp->idev;
3950 
3951 	list_for_each_entry_reverse(ifpiter, &idev->addr_list, if_list) {
3952 		if (ifpiter->scope > IFA_LINK)
3953 			break;
3954 		if (ifp != ifpiter && ifpiter->scope == IFA_LINK &&
3955 		    (ifpiter->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE|
3956 				       IFA_F_OPTIMISTIC|IFA_F_DADFAILED)) ==
3957 		    IFA_F_PERMANENT)
3958 			return false;
3959 	}
3960 	return true;
3961 }
3962 
3963 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id)
3964 {
3965 	struct net_device *dev = ifp->idev->dev;
3966 	struct in6_addr lladdr;
3967 	bool send_rs, send_mld;
3968 
3969 	addrconf_del_dad_work(ifp);
3970 
3971 	/*
3972 	 *	Configure the address for reception. Now it is valid.
3973 	 */
3974 
3975 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
3976 
3977 	/* If added prefix is link local and we are prepared to process
3978 	   router advertisements, start sending router solicitations.
3979 	 */
3980 
3981 	read_lock_bh(&ifp->idev->lock);
3982 	send_mld = ifp->scope == IFA_LINK && ipv6_lonely_lladdr(ifp);
3983 	send_rs = send_mld &&
3984 		  ipv6_accept_ra(ifp->idev) &&
3985 		  ifp->idev->cnf.rtr_solicits != 0 &&
3986 		  (dev->flags&IFF_LOOPBACK) == 0;
3987 	read_unlock_bh(&ifp->idev->lock);
3988 
3989 	/* While dad is in progress mld report's source address is in6_addrany.
3990 	 * Resend with proper ll now.
3991 	 */
3992 	if (send_mld)
3993 		ipv6_mc_dad_complete(ifp->idev);
3994 
3995 	if (send_rs) {
3996 		/*
3997 		 *	If a host as already performed a random delay
3998 		 *	[...] as part of DAD [...] there is no need
3999 		 *	to delay again before sending the first RS
4000 		 */
4001 		if (ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4002 			return;
4003 		ndisc_send_rs(dev, &lladdr, &in6addr_linklocal_allrouters);
4004 
4005 		write_lock_bh(&ifp->idev->lock);
4006 		spin_lock(&ifp->lock);
4007 		ifp->idev->rs_interval = rfc3315_s14_backoff_init(
4008 			ifp->idev->cnf.rtr_solicit_interval);
4009 		ifp->idev->rs_probes = 1;
4010 		ifp->idev->if_flags |= IF_RS_SENT;
4011 		addrconf_mod_rs_timer(ifp->idev, ifp->idev->rs_interval);
4012 		spin_unlock(&ifp->lock);
4013 		write_unlock_bh(&ifp->idev->lock);
4014 	}
4015 
4016 	if (bump_id)
4017 		rt_genid_bump_ipv6(dev_net(dev));
4018 
4019 	/* Make sure that a new temporary address will be created
4020 	 * before this temporary address becomes deprecated.
4021 	 */
4022 	if (ifp->flags & IFA_F_TEMPORARY)
4023 		addrconf_verify_rtnl();
4024 }
4025 
4026 static void addrconf_dad_run(struct inet6_dev *idev)
4027 {
4028 	struct inet6_ifaddr *ifp;
4029 
4030 	read_lock_bh(&idev->lock);
4031 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
4032 		spin_lock(&ifp->lock);
4033 		if (ifp->flags & IFA_F_TENTATIVE &&
4034 		    ifp->state == INET6_IFADDR_STATE_DAD)
4035 			addrconf_dad_kick(ifp);
4036 		spin_unlock(&ifp->lock);
4037 	}
4038 	read_unlock_bh(&idev->lock);
4039 }
4040 
4041 #ifdef CONFIG_PROC_FS
4042 struct if6_iter_state {
4043 	struct seq_net_private p;
4044 	int bucket;
4045 	int offset;
4046 };
4047 
4048 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
4049 {
4050 	struct inet6_ifaddr *ifa = NULL;
4051 	struct if6_iter_state *state = seq->private;
4052 	struct net *net = seq_file_net(seq);
4053 	int p = 0;
4054 
4055 	/* initial bucket if pos is 0 */
4056 	if (pos == 0) {
4057 		state->bucket = 0;
4058 		state->offset = 0;
4059 	}
4060 
4061 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
4062 		hlist_for_each_entry_rcu_bh(ifa, &inet6_addr_lst[state->bucket],
4063 					 addr_lst) {
4064 			if (!net_eq(dev_net(ifa->idev->dev), net))
4065 				continue;
4066 			/* sync with offset */
4067 			if (p < state->offset) {
4068 				p++;
4069 				continue;
4070 			}
4071 			state->offset++;
4072 			return ifa;
4073 		}
4074 
4075 		/* prepare for next bucket */
4076 		state->offset = 0;
4077 		p = 0;
4078 	}
4079 	return NULL;
4080 }
4081 
4082 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
4083 					 struct inet6_ifaddr *ifa)
4084 {
4085 	struct if6_iter_state *state = seq->private;
4086 	struct net *net = seq_file_net(seq);
4087 
4088 	hlist_for_each_entry_continue_rcu_bh(ifa, addr_lst) {
4089 		if (!net_eq(dev_net(ifa->idev->dev), net))
4090 			continue;
4091 		state->offset++;
4092 		return ifa;
4093 	}
4094 
4095 	while (++state->bucket < IN6_ADDR_HSIZE) {
4096 		state->offset = 0;
4097 		hlist_for_each_entry_rcu_bh(ifa,
4098 				     &inet6_addr_lst[state->bucket], addr_lst) {
4099 			if (!net_eq(dev_net(ifa->idev->dev), net))
4100 				continue;
4101 			state->offset++;
4102 			return ifa;
4103 		}
4104 	}
4105 
4106 	return NULL;
4107 }
4108 
4109 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
4110 	__acquires(rcu_bh)
4111 {
4112 	rcu_read_lock_bh();
4113 	return if6_get_first(seq, *pos);
4114 }
4115 
4116 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4117 {
4118 	struct inet6_ifaddr *ifa;
4119 
4120 	ifa = if6_get_next(seq, v);
4121 	++*pos;
4122 	return ifa;
4123 }
4124 
4125 static void if6_seq_stop(struct seq_file *seq, void *v)
4126 	__releases(rcu_bh)
4127 {
4128 	rcu_read_unlock_bh();
4129 }
4130 
4131 static int if6_seq_show(struct seq_file *seq, void *v)
4132 {
4133 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
4134 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
4135 		   &ifp->addr,
4136 		   ifp->idev->dev->ifindex,
4137 		   ifp->prefix_len,
4138 		   ifp->scope,
4139 		   (u8) ifp->flags,
4140 		   ifp->idev->dev->name);
4141 	return 0;
4142 }
4143 
4144 static const struct seq_operations if6_seq_ops = {
4145 	.start	= if6_seq_start,
4146 	.next	= if6_seq_next,
4147 	.show	= if6_seq_show,
4148 	.stop	= if6_seq_stop,
4149 };
4150 
4151 static int if6_seq_open(struct inode *inode, struct file *file)
4152 {
4153 	return seq_open_net(inode, file, &if6_seq_ops,
4154 			    sizeof(struct if6_iter_state));
4155 }
4156 
4157 static const struct file_operations if6_fops = {
4158 	.owner		= THIS_MODULE,
4159 	.open		= if6_seq_open,
4160 	.read		= seq_read,
4161 	.llseek		= seq_lseek,
4162 	.release	= seq_release_net,
4163 };
4164 
4165 static int __net_init if6_proc_net_init(struct net *net)
4166 {
4167 	if (!proc_create("if_inet6", S_IRUGO, net->proc_net, &if6_fops))
4168 		return -ENOMEM;
4169 	return 0;
4170 }
4171 
4172 static void __net_exit if6_proc_net_exit(struct net *net)
4173 {
4174 	remove_proc_entry("if_inet6", net->proc_net);
4175 }
4176 
4177 static struct pernet_operations if6_proc_net_ops = {
4178 	.init = if6_proc_net_init,
4179 	.exit = if6_proc_net_exit,
4180 };
4181 
4182 int __init if6_proc_init(void)
4183 {
4184 	return register_pernet_subsys(&if6_proc_net_ops);
4185 }
4186 
4187 void if6_proc_exit(void)
4188 {
4189 	unregister_pernet_subsys(&if6_proc_net_ops);
4190 }
4191 #endif	/* CONFIG_PROC_FS */
4192 
4193 #if IS_ENABLED(CONFIG_IPV6_MIP6)
4194 /* Check if address is a home address configured on any interface. */
4195 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
4196 {
4197 	int ret = 0;
4198 	struct inet6_ifaddr *ifp = NULL;
4199 	unsigned int hash = inet6_addr_hash(addr);
4200 
4201 	rcu_read_lock_bh();
4202 	hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[hash], addr_lst) {
4203 		if (!net_eq(dev_net(ifp->idev->dev), net))
4204 			continue;
4205 		if (ipv6_addr_equal(&ifp->addr, addr) &&
4206 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
4207 			ret = 1;
4208 			break;
4209 		}
4210 	}
4211 	rcu_read_unlock_bh();
4212 	return ret;
4213 }
4214 #endif
4215 
4216 /*
4217  *	Periodic address status verification
4218  */
4219 
4220 static void addrconf_verify_rtnl(void)
4221 {
4222 	unsigned long now, next, next_sec, next_sched;
4223 	struct inet6_ifaddr *ifp;
4224 	int i;
4225 
4226 	ASSERT_RTNL();
4227 
4228 	rcu_read_lock_bh();
4229 	now = jiffies;
4230 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
4231 
4232 	cancel_delayed_work(&addr_chk_work);
4233 
4234 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
4235 restart:
4236 		hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[i], addr_lst) {
4237 			unsigned long age;
4238 
4239 			/* When setting preferred_lft to a value not zero or
4240 			 * infinity, while valid_lft is infinity
4241 			 * IFA_F_PERMANENT has a non-infinity life time.
4242 			 */
4243 			if ((ifp->flags & IFA_F_PERMANENT) &&
4244 			    (ifp->prefered_lft == INFINITY_LIFE_TIME))
4245 				continue;
4246 
4247 			spin_lock(&ifp->lock);
4248 			/* We try to batch several events at once. */
4249 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
4250 
4251 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
4252 			    age >= ifp->valid_lft) {
4253 				spin_unlock(&ifp->lock);
4254 				in6_ifa_hold(ifp);
4255 				ipv6_del_addr(ifp);
4256 				goto restart;
4257 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
4258 				spin_unlock(&ifp->lock);
4259 				continue;
4260 			} else if (age >= ifp->prefered_lft) {
4261 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
4262 				int deprecate = 0;
4263 
4264 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
4265 					deprecate = 1;
4266 					ifp->flags |= IFA_F_DEPRECATED;
4267 				}
4268 
4269 				if ((ifp->valid_lft != INFINITY_LIFE_TIME) &&
4270 				    (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)))
4271 					next = ifp->tstamp + ifp->valid_lft * HZ;
4272 
4273 				spin_unlock(&ifp->lock);
4274 
4275 				if (deprecate) {
4276 					in6_ifa_hold(ifp);
4277 
4278 					ipv6_ifa_notify(0, ifp);
4279 					in6_ifa_put(ifp);
4280 					goto restart;
4281 				}
4282 			} else if ((ifp->flags&IFA_F_TEMPORARY) &&
4283 				   !(ifp->flags&IFA_F_TENTATIVE)) {
4284 				unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
4285 					ifp->idev->cnf.dad_transmits *
4286 					NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME) / HZ;
4287 
4288 				if (age >= ifp->prefered_lft - regen_advance) {
4289 					struct inet6_ifaddr *ifpub = ifp->ifpub;
4290 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4291 						next = ifp->tstamp + ifp->prefered_lft * HZ;
4292 					if (!ifp->regen_count && ifpub) {
4293 						ifp->regen_count++;
4294 						in6_ifa_hold(ifp);
4295 						in6_ifa_hold(ifpub);
4296 						spin_unlock(&ifp->lock);
4297 
4298 						spin_lock(&ifpub->lock);
4299 						ifpub->regen_count = 0;
4300 						spin_unlock(&ifpub->lock);
4301 						ipv6_create_tempaddr(ifpub, ifp);
4302 						in6_ifa_put(ifpub);
4303 						in6_ifa_put(ifp);
4304 						goto restart;
4305 					}
4306 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
4307 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
4308 				spin_unlock(&ifp->lock);
4309 			} else {
4310 				/* ifp->prefered_lft <= ifp->valid_lft */
4311 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4312 					next = ifp->tstamp + ifp->prefered_lft * HZ;
4313 				spin_unlock(&ifp->lock);
4314 			}
4315 		}
4316 	}
4317 
4318 	next_sec = round_jiffies_up(next);
4319 	next_sched = next;
4320 
4321 	/* If rounded timeout is accurate enough, accept it. */
4322 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
4323 		next_sched = next_sec;
4324 
4325 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
4326 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
4327 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
4328 
4329 	ADBG(KERN_DEBUG "now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
4330 	      now, next, next_sec, next_sched);
4331 	mod_delayed_work(addrconf_wq, &addr_chk_work, next_sched - now);
4332 	rcu_read_unlock_bh();
4333 }
4334 
4335 static void addrconf_verify_work(struct work_struct *w)
4336 {
4337 	rtnl_lock();
4338 	addrconf_verify_rtnl();
4339 	rtnl_unlock();
4340 }
4341 
4342 static void addrconf_verify(void)
4343 {
4344 	mod_delayed_work(addrconf_wq, &addr_chk_work, 0);
4345 }
4346 
4347 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
4348 				     struct in6_addr **peer_pfx)
4349 {
4350 	struct in6_addr *pfx = NULL;
4351 
4352 	*peer_pfx = NULL;
4353 
4354 	if (addr)
4355 		pfx = nla_data(addr);
4356 
4357 	if (local) {
4358 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
4359 			*peer_pfx = pfx;
4360 		pfx = nla_data(local);
4361 	}
4362 
4363 	return pfx;
4364 }
4365 
4366 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
4367 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
4368 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
4369 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
4370 	[IFA_FLAGS]		= { .len = sizeof(u32) },
4371 };
4372 
4373 static int
4374 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh)
4375 {
4376 	struct net *net = sock_net(skb->sk);
4377 	struct ifaddrmsg *ifm;
4378 	struct nlattr *tb[IFA_MAX+1];
4379 	struct in6_addr *pfx, *peer_pfx;
4380 	u32 ifa_flags;
4381 	int err;
4382 
4383 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
4384 	if (err < 0)
4385 		return err;
4386 
4387 	ifm = nlmsg_data(nlh);
4388 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4389 	if (!pfx)
4390 		return -EINVAL;
4391 
4392 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
4393 
4394 	/* We ignore other flags so far. */
4395 	ifa_flags &= IFA_F_MANAGETEMPADDR;
4396 
4397 	return inet6_addr_del(net, ifm->ifa_index, ifa_flags, pfx,
4398 			      ifm->ifa_prefixlen);
4399 }
4400 
4401 static int inet6_addr_modify(struct inet6_ifaddr *ifp, u32 ifa_flags,
4402 			     u32 prefered_lft, u32 valid_lft)
4403 {
4404 	u32 flags;
4405 	clock_t expires;
4406 	unsigned long timeout;
4407 	bool was_managetempaddr;
4408 	bool had_prefixroute;
4409 
4410 	ASSERT_RTNL();
4411 
4412 	if (!valid_lft || (prefered_lft > valid_lft))
4413 		return -EINVAL;
4414 
4415 	if (ifa_flags & IFA_F_MANAGETEMPADDR &&
4416 	    (ifp->flags & IFA_F_TEMPORARY || ifp->prefix_len != 64))
4417 		return -EINVAL;
4418 
4419 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
4420 	if (addrconf_finite_timeout(timeout)) {
4421 		expires = jiffies_to_clock_t(timeout * HZ);
4422 		valid_lft = timeout;
4423 		flags = RTF_EXPIRES;
4424 	} else {
4425 		expires = 0;
4426 		flags = 0;
4427 		ifa_flags |= IFA_F_PERMANENT;
4428 	}
4429 
4430 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
4431 	if (addrconf_finite_timeout(timeout)) {
4432 		if (timeout == 0)
4433 			ifa_flags |= IFA_F_DEPRECATED;
4434 		prefered_lft = timeout;
4435 	}
4436 
4437 	spin_lock_bh(&ifp->lock);
4438 	was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;
4439 	had_prefixroute = ifp->flags & IFA_F_PERMANENT &&
4440 			  !(ifp->flags & IFA_F_NOPREFIXROUTE);
4441 	ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |
4442 			IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4443 			IFA_F_NOPREFIXROUTE);
4444 	ifp->flags |= ifa_flags;
4445 	ifp->tstamp = jiffies;
4446 	ifp->valid_lft = valid_lft;
4447 	ifp->prefered_lft = prefered_lft;
4448 
4449 	spin_unlock_bh(&ifp->lock);
4450 	if (!(ifp->flags&IFA_F_TENTATIVE))
4451 		ipv6_ifa_notify(0, ifp);
4452 
4453 	if (!(ifa_flags & IFA_F_NOPREFIXROUTE)) {
4454 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, ifp->idev->dev,
4455 				      expires, flags);
4456 	} else if (had_prefixroute) {
4457 		enum cleanup_prefix_rt_t action;
4458 		unsigned long rt_expires;
4459 
4460 		write_lock_bh(&ifp->idev->lock);
4461 		action = check_cleanup_prefix_route(ifp, &rt_expires);
4462 		write_unlock_bh(&ifp->idev->lock);
4463 
4464 		if (action != CLEANUP_PREFIX_RT_NOP) {
4465 			cleanup_prefix_route(ifp, rt_expires,
4466 				action == CLEANUP_PREFIX_RT_DEL);
4467 		}
4468 	}
4469 
4470 	if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {
4471 		if (was_managetempaddr && !(ifp->flags & IFA_F_MANAGETEMPADDR))
4472 			valid_lft = prefered_lft = 0;
4473 		manage_tempaddrs(ifp->idev, ifp, valid_lft, prefered_lft,
4474 				 !was_managetempaddr, jiffies);
4475 	}
4476 
4477 	addrconf_verify_rtnl();
4478 
4479 	return 0;
4480 }
4481 
4482 static int
4483 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh)
4484 {
4485 	struct net *net = sock_net(skb->sk);
4486 	struct ifaddrmsg *ifm;
4487 	struct nlattr *tb[IFA_MAX+1];
4488 	struct in6_addr *pfx, *peer_pfx;
4489 	struct inet6_ifaddr *ifa;
4490 	struct net_device *dev;
4491 	u32 valid_lft = INFINITY_LIFE_TIME, preferred_lft = INFINITY_LIFE_TIME;
4492 	u32 ifa_flags;
4493 	int err;
4494 
4495 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
4496 	if (err < 0)
4497 		return err;
4498 
4499 	ifm = nlmsg_data(nlh);
4500 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4501 	if (!pfx)
4502 		return -EINVAL;
4503 
4504 	if (tb[IFA_CACHEINFO]) {
4505 		struct ifa_cacheinfo *ci;
4506 
4507 		ci = nla_data(tb[IFA_CACHEINFO]);
4508 		valid_lft = ci->ifa_valid;
4509 		preferred_lft = ci->ifa_prefered;
4510 	} else {
4511 		preferred_lft = INFINITY_LIFE_TIME;
4512 		valid_lft = INFINITY_LIFE_TIME;
4513 	}
4514 
4515 	dev =  __dev_get_by_index(net, ifm->ifa_index);
4516 	if (!dev)
4517 		return -ENODEV;
4518 
4519 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
4520 
4521 	/* We ignore other flags so far. */
4522 	ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4523 		     IFA_F_NOPREFIXROUTE | IFA_F_MCAUTOJOIN;
4524 
4525 	ifa = ipv6_get_ifaddr(net, pfx, dev, 1);
4526 	if (!ifa) {
4527 		/*
4528 		 * It would be best to check for !NLM_F_CREATE here but
4529 		 * userspace already relies on not having to provide this.
4530 		 */
4531 		return inet6_addr_add(net, ifm->ifa_index, pfx, peer_pfx,
4532 				      ifm->ifa_prefixlen, ifa_flags,
4533 				      preferred_lft, valid_lft);
4534 	}
4535 
4536 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
4537 	    !(nlh->nlmsg_flags & NLM_F_REPLACE))
4538 		err = -EEXIST;
4539 	else
4540 		err = inet6_addr_modify(ifa, ifa_flags, preferred_lft, valid_lft);
4541 
4542 	in6_ifa_put(ifa);
4543 
4544 	return err;
4545 }
4546 
4547 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u32 flags,
4548 			  u8 scope, int ifindex)
4549 {
4550 	struct ifaddrmsg *ifm;
4551 
4552 	ifm = nlmsg_data(nlh);
4553 	ifm->ifa_family = AF_INET6;
4554 	ifm->ifa_prefixlen = prefixlen;
4555 	ifm->ifa_flags = flags;
4556 	ifm->ifa_scope = scope;
4557 	ifm->ifa_index = ifindex;
4558 }
4559 
4560 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
4561 			 unsigned long tstamp, u32 preferred, u32 valid)
4562 {
4563 	struct ifa_cacheinfo ci;
4564 
4565 	ci.cstamp = cstamp_delta(cstamp);
4566 	ci.tstamp = cstamp_delta(tstamp);
4567 	ci.ifa_prefered = preferred;
4568 	ci.ifa_valid = valid;
4569 
4570 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
4571 }
4572 
4573 static inline int rt_scope(int ifa_scope)
4574 {
4575 	if (ifa_scope & IFA_HOST)
4576 		return RT_SCOPE_HOST;
4577 	else if (ifa_scope & IFA_LINK)
4578 		return RT_SCOPE_LINK;
4579 	else if (ifa_scope & IFA_SITE)
4580 		return RT_SCOPE_SITE;
4581 	else
4582 		return RT_SCOPE_UNIVERSE;
4583 }
4584 
4585 static inline int inet6_ifaddr_msgsize(void)
4586 {
4587 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
4588 	       + nla_total_size(16) /* IFA_LOCAL */
4589 	       + nla_total_size(16) /* IFA_ADDRESS */
4590 	       + nla_total_size(sizeof(struct ifa_cacheinfo))
4591 	       + nla_total_size(4)  /* IFA_FLAGS */;
4592 }
4593 
4594 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
4595 			     u32 portid, u32 seq, int event, unsigned int flags)
4596 {
4597 	struct nlmsghdr  *nlh;
4598 	u32 preferred, valid;
4599 
4600 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4601 	if (!nlh)
4602 		return -EMSGSIZE;
4603 
4604 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
4605 		      ifa->idev->dev->ifindex);
4606 
4607 	if (!((ifa->flags&IFA_F_PERMANENT) &&
4608 	      (ifa->prefered_lft == INFINITY_LIFE_TIME))) {
4609 		preferred = ifa->prefered_lft;
4610 		valid = ifa->valid_lft;
4611 		if (preferred != INFINITY_LIFE_TIME) {
4612 			long tval = (jiffies - ifa->tstamp)/HZ;
4613 			if (preferred > tval)
4614 				preferred -= tval;
4615 			else
4616 				preferred = 0;
4617 			if (valid != INFINITY_LIFE_TIME) {
4618 				if (valid > tval)
4619 					valid -= tval;
4620 				else
4621 					valid = 0;
4622 			}
4623 		}
4624 	} else {
4625 		preferred = INFINITY_LIFE_TIME;
4626 		valid = INFINITY_LIFE_TIME;
4627 	}
4628 
4629 	if (!ipv6_addr_any(&ifa->peer_addr)) {
4630 		if (nla_put_in6_addr(skb, IFA_LOCAL, &ifa->addr) < 0 ||
4631 		    nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->peer_addr) < 0)
4632 			goto error;
4633 	} else
4634 		if (nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->addr) < 0)
4635 			goto error;
4636 
4637 	if (put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0)
4638 		goto error;
4639 
4640 	if (nla_put_u32(skb, IFA_FLAGS, ifa->flags) < 0)
4641 		goto error;
4642 
4643 	nlmsg_end(skb, nlh);
4644 	return 0;
4645 
4646 error:
4647 	nlmsg_cancel(skb, nlh);
4648 	return -EMSGSIZE;
4649 }
4650 
4651 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
4652 				u32 portid, u32 seq, int event, u16 flags)
4653 {
4654 	struct nlmsghdr  *nlh;
4655 	u8 scope = RT_SCOPE_UNIVERSE;
4656 	int ifindex = ifmca->idev->dev->ifindex;
4657 
4658 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
4659 		scope = RT_SCOPE_SITE;
4660 
4661 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4662 	if (!nlh)
4663 		return -EMSGSIZE;
4664 
4665 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4666 	if (nla_put_in6_addr(skb, IFA_MULTICAST, &ifmca->mca_addr) < 0 ||
4667 	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
4668 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4669 		nlmsg_cancel(skb, nlh);
4670 		return -EMSGSIZE;
4671 	}
4672 
4673 	nlmsg_end(skb, nlh);
4674 	return 0;
4675 }
4676 
4677 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
4678 				u32 portid, u32 seq, int event, unsigned int flags)
4679 {
4680 	struct nlmsghdr  *nlh;
4681 	u8 scope = RT_SCOPE_UNIVERSE;
4682 	int ifindex = ifaca->aca_idev->dev->ifindex;
4683 
4684 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
4685 		scope = RT_SCOPE_SITE;
4686 
4687 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4688 	if (!nlh)
4689 		return -EMSGSIZE;
4690 
4691 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4692 	if (nla_put_in6_addr(skb, IFA_ANYCAST, &ifaca->aca_addr) < 0 ||
4693 	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
4694 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4695 		nlmsg_cancel(skb, nlh);
4696 		return -EMSGSIZE;
4697 	}
4698 
4699 	nlmsg_end(skb, nlh);
4700 	return 0;
4701 }
4702 
4703 enum addr_type_t {
4704 	UNICAST_ADDR,
4705 	MULTICAST_ADDR,
4706 	ANYCAST_ADDR,
4707 };
4708 
4709 /* called with rcu_read_lock() */
4710 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
4711 			  struct netlink_callback *cb, enum addr_type_t type,
4712 			  int s_ip_idx, int *p_ip_idx)
4713 {
4714 	struct ifmcaddr6 *ifmca;
4715 	struct ifacaddr6 *ifaca;
4716 	int err = 1;
4717 	int ip_idx = *p_ip_idx;
4718 
4719 	read_lock_bh(&idev->lock);
4720 	switch (type) {
4721 	case UNICAST_ADDR: {
4722 		struct inet6_ifaddr *ifa;
4723 
4724 		/* unicast address incl. temp addr */
4725 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
4726 			if (++ip_idx < s_ip_idx)
4727 				continue;
4728 			err = inet6_fill_ifaddr(skb, ifa,
4729 						NETLINK_CB(cb->skb).portid,
4730 						cb->nlh->nlmsg_seq,
4731 						RTM_NEWADDR,
4732 						NLM_F_MULTI);
4733 			if (err < 0)
4734 				break;
4735 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
4736 		}
4737 		break;
4738 	}
4739 	case MULTICAST_ADDR:
4740 		/* multicast address */
4741 		for (ifmca = idev->mc_list; ifmca;
4742 		     ifmca = ifmca->next, ip_idx++) {
4743 			if (ip_idx < s_ip_idx)
4744 				continue;
4745 			err = inet6_fill_ifmcaddr(skb, ifmca,
4746 						  NETLINK_CB(cb->skb).portid,
4747 						  cb->nlh->nlmsg_seq,
4748 						  RTM_GETMULTICAST,
4749 						  NLM_F_MULTI);
4750 			if (err < 0)
4751 				break;
4752 		}
4753 		break;
4754 	case ANYCAST_ADDR:
4755 		/* anycast address */
4756 		for (ifaca = idev->ac_list; ifaca;
4757 		     ifaca = ifaca->aca_next, ip_idx++) {
4758 			if (ip_idx < s_ip_idx)
4759 				continue;
4760 			err = inet6_fill_ifacaddr(skb, ifaca,
4761 						  NETLINK_CB(cb->skb).portid,
4762 						  cb->nlh->nlmsg_seq,
4763 						  RTM_GETANYCAST,
4764 						  NLM_F_MULTI);
4765 			if (err < 0)
4766 				break;
4767 		}
4768 		break;
4769 	default:
4770 		break;
4771 	}
4772 	read_unlock_bh(&idev->lock);
4773 	*p_ip_idx = ip_idx;
4774 	return err;
4775 }
4776 
4777 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
4778 			   enum addr_type_t type)
4779 {
4780 	struct net *net = sock_net(skb->sk);
4781 	int h, s_h;
4782 	int idx, ip_idx;
4783 	int s_idx, s_ip_idx;
4784 	struct net_device *dev;
4785 	struct inet6_dev *idev;
4786 	struct hlist_head *head;
4787 
4788 	s_h = cb->args[0];
4789 	s_idx = idx = cb->args[1];
4790 	s_ip_idx = ip_idx = cb->args[2];
4791 
4792 	rcu_read_lock();
4793 	cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^ net->dev_base_seq;
4794 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
4795 		idx = 0;
4796 		head = &net->dev_index_head[h];
4797 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
4798 			if (idx < s_idx)
4799 				goto cont;
4800 			if (h > s_h || idx > s_idx)
4801 				s_ip_idx = 0;
4802 			ip_idx = 0;
4803 			idev = __in6_dev_get(dev);
4804 			if (!idev)
4805 				goto cont;
4806 
4807 			if (in6_dump_addrs(idev, skb, cb, type,
4808 					   s_ip_idx, &ip_idx) < 0)
4809 				goto done;
4810 cont:
4811 			idx++;
4812 		}
4813 	}
4814 done:
4815 	rcu_read_unlock();
4816 	cb->args[0] = h;
4817 	cb->args[1] = idx;
4818 	cb->args[2] = ip_idx;
4819 
4820 	return skb->len;
4821 }
4822 
4823 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
4824 {
4825 	enum addr_type_t type = UNICAST_ADDR;
4826 
4827 	return inet6_dump_addr(skb, cb, type);
4828 }
4829 
4830 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
4831 {
4832 	enum addr_type_t type = MULTICAST_ADDR;
4833 
4834 	return inet6_dump_addr(skb, cb, type);
4835 }
4836 
4837 
4838 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
4839 {
4840 	enum addr_type_t type = ANYCAST_ADDR;
4841 
4842 	return inet6_dump_addr(skb, cb, type);
4843 }
4844 
4845 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh)
4846 {
4847 	struct net *net = sock_net(in_skb->sk);
4848 	struct ifaddrmsg *ifm;
4849 	struct nlattr *tb[IFA_MAX+1];
4850 	struct in6_addr *addr = NULL, *peer;
4851 	struct net_device *dev = NULL;
4852 	struct inet6_ifaddr *ifa;
4853 	struct sk_buff *skb;
4854 	int err;
4855 
4856 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
4857 	if (err < 0)
4858 		goto errout;
4859 
4860 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
4861 	if (!addr) {
4862 		err = -EINVAL;
4863 		goto errout;
4864 	}
4865 
4866 	ifm = nlmsg_data(nlh);
4867 	if (ifm->ifa_index)
4868 		dev = __dev_get_by_index(net, ifm->ifa_index);
4869 
4870 	ifa = ipv6_get_ifaddr(net, addr, dev, 1);
4871 	if (!ifa) {
4872 		err = -EADDRNOTAVAIL;
4873 		goto errout;
4874 	}
4875 
4876 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
4877 	if (!skb) {
4878 		err = -ENOBUFS;
4879 		goto errout_ifa;
4880 	}
4881 
4882 	err = inet6_fill_ifaddr(skb, ifa, NETLINK_CB(in_skb).portid,
4883 				nlh->nlmsg_seq, RTM_NEWADDR, 0);
4884 	if (err < 0) {
4885 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
4886 		WARN_ON(err == -EMSGSIZE);
4887 		kfree_skb(skb);
4888 		goto errout_ifa;
4889 	}
4890 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
4891 errout_ifa:
4892 	in6_ifa_put(ifa);
4893 errout:
4894 	return err;
4895 }
4896 
4897 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
4898 {
4899 	struct sk_buff *skb;
4900 	struct net *net = dev_net(ifa->idev->dev);
4901 	int err = -ENOBUFS;
4902 
4903 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
4904 	if (!skb)
4905 		goto errout;
4906 
4907 	err = inet6_fill_ifaddr(skb, ifa, 0, 0, event, 0);
4908 	if (err < 0) {
4909 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
4910 		WARN_ON(err == -EMSGSIZE);
4911 		kfree_skb(skb);
4912 		goto errout;
4913 	}
4914 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
4915 	return;
4916 errout:
4917 	if (err < 0)
4918 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
4919 }
4920 
4921 static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
4922 				__s32 *array, int bytes)
4923 {
4924 	BUG_ON(bytes < (DEVCONF_MAX * 4));
4925 
4926 	memset(array, 0, bytes);
4927 	array[DEVCONF_FORWARDING] = cnf->forwarding;
4928 	array[DEVCONF_HOPLIMIT] = cnf->hop_limit;
4929 	array[DEVCONF_MTU6] = cnf->mtu6;
4930 	array[DEVCONF_ACCEPT_RA] = cnf->accept_ra;
4931 	array[DEVCONF_ACCEPT_REDIRECTS] = cnf->accept_redirects;
4932 	array[DEVCONF_AUTOCONF] = cnf->autoconf;
4933 	array[DEVCONF_DAD_TRANSMITS] = cnf->dad_transmits;
4934 	array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
4935 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
4936 		jiffies_to_msecs(cnf->rtr_solicit_interval);
4937 	array[DEVCONF_RTR_SOLICIT_MAX_INTERVAL] =
4938 		jiffies_to_msecs(cnf->rtr_solicit_max_interval);
4939 	array[DEVCONF_RTR_SOLICIT_DELAY] =
4940 		jiffies_to_msecs(cnf->rtr_solicit_delay);
4941 	array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;
4942 	array[DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL] =
4943 		jiffies_to_msecs(cnf->mldv1_unsolicited_report_interval);
4944 	array[DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL] =
4945 		jiffies_to_msecs(cnf->mldv2_unsolicited_report_interval);
4946 	array[DEVCONF_USE_TEMPADDR] = cnf->use_tempaddr;
4947 	array[DEVCONF_TEMP_VALID_LFT] = cnf->temp_valid_lft;
4948 	array[DEVCONF_TEMP_PREFERED_LFT] = cnf->temp_prefered_lft;
4949 	array[DEVCONF_REGEN_MAX_RETRY] = cnf->regen_max_retry;
4950 	array[DEVCONF_MAX_DESYNC_FACTOR] = cnf->max_desync_factor;
4951 	array[DEVCONF_MAX_ADDRESSES] = cnf->max_addresses;
4952 	array[DEVCONF_ACCEPT_RA_DEFRTR] = cnf->accept_ra_defrtr;
4953 	array[DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT] = cnf->accept_ra_min_hop_limit;
4954 	array[DEVCONF_ACCEPT_RA_PINFO] = cnf->accept_ra_pinfo;
4955 #ifdef CONFIG_IPV6_ROUTER_PREF
4956 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = cnf->accept_ra_rtr_pref;
4957 	array[DEVCONF_RTR_PROBE_INTERVAL] =
4958 		jiffies_to_msecs(cnf->rtr_probe_interval);
4959 #ifdef CONFIG_IPV6_ROUTE_INFO
4960 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
4961 #endif
4962 #endif
4963 	array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
4964 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
4965 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
4966 	array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
4967 	array[DEVCONF_USE_OPTIMISTIC] = cnf->use_optimistic;
4968 #endif
4969 #ifdef CONFIG_IPV6_MROUTE
4970 	array[DEVCONF_MC_FORWARDING] = cnf->mc_forwarding;
4971 #endif
4972 	array[DEVCONF_DISABLE_IPV6] = cnf->disable_ipv6;
4973 	array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad;
4974 	array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao;
4975 	array[DEVCONF_NDISC_NOTIFY] = cnf->ndisc_notify;
4976 	array[DEVCONF_SUPPRESS_FRAG_NDISC] = cnf->suppress_frag_ndisc;
4977 	array[DEVCONF_ACCEPT_RA_FROM_LOCAL] = cnf->accept_ra_from_local;
4978 	array[DEVCONF_ACCEPT_RA_MTU] = cnf->accept_ra_mtu;
4979 	array[DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN] = cnf->ignore_routes_with_linkdown;
4980 	/* we omit DEVCONF_STABLE_SECRET for now */
4981 	array[DEVCONF_USE_OIF_ADDRS_ONLY] = cnf->use_oif_addrs_only;
4982 	array[DEVCONF_DROP_UNICAST_IN_L2_MULTICAST] = cnf->drop_unicast_in_l2_multicast;
4983 	array[DEVCONF_DROP_UNSOLICITED_NA] = cnf->drop_unsolicited_na;
4984 	array[DEVCONF_KEEP_ADDR_ON_DOWN] = cnf->keep_addr_on_down;
4985 	array[DEVCONF_SEG6_ENABLED] = cnf->seg6_enabled;
4986 #ifdef CONFIG_IPV6_SEG6_HMAC
4987 	array[DEVCONF_SEG6_REQUIRE_HMAC] = cnf->seg6_require_hmac;
4988 #endif
4989 	array[DEVCONF_ENHANCED_DAD] = cnf->enhanced_dad;
4990 }
4991 
4992 static inline size_t inet6_ifla6_size(void)
4993 {
4994 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
4995 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
4996 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
4997 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
4998 	     + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
4999 	     + nla_total_size(sizeof(struct in6_addr)); /* IFLA_INET6_TOKEN */
5000 }
5001 
5002 static inline size_t inet6_if_nlmsg_size(void)
5003 {
5004 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
5005 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
5006 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
5007 	       + nla_total_size(4) /* IFLA_MTU */
5008 	       + nla_total_size(4) /* IFLA_LINK */
5009 	       + nla_total_size(1) /* IFLA_OPERSTATE */
5010 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
5011 }
5012 
5013 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
5014 					int bytes)
5015 {
5016 	int i;
5017 	int pad = bytes - sizeof(u64) * ICMP6_MIB_MAX;
5018 	BUG_ON(pad < 0);
5019 
5020 	/* Use put_unaligned() because stats may not be aligned for u64. */
5021 	put_unaligned(ICMP6_MIB_MAX, &stats[0]);
5022 	for (i = 1; i < ICMP6_MIB_MAX; i++)
5023 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
5024 
5025 	memset(&stats[ICMP6_MIB_MAX], 0, pad);
5026 }
5027 
5028 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu *mib,
5029 					int bytes, size_t syncpoff)
5030 {
5031 	int i, c;
5032 	u64 buff[IPSTATS_MIB_MAX];
5033 	int pad = bytes - sizeof(u64) * IPSTATS_MIB_MAX;
5034 
5035 	BUG_ON(pad < 0);
5036 
5037 	memset(buff, 0, sizeof(buff));
5038 	buff[0] = IPSTATS_MIB_MAX;
5039 
5040 	for_each_possible_cpu(c) {
5041 		for (i = 1; i < IPSTATS_MIB_MAX; i++)
5042 			buff[i] += snmp_get_cpu_field64(mib, c, i, syncpoff);
5043 	}
5044 
5045 	memcpy(stats, buff, IPSTATS_MIB_MAX * sizeof(u64));
5046 	memset(&stats[IPSTATS_MIB_MAX], 0, pad);
5047 }
5048 
5049 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
5050 			     int bytes)
5051 {
5052 	switch (attrtype) {
5053 	case IFLA_INET6_STATS:
5054 		__snmp6_fill_stats64(stats, idev->stats.ipv6, bytes,
5055 				     offsetof(struct ipstats_mib, syncp));
5056 		break;
5057 	case IFLA_INET6_ICMP6STATS:
5058 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, bytes);
5059 		break;
5060 	}
5061 }
5062 
5063 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev,
5064 				  u32 ext_filter_mask)
5065 {
5066 	struct nlattr *nla;
5067 	struct ifla_cacheinfo ci;
5068 
5069 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, idev->if_flags))
5070 		goto nla_put_failure;
5071 	ci.max_reasm_len = IPV6_MAXPLEN;
5072 	ci.tstamp = cstamp_delta(idev->tstamp);
5073 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
5074 	ci.retrans_time = jiffies_to_msecs(NEIGH_VAR(idev->nd_parms, RETRANS_TIME));
5075 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
5076 		goto nla_put_failure;
5077 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
5078 	if (!nla)
5079 		goto nla_put_failure;
5080 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
5081 
5082 	/* XXX - MC not implemented */
5083 
5084 	if (ext_filter_mask & RTEXT_FILTER_SKIP_STATS)
5085 		return 0;
5086 
5087 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
5088 	if (!nla)
5089 		goto nla_put_failure;
5090 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
5091 
5092 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
5093 	if (!nla)
5094 		goto nla_put_failure;
5095 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
5096 
5097 	nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
5098 	if (!nla)
5099 		goto nla_put_failure;
5100 
5101 	if (nla_put_u8(skb, IFLA_INET6_ADDR_GEN_MODE, idev->addr_gen_mode))
5102 		goto nla_put_failure;
5103 
5104 	read_lock_bh(&idev->lock);
5105 	memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
5106 	read_unlock_bh(&idev->lock);
5107 
5108 	return 0;
5109 
5110 nla_put_failure:
5111 	return -EMSGSIZE;
5112 }
5113 
5114 static size_t inet6_get_link_af_size(const struct net_device *dev,
5115 				     u32 ext_filter_mask)
5116 {
5117 	if (!__in6_dev_get(dev))
5118 		return 0;
5119 
5120 	return inet6_ifla6_size();
5121 }
5122 
5123 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev,
5124 			      u32 ext_filter_mask)
5125 {
5126 	struct inet6_dev *idev = __in6_dev_get(dev);
5127 
5128 	if (!idev)
5129 		return -ENODATA;
5130 
5131 	if (inet6_fill_ifla6_attrs(skb, idev, ext_filter_mask) < 0)
5132 		return -EMSGSIZE;
5133 
5134 	return 0;
5135 }
5136 
5137 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token)
5138 {
5139 	struct inet6_ifaddr *ifp;
5140 	struct net_device *dev = idev->dev;
5141 	bool clear_token, update_rs = false;
5142 	struct in6_addr ll_addr;
5143 
5144 	ASSERT_RTNL();
5145 
5146 	if (!token)
5147 		return -EINVAL;
5148 	if (dev->flags & (IFF_LOOPBACK | IFF_NOARP))
5149 		return -EINVAL;
5150 	if (!ipv6_accept_ra(idev))
5151 		return -EINVAL;
5152 	if (idev->cnf.rtr_solicits == 0)
5153 		return -EINVAL;
5154 
5155 	write_lock_bh(&idev->lock);
5156 
5157 	BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
5158 	memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
5159 
5160 	write_unlock_bh(&idev->lock);
5161 
5162 	clear_token = ipv6_addr_any(token);
5163 	if (clear_token)
5164 		goto update_lft;
5165 
5166 	if (!idev->dead && (idev->if_flags & IF_READY) &&
5167 	    !ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
5168 			     IFA_F_OPTIMISTIC)) {
5169 		/* If we're not ready, then normal ifup will take care
5170 		 * of this. Otherwise, we need to request our rs here.
5171 		 */
5172 		ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
5173 		update_rs = true;
5174 	}
5175 
5176 update_lft:
5177 	write_lock_bh(&idev->lock);
5178 
5179 	if (update_rs) {
5180 		idev->if_flags |= IF_RS_SENT;
5181 		idev->rs_interval = rfc3315_s14_backoff_init(
5182 			idev->cnf.rtr_solicit_interval);
5183 		idev->rs_probes = 1;
5184 		addrconf_mod_rs_timer(idev, idev->rs_interval);
5185 	}
5186 
5187 	/* Well, that's kinda nasty ... */
5188 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
5189 		spin_lock(&ifp->lock);
5190 		if (ifp->tokenized) {
5191 			ifp->valid_lft = 0;
5192 			ifp->prefered_lft = 0;
5193 		}
5194 		spin_unlock(&ifp->lock);
5195 	}
5196 
5197 	write_unlock_bh(&idev->lock);
5198 	inet6_ifinfo_notify(RTM_NEWLINK, idev);
5199 	addrconf_verify_rtnl();
5200 	return 0;
5201 }
5202 
5203 static const struct nla_policy inet6_af_policy[IFLA_INET6_MAX + 1] = {
5204 	[IFLA_INET6_ADDR_GEN_MODE]	= { .type = NLA_U8 },
5205 	[IFLA_INET6_TOKEN]		= { .len = sizeof(struct in6_addr) },
5206 };
5207 
5208 static int inet6_validate_link_af(const struct net_device *dev,
5209 				  const struct nlattr *nla)
5210 {
5211 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5212 
5213 	if (dev && !__in6_dev_get(dev))
5214 		return -EAFNOSUPPORT;
5215 
5216 	return nla_parse_nested(tb, IFLA_INET6_MAX, nla, inet6_af_policy);
5217 }
5218 
5219 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla)
5220 {
5221 	int err = -EINVAL;
5222 	struct inet6_dev *idev = __in6_dev_get(dev);
5223 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5224 
5225 	if (!idev)
5226 		return -EAFNOSUPPORT;
5227 
5228 	if (nla_parse_nested(tb, IFLA_INET6_MAX, nla, NULL) < 0)
5229 		BUG();
5230 
5231 	if (tb[IFLA_INET6_TOKEN]) {
5232 		err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]));
5233 		if (err)
5234 			return err;
5235 	}
5236 
5237 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
5238 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
5239 
5240 		if (mode != IN6_ADDR_GEN_MODE_EUI64 &&
5241 		    mode != IN6_ADDR_GEN_MODE_NONE &&
5242 		    mode != IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5243 		    mode != IN6_ADDR_GEN_MODE_RANDOM)
5244 			return -EINVAL;
5245 
5246 		if (mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5247 		    !idev->cnf.stable_secret.initialized &&
5248 		    !dev_net(dev)->ipv6.devconf_dflt->stable_secret.initialized)
5249 			return -EINVAL;
5250 
5251 		idev->addr_gen_mode = mode;
5252 		err = 0;
5253 	}
5254 
5255 	return err;
5256 }
5257 
5258 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
5259 			     u32 portid, u32 seq, int event, unsigned int flags)
5260 {
5261 	struct net_device *dev = idev->dev;
5262 	struct ifinfomsg *hdr;
5263 	struct nlmsghdr *nlh;
5264 	void *protoinfo;
5265 
5266 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
5267 	if (!nlh)
5268 		return -EMSGSIZE;
5269 
5270 	hdr = nlmsg_data(nlh);
5271 	hdr->ifi_family = AF_INET6;
5272 	hdr->__ifi_pad = 0;
5273 	hdr->ifi_type = dev->type;
5274 	hdr->ifi_index = dev->ifindex;
5275 	hdr->ifi_flags = dev_get_flags(dev);
5276 	hdr->ifi_change = 0;
5277 
5278 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
5279 	    (dev->addr_len &&
5280 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
5281 	    nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
5282 	    (dev->ifindex != dev_get_iflink(dev) &&
5283 	     nla_put_u32(skb, IFLA_LINK, dev_get_iflink(dev))) ||
5284 	    nla_put_u8(skb, IFLA_OPERSTATE,
5285 		       netif_running(dev) ? dev->operstate : IF_OPER_DOWN))
5286 		goto nla_put_failure;
5287 	protoinfo = nla_nest_start(skb, IFLA_PROTINFO);
5288 	if (!protoinfo)
5289 		goto nla_put_failure;
5290 
5291 	if (inet6_fill_ifla6_attrs(skb, idev, 0) < 0)
5292 		goto nla_put_failure;
5293 
5294 	nla_nest_end(skb, protoinfo);
5295 	nlmsg_end(skb, nlh);
5296 	return 0;
5297 
5298 nla_put_failure:
5299 	nlmsg_cancel(skb, nlh);
5300 	return -EMSGSIZE;
5301 }
5302 
5303 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
5304 {
5305 	struct net *net = sock_net(skb->sk);
5306 	int h, s_h;
5307 	int idx = 0, s_idx;
5308 	struct net_device *dev;
5309 	struct inet6_dev *idev;
5310 	struct hlist_head *head;
5311 
5312 	s_h = cb->args[0];
5313 	s_idx = cb->args[1];
5314 
5315 	rcu_read_lock();
5316 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
5317 		idx = 0;
5318 		head = &net->dev_index_head[h];
5319 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
5320 			if (idx < s_idx)
5321 				goto cont;
5322 			idev = __in6_dev_get(dev);
5323 			if (!idev)
5324 				goto cont;
5325 			if (inet6_fill_ifinfo(skb, idev,
5326 					      NETLINK_CB(cb->skb).portid,
5327 					      cb->nlh->nlmsg_seq,
5328 					      RTM_NEWLINK, NLM_F_MULTI) < 0)
5329 				goto out;
5330 cont:
5331 			idx++;
5332 		}
5333 	}
5334 out:
5335 	rcu_read_unlock();
5336 	cb->args[1] = idx;
5337 	cb->args[0] = h;
5338 
5339 	return skb->len;
5340 }
5341 
5342 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
5343 {
5344 	struct sk_buff *skb;
5345 	struct net *net = dev_net(idev->dev);
5346 	int err = -ENOBUFS;
5347 
5348 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
5349 	if (!skb)
5350 		goto errout;
5351 
5352 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
5353 	if (err < 0) {
5354 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
5355 		WARN_ON(err == -EMSGSIZE);
5356 		kfree_skb(skb);
5357 		goto errout;
5358 	}
5359 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
5360 	return;
5361 errout:
5362 	if (err < 0)
5363 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
5364 }
5365 
5366 static inline size_t inet6_prefix_nlmsg_size(void)
5367 {
5368 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
5369 	       + nla_total_size(sizeof(struct in6_addr))
5370 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
5371 }
5372 
5373 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
5374 			     struct prefix_info *pinfo, u32 portid, u32 seq,
5375 			     int event, unsigned int flags)
5376 {
5377 	struct prefixmsg *pmsg;
5378 	struct nlmsghdr *nlh;
5379 	struct prefix_cacheinfo	ci;
5380 
5381 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
5382 	if (!nlh)
5383 		return -EMSGSIZE;
5384 
5385 	pmsg = nlmsg_data(nlh);
5386 	pmsg->prefix_family = AF_INET6;
5387 	pmsg->prefix_pad1 = 0;
5388 	pmsg->prefix_pad2 = 0;
5389 	pmsg->prefix_ifindex = idev->dev->ifindex;
5390 	pmsg->prefix_len = pinfo->prefix_len;
5391 	pmsg->prefix_type = pinfo->type;
5392 	pmsg->prefix_pad3 = 0;
5393 	pmsg->prefix_flags = 0;
5394 	if (pinfo->onlink)
5395 		pmsg->prefix_flags |= IF_PREFIX_ONLINK;
5396 	if (pinfo->autoconf)
5397 		pmsg->prefix_flags |= IF_PREFIX_AUTOCONF;
5398 
5399 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
5400 		goto nla_put_failure;
5401 	ci.preferred_time = ntohl(pinfo->prefered);
5402 	ci.valid_time = ntohl(pinfo->valid);
5403 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
5404 		goto nla_put_failure;
5405 	nlmsg_end(skb, nlh);
5406 	return 0;
5407 
5408 nla_put_failure:
5409 	nlmsg_cancel(skb, nlh);
5410 	return -EMSGSIZE;
5411 }
5412 
5413 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
5414 			 struct prefix_info *pinfo)
5415 {
5416 	struct sk_buff *skb;
5417 	struct net *net = dev_net(idev->dev);
5418 	int err = -ENOBUFS;
5419 
5420 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
5421 	if (!skb)
5422 		goto errout;
5423 
5424 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
5425 	if (err < 0) {
5426 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
5427 		WARN_ON(err == -EMSGSIZE);
5428 		kfree_skb(skb);
5429 		goto errout;
5430 	}
5431 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
5432 	return;
5433 errout:
5434 	if (err < 0)
5435 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
5436 }
5437 
5438 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
5439 {
5440 	struct net *net = dev_net(ifp->idev->dev);
5441 
5442 	if (event)
5443 		ASSERT_RTNL();
5444 
5445 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
5446 
5447 	switch (event) {
5448 	case RTM_NEWADDR:
5449 		/*
5450 		 * If the address was optimistic
5451 		 * we inserted the route at the start of
5452 		 * our DAD process, so we don't need
5453 		 * to do it again
5454 		 */
5455 		if (!(ifp->rt->rt6i_node))
5456 			ip6_ins_rt(ifp->rt);
5457 		if (ifp->idev->cnf.forwarding)
5458 			addrconf_join_anycast(ifp);
5459 		if (!ipv6_addr_any(&ifp->peer_addr))
5460 			addrconf_prefix_route(&ifp->peer_addr, 128,
5461 					      ifp->idev->dev, 0, 0);
5462 		break;
5463 	case RTM_DELADDR:
5464 		if (ifp->idev->cnf.forwarding)
5465 			addrconf_leave_anycast(ifp);
5466 		addrconf_leave_solict(ifp->idev, &ifp->addr);
5467 		if (!ipv6_addr_any(&ifp->peer_addr)) {
5468 			struct rt6_info *rt;
5469 
5470 			rt = addrconf_get_prefix_route(&ifp->peer_addr, 128,
5471 						       ifp->idev->dev, 0, 0);
5472 			if (rt)
5473 				ip6_del_rt(rt);
5474 		}
5475 		if (ifp->rt) {
5476 			dst_hold(&ifp->rt->dst);
5477 			ip6_del_rt(ifp->rt);
5478 		}
5479 		rt_genid_bump_ipv6(net);
5480 		break;
5481 	}
5482 	atomic_inc(&net->ipv6.dev_addr_genid);
5483 }
5484 
5485 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
5486 {
5487 	rcu_read_lock_bh();
5488 	if (likely(ifp->idev->dead == 0))
5489 		__ipv6_ifa_notify(event, ifp);
5490 	rcu_read_unlock_bh();
5491 }
5492 
5493 #ifdef CONFIG_SYSCTL
5494 
5495 static
5496 int addrconf_sysctl_forward(struct ctl_table *ctl, int write,
5497 			   void __user *buffer, size_t *lenp, loff_t *ppos)
5498 {
5499 	int *valp = ctl->data;
5500 	int val = *valp;
5501 	loff_t pos = *ppos;
5502 	struct ctl_table lctl;
5503 	int ret;
5504 
5505 	/*
5506 	 * ctl->data points to idev->cnf.forwarding, we should
5507 	 * not modify it until we get the rtnl lock.
5508 	 */
5509 	lctl = *ctl;
5510 	lctl.data = &val;
5511 
5512 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5513 
5514 	if (write)
5515 		ret = addrconf_fixup_forwarding(ctl, valp, val);
5516 	if (ret)
5517 		*ppos = pos;
5518 	return ret;
5519 }
5520 
5521 static
5522 int addrconf_sysctl_mtu(struct ctl_table *ctl, int write,
5523 			void __user *buffer, size_t *lenp, loff_t *ppos)
5524 {
5525 	struct inet6_dev *idev = ctl->extra1;
5526 	int min_mtu = IPV6_MIN_MTU;
5527 	struct ctl_table lctl;
5528 
5529 	lctl = *ctl;
5530 	lctl.extra1 = &min_mtu;
5531 	lctl.extra2 = idev ? &idev->dev->mtu : NULL;
5532 
5533 	return proc_dointvec_minmax(&lctl, write, buffer, lenp, ppos);
5534 }
5535 
5536 static void dev_disable_change(struct inet6_dev *idev)
5537 {
5538 	struct netdev_notifier_info info;
5539 
5540 	if (!idev || !idev->dev)
5541 		return;
5542 
5543 	netdev_notifier_info_init(&info, idev->dev);
5544 	if (idev->cnf.disable_ipv6)
5545 		addrconf_notify(NULL, NETDEV_DOWN, &info);
5546 	else
5547 		addrconf_notify(NULL, NETDEV_UP, &info);
5548 }
5549 
5550 static void addrconf_disable_change(struct net *net, __s32 newf)
5551 {
5552 	struct net_device *dev;
5553 	struct inet6_dev *idev;
5554 
5555 	for_each_netdev(net, dev) {
5556 		idev = __in6_dev_get(dev);
5557 		if (idev) {
5558 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
5559 			idev->cnf.disable_ipv6 = newf;
5560 			if (changed)
5561 				dev_disable_change(idev);
5562 		}
5563 	}
5564 }
5565 
5566 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
5567 {
5568 	struct net *net;
5569 	int old;
5570 
5571 	if (!rtnl_trylock())
5572 		return restart_syscall();
5573 
5574 	net = (struct net *)table->extra2;
5575 	old = *p;
5576 	*p = newf;
5577 
5578 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
5579 		rtnl_unlock();
5580 		return 0;
5581 	}
5582 
5583 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
5584 		net->ipv6.devconf_dflt->disable_ipv6 = newf;
5585 		addrconf_disable_change(net, newf);
5586 	} else if ((!newf) ^ (!old))
5587 		dev_disable_change((struct inet6_dev *)table->extra1);
5588 
5589 	rtnl_unlock();
5590 	return 0;
5591 }
5592 
5593 static
5594 int addrconf_sysctl_disable(struct ctl_table *ctl, int write,
5595 			    void __user *buffer, size_t *lenp, loff_t *ppos)
5596 {
5597 	int *valp = ctl->data;
5598 	int val = *valp;
5599 	loff_t pos = *ppos;
5600 	struct ctl_table lctl;
5601 	int ret;
5602 
5603 	/*
5604 	 * ctl->data points to idev->cnf.disable_ipv6, we should
5605 	 * not modify it until we get the rtnl lock.
5606 	 */
5607 	lctl = *ctl;
5608 	lctl.data = &val;
5609 
5610 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5611 
5612 	if (write)
5613 		ret = addrconf_disable_ipv6(ctl, valp, val);
5614 	if (ret)
5615 		*ppos = pos;
5616 	return ret;
5617 }
5618 
5619 static
5620 int addrconf_sysctl_proxy_ndp(struct ctl_table *ctl, int write,
5621 			      void __user *buffer, size_t *lenp, loff_t *ppos)
5622 {
5623 	int *valp = ctl->data;
5624 	int ret;
5625 	int old, new;
5626 
5627 	old = *valp;
5628 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
5629 	new = *valp;
5630 
5631 	if (write && old != new) {
5632 		struct net *net = ctl->extra2;
5633 
5634 		if (!rtnl_trylock())
5635 			return restart_syscall();
5636 
5637 		if (valp == &net->ipv6.devconf_dflt->proxy_ndp)
5638 			inet6_netconf_notify_devconf(net, NETCONFA_PROXY_NEIGH,
5639 						     NETCONFA_IFINDEX_DEFAULT,
5640 						     net->ipv6.devconf_dflt);
5641 		else if (valp == &net->ipv6.devconf_all->proxy_ndp)
5642 			inet6_netconf_notify_devconf(net, NETCONFA_PROXY_NEIGH,
5643 						     NETCONFA_IFINDEX_ALL,
5644 						     net->ipv6.devconf_all);
5645 		else {
5646 			struct inet6_dev *idev = ctl->extra1;
5647 
5648 			inet6_netconf_notify_devconf(net, NETCONFA_PROXY_NEIGH,
5649 						     idev->dev->ifindex,
5650 						     &idev->cnf);
5651 		}
5652 		rtnl_unlock();
5653 	}
5654 
5655 	return ret;
5656 }
5657 
5658 static int addrconf_sysctl_stable_secret(struct ctl_table *ctl, int write,
5659 					 void __user *buffer, size_t *lenp,
5660 					 loff_t *ppos)
5661 {
5662 	int err;
5663 	struct in6_addr addr;
5664 	char str[IPV6_MAX_STRLEN];
5665 	struct ctl_table lctl = *ctl;
5666 	struct net *net = ctl->extra2;
5667 	struct ipv6_stable_secret *secret = ctl->data;
5668 
5669 	if (&net->ipv6.devconf_all->stable_secret == ctl->data)
5670 		return -EIO;
5671 
5672 	lctl.maxlen = IPV6_MAX_STRLEN;
5673 	lctl.data = str;
5674 
5675 	if (!rtnl_trylock())
5676 		return restart_syscall();
5677 
5678 	if (!write && !secret->initialized) {
5679 		err = -EIO;
5680 		goto out;
5681 	}
5682 
5683 	err = snprintf(str, sizeof(str), "%pI6", &secret->secret);
5684 	if (err >= sizeof(str)) {
5685 		err = -EIO;
5686 		goto out;
5687 	}
5688 
5689 	err = proc_dostring(&lctl, write, buffer, lenp, ppos);
5690 	if (err || !write)
5691 		goto out;
5692 
5693 	if (in6_pton(str, -1, addr.in6_u.u6_addr8, -1, NULL) != 1) {
5694 		err = -EIO;
5695 		goto out;
5696 	}
5697 
5698 	secret->initialized = true;
5699 	secret->secret = addr;
5700 
5701 	if (&net->ipv6.devconf_dflt->stable_secret == ctl->data) {
5702 		struct net_device *dev;
5703 
5704 		for_each_netdev(net, dev) {
5705 			struct inet6_dev *idev = __in6_dev_get(dev);
5706 
5707 			if (idev) {
5708 				idev->addr_gen_mode =
5709 					IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
5710 			}
5711 		}
5712 	} else {
5713 		struct inet6_dev *idev = ctl->extra1;
5714 
5715 		idev->addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
5716 	}
5717 
5718 out:
5719 	rtnl_unlock();
5720 
5721 	return err;
5722 }
5723 
5724 static
5725 int addrconf_sysctl_ignore_routes_with_linkdown(struct ctl_table *ctl,
5726 						int write,
5727 						void __user *buffer,
5728 						size_t *lenp,
5729 						loff_t *ppos)
5730 {
5731 	int *valp = ctl->data;
5732 	int val = *valp;
5733 	loff_t pos = *ppos;
5734 	struct ctl_table lctl;
5735 	int ret;
5736 
5737 	/* ctl->data points to idev->cnf.ignore_routes_when_linkdown
5738 	 * we should not modify it until we get the rtnl lock.
5739 	 */
5740 	lctl = *ctl;
5741 	lctl.data = &val;
5742 
5743 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5744 
5745 	if (write)
5746 		ret = addrconf_fixup_linkdown(ctl, valp, val);
5747 	if (ret)
5748 		*ppos = pos;
5749 	return ret;
5750 }
5751 
5752 static int minus_one = -1;
5753 static const int one = 1;
5754 static const int two_five_five = 255;
5755 
5756 static const struct ctl_table addrconf_sysctl[] = {
5757 	{
5758 		.procname	= "forwarding",
5759 		.data		= &ipv6_devconf.forwarding,
5760 		.maxlen		= sizeof(int),
5761 		.mode		= 0644,
5762 		.proc_handler	= addrconf_sysctl_forward,
5763 	},
5764 	{
5765 		.procname	= "hop_limit",
5766 		.data		= &ipv6_devconf.hop_limit,
5767 		.maxlen		= sizeof(int),
5768 		.mode		= 0644,
5769 		.proc_handler	= proc_dointvec_minmax,
5770 		.extra1		= (void *)&one,
5771 		.extra2		= (void *)&two_five_five,
5772 	},
5773 	{
5774 		.procname	= "mtu",
5775 		.data		= &ipv6_devconf.mtu6,
5776 		.maxlen		= sizeof(int),
5777 		.mode		= 0644,
5778 		.proc_handler	= addrconf_sysctl_mtu,
5779 	},
5780 	{
5781 		.procname	= "accept_ra",
5782 		.data		= &ipv6_devconf.accept_ra,
5783 		.maxlen		= sizeof(int),
5784 		.mode		= 0644,
5785 		.proc_handler	= proc_dointvec,
5786 	},
5787 	{
5788 		.procname	= "accept_redirects",
5789 		.data		= &ipv6_devconf.accept_redirects,
5790 		.maxlen		= sizeof(int),
5791 		.mode		= 0644,
5792 		.proc_handler	= proc_dointvec,
5793 	},
5794 	{
5795 		.procname	= "autoconf",
5796 		.data		= &ipv6_devconf.autoconf,
5797 		.maxlen		= sizeof(int),
5798 		.mode		= 0644,
5799 		.proc_handler	= proc_dointvec,
5800 	},
5801 	{
5802 		.procname	= "dad_transmits",
5803 		.data		= &ipv6_devconf.dad_transmits,
5804 		.maxlen		= sizeof(int),
5805 		.mode		= 0644,
5806 		.proc_handler	= proc_dointvec,
5807 	},
5808 	{
5809 		.procname	= "router_solicitations",
5810 		.data		= &ipv6_devconf.rtr_solicits,
5811 		.maxlen		= sizeof(int),
5812 		.mode		= 0644,
5813 		.proc_handler	= proc_dointvec_minmax,
5814 		.extra1		= &minus_one,
5815 	},
5816 	{
5817 		.procname	= "router_solicitation_interval",
5818 		.data		= &ipv6_devconf.rtr_solicit_interval,
5819 		.maxlen		= sizeof(int),
5820 		.mode		= 0644,
5821 		.proc_handler	= proc_dointvec_jiffies,
5822 	},
5823 	{
5824 		.procname	= "router_solicitation_max_interval",
5825 		.data		= &ipv6_devconf.rtr_solicit_max_interval,
5826 		.maxlen		= sizeof(int),
5827 		.mode		= 0644,
5828 		.proc_handler	= proc_dointvec_jiffies,
5829 	},
5830 	{
5831 		.procname	= "router_solicitation_delay",
5832 		.data		= &ipv6_devconf.rtr_solicit_delay,
5833 		.maxlen		= sizeof(int),
5834 		.mode		= 0644,
5835 		.proc_handler	= proc_dointvec_jiffies,
5836 	},
5837 	{
5838 		.procname	= "force_mld_version",
5839 		.data		= &ipv6_devconf.force_mld_version,
5840 		.maxlen		= sizeof(int),
5841 		.mode		= 0644,
5842 		.proc_handler	= proc_dointvec,
5843 	},
5844 	{
5845 		.procname	= "mldv1_unsolicited_report_interval",
5846 		.data		=
5847 			&ipv6_devconf.mldv1_unsolicited_report_interval,
5848 		.maxlen		= sizeof(int),
5849 		.mode		= 0644,
5850 		.proc_handler	= proc_dointvec_ms_jiffies,
5851 	},
5852 	{
5853 		.procname	= "mldv2_unsolicited_report_interval",
5854 		.data		=
5855 			&ipv6_devconf.mldv2_unsolicited_report_interval,
5856 		.maxlen		= sizeof(int),
5857 		.mode		= 0644,
5858 		.proc_handler	= proc_dointvec_ms_jiffies,
5859 	},
5860 	{
5861 		.procname	= "use_tempaddr",
5862 		.data		= &ipv6_devconf.use_tempaddr,
5863 		.maxlen		= sizeof(int),
5864 		.mode		= 0644,
5865 		.proc_handler	= proc_dointvec,
5866 	},
5867 	{
5868 		.procname	= "temp_valid_lft",
5869 		.data		= &ipv6_devconf.temp_valid_lft,
5870 		.maxlen		= sizeof(int),
5871 		.mode		= 0644,
5872 		.proc_handler	= proc_dointvec,
5873 	},
5874 	{
5875 		.procname	= "temp_prefered_lft",
5876 		.data		= &ipv6_devconf.temp_prefered_lft,
5877 		.maxlen		= sizeof(int),
5878 		.mode		= 0644,
5879 		.proc_handler	= proc_dointvec,
5880 	},
5881 	{
5882 		.procname	= "regen_max_retry",
5883 		.data		= &ipv6_devconf.regen_max_retry,
5884 		.maxlen		= sizeof(int),
5885 		.mode		= 0644,
5886 		.proc_handler	= proc_dointvec,
5887 	},
5888 	{
5889 		.procname	= "max_desync_factor",
5890 		.data		= &ipv6_devconf.max_desync_factor,
5891 		.maxlen		= sizeof(int),
5892 		.mode		= 0644,
5893 		.proc_handler	= proc_dointvec,
5894 	},
5895 	{
5896 		.procname	= "max_addresses",
5897 		.data		= &ipv6_devconf.max_addresses,
5898 		.maxlen		= sizeof(int),
5899 		.mode		= 0644,
5900 		.proc_handler	= proc_dointvec,
5901 	},
5902 	{
5903 		.procname	= "accept_ra_defrtr",
5904 		.data		= &ipv6_devconf.accept_ra_defrtr,
5905 		.maxlen		= sizeof(int),
5906 		.mode		= 0644,
5907 		.proc_handler	= proc_dointvec,
5908 	},
5909 	{
5910 		.procname	= "accept_ra_min_hop_limit",
5911 		.data		= &ipv6_devconf.accept_ra_min_hop_limit,
5912 		.maxlen		= sizeof(int),
5913 		.mode		= 0644,
5914 		.proc_handler	= proc_dointvec,
5915 	},
5916 	{
5917 		.procname	= "accept_ra_pinfo",
5918 		.data		= &ipv6_devconf.accept_ra_pinfo,
5919 		.maxlen		= sizeof(int),
5920 		.mode		= 0644,
5921 		.proc_handler	= proc_dointvec,
5922 	},
5923 #ifdef CONFIG_IPV6_ROUTER_PREF
5924 	{
5925 		.procname	= "accept_ra_rtr_pref",
5926 		.data		= &ipv6_devconf.accept_ra_rtr_pref,
5927 		.maxlen		= sizeof(int),
5928 		.mode		= 0644,
5929 		.proc_handler	= proc_dointvec,
5930 	},
5931 	{
5932 		.procname	= "router_probe_interval",
5933 		.data		= &ipv6_devconf.rtr_probe_interval,
5934 		.maxlen		= sizeof(int),
5935 		.mode		= 0644,
5936 		.proc_handler	= proc_dointvec_jiffies,
5937 	},
5938 #ifdef CONFIG_IPV6_ROUTE_INFO
5939 	{
5940 		.procname	= "accept_ra_rt_info_max_plen",
5941 		.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
5942 		.maxlen		= sizeof(int),
5943 		.mode		= 0644,
5944 		.proc_handler	= proc_dointvec,
5945 	},
5946 #endif
5947 #endif
5948 	{
5949 		.procname	= "proxy_ndp",
5950 		.data		= &ipv6_devconf.proxy_ndp,
5951 		.maxlen		= sizeof(int),
5952 		.mode		= 0644,
5953 		.proc_handler	= addrconf_sysctl_proxy_ndp,
5954 	},
5955 	{
5956 		.procname	= "accept_source_route",
5957 		.data		= &ipv6_devconf.accept_source_route,
5958 		.maxlen		= sizeof(int),
5959 		.mode		= 0644,
5960 		.proc_handler	= proc_dointvec,
5961 	},
5962 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
5963 	{
5964 		.procname	= "optimistic_dad",
5965 		.data		= &ipv6_devconf.optimistic_dad,
5966 		.maxlen		= sizeof(int),
5967 		.mode		= 0644,
5968 		.proc_handler   = proc_dointvec,
5969 	},
5970 	{
5971 		.procname	= "use_optimistic",
5972 		.data		= &ipv6_devconf.use_optimistic,
5973 		.maxlen		= sizeof(int),
5974 		.mode		= 0644,
5975 		.proc_handler	= proc_dointvec,
5976 	},
5977 #endif
5978 #ifdef CONFIG_IPV6_MROUTE
5979 	{
5980 		.procname	= "mc_forwarding",
5981 		.data		= &ipv6_devconf.mc_forwarding,
5982 		.maxlen		= sizeof(int),
5983 		.mode		= 0444,
5984 		.proc_handler	= proc_dointvec,
5985 	},
5986 #endif
5987 	{
5988 		.procname	= "disable_ipv6",
5989 		.data		= &ipv6_devconf.disable_ipv6,
5990 		.maxlen		= sizeof(int),
5991 		.mode		= 0644,
5992 		.proc_handler	= addrconf_sysctl_disable,
5993 	},
5994 	{
5995 		.procname	= "accept_dad",
5996 		.data		= &ipv6_devconf.accept_dad,
5997 		.maxlen		= sizeof(int),
5998 		.mode		= 0644,
5999 		.proc_handler	= proc_dointvec,
6000 	},
6001 	{
6002 		.procname	= "force_tllao",
6003 		.data		= &ipv6_devconf.force_tllao,
6004 		.maxlen		= sizeof(int),
6005 		.mode		= 0644,
6006 		.proc_handler	= proc_dointvec
6007 	},
6008 	{
6009 		.procname	= "ndisc_notify",
6010 		.data		= &ipv6_devconf.ndisc_notify,
6011 		.maxlen		= sizeof(int),
6012 		.mode		= 0644,
6013 		.proc_handler	= proc_dointvec
6014 	},
6015 	{
6016 		.procname	= "suppress_frag_ndisc",
6017 		.data		= &ipv6_devconf.suppress_frag_ndisc,
6018 		.maxlen		= sizeof(int),
6019 		.mode		= 0644,
6020 		.proc_handler	= proc_dointvec
6021 	},
6022 	{
6023 		.procname	= "accept_ra_from_local",
6024 		.data		= &ipv6_devconf.accept_ra_from_local,
6025 		.maxlen		= sizeof(int),
6026 		.mode		= 0644,
6027 		.proc_handler	= proc_dointvec,
6028 	},
6029 	{
6030 		.procname	= "accept_ra_mtu",
6031 		.data		= &ipv6_devconf.accept_ra_mtu,
6032 		.maxlen		= sizeof(int),
6033 		.mode		= 0644,
6034 		.proc_handler	= proc_dointvec,
6035 	},
6036 	{
6037 		.procname	= "stable_secret",
6038 		.data		= &ipv6_devconf.stable_secret,
6039 		.maxlen		= IPV6_MAX_STRLEN,
6040 		.mode		= 0600,
6041 		.proc_handler	= addrconf_sysctl_stable_secret,
6042 	},
6043 	{
6044 		.procname	= "use_oif_addrs_only",
6045 		.data		= &ipv6_devconf.use_oif_addrs_only,
6046 		.maxlen		= sizeof(int),
6047 		.mode		= 0644,
6048 		.proc_handler	= proc_dointvec,
6049 	},
6050 	{
6051 		.procname	= "ignore_routes_with_linkdown",
6052 		.data		= &ipv6_devconf.ignore_routes_with_linkdown,
6053 		.maxlen		= sizeof(int),
6054 		.mode		= 0644,
6055 		.proc_handler	= addrconf_sysctl_ignore_routes_with_linkdown,
6056 	},
6057 	{
6058 		.procname	= "drop_unicast_in_l2_multicast",
6059 		.data		= &ipv6_devconf.drop_unicast_in_l2_multicast,
6060 		.maxlen		= sizeof(int),
6061 		.mode		= 0644,
6062 		.proc_handler	= proc_dointvec,
6063 	},
6064 	{
6065 		.procname	= "drop_unsolicited_na",
6066 		.data		= &ipv6_devconf.drop_unsolicited_na,
6067 		.maxlen		= sizeof(int),
6068 		.mode		= 0644,
6069 		.proc_handler	= proc_dointvec,
6070 	},
6071 	{
6072 		.procname	= "keep_addr_on_down",
6073 		.data		= &ipv6_devconf.keep_addr_on_down,
6074 		.maxlen		= sizeof(int),
6075 		.mode		= 0644,
6076 		.proc_handler	= proc_dointvec,
6077 
6078 	},
6079 	{
6080 		.procname	= "seg6_enabled",
6081 		.data		= &ipv6_devconf.seg6_enabled,
6082 		.maxlen		= sizeof(int),
6083 		.mode		= 0644,
6084 		.proc_handler	= proc_dointvec,
6085 	},
6086 #ifdef CONFIG_IPV6_SEG6_HMAC
6087 	{
6088 		.procname	= "seg6_require_hmac",
6089 		.data		= &ipv6_devconf.seg6_require_hmac,
6090 		.maxlen		= sizeof(int),
6091 		.mode		= 0644,
6092 		.proc_handler	= proc_dointvec,
6093 	},
6094 #endif
6095 	{
6096 		.procname       = "enhanced_dad",
6097 		.data           = &ipv6_devconf.enhanced_dad,
6098 		.maxlen         = sizeof(int),
6099 		.mode           = 0644,
6100 		.proc_handler   = proc_dointvec,
6101 	},
6102 	{
6103 		/* sentinel */
6104 	}
6105 };
6106 
6107 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
6108 		struct inet6_dev *idev, struct ipv6_devconf *p)
6109 {
6110 	int i, ifindex;
6111 	struct ctl_table *table;
6112 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
6113 
6114 	table = kmemdup(addrconf_sysctl, sizeof(addrconf_sysctl), GFP_KERNEL);
6115 	if (!table)
6116 		goto out;
6117 
6118 	for (i = 0; table[i].data; i++) {
6119 		table[i].data += (char *)p - (char *)&ipv6_devconf;
6120 		/* If one of these is already set, then it is not safe to
6121 		 * overwrite either of them: this makes proc_dointvec_minmax
6122 		 * usable.
6123 		 */
6124 		if (!table[i].extra1 && !table[i].extra2) {
6125 			table[i].extra1 = idev; /* embedded; no ref */
6126 			table[i].extra2 = net;
6127 		}
6128 	}
6129 
6130 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
6131 
6132 	p->sysctl_header = register_net_sysctl(net, path, table);
6133 	if (!p->sysctl_header)
6134 		goto free;
6135 
6136 	if (!strcmp(dev_name, "all"))
6137 		ifindex = NETCONFA_IFINDEX_ALL;
6138 	else if (!strcmp(dev_name, "default"))
6139 		ifindex = NETCONFA_IFINDEX_DEFAULT;
6140 	else
6141 		ifindex = idev->dev->ifindex;
6142 	inet6_netconf_notify_devconf(net, NETCONFA_ALL, ifindex, p);
6143 	return 0;
6144 
6145 free:
6146 	kfree(table);
6147 out:
6148 	return -ENOBUFS;
6149 }
6150 
6151 static void __addrconf_sysctl_unregister(struct ipv6_devconf *p)
6152 {
6153 	struct ctl_table *table;
6154 
6155 	if (!p->sysctl_header)
6156 		return;
6157 
6158 	table = p->sysctl_header->ctl_table_arg;
6159 	unregister_net_sysctl_table(p->sysctl_header);
6160 	p->sysctl_header = NULL;
6161 	kfree(table);
6162 }
6163 
6164 static int addrconf_sysctl_register(struct inet6_dev *idev)
6165 {
6166 	int err;
6167 
6168 	if (!sysctl_dev_name_is_allowed(idev->dev->name))
6169 		return -EINVAL;
6170 
6171 	err = neigh_sysctl_register(idev->dev, idev->nd_parms,
6172 				    &ndisc_ifinfo_sysctl_change);
6173 	if (err)
6174 		return err;
6175 	err = __addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
6176 					 idev, &idev->cnf);
6177 	if (err)
6178 		neigh_sysctl_unregister(idev->nd_parms);
6179 
6180 	return err;
6181 }
6182 
6183 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
6184 {
6185 	__addrconf_sysctl_unregister(&idev->cnf);
6186 	neigh_sysctl_unregister(idev->nd_parms);
6187 }
6188 
6189 
6190 #endif
6191 
6192 static int __net_init addrconf_init_net(struct net *net)
6193 {
6194 	int err = -ENOMEM;
6195 	struct ipv6_devconf *all, *dflt;
6196 
6197 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
6198 	if (!all)
6199 		goto err_alloc_all;
6200 
6201 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
6202 	if (!dflt)
6203 		goto err_alloc_dflt;
6204 
6205 	/* these will be inherited by all namespaces */
6206 	dflt->autoconf = ipv6_defaults.autoconf;
6207 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
6208 
6209 	dflt->stable_secret.initialized = false;
6210 	all->stable_secret.initialized = false;
6211 
6212 	net->ipv6.devconf_all = all;
6213 	net->ipv6.devconf_dflt = dflt;
6214 
6215 #ifdef CONFIG_SYSCTL
6216 	err = __addrconf_sysctl_register(net, "all", NULL, all);
6217 	if (err < 0)
6218 		goto err_reg_all;
6219 
6220 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
6221 	if (err < 0)
6222 		goto err_reg_dflt;
6223 #endif
6224 	return 0;
6225 
6226 #ifdef CONFIG_SYSCTL
6227 err_reg_dflt:
6228 	__addrconf_sysctl_unregister(all);
6229 err_reg_all:
6230 	kfree(dflt);
6231 #endif
6232 err_alloc_dflt:
6233 	kfree(all);
6234 err_alloc_all:
6235 	return err;
6236 }
6237 
6238 static void __net_exit addrconf_exit_net(struct net *net)
6239 {
6240 #ifdef CONFIG_SYSCTL
6241 	__addrconf_sysctl_unregister(net->ipv6.devconf_dflt);
6242 	__addrconf_sysctl_unregister(net->ipv6.devconf_all);
6243 #endif
6244 	kfree(net->ipv6.devconf_dflt);
6245 	kfree(net->ipv6.devconf_all);
6246 }
6247 
6248 static struct pernet_operations addrconf_ops = {
6249 	.init = addrconf_init_net,
6250 	.exit = addrconf_exit_net,
6251 };
6252 
6253 static struct rtnl_af_ops inet6_ops __read_mostly = {
6254 	.family		  = AF_INET6,
6255 	.fill_link_af	  = inet6_fill_link_af,
6256 	.get_link_af_size = inet6_get_link_af_size,
6257 	.validate_link_af = inet6_validate_link_af,
6258 	.set_link_af	  = inet6_set_link_af,
6259 };
6260 
6261 /*
6262  *	Init / cleanup code
6263  */
6264 
6265 int __init addrconf_init(void)
6266 {
6267 	struct inet6_dev *idev;
6268 	int i, err;
6269 
6270 	err = ipv6_addr_label_init();
6271 	if (err < 0) {
6272 		pr_crit("%s: cannot initialize default policy table: %d\n",
6273 			__func__, err);
6274 		goto out;
6275 	}
6276 
6277 	err = register_pernet_subsys(&addrconf_ops);
6278 	if (err < 0)
6279 		goto out_addrlabel;
6280 
6281 	addrconf_wq = create_workqueue("ipv6_addrconf");
6282 	if (!addrconf_wq) {
6283 		err = -ENOMEM;
6284 		goto out_nowq;
6285 	}
6286 
6287 	/* The addrconf netdev notifier requires that loopback_dev
6288 	 * has it's ipv6 private information allocated and setup
6289 	 * before it can bring up and give link-local addresses
6290 	 * to other devices which are up.
6291 	 *
6292 	 * Unfortunately, loopback_dev is not necessarily the first
6293 	 * entry in the global dev_base list of net devices.  In fact,
6294 	 * it is likely to be the very last entry on that list.
6295 	 * So this causes the notifier registry below to try and
6296 	 * give link-local addresses to all devices besides loopback_dev
6297 	 * first, then loopback_dev, which cases all the non-loopback_dev
6298 	 * devices to fail to get a link-local address.
6299 	 *
6300 	 * So, as a temporary fix, allocate the ipv6 structure for
6301 	 * loopback_dev first by hand.
6302 	 * Longer term, all of the dependencies ipv6 has upon the loopback
6303 	 * device and it being up should be removed.
6304 	 */
6305 	rtnl_lock();
6306 	idev = ipv6_add_dev(init_net.loopback_dev);
6307 	rtnl_unlock();
6308 	if (IS_ERR(idev)) {
6309 		err = PTR_ERR(idev);
6310 		goto errlo;
6311 	}
6312 
6313 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
6314 		INIT_HLIST_HEAD(&inet6_addr_lst[i]);
6315 
6316 	register_netdevice_notifier(&ipv6_dev_notf);
6317 
6318 	addrconf_verify();
6319 
6320 	rtnl_af_register(&inet6_ops);
6321 
6322 	err = __rtnl_register(PF_INET6, RTM_GETLINK, NULL, inet6_dump_ifinfo,
6323 			      NULL);
6324 	if (err < 0)
6325 		goto errout;
6326 
6327 	/* Only the first call to __rtnl_register can fail */
6328 	__rtnl_register(PF_INET6, RTM_NEWADDR, inet6_rtm_newaddr, NULL, NULL);
6329 	__rtnl_register(PF_INET6, RTM_DELADDR, inet6_rtm_deladdr, NULL, NULL);
6330 	__rtnl_register(PF_INET6, RTM_GETADDR, inet6_rtm_getaddr,
6331 			inet6_dump_ifaddr, NULL);
6332 	__rtnl_register(PF_INET6, RTM_GETMULTICAST, NULL,
6333 			inet6_dump_ifmcaddr, NULL);
6334 	__rtnl_register(PF_INET6, RTM_GETANYCAST, NULL,
6335 			inet6_dump_ifacaddr, NULL);
6336 	__rtnl_register(PF_INET6, RTM_GETNETCONF, inet6_netconf_get_devconf,
6337 			inet6_netconf_dump_devconf, NULL);
6338 
6339 	ipv6_addr_label_rtnl_register();
6340 
6341 	return 0;
6342 errout:
6343 	rtnl_af_unregister(&inet6_ops);
6344 	unregister_netdevice_notifier(&ipv6_dev_notf);
6345 errlo:
6346 	destroy_workqueue(addrconf_wq);
6347 out_nowq:
6348 	unregister_pernet_subsys(&addrconf_ops);
6349 out_addrlabel:
6350 	ipv6_addr_label_cleanup();
6351 out:
6352 	return err;
6353 }
6354 
6355 void addrconf_cleanup(void)
6356 {
6357 	struct net_device *dev;
6358 	int i;
6359 
6360 	unregister_netdevice_notifier(&ipv6_dev_notf);
6361 	unregister_pernet_subsys(&addrconf_ops);
6362 	ipv6_addr_label_cleanup();
6363 
6364 	rtnl_lock();
6365 
6366 	__rtnl_af_unregister(&inet6_ops);
6367 
6368 	/* clean dev list */
6369 	for_each_netdev(&init_net, dev) {
6370 		if (__in6_dev_get(dev) == NULL)
6371 			continue;
6372 		addrconf_ifdown(dev, 1);
6373 	}
6374 	addrconf_ifdown(init_net.loopback_dev, 2);
6375 
6376 	/*
6377 	 *	Check hash table.
6378 	 */
6379 	spin_lock_bh(&addrconf_hash_lock);
6380 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
6381 		WARN_ON(!hlist_empty(&inet6_addr_lst[i]));
6382 	spin_unlock_bh(&addrconf_hash_lock);
6383 	cancel_delayed_work(&addr_chk_work);
6384 	rtnl_unlock();
6385 
6386 	destroy_workqueue(addrconf_wq);
6387 }
6388