xref: /openbmc/linux/net/ipv6/addrconf.c (revision a0ae2562c6c4b2721d9fddba63b7286c13517d9f)
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/sched/signal.h>
47 #include <linux/socket.h>
48 #include <linux/sockios.h>
49 #include <linux/net.h>
50 #include <linux/inet.h>
51 #include <linux/in6.h>
52 #include <linux/netdevice.h>
53 #include <linux/if_addr.h>
54 #include <linux/if_arp.h>
55 #include <linux/if_arcnet.h>
56 #include <linux/if_infiniband.h>
57 #include <linux/route.h>
58 #include <linux/inetdevice.h>
59 #include <linux/init.h>
60 #include <linux/slab.h>
61 #ifdef CONFIG_SYSCTL
62 #include <linux/sysctl.h>
63 #endif
64 #include <linux/capability.h>
65 #include <linux/delay.h>
66 #include <linux/notifier.h>
67 #include <linux/string.h>
68 #include <linux/hash.h>
69 
70 #include <net/net_namespace.h>
71 #include <net/sock.h>
72 #include <net/snmp.h>
73 
74 #include <net/6lowpan.h>
75 #include <net/firewire.h>
76 #include <net/ipv6.h>
77 #include <net/protocol.h>
78 #include <net/ndisc.h>
79 #include <net/ip6_route.h>
80 #include <net/addrconf.h>
81 #include <net/tcp.h>
82 #include <net/ip.h>
83 #include <net/netlink.h>
84 #include <net/pkt_sched.h>
85 #include <net/l3mdev.h>
86 #include <linux/if_tunnel.h>
87 #include <linux/rtnetlink.h>
88 #include <linux/netconf.h>
89 #include <linux/random.h>
90 #include <linux/uaccess.h>
91 #include <asm/unaligned.h>
92 
93 #include <linux/proc_fs.h>
94 #include <linux/seq_file.h>
95 #include <linux/export.h>
96 
97 #define	INFINITY_LIFE_TIME	0xFFFFFFFF
98 
99 #define IPV6_MAX_STRLEN \
100 	sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255")
101 
102 static inline u32 cstamp_delta(unsigned long cstamp)
103 {
104 	return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
105 }
106 
107 static inline s32 rfc3315_s14_backoff_init(s32 irt)
108 {
109 	/* multiply 'initial retransmission time' by 0.9 .. 1.1 */
110 	u64 tmp = (900000 + prandom_u32() % 200001) * (u64)irt;
111 	do_div(tmp, 1000000);
112 	return (s32)tmp;
113 }
114 
115 static inline s32 rfc3315_s14_backoff_update(s32 rt, s32 mrt)
116 {
117 	/* multiply 'retransmission timeout' by 1.9 .. 2.1 */
118 	u64 tmp = (1900000 + prandom_u32() % 200001) * (u64)rt;
119 	do_div(tmp, 1000000);
120 	if ((s32)tmp > mrt) {
121 		/* multiply 'maximum retransmission time' by 0.9 .. 1.1 */
122 		tmp = (900000 + prandom_u32() % 200001) * (u64)mrt;
123 		do_div(tmp, 1000000);
124 	}
125 	return (s32)tmp;
126 }
127 
128 #ifdef CONFIG_SYSCTL
129 static int addrconf_sysctl_register(struct inet6_dev *idev);
130 static void addrconf_sysctl_unregister(struct inet6_dev *idev);
131 #else
132 static inline int addrconf_sysctl_register(struct inet6_dev *idev)
133 {
134 	return 0;
135 }
136 
137 static inline void addrconf_sysctl_unregister(struct inet6_dev *idev)
138 {
139 }
140 #endif
141 
142 static void ipv6_regen_rndid(struct inet6_dev *idev);
143 static void ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr);
144 
145 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev);
146 static int ipv6_count_addresses(const struct inet6_dev *idev);
147 static int ipv6_generate_stable_address(struct in6_addr *addr,
148 					u8 dad_count,
149 					const struct inet6_dev *idev);
150 
151 #define IN6_ADDR_HSIZE_SHIFT	8
152 #define IN6_ADDR_HSIZE		(1 << IN6_ADDR_HSIZE_SHIFT)
153 /*
154  *	Configured unicast address hash table
155  */
156 static struct hlist_head inet6_addr_lst[IN6_ADDR_HSIZE];
157 static DEFINE_SPINLOCK(addrconf_hash_lock);
158 
159 static void addrconf_verify(void);
160 static void addrconf_verify_rtnl(void);
161 static void addrconf_verify_work(struct work_struct *);
162 
163 static struct workqueue_struct *addrconf_wq;
164 static DECLARE_DELAYED_WORK(addr_chk_work, addrconf_verify_work);
165 
166 static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
167 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
168 
169 static void addrconf_type_change(struct net_device *dev,
170 				 unsigned long event);
171 static int addrconf_ifdown(struct net_device *dev, int how);
172 
173 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
174 						  int plen,
175 						  const struct net_device *dev,
176 						  u32 flags, u32 noflags);
177 
178 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
179 static void addrconf_dad_work(struct work_struct *w);
180 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
181 				   bool send_na);
182 static void addrconf_dad_run(struct inet6_dev *idev);
183 static void addrconf_rs_timer(struct timer_list *t);
184 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
185 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
186 
187 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
188 				struct prefix_info *pinfo);
189 
190 static struct ipv6_devconf ipv6_devconf __read_mostly = {
191 	.forwarding		= 0,
192 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
193 	.mtu6			= IPV6_MIN_MTU,
194 	.accept_ra		= 1,
195 	.accept_redirects	= 1,
196 	.autoconf		= 1,
197 	.force_mld_version	= 0,
198 	.mldv1_unsolicited_report_interval = 10 * HZ,
199 	.mldv2_unsolicited_report_interval = HZ,
200 	.dad_transmits		= 1,
201 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
202 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
203 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
204 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
205 	.use_tempaddr		= 0,
206 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
207 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
208 	.regen_max_retry	= REGEN_MAX_RETRY,
209 	.max_desync_factor	= MAX_DESYNC_FACTOR,
210 	.max_addresses		= IPV6_MAX_ADDRESSES,
211 	.accept_ra_defrtr	= 1,
212 	.accept_ra_from_local	= 0,
213 	.accept_ra_min_hop_limit= 1,
214 	.accept_ra_pinfo	= 1,
215 #ifdef CONFIG_IPV6_ROUTER_PREF
216 	.accept_ra_rtr_pref	= 1,
217 	.rtr_probe_interval	= 60 * HZ,
218 #ifdef CONFIG_IPV6_ROUTE_INFO
219 	.accept_ra_rt_info_min_plen = 0,
220 	.accept_ra_rt_info_max_plen = 0,
221 #endif
222 #endif
223 	.proxy_ndp		= 0,
224 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
225 	.disable_ipv6		= 0,
226 	.accept_dad		= 0,
227 	.suppress_frag_ndisc	= 1,
228 	.accept_ra_mtu		= 1,
229 	.stable_secret		= {
230 		.initialized = false,
231 	},
232 	.use_oif_addrs_only	= 0,
233 	.ignore_routes_with_linkdown = 0,
234 	.keep_addr_on_down	= 0,
235 	.seg6_enabled		= 0,
236 #ifdef CONFIG_IPV6_SEG6_HMAC
237 	.seg6_require_hmac	= 0,
238 #endif
239 	.enhanced_dad           = 1,
240 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
241 	.disable_policy		= 0,
242 };
243 
244 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
245 	.forwarding		= 0,
246 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
247 	.mtu6			= IPV6_MIN_MTU,
248 	.accept_ra		= 1,
249 	.accept_redirects	= 1,
250 	.autoconf		= 1,
251 	.force_mld_version	= 0,
252 	.mldv1_unsolicited_report_interval = 10 * HZ,
253 	.mldv2_unsolicited_report_interval = HZ,
254 	.dad_transmits		= 1,
255 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
256 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
257 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
258 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
259 	.use_tempaddr		= 0,
260 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
261 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
262 	.regen_max_retry	= REGEN_MAX_RETRY,
263 	.max_desync_factor	= MAX_DESYNC_FACTOR,
264 	.max_addresses		= IPV6_MAX_ADDRESSES,
265 	.accept_ra_defrtr	= 1,
266 	.accept_ra_from_local	= 0,
267 	.accept_ra_min_hop_limit= 1,
268 	.accept_ra_pinfo	= 1,
269 #ifdef CONFIG_IPV6_ROUTER_PREF
270 	.accept_ra_rtr_pref	= 1,
271 	.rtr_probe_interval	= 60 * HZ,
272 #ifdef CONFIG_IPV6_ROUTE_INFO
273 	.accept_ra_rt_info_min_plen = 0,
274 	.accept_ra_rt_info_max_plen = 0,
275 #endif
276 #endif
277 	.proxy_ndp		= 0,
278 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
279 	.disable_ipv6		= 0,
280 	.accept_dad		= 1,
281 	.suppress_frag_ndisc	= 1,
282 	.accept_ra_mtu		= 1,
283 	.stable_secret		= {
284 		.initialized = false,
285 	},
286 	.use_oif_addrs_only	= 0,
287 	.ignore_routes_with_linkdown = 0,
288 	.keep_addr_on_down	= 0,
289 	.seg6_enabled		= 0,
290 #ifdef CONFIG_IPV6_SEG6_HMAC
291 	.seg6_require_hmac	= 0,
292 #endif
293 	.enhanced_dad           = 1,
294 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
295 	.disable_policy		= 0,
296 };
297 
298 /* Check if link is ready: is it up and is a valid qdisc available */
299 static inline bool addrconf_link_ready(const struct net_device *dev)
300 {
301 	return netif_oper_up(dev) && !qdisc_tx_is_noop(dev);
302 }
303 
304 static void addrconf_del_rs_timer(struct inet6_dev *idev)
305 {
306 	if (del_timer(&idev->rs_timer))
307 		__in6_dev_put(idev);
308 }
309 
310 static void addrconf_del_dad_work(struct inet6_ifaddr *ifp)
311 {
312 	if (cancel_delayed_work(&ifp->dad_work))
313 		__in6_ifa_put(ifp);
314 }
315 
316 static void addrconf_mod_rs_timer(struct inet6_dev *idev,
317 				  unsigned long when)
318 {
319 	if (!timer_pending(&idev->rs_timer))
320 		in6_dev_hold(idev);
321 	mod_timer(&idev->rs_timer, jiffies + when);
322 }
323 
324 static void addrconf_mod_dad_work(struct inet6_ifaddr *ifp,
325 				   unsigned long delay)
326 {
327 	in6_ifa_hold(ifp);
328 	if (mod_delayed_work(addrconf_wq, &ifp->dad_work, delay))
329 		in6_ifa_put(ifp);
330 }
331 
332 static int snmp6_alloc_dev(struct inet6_dev *idev)
333 {
334 	int i;
335 
336 	idev->stats.ipv6 = alloc_percpu(struct ipstats_mib);
337 	if (!idev->stats.ipv6)
338 		goto err_ip;
339 
340 	for_each_possible_cpu(i) {
341 		struct ipstats_mib *addrconf_stats;
342 		addrconf_stats = per_cpu_ptr(idev->stats.ipv6, i);
343 		u64_stats_init(&addrconf_stats->syncp);
344 	}
345 
346 
347 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
348 					GFP_KERNEL);
349 	if (!idev->stats.icmpv6dev)
350 		goto err_icmp;
351 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
352 					   GFP_KERNEL);
353 	if (!idev->stats.icmpv6msgdev)
354 		goto err_icmpmsg;
355 
356 	return 0;
357 
358 err_icmpmsg:
359 	kfree(idev->stats.icmpv6dev);
360 err_icmp:
361 	free_percpu(idev->stats.ipv6);
362 err_ip:
363 	return -ENOMEM;
364 }
365 
366 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
367 {
368 	struct inet6_dev *ndev;
369 	int err = -ENOMEM;
370 
371 	ASSERT_RTNL();
372 
373 	if (dev->mtu < IPV6_MIN_MTU)
374 		return ERR_PTR(-EINVAL);
375 
376 	ndev = kzalloc(sizeof(struct inet6_dev), GFP_KERNEL);
377 	if (!ndev)
378 		return ERR_PTR(err);
379 
380 	rwlock_init(&ndev->lock);
381 	ndev->dev = dev;
382 	INIT_LIST_HEAD(&ndev->addr_list);
383 	timer_setup(&ndev->rs_timer, addrconf_rs_timer, 0);
384 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
385 
386 	if (ndev->cnf.stable_secret.initialized)
387 		ndev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
388 
389 	ndev->cnf.mtu6 = dev->mtu;
390 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
391 	if (!ndev->nd_parms) {
392 		kfree(ndev);
393 		return ERR_PTR(err);
394 	}
395 	if (ndev->cnf.forwarding)
396 		dev_disable_lro(dev);
397 	/* We refer to the device */
398 	dev_hold(dev);
399 
400 	if (snmp6_alloc_dev(ndev) < 0) {
401 		netdev_dbg(dev, "%s: cannot allocate memory for statistics\n",
402 			   __func__);
403 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
404 		dev_put(dev);
405 		kfree(ndev);
406 		return ERR_PTR(err);
407 	}
408 
409 	if (snmp6_register_dev(ndev) < 0) {
410 		netdev_dbg(dev, "%s: cannot create /proc/net/dev_snmp6/%s\n",
411 			   __func__, dev->name);
412 		goto err_release;
413 	}
414 
415 	/* One reference from device. */
416 	refcount_set(&ndev->refcnt, 1);
417 
418 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
419 		ndev->cnf.accept_dad = -1;
420 
421 #if IS_ENABLED(CONFIG_IPV6_SIT)
422 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
423 		pr_info("%s: Disabled Multicast RS\n", dev->name);
424 		ndev->cnf.rtr_solicits = 0;
425 	}
426 #endif
427 
428 	INIT_LIST_HEAD(&ndev->tempaddr_list);
429 	ndev->desync_factor = U32_MAX;
430 	if ((dev->flags&IFF_LOOPBACK) ||
431 	    dev->type == ARPHRD_TUNNEL ||
432 	    dev->type == ARPHRD_TUNNEL6 ||
433 	    dev->type == ARPHRD_SIT ||
434 	    dev->type == ARPHRD_NONE) {
435 		ndev->cnf.use_tempaddr = -1;
436 	} else
437 		ipv6_regen_rndid(ndev);
438 
439 	ndev->token = in6addr_any;
440 
441 	if (netif_running(dev) && addrconf_link_ready(dev))
442 		ndev->if_flags |= IF_READY;
443 
444 	ipv6_mc_init_dev(ndev);
445 	ndev->tstamp = jiffies;
446 	err = addrconf_sysctl_register(ndev);
447 	if (err) {
448 		ipv6_mc_destroy_dev(ndev);
449 		snmp6_unregister_dev(ndev);
450 		goto err_release;
451 	}
452 	/* protected by rtnl_lock */
453 	rcu_assign_pointer(dev->ip6_ptr, ndev);
454 
455 	/* Join interface-local all-node multicast group */
456 	ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes);
457 
458 	/* Join all-node multicast group */
459 	ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
460 
461 	/* Join all-router multicast group if forwarding is set */
462 	if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
463 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
464 
465 	return ndev;
466 
467 err_release:
468 	neigh_parms_release(&nd_tbl, ndev->nd_parms);
469 	ndev->dead = 1;
470 	in6_dev_finish_destroy(ndev);
471 	return ERR_PTR(err);
472 }
473 
474 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
475 {
476 	struct inet6_dev *idev;
477 
478 	ASSERT_RTNL();
479 
480 	idev = __in6_dev_get(dev);
481 	if (!idev) {
482 		idev = ipv6_add_dev(dev);
483 		if (IS_ERR(idev))
484 			return NULL;
485 	}
486 
487 	if (dev->flags&IFF_UP)
488 		ipv6_mc_up(idev);
489 	return idev;
490 }
491 
492 static int inet6_netconf_msgsize_devconf(int type)
493 {
494 	int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
495 		    + nla_total_size(4);	/* NETCONFA_IFINDEX */
496 	bool all = false;
497 
498 	if (type == NETCONFA_ALL)
499 		all = true;
500 
501 	if (all || type == NETCONFA_FORWARDING)
502 		size += nla_total_size(4);
503 #ifdef CONFIG_IPV6_MROUTE
504 	if (all || type == NETCONFA_MC_FORWARDING)
505 		size += nla_total_size(4);
506 #endif
507 	if (all || type == NETCONFA_PROXY_NEIGH)
508 		size += nla_total_size(4);
509 
510 	if (all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN)
511 		size += nla_total_size(4);
512 
513 	return size;
514 }
515 
516 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
517 				      struct ipv6_devconf *devconf, u32 portid,
518 				      u32 seq, int event, unsigned int flags,
519 				      int type)
520 {
521 	struct nlmsghdr  *nlh;
522 	struct netconfmsg *ncm;
523 	bool all = false;
524 
525 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
526 			flags);
527 	if (!nlh)
528 		return -EMSGSIZE;
529 
530 	if (type == NETCONFA_ALL)
531 		all = true;
532 
533 	ncm = nlmsg_data(nlh);
534 	ncm->ncm_family = AF_INET6;
535 
536 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
537 		goto nla_put_failure;
538 
539 	if (!devconf)
540 		goto out;
541 
542 	if ((all || type == NETCONFA_FORWARDING) &&
543 	    nla_put_s32(skb, NETCONFA_FORWARDING, devconf->forwarding) < 0)
544 		goto nla_put_failure;
545 #ifdef CONFIG_IPV6_MROUTE
546 	if ((all || type == NETCONFA_MC_FORWARDING) &&
547 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
548 			devconf->mc_forwarding) < 0)
549 		goto nla_put_failure;
550 #endif
551 	if ((all || type == NETCONFA_PROXY_NEIGH) &&
552 	    nla_put_s32(skb, NETCONFA_PROXY_NEIGH, devconf->proxy_ndp) < 0)
553 		goto nla_put_failure;
554 
555 	if ((all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN) &&
556 	    nla_put_s32(skb, NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
557 			devconf->ignore_routes_with_linkdown) < 0)
558 		goto nla_put_failure;
559 
560 out:
561 	nlmsg_end(skb, nlh);
562 	return 0;
563 
564 nla_put_failure:
565 	nlmsg_cancel(skb, nlh);
566 	return -EMSGSIZE;
567 }
568 
569 void inet6_netconf_notify_devconf(struct net *net, int event, int type,
570 				  int ifindex, struct ipv6_devconf *devconf)
571 {
572 	struct sk_buff *skb;
573 	int err = -ENOBUFS;
574 
575 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_KERNEL);
576 	if (!skb)
577 		goto errout;
578 
579 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
580 					 event, 0, type);
581 	if (err < 0) {
582 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
583 		WARN_ON(err == -EMSGSIZE);
584 		kfree_skb(skb);
585 		goto errout;
586 	}
587 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_KERNEL);
588 	return;
589 errout:
590 	rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
591 }
592 
593 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
594 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
595 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
596 	[NETCONFA_PROXY_NEIGH]	= { .len = sizeof(int) },
597 	[NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN]	= { .len = sizeof(int) },
598 };
599 
600 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
601 				     struct nlmsghdr *nlh,
602 				     struct netlink_ext_ack *extack)
603 {
604 	struct net *net = sock_net(in_skb->sk);
605 	struct nlattr *tb[NETCONFA_MAX+1];
606 	struct inet6_dev *in6_dev = NULL;
607 	struct net_device *dev = NULL;
608 	struct netconfmsg *ncm;
609 	struct sk_buff *skb;
610 	struct ipv6_devconf *devconf;
611 	int ifindex;
612 	int err;
613 
614 	err = nlmsg_parse(nlh, sizeof(*ncm), tb, NETCONFA_MAX,
615 			  devconf_ipv6_policy, extack);
616 	if (err < 0)
617 		return err;
618 
619 	if (!tb[NETCONFA_IFINDEX])
620 		return -EINVAL;
621 
622 	err = -EINVAL;
623 	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
624 	switch (ifindex) {
625 	case NETCONFA_IFINDEX_ALL:
626 		devconf = net->ipv6.devconf_all;
627 		break;
628 	case NETCONFA_IFINDEX_DEFAULT:
629 		devconf = net->ipv6.devconf_dflt;
630 		break;
631 	default:
632 		dev = dev_get_by_index(net, ifindex);
633 		if (!dev)
634 			return -EINVAL;
635 		in6_dev = in6_dev_get(dev);
636 		if (!in6_dev)
637 			goto errout;
638 		devconf = &in6_dev->cnf;
639 		break;
640 	}
641 
642 	err = -ENOBUFS;
643 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(NETCONFA_ALL), GFP_KERNEL);
644 	if (!skb)
645 		goto errout;
646 
647 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
648 					 NETLINK_CB(in_skb).portid,
649 					 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
650 					 NETCONFA_ALL);
651 	if (err < 0) {
652 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
653 		WARN_ON(err == -EMSGSIZE);
654 		kfree_skb(skb);
655 		goto errout;
656 	}
657 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
658 errout:
659 	if (in6_dev)
660 		in6_dev_put(in6_dev);
661 	if (dev)
662 		dev_put(dev);
663 	return err;
664 }
665 
666 static int inet6_netconf_dump_devconf(struct sk_buff *skb,
667 				      struct netlink_callback *cb)
668 {
669 	struct net *net = sock_net(skb->sk);
670 	int h, s_h;
671 	int idx, s_idx;
672 	struct net_device *dev;
673 	struct inet6_dev *idev;
674 	struct hlist_head *head;
675 
676 	s_h = cb->args[0];
677 	s_idx = idx = cb->args[1];
678 
679 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
680 		idx = 0;
681 		head = &net->dev_index_head[h];
682 		rcu_read_lock();
683 		cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^
684 			  net->dev_base_seq;
685 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
686 			if (idx < s_idx)
687 				goto cont;
688 			idev = __in6_dev_get(dev);
689 			if (!idev)
690 				goto cont;
691 
692 			if (inet6_netconf_fill_devconf(skb, dev->ifindex,
693 						       &idev->cnf,
694 						       NETLINK_CB(cb->skb).portid,
695 						       cb->nlh->nlmsg_seq,
696 						       RTM_NEWNETCONF,
697 						       NLM_F_MULTI,
698 						       NETCONFA_ALL) < 0) {
699 				rcu_read_unlock();
700 				goto done;
701 			}
702 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
703 cont:
704 			idx++;
705 		}
706 		rcu_read_unlock();
707 	}
708 	if (h == NETDEV_HASHENTRIES) {
709 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
710 					       net->ipv6.devconf_all,
711 					       NETLINK_CB(cb->skb).portid,
712 					       cb->nlh->nlmsg_seq,
713 					       RTM_NEWNETCONF, NLM_F_MULTI,
714 					       NETCONFA_ALL) < 0)
715 			goto done;
716 		else
717 			h++;
718 	}
719 	if (h == NETDEV_HASHENTRIES + 1) {
720 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
721 					       net->ipv6.devconf_dflt,
722 					       NETLINK_CB(cb->skb).portid,
723 					       cb->nlh->nlmsg_seq,
724 					       RTM_NEWNETCONF, NLM_F_MULTI,
725 					       NETCONFA_ALL) < 0)
726 			goto done;
727 		else
728 			h++;
729 	}
730 done:
731 	cb->args[0] = h;
732 	cb->args[1] = idx;
733 
734 	return skb->len;
735 }
736 
737 #ifdef CONFIG_SYSCTL
738 static void dev_forward_change(struct inet6_dev *idev)
739 {
740 	struct net_device *dev;
741 	struct inet6_ifaddr *ifa;
742 
743 	if (!idev)
744 		return;
745 	dev = idev->dev;
746 	if (idev->cnf.forwarding)
747 		dev_disable_lro(dev);
748 	if (dev->flags & IFF_MULTICAST) {
749 		if (idev->cnf.forwarding) {
750 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
751 			ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
752 			ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters);
753 		} else {
754 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
755 			ipv6_dev_mc_dec(dev, &in6addr_interfacelocal_allrouters);
756 			ipv6_dev_mc_dec(dev, &in6addr_sitelocal_allrouters);
757 		}
758 	}
759 
760 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
761 		if (ifa->flags&IFA_F_TENTATIVE)
762 			continue;
763 		if (idev->cnf.forwarding)
764 			addrconf_join_anycast(ifa);
765 		else
766 			addrconf_leave_anycast(ifa);
767 	}
768 	inet6_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
769 				     NETCONFA_FORWARDING,
770 				     dev->ifindex, &idev->cnf);
771 }
772 
773 
774 static void addrconf_forward_change(struct net *net, __s32 newf)
775 {
776 	struct net_device *dev;
777 	struct inet6_dev *idev;
778 
779 	for_each_netdev(net, dev) {
780 		idev = __in6_dev_get(dev);
781 		if (idev) {
782 			int changed = (!idev->cnf.forwarding) ^ (!newf);
783 			idev->cnf.forwarding = newf;
784 			if (changed)
785 				dev_forward_change(idev);
786 		}
787 	}
788 }
789 
790 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int newf)
791 {
792 	struct net *net;
793 	int old;
794 
795 	if (!rtnl_trylock())
796 		return restart_syscall();
797 
798 	net = (struct net *)table->extra2;
799 	old = *p;
800 	*p = newf;
801 
802 	if (p == &net->ipv6.devconf_dflt->forwarding) {
803 		if ((!newf) ^ (!old))
804 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
805 						     NETCONFA_FORWARDING,
806 						     NETCONFA_IFINDEX_DEFAULT,
807 						     net->ipv6.devconf_dflt);
808 		rtnl_unlock();
809 		return 0;
810 	}
811 
812 	if (p == &net->ipv6.devconf_all->forwarding) {
813 		int old_dflt = net->ipv6.devconf_dflt->forwarding;
814 
815 		net->ipv6.devconf_dflt->forwarding = newf;
816 		if ((!newf) ^ (!old_dflt))
817 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
818 						     NETCONFA_FORWARDING,
819 						     NETCONFA_IFINDEX_DEFAULT,
820 						     net->ipv6.devconf_dflt);
821 
822 		addrconf_forward_change(net, newf);
823 		if ((!newf) ^ (!old))
824 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
825 						     NETCONFA_FORWARDING,
826 						     NETCONFA_IFINDEX_ALL,
827 						     net->ipv6.devconf_all);
828 	} else if ((!newf) ^ (!old))
829 		dev_forward_change((struct inet6_dev *)table->extra1);
830 	rtnl_unlock();
831 
832 	if (newf)
833 		rt6_purge_dflt_routers(net);
834 	return 1;
835 }
836 
837 static void addrconf_linkdown_change(struct net *net, __s32 newf)
838 {
839 	struct net_device *dev;
840 	struct inet6_dev *idev;
841 
842 	for_each_netdev(net, dev) {
843 		idev = __in6_dev_get(dev);
844 		if (idev) {
845 			int changed = (!idev->cnf.ignore_routes_with_linkdown) ^ (!newf);
846 
847 			idev->cnf.ignore_routes_with_linkdown = newf;
848 			if (changed)
849 				inet6_netconf_notify_devconf(dev_net(dev),
850 							     RTM_NEWNETCONF,
851 							     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
852 							     dev->ifindex,
853 							     &idev->cnf);
854 		}
855 	}
856 }
857 
858 static int addrconf_fixup_linkdown(struct ctl_table *table, int *p, int newf)
859 {
860 	struct net *net;
861 	int old;
862 
863 	if (!rtnl_trylock())
864 		return restart_syscall();
865 
866 	net = (struct net *)table->extra2;
867 	old = *p;
868 	*p = newf;
869 
870 	if (p == &net->ipv6.devconf_dflt->ignore_routes_with_linkdown) {
871 		if ((!newf) ^ (!old))
872 			inet6_netconf_notify_devconf(net,
873 						     RTM_NEWNETCONF,
874 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
875 						     NETCONFA_IFINDEX_DEFAULT,
876 						     net->ipv6.devconf_dflt);
877 		rtnl_unlock();
878 		return 0;
879 	}
880 
881 	if (p == &net->ipv6.devconf_all->ignore_routes_with_linkdown) {
882 		net->ipv6.devconf_dflt->ignore_routes_with_linkdown = newf;
883 		addrconf_linkdown_change(net, newf);
884 		if ((!newf) ^ (!old))
885 			inet6_netconf_notify_devconf(net,
886 						     RTM_NEWNETCONF,
887 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
888 						     NETCONFA_IFINDEX_ALL,
889 						     net->ipv6.devconf_all);
890 	}
891 	rtnl_unlock();
892 
893 	return 1;
894 }
895 
896 #endif
897 
898 /* Nobody refers to this ifaddr, destroy it */
899 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
900 {
901 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
902 
903 #ifdef NET_REFCNT_DEBUG
904 	pr_debug("%s\n", __func__);
905 #endif
906 
907 	in6_dev_put(ifp->idev);
908 
909 	if (cancel_delayed_work(&ifp->dad_work))
910 		pr_notice("delayed DAD work was pending while freeing ifa=%p\n",
911 			  ifp);
912 
913 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
914 		pr_warn("Freeing alive inet6 address %p\n", ifp);
915 		return;
916 	}
917 
918 	kfree_rcu(ifp, rcu);
919 }
920 
921 static void
922 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
923 {
924 	struct list_head *p;
925 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
926 
927 	/*
928 	 * Each device address list is sorted in order of scope -
929 	 * global before linklocal.
930 	 */
931 	list_for_each(p, &idev->addr_list) {
932 		struct inet6_ifaddr *ifa
933 			= list_entry(p, struct inet6_ifaddr, if_list);
934 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
935 			break;
936 	}
937 
938 	list_add_tail_rcu(&ifp->if_list, p);
939 }
940 
941 static u32 inet6_addr_hash(const struct net *net, const struct in6_addr *addr)
942 {
943 	u32 val = ipv6_addr_hash(addr) ^ net_hash_mix(net);
944 
945 	return hash_32(val, IN6_ADDR_HSIZE_SHIFT);
946 }
947 
948 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
949 			       struct net_device *dev, unsigned int hash)
950 {
951 	struct inet6_ifaddr *ifp;
952 
953 	hlist_for_each_entry(ifp, &inet6_addr_lst[hash], addr_lst) {
954 		if (!net_eq(dev_net(ifp->idev->dev), net))
955 			continue;
956 		if (ipv6_addr_equal(&ifp->addr, addr)) {
957 			if (!dev || ifp->idev->dev == dev)
958 				return true;
959 		}
960 	}
961 	return false;
962 }
963 
964 static int ipv6_add_addr_hash(struct net_device *dev, struct inet6_ifaddr *ifa)
965 {
966 	unsigned int hash = inet6_addr_hash(dev_net(dev), &ifa->addr);
967 	int err = 0;
968 
969 	spin_lock(&addrconf_hash_lock);
970 
971 	/* Ignore adding duplicate addresses on an interface */
972 	if (ipv6_chk_same_addr(dev_net(dev), &ifa->addr, dev, hash)) {
973 		netdev_dbg(dev, "ipv6_add_addr: already assigned\n");
974 		err = -EEXIST;
975 	} else {
976 		hlist_add_head_rcu(&ifa->addr_lst, &inet6_addr_lst[hash]);
977 	}
978 
979 	spin_unlock(&addrconf_hash_lock);
980 
981 	return err;
982 }
983 
984 /* On success it returns ifp with increased reference count */
985 
986 static struct inet6_ifaddr *
987 ipv6_add_addr(struct inet6_dev *idev, struct ifa6_config *cfg,
988 	      bool can_block, struct netlink_ext_ack *extack)
989 {
990 	gfp_t gfp_flags = can_block ? GFP_KERNEL : GFP_ATOMIC;
991 	int addr_type = ipv6_addr_type(cfg->pfx);
992 	struct net *net = dev_net(idev->dev);
993 	struct inet6_ifaddr *ifa = NULL;
994 	struct fib6_info *f6i = NULL;
995 	int err = 0;
996 
997 	if (addr_type == IPV6_ADDR_ANY ||
998 	    addr_type & IPV6_ADDR_MULTICAST ||
999 	    (!(idev->dev->flags & IFF_LOOPBACK) &&
1000 	     addr_type & IPV6_ADDR_LOOPBACK))
1001 		return ERR_PTR(-EADDRNOTAVAIL);
1002 
1003 	if (idev->dead) {
1004 		err = -ENODEV;			/*XXX*/
1005 		goto out;
1006 	}
1007 
1008 	if (idev->cnf.disable_ipv6) {
1009 		err = -EACCES;
1010 		goto out;
1011 	}
1012 
1013 	/* validator notifier needs to be blocking;
1014 	 * do not call in atomic context
1015 	 */
1016 	if (can_block) {
1017 		struct in6_validator_info i6vi = {
1018 			.i6vi_addr = *cfg->pfx,
1019 			.i6vi_dev = idev,
1020 			.extack = extack,
1021 		};
1022 
1023 		err = inet6addr_validator_notifier_call_chain(NETDEV_UP, &i6vi);
1024 		err = notifier_to_errno(err);
1025 		if (err < 0)
1026 			goto out;
1027 	}
1028 
1029 	ifa = kzalloc(sizeof(*ifa), gfp_flags);
1030 	if (!ifa) {
1031 		err = -ENOBUFS;
1032 		goto out;
1033 	}
1034 
1035 	f6i = addrconf_f6i_alloc(net, idev, cfg->pfx, false, gfp_flags);
1036 	if (IS_ERR(f6i)) {
1037 		err = PTR_ERR(f6i);
1038 		f6i = NULL;
1039 		goto out;
1040 	}
1041 
1042 	if (net->ipv6.devconf_all->disable_policy ||
1043 	    idev->cnf.disable_policy)
1044 		f6i->dst_nopolicy = true;
1045 
1046 	neigh_parms_data_state_setall(idev->nd_parms);
1047 
1048 	ifa->addr = *cfg->pfx;
1049 	if (cfg->peer_pfx)
1050 		ifa->peer_addr = *cfg->peer_pfx;
1051 
1052 	spin_lock_init(&ifa->lock);
1053 	INIT_DELAYED_WORK(&ifa->dad_work, addrconf_dad_work);
1054 	INIT_HLIST_NODE(&ifa->addr_lst);
1055 	ifa->scope = cfg->scope;
1056 	ifa->prefix_len = cfg->plen;
1057 	ifa->rt_priority = cfg->rt_priority;
1058 	ifa->flags = cfg->ifa_flags;
1059 	/* No need to add the TENTATIVE flag for addresses with NODAD */
1060 	if (!(cfg->ifa_flags & IFA_F_NODAD))
1061 		ifa->flags |= IFA_F_TENTATIVE;
1062 	ifa->valid_lft = cfg->valid_lft;
1063 	ifa->prefered_lft = cfg->preferred_lft;
1064 	ifa->cstamp = ifa->tstamp = jiffies;
1065 	ifa->tokenized = false;
1066 
1067 	ifa->rt = f6i;
1068 
1069 	ifa->idev = idev;
1070 	in6_dev_hold(idev);
1071 
1072 	/* For caller */
1073 	refcount_set(&ifa->refcnt, 1);
1074 
1075 	rcu_read_lock_bh();
1076 
1077 	err = ipv6_add_addr_hash(idev->dev, ifa);
1078 	if (err < 0) {
1079 		rcu_read_unlock_bh();
1080 		goto out;
1081 	}
1082 
1083 	write_lock(&idev->lock);
1084 
1085 	/* Add to inet6_dev unicast addr list. */
1086 	ipv6_link_dev_addr(idev, ifa);
1087 
1088 	if (ifa->flags&IFA_F_TEMPORARY) {
1089 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
1090 		in6_ifa_hold(ifa);
1091 	}
1092 
1093 	in6_ifa_hold(ifa);
1094 	write_unlock(&idev->lock);
1095 
1096 	rcu_read_unlock_bh();
1097 
1098 	inet6addr_notifier_call_chain(NETDEV_UP, ifa);
1099 out:
1100 	if (unlikely(err < 0)) {
1101 		fib6_info_release(f6i);
1102 
1103 		if (ifa) {
1104 			if (ifa->idev)
1105 				in6_dev_put(ifa->idev);
1106 			kfree(ifa);
1107 		}
1108 		ifa = ERR_PTR(err);
1109 	}
1110 
1111 	return ifa;
1112 }
1113 
1114 enum cleanup_prefix_rt_t {
1115 	CLEANUP_PREFIX_RT_NOP,    /* no cleanup action for prefix route */
1116 	CLEANUP_PREFIX_RT_DEL,    /* delete the prefix route */
1117 	CLEANUP_PREFIX_RT_EXPIRE, /* update the lifetime of the prefix route */
1118 };
1119 
1120 /*
1121  * Check, whether the prefix for ifp would still need a prefix route
1122  * after deleting ifp. The function returns one of the CLEANUP_PREFIX_RT_*
1123  * constants.
1124  *
1125  * 1) we don't purge prefix if address was not permanent.
1126  *    prefix is managed by its own lifetime.
1127  * 2) we also don't purge, if the address was IFA_F_NOPREFIXROUTE.
1128  * 3) if there are no addresses, delete prefix.
1129  * 4) if there are still other permanent address(es),
1130  *    corresponding prefix is still permanent.
1131  * 5) if there are still other addresses with IFA_F_NOPREFIXROUTE,
1132  *    don't purge the prefix, assume user space is managing it.
1133  * 6) otherwise, update prefix lifetime to the
1134  *    longest valid lifetime among the corresponding
1135  *    addresses on the device.
1136  *    Note: subsequent RA will update lifetime.
1137  **/
1138 static enum cleanup_prefix_rt_t
1139 check_cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long *expires)
1140 {
1141 	struct inet6_ifaddr *ifa;
1142 	struct inet6_dev *idev = ifp->idev;
1143 	unsigned long lifetime;
1144 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_DEL;
1145 
1146 	*expires = jiffies;
1147 
1148 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
1149 		if (ifa == ifp)
1150 			continue;
1151 		if (!ipv6_prefix_equal(&ifa->addr, &ifp->addr,
1152 				       ifp->prefix_len))
1153 			continue;
1154 		if (ifa->flags & (IFA_F_PERMANENT | IFA_F_NOPREFIXROUTE))
1155 			return CLEANUP_PREFIX_RT_NOP;
1156 
1157 		action = CLEANUP_PREFIX_RT_EXPIRE;
1158 
1159 		spin_lock(&ifa->lock);
1160 
1161 		lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
1162 		/*
1163 		 * Note: Because this address is
1164 		 * not permanent, lifetime <
1165 		 * LONG_MAX / HZ here.
1166 		 */
1167 		if (time_before(*expires, ifa->tstamp + lifetime * HZ))
1168 			*expires = ifa->tstamp + lifetime * HZ;
1169 		spin_unlock(&ifa->lock);
1170 	}
1171 
1172 	return action;
1173 }
1174 
1175 static void
1176 cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long expires, bool del_rt)
1177 {
1178 	struct fib6_info *f6i;
1179 
1180 	f6i = addrconf_get_prefix_route(&ifp->addr,
1181 				       ifp->prefix_len,
1182 				       ifp->idev->dev,
1183 				       0, RTF_GATEWAY | RTF_DEFAULT);
1184 	if (f6i) {
1185 		if (del_rt)
1186 			ip6_del_rt(dev_net(ifp->idev->dev), f6i);
1187 		else {
1188 			if (!(f6i->fib6_flags & RTF_EXPIRES))
1189 				fib6_set_expires(f6i, expires);
1190 			fib6_info_release(f6i);
1191 		}
1192 	}
1193 }
1194 
1195 
1196 /* This function wants to get referenced ifp and releases it before return */
1197 
1198 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
1199 {
1200 	int state;
1201 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_NOP;
1202 	unsigned long expires;
1203 
1204 	ASSERT_RTNL();
1205 
1206 	spin_lock_bh(&ifp->lock);
1207 	state = ifp->state;
1208 	ifp->state = INET6_IFADDR_STATE_DEAD;
1209 	spin_unlock_bh(&ifp->lock);
1210 
1211 	if (state == INET6_IFADDR_STATE_DEAD)
1212 		goto out;
1213 
1214 	spin_lock_bh(&addrconf_hash_lock);
1215 	hlist_del_init_rcu(&ifp->addr_lst);
1216 	spin_unlock_bh(&addrconf_hash_lock);
1217 
1218 	write_lock_bh(&ifp->idev->lock);
1219 
1220 	if (ifp->flags&IFA_F_TEMPORARY) {
1221 		list_del(&ifp->tmp_list);
1222 		if (ifp->ifpub) {
1223 			in6_ifa_put(ifp->ifpub);
1224 			ifp->ifpub = NULL;
1225 		}
1226 		__in6_ifa_put(ifp);
1227 	}
1228 
1229 	if (ifp->flags & IFA_F_PERMANENT && !(ifp->flags & IFA_F_NOPREFIXROUTE))
1230 		action = check_cleanup_prefix_route(ifp, &expires);
1231 
1232 	list_del_rcu(&ifp->if_list);
1233 	__in6_ifa_put(ifp);
1234 
1235 	write_unlock_bh(&ifp->idev->lock);
1236 
1237 	addrconf_del_dad_work(ifp);
1238 
1239 	ipv6_ifa_notify(RTM_DELADDR, ifp);
1240 
1241 	inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);
1242 
1243 	if (action != CLEANUP_PREFIX_RT_NOP) {
1244 		cleanup_prefix_route(ifp, expires,
1245 			action == CLEANUP_PREFIX_RT_DEL);
1246 	}
1247 
1248 	/* clean up prefsrc entries */
1249 	rt6_remove_prefsrc(ifp);
1250 out:
1251 	in6_ifa_put(ifp);
1252 }
1253 
1254 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp,
1255 				struct inet6_ifaddr *ift,
1256 				bool block)
1257 {
1258 	struct inet6_dev *idev = ifp->idev;
1259 	struct in6_addr addr, *tmpaddr;
1260 	unsigned long tmp_tstamp, age;
1261 	unsigned long regen_advance;
1262 	struct ifa6_config cfg;
1263 	int ret = 0;
1264 	unsigned long now = jiffies;
1265 	long max_desync_factor;
1266 	s32 cnf_temp_preferred_lft;
1267 
1268 	write_lock_bh(&idev->lock);
1269 	if (ift) {
1270 		spin_lock_bh(&ift->lock);
1271 		memcpy(&addr.s6_addr[8], &ift->addr.s6_addr[8], 8);
1272 		spin_unlock_bh(&ift->lock);
1273 		tmpaddr = &addr;
1274 	} else {
1275 		tmpaddr = NULL;
1276 	}
1277 retry:
1278 	in6_dev_hold(idev);
1279 	if (idev->cnf.use_tempaddr <= 0) {
1280 		write_unlock_bh(&idev->lock);
1281 		pr_info("%s: use_tempaddr is disabled\n", __func__);
1282 		in6_dev_put(idev);
1283 		ret = -1;
1284 		goto out;
1285 	}
1286 	spin_lock_bh(&ifp->lock);
1287 	if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
1288 		idev->cnf.use_tempaddr = -1;	/*XXX*/
1289 		spin_unlock_bh(&ifp->lock);
1290 		write_unlock_bh(&idev->lock);
1291 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1292 			__func__);
1293 		in6_dev_put(idev);
1294 		ret = -1;
1295 		goto out;
1296 	}
1297 	in6_ifa_hold(ifp);
1298 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1299 	ipv6_try_regen_rndid(idev, tmpaddr);
1300 	memcpy(&addr.s6_addr[8], idev->rndid, 8);
1301 	age = (now - ifp->tstamp) / HZ;
1302 
1303 	regen_advance = idev->cnf.regen_max_retry *
1304 			idev->cnf.dad_transmits *
1305 			NEIGH_VAR(idev->nd_parms, RETRANS_TIME) / HZ;
1306 
1307 	/* recalculate max_desync_factor each time and update
1308 	 * idev->desync_factor if it's larger
1309 	 */
1310 	cnf_temp_preferred_lft = READ_ONCE(idev->cnf.temp_prefered_lft);
1311 	max_desync_factor = min_t(__u32,
1312 				  idev->cnf.max_desync_factor,
1313 				  cnf_temp_preferred_lft - regen_advance);
1314 
1315 	if (unlikely(idev->desync_factor > max_desync_factor)) {
1316 		if (max_desync_factor > 0) {
1317 			get_random_bytes(&idev->desync_factor,
1318 					 sizeof(idev->desync_factor));
1319 			idev->desync_factor %= max_desync_factor;
1320 		} else {
1321 			idev->desync_factor = 0;
1322 		}
1323 	}
1324 
1325 	memset(&cfg, 0, sizeof(cfg));
1326 	cfg.valid_lft = min_t(__u32, ifp->valid_lft,
1327 			      idev->cnf.temp_valid_lft + age);
1328 	cfg.preferred_lft = cnf_temp_preferred_lft + age - idev->desync_factor;
1329 	cfg.preferred_lft = min_t(__u32, ifp->prefered_lft, cfg.preferred_lft);
1330 
1331 	cfg.plen = ifp->prefix_len;
1332 	tmp_tstamp = ifp->tstamp;
1333 	spin_unlock_bh(&ifp->lock);
1334 
1335 	write_unlock_bh(&idev->lock);
1336 
1337 	/* A temporary address is created only if this calculated Preferred
1338 	 * Lifetime is greater than REGEN_ADVANCE time units.  In particular,
1339 	 * an implementation must not create a temporary address with a zero
1340 	 * Preferred Lifetime.
1341 	 * Use age calculation as in addrconf_verify to avoid unnecessary
1342 	 * temporary addresses being generated.
1343 	 */
1344 	age = (now - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
1345 	if (cfg.preferred_lft <= regen_advance + age) {
1346 		in6_ifa_put(ifp);
1347 		in6_dev_put(idev);
1348 		ret = -1;
1349 		goto out;
1350 	}
1351 
1352 	cfg.ifa_flags = IFA_F_TEMPORARY;
1353 	/* set in addrconf_prefix_rcv() */
1354 	if (ifp->flags & IFA_F_OPTIMISTIC)
1355 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
1356 
1357 	cfg.pfx = &addr;
1358 	cfg.scope = ipv6_addr_scope(cfg.pfx);
1359 
1360 	ift = ipv6_add_addr(idev, &cfg, block, NULL);
1361 	if (IS_ERR(ift)) {
1362 		in6_ifa_put(ifp);
1363 		in6_dev_put(idev);
1364 		pr_info("%s: retry temporary address regeneration\n", __func__);
1365 		tmpaddr = &addr;
1366 		write_lock_bh(&idev->lock);
1367 		goto retry;
1368 	}
1369 
1370 	spin_lock_bh(&ift->lock);
1371 	ift->ifpub = ifp;
1372 	ift->cstamp = now;
1373 	ift->tstamp = tmp_tstamp;
1374 	spin_unlock_bh(&ift->lock);
1375 
1376 	addrconf_dad_start(ift);
1377 	in6_ifa_put(ift);
1378 	in6_dev_put(idev);
1379 out:
1380 	return ret;
1381 }
1382 
1383 /*
1384  *	Choose an appropriate source address (RFC3484)
1385  */
1386 enum {
1387 	IPV6_SADDR_RULE_INIT = 0,
1388 	IPV6_SADDR_RULE_LOCAL,
1389 	IPV6_SADDR_RULE_SCOPE,
1390 	IPV6_SADDR_RULE_PREFERRED,
1391 #ifdef CONFIG_IPV6_MIP6
1392 	IPV6_SADDR_RULE_HOA,
1393 #endif
1394 	IPV6_SADDR_RULE_OIF,
1395 	IPV6_SADDR_RULE_LABEL,
1396 	IPV6_SADDR_RULE_PRIVACY,
1397 	IPV6_SADDR_RULE_ORCHID,
1398 	IPV6_SADDR_RULE_PREFIX,
1399 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1400 	IPV6_SADDR_RULE_NOT_OPTIMISTIC,
1401 #endif
1402 	IPV6_SADDR_RULE_MAX
1403 };
1404 
1405 struct ipv6_saddr_score {
1406 	int			rule;
1407 	int			addr_type;
1408 	struct inet6_ifaddr	*ifa;
1409 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1410 	int			scopedist;
1411 	int			matchlen;
1412 };
1413 
1414 struct ipv6_saddr_dst {
1415 	const struct in6_addr *addr;
1416 	int ifindex;
1417 	int scope;
1418 	int label;
1419 	unsigned int prefs;
1420 };
1421 
1422 static inline int ipv6_saddr_preferred(int type)
1423 {
1424 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1425 		return 1;
1426 	return 0;
1427 }
1428 
1429 static bool ipv6_use_optimistic_addr(struct net *net,
1430 				     struct inet6_dev *idev)
1431 {
1432 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1433 	if (!idev)
1434 		return false;
1435 	if (!net->ipv6.devconf_all->optimistic_dad && !idev->cnf.optimistic_dad)
1436 		return false;
1437 	if (!net->ipv6.devconf_all->use_optimistic && !idev->cnf.use_optimistic)
1438 		return false;
1439 
1440 	return true;
1441 #else
1442 	return false;
1443 #endif
1444 }
1445 
1446 static bool ipv6_allow_optimistic_dad(struct net *net,
1447 				      struct inet6_dev *idev)
1448 {
1449 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1450 	if (!idev)
1451 		return false;
1452 	if (!net->ipv6.devconf_all->optimistic_dad && !idev->cnf.optimistic_dad)
1453 		return false;
1454 
1455 	return true;
1456 #else
1457 	return false;
1458 #endif
1459 }
1460 
1461 static int ipv6_get_saddr_eval(struct net *net,
1462 			       struct ipv6_saddr_score *score,
1463 			       struct ipv6_saddr_dst *dst,
1464 			       int i)
1465 {
1466 	int ret;
1467 
1468 	if (i <= score->rule) {
1469 		switch (i) {
1470 		case IPV6_SADDR_RULE_SCOPE:
1471 			ret = score->scopedist;
1472 			break;
1473 		case IPV6_SADDR_RULE_PREFIX:
1474 			ret = score->matchlen;
1475 			break;
1476 		default:
1477 			ret = !!test_bit(i, score->scorebits);
1478 		}
1479 		goto out;
1480 	}
1481 
1482 	switch (i) {
1483 	case IPV6_SADDR_RULE_INIT:
1484 		/* Rule 0: remember if hiscore is not ready yet */
1485 		ret = !!score->ifa;
1486 		break;
1487 	case IPV6_SADDR_RULE_LOCAL:
1488 		/* Rule 1: Prefer same address */
1489 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1490 		break;
1491 	case IPV6_SADDR_RULE_SCOPE:
1492 		/* Rule 2: Prefer appropriate scope
1493 		 *
1494 		 *      ret
1495 		 *       ^
1496 		 *    -1 |  d 15
1497 		 *    ---+--+-+---> scope
1498 		 *       |
1499 		 *       |             d is scope of the destination.
1500 		 *  B-d  |  \
1501 		 *       |   \      <- smaller scope is better if
1502 		 *  B-15 |    \        if scope is enough for destination.
1503 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1504 		 * d-C-1 | /
1505 		 *       |/         <- greater is better
1506 		 *   -C  /             if scope is not enough for destination.
1507 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1508 		 *
1509 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1510 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1511 		 * Assume B = 0 and we get C > 29.
1512 		 */
1513 		ret = __ipv6_addr_src_scope(score->addr_type);
1514 		if (ret >= dst->scope)
1515 			ret = -ret;
1516 		else
1517 			ret -= 128;	/* 30 is enough */
1518 		score->scopedist = ret;
1519 		break;
1520 	case IPV6_SADDR_RULE_PREFERRED:
1521 	    {
1522 		/* Rule 3: Avoid deprecated and optimistic addresses */
1523 		u8 avoid = IFA_F_DEPRECATED;
1524 
1525 		if (!ipv6_use_optimistic_addr(net, score->ifa->idev))
1526 			avoid |= IFA_F_OPTIMISTIC;
1527 		ret = ipv6_saddr_preferred(score->addr_type) ||
1528 		      !(score->ifa->flags & avoid);
1529 		break;
1530 	    }
1531 #ifdef CONFIG_IPV6_MIP6
1532 	case IPV6_SADDR_RULE_HOA:
1533 	    {
1534 		/* Rule 4: Prefer home address */
1535 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1536 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1537 		break;
1538 	    }
1539 #endif
1540 	case IPV6_SADDR_RULE_OIF:
1541 		/* Rule 5: Prefer outgoing interface */
1542 		ret = (!dst->ifindex ||
1543 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1544 		break;
1545 	case IPV6_SADDR_RULE_LABEL:
1546 		/* Rule 6: Prefer matching label */
1547 		ret = ipv6_addr_label(net,
1548 				      &score->ifa->addr, score->addr_type,
1549 				      score->ifa->idev->dev->ifindex) == dst->label;
1550 		break;
1551 	case IPV6_SADDR_RULE_PRIVACY:
1552 	    {
1553 		/* Rule 7: Prefer public address
1554 		 * Note: prefer temporary address if use_tempaddr >= 2
1555 		 */
1556 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1557 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1558 				score->ifa->idev->cnf.use_tempaddr >= 2;
1559 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1560 		break;
1561 	    }
1562 	case IPV6_SADDR_RULE_ORCHID:
1563 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1564 		 *	    non-ORCHID vs non-ORCHID
1565 		 */
1566 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1567 			ipv6_addr_orchid(dst->addr));
1568 		break;
1569 	case IPV6_SADDR_RULE_PREFIX:
1570 		/* Rule 8: Use longest matching prefix */
1571 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1572 		if (ret > score->ifa->prefix_len)
1573 			ret = score->ifa->prefix_len;
1574 		score->matchlen = ret;
1575 		break;
1576 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1577 	case IPV6_SADDR_RULE_NOT_OPTIMISTIC:
1578 		/* Optimistic addresses still have lower precedence than other
1579 		 * preferred addresses.
1580 		 */
1581 		ret = !(score->ifa->flags & IFA_F_OPTIMISTIC);
1582 		break;
1583 #endif
1584 	default:
1585 		ret = 0;
1586 	}
1587 
1588 	if (ret)
1589 		__set_bit(i, score->scorebits);
1590 	score->rule = i;
1591 out:
1592 	return ret;
1593 }
1594 
1595 static int __ipv6_dev_get_saddr(struct net *net,
1596 				struct ipv6_saddr_dst *dst,
1597 				struct inet6_dev *idev,
1598 				struct ipv6_saddr_score *scores,
1599 				int hiscore_idx)
1600 {
1601 	struct ipv6_saddr_score *score = &scores[1 - hiscore_idx], *hiscore = &scores[hiscore_idx];
1602 
1603 	list_for_each_entry_rcu(score->ifa, &idev->addr_list, if_list) {
1604 		int i;
1605 
1606 		/*
1607 		 * - Tentative Address (RFC2462 section 5.4)
1608 		 *  - A tentative address is not considered
1609 		 *    "assigned to an interface" in the traditional
1610 		 *    sense, unless it is also flagged as optimistic.
1611 		 * - Candidate Source Address (section 4)
1612 		 *  - In any case, anycast addresses, multicast
1613 		 *    addresses, and the unspecified address MUST
1614 		 *    NOT be included in a candidate set.
1615 		 */
1616 		if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1617 		    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1618 			continue;
1619 
1620 		score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1621 
1622 		if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1623 			     score->addr_type & IPV6_ADDR_MULTICAST)) {
1624 			net_dbg_ratelimited("ADDRCONF: unspecified / multicast address assigned as unicast address on %s",
1625 					    idev->dev->name);
1626 			continue;
1627 		}
1628 
1629 		score->rule = -1;
1630 		bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1631 
1632 		for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1633 			int minihiscore, miniscore;
1634 
1635 			minihiscore = ipv6_get_saddr_eval(net, hiscore, dst, i);
1636 			miniscore = ipv6_get_saddr_eval(net, score, dst, i);
1637 
1638 			if (minihiscore > miniscore) {
1639 				if (i == IPV6_SADDR_RULE_SCOPE &&
1640 				    score->scopedist > 0) {
1641 					/*
1642 					 * special case:
1643 					 * each remaining entry
1644 					 * has too small (not enough)
1645 					 * scope, because ifa entries
1646 					 * are sorted by their scope
1647 					 * values.
1648 					 */
1649 					goto out;
1650 				}
1651 				break;
1652 			} else if (minihiscore < miniscore) {
1653 				swap(hiscore, score);
1654 				hiscore_idx = 1 - hiscore_idx;
1655 
1656 				/* restore our iterator */
1657 				score->ifa = hiscore->ifa;
1658 
1659 				break;
1660 			}
1661 		}
1662 	}
1663 out:
1664 	return hiscore_idx;
1665 }
1666 
1667 static int ipv6_get_saddr_master(struct net *net,
1668 				 const struct net_device *dst_dev,
1669 				 const struct net_device *master,
1670 				 struct ipv6_saddr_dst *dst,
1671 				 struct ipv6_saddr_score *scores,
1672 				 int hiscore_idx)
1673 {
1674 	struct inet6_dev *idev;
1675 
1676 	idev = __in6_dev_get(dst_dev);
1677 	if (idev)
1678 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1679 						   scores, hiscore_idx);
1680 
1681 	idev = __in6_dev_get(master);
1682 	if (idev)
1683 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1684 						   scores, hiscore_idx);
1685 
1686 	return hiscore_idx;
1687 }
1688 
1689 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1690 		       const struct in6_addr *daddr, unsigned int prefs,
1691 		       struct in6_addr *saddr)
1692 {
1693 	struct ipv6_saddr_score scores[2], *hiscore;
1694 	struct ipv6_saddr_dst dst;
1695 	struct inet6_dev *idev;
1696 	struct net_device *dev;
1697 	int dst_type;
1698 	bool use_oif_addr = false;
1699 	int hiscore_idx = 0;
1700 	int ret = 0;
1701 
1702 	dst_type = __ipv6_addr_type(daddr);
1703 	dst.addr = daddr;
1704 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1705 	dst.scope = __ipv6_addr_src_scope(dst_type);
1706 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1707 	dst.prefs = prefs;
1708 
1709 	scores[hiscore_idx].rule = -1;
1710 	scores[hiscore_idx].ifa = NULL;
1711 
1712 	rcu_read_lock();
1713 
1714 	/* Candidate Source Address (section 4)
1715 	 *  - multicast and link-local destination address,
1716 	 *    the set of candidate source address MUST only
1717 	 *    include addresses assigned to interfaces
1718 	 *    belonging to the same link as the outgoing
1719 	 *    interface.
1720 	 * (- For site-local destination addresses, the
1721 	 *    set of candidate source addresses MUST only
1722 	 *    include addresses assigned to interfaces
1723 	 *    belonging to the same site as the outgoing
1724 	 *    interface.)
1725 	 *  - "It is RECOMMENDED that the candidate source addresses
1726 	 *    be the set of unicast addresses assigned to the
1727 	 *    interface that will be used to send to the destination
1728 	 *    (the 'outgoing' interface)." (RFC 6724)
1729 	 */
1730 	if (dst_dev) {
1731 		idev = __in6_dev_get(dst_dev);
1732 		if ((dst_type & IPV6_ADDR_MULTICAST) ||
1733 		    dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL ||
1734 		    (idev && idev->cnf.use_oif_addrs_only)) {
1735 			use_oif_addr = true;
1736 		}
1737 	}
1738 
1739 	if (use_oif_addr) {
1740 		if (idev)
1741 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1742 	} else {
1743 		const struct net_device *master;
1744 		int master_idx = 0;
1745 
1746 		/* if dst_dev exists and is enslaved to an L3 device, then
1747 		 * prefer addresses from dst_dev and then the master over
1748 		 * any other enslaved devices in the L3 domain.
1749 		 */
1750 		master = l3mdev_master_dev_rcu(dst_dev);
1751 		if (master) {
1752 			master_idx = master->ifindex;
1753 
1754 			hiscore_idx = ipv6_get_saddr_master(net, dst_dev,
1755 							    master, &dst,
1756 							    scores, hiscore_idx);
1757 
1758 			if (scores[hiscore_idx].ifa)
1759 				goto out;
1760 		}
1761 
1762 		for_each_netdev_rcu(net, dev) {
1763 			/* only consider addresses on devices in the
1764 			 * same L3 domain
1765 			 */
1766 			if (l3mdev_master_ifindex_rcu(dev) != master_idx)
1767 				continue;
1768 			idev = __in6_dev_get(dev);
1769 			if (!idev)
1770 				continue;
1771 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1772 		}
1773 	}
1774 
1775 out:
1776 	hiscore = &scores[hiscore_idx];
1777 	if (!hiscore->ifa)
1778 		ret = -EADDRNOTAVAIL;
1779 	else
1780 		*saddr = hiscore->ifa->addr;
1781 
1782 	rcu_read_unlock();
1783 	return ret;
1784 }
1785 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1786 
1787 int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr,
1788 		      u32 banned_flags)
1789 {
1790 	struct inet6_ifaddr *ifp;
1791 	int err = -EADDRNOTAVAIL;
1792 
1793 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1794 		if (ifp->scope > IFA_LINK)
1795 			break;
1796 		if (ifp->scope == IFA_LINK &&
1797 		    !(ifp->flags & banned_flags)) {
1798 			*addr = ifp->addr;
1799 			err = 0;
1800 			break;
1801 		}
1802 	}
1803 	return err;
1804 }
1805 
1806 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1807 		    u32 banned_flags)
1808 {
1809 	struct inet6_dev *idev;
1810 	int err = -EADDRNOTAVAIL;
1811 
1812 	rcu_read_lock();
1813 	idev = __in6_dev_get(dev);
1814 	if (idev) {
1815 		read_lock_bh(&idev->lock);
1816 		err = __ipv6_get_lladdr(idev, addr, banned_flags);
1817 		read_unlock_bh(&idev->lock);
1818 	}
1819 	rcu_read_unlock();
1820 	return err;
1821 }
1822 
1823 static int ipv6_count_addresses(const struct inet6_dev *idev)
1824 {
1825 	const struct inet6_ifaddr *ifp;
1826 	int cnt = 0;
1827 
1828 	rcu_read_lock();
1829 	list_for_each_entry_rcu(ifp, &idev->addr_list, if_list)
1830 		cnt++;
1831 	rcu_read_unlock();
1832 	return cnt;
1833 }
1834 
1835 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1836 		  const struct net_device *dev, int strict)
1837 {
1838 	return ipv6_chk_addr_and_flags(net, addr, dev, !dev,
1839 				       strict, IFA_F_TENTATIVE);
1840 }
1841 EXPORT_SYMBOL(ipv6_chk_addr);
1842 
1843 /* device argument is used to find the L3 domain of interest. If
1844  * skip_dev_check is set, then the ifp device is not checked against
1845  * the passed in dev argument. So the 2 cases for addresses checks are:
1846  *   1. does the address exist in the L3 domain that dev is part of
1847  *      (skip_dev_check = true), or
1848  *
1849  *   2. does the address exist on the specific device
1850  *      (skip_dev_check = false)
1851  */
1852 int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
1853 			    const struct net_device *dev, bool skip_dev_check,
1854 			    int strict, u32 banned_flags)
1855 {
1856 	unsigned int hash = inet6_addr_hash(net, addr);
1857 	const struct net_device *l3mdev;
1858 	struct inet6_ifaddr *ifp;
1859 	u32 ifp_flags;
1860 
1861 	rcu_read_lock();
1862 
1863 	l3mdev = l3mdev_master_dev_rcu(dev);
1864 	if (skip_dev_check)
1865 		dev = NULL;
1866 
1867 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
1868 		if (!net_eq(dev_net(ifp->idev->dev), net))
1869 			continue;
1870 
1871 		if (l3mdev_master_dev_rcu(ifp->idev->dev) != l3mdev)
1872 			continue;
1873 
1874 		/* Decouple optimistic from tentative for evaluation here.
1875 		 * Ban optimistic addresses explicitly, when required.
1876 		 */
1877 		ifp_flags = (ifp->flags&IFA_F_OPTIMISTIC)
1878 			    ? (ifp->flags&~IFA_F_TENTATIVE)
1879 			    : ifp->flags;
1880 		if (ipv6_addr_equal(&ifp->addr, addr) &&
1881 		    !(ifp_flags&banned_flags) &&
1882 		    (!dev || ifp->idev->dev == dev ||
1883 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1884 			rcu_read_unlock();
1885 			return 1;
1886 		}
1887 	}
1888 
1889 	rcu_read_unlock();
1890 	return 0;
1891 }
1892 EXPORT_SYMBOL(ipv6_chk_addr_and_flags);
1893 
1894 
1895 /* Compares an address/prefix_len with addresses on device @dev.
1896  * If one is found it returns true.
1897  */
1898 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
1899 	const unsigned int prefix_len, struct net_device *dev)
1900 {
1901 	const struct inet6_ifaddr *ifa;
1902 	const struct inet6_dev *idev;
1903 	bool ret = false;
1904 
1905 	rcu_read_lock();
1906 	idev = __in6_dev_get(dev);
1907 	if (idev) {
1908 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
1909 			ret = ipv6_prefix_equal(addr, &ifa->addr, prefix_len);
1910 			if (ret)
1911 				break;
1912 		}
1913 	}
1914 	rcu_read_unlock();
1915 
1916 	return ret;
1917 }
1918 EXPORT_SYMBOL(ipv6_chk_custom_prefix);
1919 
1920 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
1921 {
1922 	const struct inet6_ifaddr *ifa;
1923 	const struct inet6_dev *idev;
1924 	int	onlink;
1925 
1926 	onlink = 0;
1927 	rcu_read_lock();
1928 	idev = __in6_dev_get(dev);
1929 	if (idev) {
1930 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
1931 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
1932 						   ifa->prefix_len);
1933 			if (onlink)
1934 				break;
1935 		}
1936 	}
1937 	rcu_read_unlock();
1938 	return onlink;
1939 }
1940 EXPORT_SYMBOL(ipv6_chk_prefix);
1941 
1942 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
1943 				     struct net_device *dev, int strict)
1944 {
1945 	unsigned int hash = inet6_addr_hash(net, addr);
1946 	struct inet6_ifaddr *ifp, *result = NULL;
1947 
1948 	rcu_read_lock();
1949 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
1950 		if (!net_eq(dev_net(ifp->idev->dev), net))
1951 			continue;
1952 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1953 			if (!dev || ifp->idev->dev == dev ||
1954 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
1955 				result = ifp;
1956 				in6_ifa_hold(ifp);
1957 				break;
1958 			}
1959 		}
1960 	}
1961 	rcu_read_unlock();
1962 
1963 	return result;
1964 }
1965 
1966 /* Gets referenced address, destroys ifaddr */
1967 
1968 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
1969 {
1970 	if (dad_failed)
1971 		ifp->flags |= IFA_F_DADFAILED;
1972 
1973 	if (ifp->flags&IFA_F_TEMPORARY) {
1974 		struct inet6_ifaddr *ifpub;
1975 		spin_lock_bh(&ifp->lock);
1976 		ifpub = ifp->ifpub;
1977 		if (ifpub) {
1978 			in6_ifa_hold(ifpub);
1979 			spin_unlock_bh(&ifp->lock);
1980 			ipv6_create_tempaddr(ifpub, ifp, true);
1981 			in6_ifa_put(ifpub);
1982 		} else {
1983 			spin_unlock_bh(&ifp->lock);
1984 		}
1985 		ipv6_del_addr(ifp);
1986 	} else if (ifp->flags&IFA_F_PERMANENT || !dad_failed) {
1987 		spin_lock_bh(&ifp->lock);
1988 		addrconf_del_dad_work(ifp);
1989 		ifp->flags |= IFA_F_TENTATIVE;
1990 		if (dad_failed)
1991 			ifp->flags &= ~IFA_F_OPTIMISTIC;
1992 		spin_unlock_bh(&ifp->lock);
1993 		if (dad_failed)
1994 			ipv6_ifa_notify(0, ifp);
1995 		in6_ifa_put(ifp);
1996 	} else {
1997 		ipv6_del_addr(ifp);
1998 	}
1999 }
2000 
2001 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
2002 {
2003 	int err = -ENOENT;
2004 
2005 	spin_lock_bh(&ifp->lock);
2006 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
2007 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
2008 		err = 0;
2009 	}
2010 	spin_unlock_bh(&ifp->lock);
2011 
2012 	return err;
2013 }
2014 
2015 void addrconf_dad_failure(struct sk_buff *skb, struct inet6_ifaddr *ifp)
2016 {
2017 	struct inet6_dev *idev = ifp->idev;
2018 	struct net *net = dev_net(ifp->idev->dev);
2019 
2020 	if (addrconf_dad_end(ifp)) {
2021 		in6_ifa_put(ifp);
2022 		return;
2023 	}
2024 
2025 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c used by %pM detected!\n",
2026 			     ifp->idev->dev->name, &ifp->addr, eth_hdr(skb)->h_source);
2027 
2028 	spin_lock_bh(&ifp->lock);
2029 
2030 	if (ifp->flags & IFA_F_STABLE_PRIVACY) {
2031 		struct in6_addr new_addr;
2032 		struct inet6_ifaddr *ifp2;
2033 		int retries = ifp->stable_privacy_retry + 1;
2034 		struct ifa6_config cfg = {
2035 			.pfx = &new_addr,
2036 			.plen = ifp->prefix_len,
2037 			.ifa_flags = ifp->flags,
2038 			.valid_lft = ifp->valid_lft,
2039 			.preferred_lft = ifp->prefered_lft,
2040 			.scope = ifp->scope,
2041 		};
2042 
2043 		if (retries > net->ipv6.sysctl.idgen_retries) {
2044 			net_info_ratelimited("%s: privacy stable address generation failed because of DAD conflicts!\n",
2045 					     ifp->idev->dev->name);
2046 			goto errdad;
2047 		}
2048 
2049 		new_addr = ifp->addr;
2050 		if (ipv6_generate_stable_address(&new_addr, retries,
2051 						 idev))
2052 			goto errdad;
2053 
2054 		spin_unlock_bh(&ifp->lock);
2055 
2056 		if (idev->cnf.max_addresses &&
2057 		    ipv6_count_addresses(idev) >=
2058 		    idev->cnf.max_addresses)
2059 			goto lock_errdad;
2060 
2061 		net_info_ratelimited("%s: generating new stable privacy address because of DAD conflict\n",
2062 				     ifp->idev->dev->name);
2063 
2064 		ifp2 = ipv6_add_addr(idev, &cfg, false, NULL);
2065 		if (IS_ERR(ifp2))
2066 			goto lock_errdad;
2067 
2068 		spin_lock_bh(&ifp2->lock);
2069 		ifp2->stable_privacy_retry = retries;
2070 		ifp2->state = INET6_IFADDR_STATE_PREDAD;
2071 		spin_unlock_bh(&ifp2->lock);
2072 
2073 		addrconf_mod_dad_work(ifp2, net->ipv6.sysctl.idgen_delay);
2074 		in6_ifa_put(ifp2);
2075 lock_errdad:
2076 		spin_lock_bh(&ifp->lock);
2077 	}
2078 
2079 errdad:
2080 	/* transition from _POSTDAD to _ERRDAD */
2081 	ifp->state = INET6_IFADDR_STATE_ERRDAD;
2082 	spin_unlock_bh(&ifp->lock);
2083 
2084 	addrconf_mod_dad_work(ifp, 0);
2085 	in6_ifa_put(ifp);
2086 }
2087 
2088 /* Join to solicited addr multicast group.
2089  * caller must hold RTNL */
2090 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
2091 {
2092 	struct in6_addr maddr;
2093 
2094 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2095 		return;
2096 
2097 	addrconf_addr_solict_mult(addr, &maddr);
2098 	ipv6_dev_mc_inc(dev, &maddr);
2099 }
2100 
2101 /* caller must hold RTNL */
2102 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
2103 {
2104 	struct in6_addr maddr;
2105 
2106 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2107 		return;
2108 
2109 	addrconf_addr_solict_mult(addr, &maddr);
2110 	__ipv6_dev_mc_dec(idev, &maddr);
2111 }
2112 
2113 /* caller must hold RTNL */
2114 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
2115 {
2116 	struct in6_addr addr;
2117 
2118 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2119 		return;
2120 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2121 	if (ipv6_addr_any(&addr))
2122 		return;
2123 	__ipv6_dev_ac_inc(ifp->idev, &addr);
2124 }
2125 
2126 /* caller must hold RTNL */
2127 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
2128 {
2129 	struct in6_addr addr;
2130 
2131 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2132 		return;
2133 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2134 	if (ipv6_addr_any(&addr))
2135 		return;
2136 	__ipv6_dev_ac_dec(ifp->idev, &addr);
2137 }
2138 
2139 static int addrconf_ifid_6lowpan(u8 *eui, struct net_device *dev)
2140 {
2141 	switch (dev->addr_len) {
2142 	case ETH_ALEN:
2143 		memcpy(eui, dev->dev_addr, 3);
2144 		eui[3] = 0xFF;
2145 		eui[4] = 0xFE;
2146 		memcpy(eui + 5, dev->dev_addr + 3, 3);
2147 		break;
2148 	case EUI64_ADDR_LEN:
2149 		memcpy(eui, dev->dev_addr, EUI64_ADDR_LEN);
2150 		eui[0] ^= 2;
2151 		break;
2152 	default:
2153 		return -1;
2154 	}
2155 
2156 	return 0;
2157 }
2158 
2159 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
2160 {
2161 	union fwnet_hwaddr *ha;
2162 
2163 	if (dev->addr_len != FWNET_ALEN)
2164 		return -1;
2165 
2166 	ha = (union fwnet_hwaddr *)dev->dev_addr;
2167 
2168 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
2169 	eui[0] ^= 2;
2170 	return 0;
2171 }
2172 
2173 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
2174 {
2175 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
2176 	if (dev->addr_len != ARCNET_ALEN)
2177 		return -1;
2178 	memset(eui, 0, 7);
2179 	eui[7] = *(u8 *)dev->dev_addr;
2180 	return 0;
2181 }
2182 
2183 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
2184 {
2185 	if (dev->addr_len != INFINIBAND_ALEN)
2186 		return -1;
2187 	memcpy(eui, dev->dev_addr + 12, 8);
2188 	eui[0] |= 2;
2189 	return 0;
2190 }
2191 
2192 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
2193 {
2194 	if (addr == 0)
2195 		return -1;
2196 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
2197 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
2198 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
2199 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
2200 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
2201 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
2202 	eui[1] = 0;
2203 	eui[2] = 0x5E;
2204 	eui[3] = 0xFE;
2205 	memcpy(eui + 4, &addr, 4);
2206 	return 0;
2207 }
2208 
2209 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
2210 {
2211 	if (dev->priv_flags & IFF_ISATAP)
2212 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2213 	return -1;
2214 }
2215 
2216 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
2217 {
2218 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2219 }
2220 
2221 static int addrconf_ifid_ip6tnl(u8 *eui, struct net_device *dev)
2222 {
2223 	memcpy(eui, dev->perm_addr, 3);
2224 	memcpy(eui + 5, dev->perm_addr + 3, 3);
2225 	eui[3] = 0xFF;
2226 	eui[4] = 0xFE;
2227 	eui[0] ^= 2;
2228 	return 0;
2229 }
2230 
2231 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
2232 {
2233 	switch (dev->type) {
2234 	case ARPHRD_ETHER:
2235 	case ARPHRD_FDDI:
2236 		return addrconf_ifid_eui48(eui, dev);
2237 	case ARPHRD_ARCNET:
2238 		return addrconf_ifid_arcnet(eui, dev);
2239 	case ARPHRD_INFINIBAND:
2240 		return addrconf_ifid_infiniband(eui, dev);
2241 	case ARPHRD_SIT:
2242 		return addrconf_ifid_sit(eui, dev);
2243 	case ARPHRD_IPGRE:
2244 	case ARPHRD_TUNNEL:
2245 		return addrconf_ifid_gre(eui, dev);
2246 	case ARPHRD_6LOWPAN:
2247 		return addrconf_ifid_6lowpan(eui, dev);
2248 	case ARPHRD_IEEE1394:
2249 		return addrconf_ifid_ieee1394(eui, dev);
2250 	case ARPHRD_TUNNEL6:
2251 	case ARPHRD_IP6GRE:
2252 	case ARPHRD_RAWIP:
2253 		return addrconf_ifid_ip6tnl(eui, dev);
2254 	}
2255 	return -1;
2256 }
2257 
2258 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
2259 {
2260 	int err = -1;
2261 	struct inet6_ifaddr *ifp;
2262 
2263 	read_lock_bh(&idev->lock);
2264 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
2265 		if (ifp->scope > IFA_LINK)
2266 			break;
2267 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
2268 			memcpy(eui, ifp->addr.s6_addr+8, 8);
2269 			err = 0;
2270 			break;
2271 		}
2272 	}
2273 	read_unlock_bh(&idev->lock);
2274 	return err;
2275 }
2276 
2277 /* (re)generation of randomized interface identifier (RFC 3041 3.2, 3.5) */
2278 static void ipv6_regen_rndid(struct inet6_dev *idev)
2279 {
2280 regen:
2281 	get_random_bytes(idev->rndid, sizeof(idev->rndid));
2282 	idev->rndid[0] &= ~0x02;
2283 
2284 	/*
2285 	 * <draft-ietf-ipngwg-temp-addresses-v2-00.txt>:
2286 	 * check if generated address is not inappropriate
2287 	 *
2288 	 *  - Reserved subnet anycast (RFC 2526)
2289 	 *	11111101 11....11 1xxxxxxx
2290 	 *  - ISATAP (RFC4214) 6.1
2291 	 *	00-00-5E-FE-xx-xx-xx-xx
2292 	 *  - value 0
2293 	 *  - XXX: already assigned to an address on the device
2294 	 */
2295 	if (idev->rndid[0] == 0xfd &&
2296 	    (idev->rndid[1]&idev->rndid[2]&idev->rndid[3]&idev->rndid[4]&idev->rndid[5]&idev->rndid[6]) == 0xff &&
2297 	    (idev->rndid[7]&0x80))
2298 		goto regen;
2299 	if ((idev->rndid[0]|idev->rndid[1]) == 0) {
2300 		if (idev->rndid[2] == 0x5e && idev->rndid[3] == 0xfe)
2301 			goto regen;
2302 		if ((idev->rndid[2]|idev->rndid[3]|idev->rndid[4]|idev->rndid[5]|idev->rndid[6]|idev->rndid[7]) == 0x00)
2303 			goto regen;
2304 	}
2305 }
2306 
2307 static void  ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr)
2308 {
2309 	if (tmpaddr && memcmp(idev->rndid, &tmpaddr->s6_addr[8], 8) == 0)
2310 		ipv6_regen_rndid(idev);
2311 }
2312 
2313 /*
2314  *	Add prefix route.
2315  */
2316 
2317 static void
2318 addrconf_prefix_route(struct in6_addr *pfx, int plen, u32 metric,
2319 		      struct net_device *dev, unsigned long expires,
2320 		      u32 flags, gfp_t gfp_flags)
2321 {
2322 	struct fib6_config cfg = {
2323 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX,
2324 		.fc_metric = metric ? : IP6_RT_PRIO_ADDRCONF,
2325 		.fc_ifindex = dev->ifindex,
2326 		.fc_expires = expires,
2327 		.fc_dst_len = plen,
2328 		.fc_flags = RTF_UP | flags,
2329 		.fc_nlinfo.nl_net = dev_net(dev),
2330 		.fc_protocol = RTPROT_KERNEL,
2331 		.fc_type = RTN_UNICAST,
2332 	};
2333 
2334 	cfg.fc_dst = *pfx;
2335 
2336 	/* Prevent useless cloning on PtP SIT.
2337 	   This thing is done here expecting that the whole
2338 	   class of non-broadcast devices need not cloning.
2339 	 */
2340 #if IS_ENABLED(CONFIG_IPV6_SIT)
2341 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
2342 		cfg.fc_flags |= RTF_NONEXTHOP;
2343 #endif
2344 
2345 	ip6_route_add(&cfg, gfp_flags, NULL);
2346 }
2347 
2348 
2349 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
2350 						  int plen,
2351 						  const struct net_device *dev,
2352 						  u32 flags, u32 noflags)
2353 {
2354 	struct fib6_node *fn;
2355 	struct fib6_info *rt = NULL;
2356 	struct fib6_table *table;
2357 	u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX;
2358 
2359 	table = fib6_get_table(dev_net(dev), tb_id);
2360 	if (!table)
2361 		return NULL;
2362 
2363 	rcu_read_lock();
2364 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0, true);
2365 	if (!fn)
2366 		goto out;
2367 
2368 	for_each_fib6_node_rt_rcu(fn) {
2369 		if (rt->fib6_nh.nh_dev->ifindex != dev->ifindex)
2370 			continue;
2371 		if ((rt->fib6_flags & flags) != flags)
2372 			continue;
2373 		if ((rt->fib6_flags & noflags) != 0)
2374 			continue;
2375 		fib6_info_hold(rt);
2376 		break;
2377 	}
2378 out:
2379 	rcu_read_unlock();
2380 	return rt;
2381 }
2382 
2383 
2384 /* Create "default" multicast route to the interface */
2385 
2386 static void addrconf_add_mroute(struct net_device *dev)
2387 {
2388 	struct fib6_config cfg = {
2389 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_LOCAL,
2390 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2391 		.fc_ifindex = dev->ifindex,
2392 		.fc_dst_len = 8,
2393 		.fc_flags = RTF_UP,
2394 		.fc_type = RTN_UNICAST,
2395 		.fc_nlinfo.nl_net = dev_net(dev),
2396 	};
2397 
2398 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
2399 
2400 	ip6_route_add(&cfg, GFP_ATOMIC, NULL);
2401 }
2402 
2403 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2404 {
2405 	struct inet6_dev *idev;
2406 
2407 	ASSERT_RTNL();
2408 
2409 	idev = ipv6_find_idev(dev);
2410 	if (!idev)
2411 		return ERR_PTR(-ENOBUFS);
2412 
2413 	if (idev->cnf.disable_ipv6)
2414 		return ERR_PTR(-EACCES);
2415 
2416 	/* Add default multicast route */
2417 	if (!(dev->flags & IFF_LOOPBACK) && !netif_is_l3_master(dev))
2418 		addrconf_add_mroute(dev);
2419 
2420 	return idev;
2421 }
2422 
2423 static void manage_tempaddrs(struct inet6_dev *idev,
2424 			     struct inet6_ifaddr *ifp,
2425 			     __u32 valid_lft, __u32 prefered_lft,
2426 			     bool create, unsigned long now)
2427 {
2428 	u32 flags;
2429 	struct inet6_ifaddr *ift;
2430 
2431 	read_lock_bh(&idev->lock);
2432 	/* update all temporary addresses in the list */
2433 	list_for_each_entry(ift, &idev->tempaddr_list, tmp_list) {
2434 		int age, max_valid, max_prefered;
2435 
2436 		if (ifp != ift->ifpub)
2437 			continue;
2438 
2439 		/* RFC 4941 section 3.3:
2440 		 * If a received option will extend the lifetime of a public
2441 		 * address, the lifetimes of temporary addresses should
2442 		 * be extended, subject to the overall constraint that no
2443 		 * temporary addresses should ever remain "valid" or "preferred"
2444 		 * for a time longer than (TEMP_VALID_LIFETIME) or
2445 		 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR), respectively.
2446 		 */
2447 		age = (now - ift->cstamp) / HZ;
2448 		max_valid = idev->cnf.temp_valid_lft - age;
2449 		if (max_valid < 0)
2450 			max_valid = 0;
2451 
2452 		max_prefered = idev->cnf.temp_prefered_lft -
2453 			       idev->desync_factor - age;
2454 		if (max_prefered < 0)
2455 			max_prefered = 0;
2456 
2457 		if (valid_lft > max_valid)
2458 			valid_lft = max_valid;
2459 
2460 		if (prefered_lft > max_prefered)
2461 			prefered_lft = max_prefered;
2462 
2463 		spin_lock(&ift->lock);
2464 		flags = ift->flags;
2465 		ift->valid_lft = valid_lft;
2466 		ift->prefered_lft = prefered_lft;
2467 		ift->tstamp = now;
2468 		if (prefered_lft > 0)
2469 			ift->flags &= ~IFA_F_DEPRECATED;
2470 
2471 		spin_unlock(&ift->lock);
2472 		if (!(flags&IFA_F_TENTATIVE))
2473 			ipv6_ifa_notify(0, ift);
2474 	}
2475 
2476 	if ((create || list_empty(&idev->tempaddr_list)) &&
2477 	    idev->cnf.use_tempaddr > 0) {
2478 		/* When a new public address is created as described
2479 		 * in [ADDRCONF], also create a new temporary address.
2480 		 * Also create a temporary address if it's enabled but
2481 		 * no temporary address currently exists.
2482 		 */
2483 		read_unlock_bh(&idev->lock);
2484 		ipv6_create_tempaddr(ifp, NULL, false);
2485 	} else {
2486 		read_unlock_bh(&idev->lock);
2487 	}
2488 }
2489 
2490 static bool is_addr_mode_generate_stable(struct inet6_dev *idev)
2491 {
2492 	return idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY ||
2493 	       idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_RANDOM;
2494 }
2495 
2496 int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
2497 				 const struct prefix_info *pinfo,
2498 				 struct inet6_dev *in6_dev,
2499 				 const struct in6_addr *addr, int addr_type,
2500 				 u32 addr_flags, bool sllao, bool tokenized,
2501 				 __u32 valid_lft, u32 prefered_lft)
2502 {
2503 	struct inet6_ifaddr *ifp = ipv6_get_ifaddr(net, addr, dev, 1);
2504 	int create = 0, update_lft = 0;
2505 
2506 	if (!ifp && valid_lft) {
2507 		int max_addresses = in6_dev->cnf.max_addresses;
2508 		struct ifa6_config cfg = {
2509 			.pfx = addr,
2510 			.plen = pinfo->prefix_len,
2511 			.ifa_flags = addr_flags,
2512 			.valid_lft = valid_lft,
2513 			.preferred_lft = prefered_lft,
2514 			.scope = addr_type & IPV6_ADDR_SCOPE_MASK,
2515 		};
2516 
2517 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2518 		if ((net->ipv6.devconf_all->optimistic_dad ||
2519 		     in6_dev->cnf.optimistic_dad) &&
2520 		    !net->ipv6.devconf_all->forwarding && sllao)
2521 			cfg.ifa_flags |= IFA_F_OPTIMISTIC;
2522 #endif
2523 
2524 		/* Do not allow to create too much of autoconfigured
2525 		 * addresses; this would be too easy way to crash kernel.
2526 		 */
2527 		if (!max_addresses ||
2528 		    ipv6_count_addresses(in6_dev) < max_addresses)
2529 			ifp = ipv6_add_addr(in6_dev, &cfg, false, NULL);
2530 
2531 		if (IS_ERR_OR_NULL(ifp))
2532 			return -1;
2533 
2534 		create = 1;
2535 		spin_lock_bh(&ifp->lock);
2536 		ifp->flags |= IFA_F_MANAGETEMPADDR;
2537 		ifp->cstamp = jiffies;
2538 		ifp->tokenized = tokenized;
2539 		spin_unlock_bh(&ifp->lock);
2540 		addrconf_dad_start(ifp);
2541 	}
2542 
2543 	if (ifp) {
2544 		u32 flags;
2545 		unsigned long now;
2546 		u32 stored_lft;
2547 
2548 		/* update lifetime (RFC2462 5.5.3 e) */
2549 		spin_lock_bh(&ifp->lock);
2550 		now = jiffies;
2551 		if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2552 			stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2553 		else
2554 			stored_lft = 0;
2555 		if (!create && stored_lft) {
2556 			const u32 minimum_lft = min_t(u32,
2557 				stored_lft, MIN_VALID_LIFETIME);
2558 			valid_lft = max(valid_lft, minimum_lft);
2559 
2560 			/* RFC4862 Section 5.5.3e:
2561 			 * "Note that the preferred lifetime of the
2562 			 *  corresponding address is always reset to
2563 			 *  the Preferred Lifetime in the received
2564 			 *  Prefix Information option, regardless of
2565 			 *  whether the valid lifetime is also reset or
2566 			 *  ignored."
2567 			 *
2568 			 * So we should always update prefered_lft here.
2569 			 */
2570 			update_lft = 1;
2571 		}
2572 
2573 		if (update_lft) {
2574 			ifp->valid_lft = valid_lft;
2575 			ifp->prefered_lft = prefered_lft;
2576 			ifp->tstamp = now;
2577 			flags = ifp->flags;
2578 			ifp->flags &= ~IFA_F_DEPRECATED;
2579 			spin_unlock_bh(&ifp->lock);
2580 
2581 			if (!(flags&IFA_F_TENTATIVE))
2582 				ipv6_ifa_notify(0, ifp);
2583 		} else
2584 			spin_unlock_bh(&ifp->lock);
2585 
2586 		manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
2587 				 create, now);
2588 
2589 		in6_ifa_put(ifp);
2590 		addrconf_verify();
2591 	}
2592 
2593 	return 0;
2594 }
2595 EXPORT_SYMBOL_GPL(addrconf_prefix_rcv_add_addr);
2596 
2597 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2598 {
2599 	struct prefix_info *pinfo;
2600 	__u32 valid_lft;
2601 	__u32 prefered_lft;
2602 	int addr_type, err;
2603 	u32 addr_flags = 0;
2604 	struct inet6_dev *in6_dev;
2605 	struct net *net = dev_net(dev);
2606 
2607 	pinfo = (struct prefix_info *) opt;
2608 
2609 	if (len < sizeof(struct prefix_info)) {
2610 		netdev_dbg(dev, "addrconf: prefix option too short\n");
2611 		return;
2612 	}
2613 
2614 	/*
2615 	 *	Validation checks ([ADDRCONF], page 19)
2616 	 */
2617 
2618 	addr_type = ipv6_addr_type(&pinfo->prefix);
2619 
2620 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2621 		return;
2622 
2623 	valid_lft = ntohl(pinfo->valid);
2624 	prefered_lft = ntohl(pinfo->prefered);
2625 
2626 	if (prefered_lft > valid_lft) {
2627 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2628 		return;
2629 	}
2630 
2631 	in6_dev = in6_dev_get(dev);
2632 
2633 	if (!in6_dev) {
2634 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2635 				    dev->name);
2636 		return;
2637 	}
2638 
2639 	/*
2640 	 *	Two things going on here:
2641 	 *	1) Add routes for on-link prefixes
2642 	 *	2) Configure prefixes with the auto flag set
2643 	 */
2644 
2645 	if (pinfo->onlink) {
2646 		struct fib6_info *rt;
2647 		unsigned long rt_expires;
2648 
2649 		/* Avoid arithmetic overflow. Really, we could
2650 		 * save rt_expires in seconds, likely valid_lft,
2651 		 * but it would require division in fib gc, that it
2652 		 * not good.
2653 		 */
2654 		if (HZ > USER_HZ)
2655 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2656 		else
2657 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2658 
2659 		if (addrconf_finite_timeout(rt_expires))
2660 			rt_expires *= HZ;
2661 
2662 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2663 					       pinfo->prefix_len,
2664 					       dev,
2665 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2666 					       RTF_GATEWAY | RTF_DEFAULT);
2667 
2668 		if (rt) {
2669 			/* Autoconf prefix route */
2670 			if (valid_lft == 0) {
2671 				ip6_del_rt(net, rt);
2672 				rt = NULL;
2673 			} else if (addrconf_finite_timeout(rt_expires)) {
2674 				/* not infinity */
2675 				fib6_set_expires(rt, jiffies + rt_expires);
2676 			} else {
2677 				fib6_clean_expires(rt);
2678 			}
2679 		} else if (valid_lft) {
2680 			clock_t expires = 0;
2681 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2682 			if (addrconf_finite_timeout(rt_expires)) {
2683 				/* not infinity */
2684 				flags |= RTF_EXPIRES;
2685 				expires = jiffies_to_clock_t(rt_expires);
2686 			}
2687 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2688 					      0, dev, expires, flags,
2689 					      GFP_ATOMIC);
2690 		}
2691 		fib6_info_release(rt);
2692 	}
2693 
2694 	/* Try to figure out our local address for this prefix */
2695 
2696 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
2697 		struct in6_addr addr;
2698 		bool tokenized = false, dev_addr_generated = false;
2699 
2700 		if (pinfo->prefix_len == 64) {
2701 			memcpy(&addr, &pinfo->prefix, 8);
2702 
2703 			if (!ipv6_addr_any(&in6_dev->token)) {
2704 				read_lock_bh(&in6_dev->lock);
2705 				memcpy(addr.s6_addr + 8,
2706 				       in6_dev->token.s6_addr + 8, 8);
2707 				read_unlock_bh(&in6_dev->lock);
2708 				tokenized = true;
2709 			} else if (is_addr_mode_generate_stable(in6_dev) &&
2710 				   !ipv6_generate_stable_address(&addr, 0,
2711 								 in6_dev)) {
2712 				addr_flags |= IFA_F_STABLE_PRIVACY;
2713 				goto ok;
2714 			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2715 				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2716 				goto put;
2717 			} else {
2718 				dev_addr_generated = true;
2719 			}
2720 			goto ok;
2721 		}
2722 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2723 				    pinfo->prefix_len);
2724 		goto put;
2725 
2726 ok:
2727 		err = addrconf_prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
2728 						   &addr, addr_type,
2729 						   addr_flags, sllao,
2730 						   tokenized, valid_lft,
2731 						   prefered_lft);
2732 		if (err)
2733 			goto put;
2734 
2735 		/* Ignore error case here because previous prefix add addr was
2736 		 * successful which will be notified.
2737 		 */
2738 		ndisc_ops_prefix_rcv_add_addr(net, dev, pinfo, in6_dev, &addr,
2739 					      addr_type, addr_flags, sllao,
2740 					      tokenized, valid_lft,
2741 					      prefered_lft,
2742 					      dev_addr_generated);
2743 	}
2744 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2745 put:
2746 	in6_dev_put(in6_dev);
2747 }
2748 
2749 /*
2750  *	Set destination address.
2751  *	Special case for SIT interfaces where we create a new "virtual"
2752  *	device.
2753  */
2754 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2755 {
2756 	struct in6_ifreq ireq;
2757 	struct net_device *dev;
2758 	int err = -EINVAL;
2759 
2760 	rtnl_lock();
2761 
2762 	err = -EFAULT;
2763 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2764 		goto err_exit;
2765 
2766 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2767 
2768 	err = -ENODEV;
2769 	if (!dev)
2770 		goto err_exit;
2771 
2772 #if IS_ENABLED(CONFIG_IPV6_SIT)
2773 	if (dev->type == ARPHRD_SIT) {
2774 		const struct net_device_ops *ops = dev->netdev_ops;
2775 		struct ifreq ifr;
2776 		struct ip_tunnel_parm p;
2777 
2778 		err = -EADDRNOTAVAIL;
2779 		if (!(ipv6_addr_type(&ireq.ifr6_addr) & IPV6_ADDR_COMPATv4))
2780 			goto err_exit;
2781 
2782 		memset(&p, 0, sizeof(p));
2783 		p.iph.daddr = ireq.ifr6_addr.s6_addr32[3];
2784 		p.iph.saddr = 0;
2785 		p.iph.version = 4;
2786 		p.iph.ihl = 5;
2787 		p.iph.protocol = IPPROTO_IPV6;
2788 		p.iph.ttl = 64;
2789 		ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
2790 
2791 		if (ops->ndo_do_ioctl) {
2792 			mm_segment_t oldfs = get_fs();
2793 
2794 			set_fs(KERNEL_DS);
2795 			err = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
2796 			set_fs(oldfs);
2797 		} else
2798 			err = -EOPNOTSUPP;
2799 
2800 		if (err == 0) {
2801 			err = -ENOBUFS;
2802 			dev = __dev_get_by_name(net, p.name);
2803 			if (!dev)
2804 				goto err_exit;
2805 			err = dev_open(dev);
2806 		}
2807 	}
2808 #endif
2809 
2810 err_exit:
2811 	rtnl_unlock();
2812 	return err;
2813 }
2814 
2815 static int ipv6_mc_config(struct sock *sk, bool join,
2816 			  const struct in6_addr *addr, int ifindex)
2817 {
2818 	int ret;
2819 
2820 	ASSERT_RTNL();
2821 
2822 	lock_sock(sk);
2823 	if (join)
2824 		ret = ipv6_sock_mc_join(sk, ifindex, addr);
2825 	else
2826 		ret = ipv6_sock_mc_drop(sk, ifindex, addr);
2827 	release_sock(sk);
2828 
2829 	return ret;
2830 }
2831 
2832 /*
2833  *	Manual configuration of address on an interface
2834  */
2835 static int inet6_addr_add(struct net *net, int ifindex,
2836 			  struct ifa6_config *cfg,
2837 			  struct netlink_ext_ack *extack)
2838 {
2839 	struct inet6_ifaddr *ifp;
2840 	struct inet6_dev *idev;
2841 	struct net_device *dev;
2842 	unsigned long timeout;
2843 	clock_t expires;
2844 	u32 flags;
2845 
2846 	ASSERT_RTNL();
2847 
2848 	if (cfg->plen > 128)
2849 		return -EINVAL;
2850 
2851 	/* check the lifetime */
2852 	if (!cfg->valid_lft || cfg->preferred_lft > cfg->valid_lft)
2853 		return -EINVAL;
2854 
2855 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR && cfg->plen != 64)
2856 		return -EINVAL;
2857 
2858 	dev = __dev_get_by_index(net, ifindex);
2859 	if (!dev)
2860 		return -ENODEV;
2861 
2862 	idev = addrconf_add_dev(dev);
2863 	if (IS_ERR(idev))
2864 		return PTR_ERR(idev);
2865 
2866 	if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
2867 		int ret = ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2868 					 true, cfg->pfx, ifindex);
2869 
2870 		if (ret < 0)
2871 			return ret;
2872 	}
2873 
2874 	cfg->scope = ipv6_addr_scope(cfg->pfx);
2875 
2876 	timeout = addrconf_timeout_fixup(cfg->valid_lft, HZ);
2877 	if (addrconf_finite_timeout(timeout)) {
2878 		expires = jiffies_to_clock_t(timeout * HZ);
2879 		cfg->valid_lft = timeout;
2880 		flags = RTF_EXPIRES;
2881 	} else {
2882 		expires = 0;
2883 		flags = 0;
2884 		cfg->ifa_flags |= IFA_F_PERMANENT;
2885 	}
2886 
2887 	timeout = addrconf_timeout_fixup(cfg->preferred_lft, HZ);
2888 	if (addrconf_finite_timeout(timeout)) {
2889 		if (timeout == 0)
2890 			cfg->ifa_flags |= IFA_F_DEPRECATED;
2891 		cfg->preferred_lft = timeout;
2892 	}
2893 
2894 	ifp = ipv6_add_addr(idev, cfg, true, extack);
2895 	if (!IS_ERR(ifp)) {
2896 		if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
2897 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
2898 					      ifp->rt_priority, dev, expires,
2899 					      flags, GFP_KERNEL);
2900 		}
2901 
2902 		/* Send a netlink notification if DAD is enabled and
2903 		 * optimistic flag is not set
2904 		 */
2905 		if (!(ifp->flags & (IFA_F_OPTIMISTIC | IFA_F_NODAD)))
2906 			ipv6_ifa_notify(0, ifp);
2907 		/*
2908 		 * Note that section 3.1 of RFC 4429 indicates
2909 		 * that the Optimistic flag should not be set for
2910 		 * manually configured addresses
2911 		 */
2912 		addrconf_dad_start(ifp);
2913 		if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR)
2914 			manage_tempaddrs(idev, ifp, cfg->valid_lft,
2915 					 cfg->preferred_lft, true, jiffies);
2916 		in6_ifa_put(ifp);
2917 		addrconf_verify_rtnl();
2918 		return 0;
2919 	} else if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
2920 		ipv6_mc_config(net->ipv6.mc_autojoin_sk, false,
2921 			       cfg->pfx, ifindex);
2922 	}
2923 
2924 	return PTR_ERR(ifp);
2925 }
2926 
2927 static int inet6_addr_del(struct net *net, int ifindex, u32 ifa_flags,
2928 			  const struct in6_addr *pfx, unsigned int plen)
2929 {
2930 	struct inet6_ifaddr *ifp;
2931 	struct inet6_dev *idev;
2932 	struct net_device *dev;
2933 
2934 	if (plen > 128)
2935 		return -EINVAL;
2936 
2937 	dev = __dev_get_by_index(net, ifindex);
2938 	if (!dev)
2939 		return -ENODEV;
2940 
2941 	idev = __in6_dev_get(dev);
2942 	if (!idev)
2943 		return -ENXIO;
2944 
2945 	read_lock_bh(&idev->lock);
2946 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
2947 		if (ifp->prefix_len == plen &&
2948 		    ipv6_addr_equal(pfx, &ifp->addr)) {
2949 			in6_ifa_hold(ifp);
2950 			read_unlock_bh(&idev->lock);
2951 
2952 			if (!(ifp->flags & IFA_F_TEMPORARY) &&
2953 			    (ifa_flags & IFA_F_MANAGETEMPADDR))
2954 				manage_tempaddrs(idev, ifp, 0, 0, false,
2955 						 jiffies);
2956 			ipv6_del_addr(ifp);
2957 			addrconf_verify_rtnl();
2958 			if (ipv6_addr_is_multicast(pfx)) {
2959 				ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2960 					       false, pfx, dev->ifindex);
2961 			}
2962 			return 0;
2963 		}
2964 	}
2965 	read_unlock_bh(&idev->lock);
2966 	return -EADDRNOTAVAIL;
2967 }
2968 
2969 
2970 int addrconf_add_ifaddr(struct net *net, void __user *arg)
2971 {
2972 	struct ifa6_config cfg = {
2973 		.ifa_flags = IFA_F_PERMANENT,
2974 		.preferred_lft = INFINITY_LIFE_TIME,
2975 		.valid_lft = INFINITY_LIFE_TIME,
2976 	};
2977 	struct in6_ifreq ireq;
2978 	int err;
2979 
2980 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2981 		return -EPERM;
2982 
2983 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2984 		return -EFAULT;
2985 
2986 	cfg.pfx = &ireq.ifr6_addr;
2987 	cfg.plen = ireq.ifr6_prefixlen;
2988 
2989 	rtnl_lock();
2990 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &cfg, NULL);
2991 	rtnl_unlock();
2992 	return err;
2993 }
2994 
2995 int addrconf_del_ifaddr(struct net *net, void __user *arg)
2996 {
2997 	struct in6_ifreq ireq;
2998 	int err;
2999 
3000 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3001 		return -EPERM;
3002 
3003 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3004 		return -EFAULT;
3005 
3006 	rtnl_lock();
3007 	err = inet6_addr_del(net, ireq.ifr6_ifindex, 0, &ireq.ifr6_addr,
3008 			     ireq.ifr6_prefixlen);
3009 	rtnl_unlock();
3010 	return err;
3011 }
3012 
3013 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
3014 		     int plen, int scope)
3015 {
3016 	struct inet6_ifaddr *ifp;
3017 	struct ifa6_config cfg = {
3018 		.pfx = addr,
3019 		.plen = plen,
3020 		.ifa_flags = IFA_F_PERMANENT,
3021 		.valid_lft = INFINITY_LIFE_TIME,
3022 		.preferred_lft = INFINITY_LIFE_TIME,
3023 		.scope = scope
3024 	};
3025 
3026 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3027 	if (!IS_ERR(ifp)) {
3028 		spin_lock_bh(&ifp->lock);
3029 		ifp->flags &= ~IFA_F_TENTATIVE;
3030 		spin_unlock_bh(&ifp->lock);
3031 		rt_genid_bump_ipv6(dev_net(idev->dev));
3032 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3033 		in6_ifa_put(ifp);
3034 	}
3035 }
3036 
3037 #if IS_ENABLED(CONFIG_IPV6_SIT)
3038 static void sit_add_v4_addrs(struct inet6_dev *idev)
3039 {
3040 	struct in6_addr addr;
3041 	struct net_device *dev;
3042 	struct net *net = dev_net(idev->dev);
3043 	int scope, plen;
3044 	u32 pflags = 0;
3045 
3046 	ASSERT_RTNL();
3047 
3048 	memset(&addr, 0, sizeof(struct in6_addr));
3049 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
3050 
3051 	if (idev->dev->flags&IFF_POINTOPOINT) {
3052 		addr.s6_addr32[0] = htonl(0xfe800000);
3053 		scope = IFA_LINK;
3054 		plen = 64;
3055 	} else {
3056 		scope = IPV6_ADDR_COMPATv4;
3057 		plen = 96;
3058 		pflags |= RTF_NONEXTHOP;
3059 	}
3060 
3061 	if (addr.s6_addr32[3]) {
3062 		add_addr(idev, &addr, plen, scope);
3063 		addrconf_prefix_route(&addr, plen, 0, idev->dev, 0, pflags,
3064 				      GFP_ATOMIC);
3065 		return;
3066 	}
3067 
3068 	for_each_netdev(net, dev) {
3069 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
3070 		if (in_dev && (dev->flags & IFF_UP)) {
3071 			struct in_ifaddr *ifa;
3072 
3073 			int flag = scope;
3074 
3075 			for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
3076 
3077 				addr.s6_addr32[3] = ifa->ifa_local;
3078 
3079 				if (ifa->ifa_scope == RT_SCOPE_LINK)
3080 					continue;
3081 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
3082 					if (idev->dev->flags&IFF_POINTOPOINT)
3083 						continue;
3084 					flag |= IFA_HOST;
3085 				}
3086 
3087 				add_addr(idev, &addr, plen, flag);
3088 				addrconf_prefix_route(&addr, plen, 0, idev->dev,
3089 						      0, pflags, GFP_ATOMIC);
3090 			}
3091 		}
3092 	}
3093 }
3094 #endif
3095 
3096 static void init_loopback(struct net_device *dev)
3097 {
3098 	struct inet6_dev  *idev;
3099 
3100 	/* ::1 */
3101 
3102 	ASSERT_RTNL();
3103 
3104 	idev = ipv6_find_idev(dev);
3105 	if (!idev) {
3106 		pr_debug("%s: add_dev failed\n", __func__);
3107 		return;
3108 	}
3109 
3110 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST);
3111 }
3112 
3113 void addrconf_add_linklocal(struct inet6_dev *idev,
3114 			    const struct in6_addr *addr, u32 flags)
3115 {
3116 	struct ifa6_config cfg = {
3117 		.pfx = addr,
3118 		.plen = 64,
3119 		.ifa_flags = flags | IFA_F_PERMANENT,
3120 		.valid_lft = INFINITY_LIFE_TIME,
3121 		.preferred_lft = INFINITY_LIFE_TIME,
3122 		.scope = IFA_LINK
3123 	};
3124 	struct inet6_ifaddr *ifp;
3125 
3126 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
3127 	if ((dev_net(idev->dev)->ipv6.devconf_all->optimistic_dad ||
3128 	     idev->cnf.optimistic_dad) &&
3129 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
3130 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
3131 #endif
3132 
3133 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3134 	if (!IS_ERR(ifp)) {
3135 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, 0, idev->dev,
3136 				      0, 0, GFP_ATOMIC);
3137 		addrconf_dad_start(ifp);
3138 		in6_ifa_put(ifp);
3139 	}
3140 }
3141 EXPORT_SYMBOL_GPL(addrconf_add_linklocal);
3142 
3143 static bool ipv6_reserved_interfaceid(struct in6_addr address)
3144 {
3145 	if ((address.s6_addr32[2] | address.s6_addr32[3]) == 0)
3146 		return true;
3147 
3148 	if (address.s6_addr32[2] == htonl(0x02005eff) &&
3149 	    ((address.s6_addr32[3] & htonl(0xfe000000)) == htonl(0xfe000000)))
3150 		return true;
3151 
3152 	if (address.s6_addr32[2] == htonl(0xfdffffff) &&
3153 	    ((address.s6_addr32[3] & htonl(0xffffff80)) == htonl(0xffffff80)))
3154 		return true;
3155 
3156 	return false;
3157 }
3158 
3159 static int ipv6_generate_stable_address(struct in6_addr *address,
3160 					u8 dad_count,
3161 					const struct inet6_dev *idev)
3162 {
3163 	static DEFINE_SPINLOCK(lock);
3164 	static __u32 digest[SHA_DIGEST_WORDS];
3165 	static __u32 workspace[SHA_WORKSPACE_WORDS];
3166 
3167 	static union {
3168 		char __data[SHA_MESSAGE_BYTES];
3169 		struct {
3170 			struct in6_addr secret;
3171 			__be32 prefix[2];
3172 			unsigned char hwaddr[MAX_ADDR_LEN];
3173 			u8 dad_count;
3174 		} __packed;
3175 	} data;
3176 
3177 	struct in6_addr secret;
3178 	struct in6_addr temp;
3179 	struct net *net = dev_net(idev->dev);
3180 
3181 	BUILD_BUG_ON(sizeof(data.__data) != sizeof(data));
3182 
3183 	if (idev->cnf.stable_secret.initialized)
3184 		secret = idev->cnf.stable_secret.secret;
3185 	else if (net->ipv6.devconf_dflt->stable_secret.initialized)
3186 		secret = net->ipv6.devconf_dflt->stable_secret.secret;
3187 	else
3188 		return -1;
3189 
3190 retry:
3191 	spin_lock_bh(&lock);
3192 
3193 	sha_init(digest);
3194 	memset(&data, 0, sizeof(data));
3195 	memset(workspace, 0, sizeof(workspace));
3196 	memcpy(data.hwaddr, idev->dev->perm_addr, idev->dev->addr_len);
3197 	data.prefix[0] = address->s6_addr32[0];
3198 	data.prefix[1] = address->s6_addr32[1];
3199 	data.secret = secret;
3200 	data.dad_count = dad_count;
3201 
3202 	sha_transform(digest, data.__data, workspace);
3203 
3204 	temp = *address;
3205 	temp.s6_addr32[2] = (__force __be32)digest[0];
3206 	temp.s6_addr32[3] = (__force __be32)digest[1];
3207 
3208 	spin_unlock_bh(&lock);
3209 
3210 	if (ipv6_reserved_interfaceid(temp)) {
3211 		dad_count++;
3212 		if (dad_count > dev_net(idev->dev)->ipv6.sysctl.idgen_retries)
3213 			return -1;
3214 		goto retry;
3215 	}
3216 
3217 	*address = temp;
3218 	return 0;
3219 }
3220 
3221 static void ipv6_gen_mode_random_init(struct inet6_dev *idev)
3222 {
3223 	struct ipv6_stable_secret *s = &idev->cnf.stable_secret;
3224 
3225 	if (s->initialized)
3226 		return;
3227 	s = &idev->cnf.stable_secret;
3228 	get_random_bytes(&s->secret, sizeof(s->secret));
3229 	s->initialized = true;
3230 }
3231 
3232 static void addrconf_addr_gen(struct inet6_dev *idev, bool prefix_route)
3233 {
3234 	struct in6_addr addr;
3235 
3236 	/* no link local addresses on L3 master devices */
3237 	if (netif_is_l3_master(idev->dev))
3238 		return;
3239 
3240 	ipv6_addr_set(&addr, htonl(0xFE800000), 0, 0, 0);
3241 
3242 	switch (idev->cnf.addr_gen_mode) {
3243 	case IN6_ADDR_GEN_MODE_RANDOM:
3244 		ipv6_gen_mode_random_init(idev);
3245 		/* fallthrough */
3246 	case IN6_ADDR_GEN_MODE_STABLE_PRIVACY:
3247 		if (!ipv6_generate_stable_address(&addr, 0, idev))
3248 			addrconf_add_linklocal(idev, &addr,
3249 					       IFA_F_STABLE_PRIVACY);
3250 		else if (prefix_route)
3251 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3252 					      0, 0, GFP_KERNEL);
3253 		break;
3254 	case IN6_ADDR_GEN_MODE_EUI64:
3255 		/* addrconf_add_linklocal also adds a prefix_route and we
3256 		 * only need to care about prefix routes if ipv6_generate_eui64
3257 		 * couldn't generate one.
3258 		 */
3259 		if (ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) == 0)
3260 			addrconf_add_linklocal(idev, &addr, 0);
3261 		else if (prefix_route)
3262 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3263 					      0, 0, GFP_KERNEL);
3264 		break;
3265 	case IN6_ADDR_GEN_MODE_NONE:
3266 	default:
3267 		/* will not add any link local address */
3268 		break;
3269 	}
3270 }
3271 
3272 static void addrconf_dev_config(struct net_device *dev)
3273 {
3274 	struct inet6_dev *idev;
3275 
3276 	ASSERT_RTNL();
3277 
3278 	if ((dev->type != ARPHRD_ETHER) &&
3279 	    (dev->type != ARPHRD_FDDI) &&
3280 	    (dev->type != ARPHRD_ARCNET) &&
3281 	    (dev->type != ARPHRD_INFINIBAND) &&
3282 	    (dev->type != ARPHRD_IEEE1394) &&
3283 	    (dev->type != ARPHRD_TUNNEL6) &&
3284 	    (dev->type != ARPHRD_6LOWPAN) &&
3285 	    (dev->type != ARPHRD_IP6GRE) &&
3286 	    (dev->type != ARPHRD_IPGRE) &&
3287 	    (dev->type != ARPHRD_TUNNEL) &&
3288 	    (dev->type != ARPHRD_NONE) &&
3289 	    (dev->type != ARPHRD_RAWIP)) {
3290 		/* Alas, we support only Ethernet autoconfiguration. */
3291 		return;
3292 	}
3293 
3294 	idev = addrconf_add_dev(dev);
3295 	if (IS_ERR(idev))
3296 		return;
3297 
3298 	/* this device type has no EUI support */
3299 	if (dev->type == ARPHRD_NONE &&
3300 	    idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64)
3301 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_RANDOM;
3302 
3303 	addrconf_addr_gen(idev, false);
3304 }
3305 
3306 #if IS_ENABLED(CONFIG_IPV6_SIT)
3307 static void addrconf_sit_config(struct net_device *dev)
3308 {
3309 	struct inet6_dev *idev;
3310 
3311 	ASSERT_RTNL();
3312 
3313 	/*
3314 	 * Configure the tunnel with one of our IPv4
3315 	 * addresses... we should configure all of
3316 	 * our v4 addrs in the tunnel
3317 	 */
3318 
3319 	idev = ipv6_find_idev(dev);
3320 	if (!idev) {
3321 		pr_debug("%s: add_dev failed\n", __func__);
3322 		return;
3323 	}
3324 
3325 	if (dev->priv_flags & IFF_ISATAP) {
3326 		addrconf_addr_gen(idev, false);
3327 		return;
3328 	}
3329 
3330 	sit_add_v4_addrs(idev);
3331 
3332 	if (dev->flags&IFF_POINTOPOINT)
3333 		addrconf_add_mroute(dev);
3334 }
3335 #endif
3336 
3337 #if IS_ENABLED(CONFIG_NET_IPGRE)
3338 static void addrconf_gre_config(struct net_device *dev)
3339 {
3340 	struct inet6_dev *idev;
3341 
3342 	ASSERT_RTNL();
3343 
3344 	idev = ipv6_find_idev(dev);
3345 	if (!idev) {
3346 		pr_debug("%s: add_dev failed\n", __func__);
3347 		return;
3348 	}
3349 
3350 	addrconf_addr_gen(idev, true);
3351 	if (dev->flags & IFF_POINTOPOINT)
3352 		addrconf_add_mroute(dev);
3353 }
3354 #endif
3355 
3356 static int fixup_permanent_addr(struct net *net,
3357 				struct inet6_dev *idev,
3358 				struct inet6_ifaddr *ifp)
3359 {
3360 	/* !fib6_node means the host route was removed from the
3361 	 * FIB, for example, if 'lo' device is taken down. In that
3362 	 * case regenerate the host route.
3363 	 */
3364 	if (!ifp->rt || !ifp->rt->fib6_node) {
3365 		struct fib6_info *f6i, *prev;
3366 
3367 		f6i = addrconf_f6i_alloc(net, idev, &ifp->addr, false,
3368 					 GFP_ATOMIC);
3369 		if (IS_ERR(f6i))
3370 			return PTR_ERR(f6i);
3371 
3372 		/* ifp->rt can be accessed outside of rtnl */
3373 		spin_lock(&ifp->lock);
3374 		prev = ifp->rt;
3375 		ifp->rt = f6i;
3376 		spin_unlock(&ifp->lock);
3377 
3378 		fib6_info_release(prev);
3379 	}
3380 
3381 	if (!(ifp->flags & IFA_F_NOPREFIXROUTE)) {
3382 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3383 				      ifp->rt_priority, idev->dev, 0, 0,
3384 				      GFP_ATOMIC);
3385 	}
3386 
3387 	if (ifp->state == INET6_IFADDR_STATE_PREDAD)
3388 		addrconf_dad_start(ifp);
3389 
3390 	return 0;
3391 }
3392 
3393 static void addrconf_permanent_addr(struct net *net, struct net_device *dev)
3394 {
3395 	struct inet6_ifaddr *ifp, *tmp;
3396 	struct inet6_dev *idev;
3397 
3398 	idev = __in6_dev_get(dev);
3399 	if (!idev)
3400 		return;
3401 
3402 	write_lock_bh(&idev->lock);
3403 
3404 	list_for_each_entry_safe(ifp, tmp, &idev->addr_list, if_list) {
3405 		if ((ifp->flags & IFA_F_PERMANENT) &&
3406 		    fixup_permanent_addr(net, idev, ifp) < 0) {
3407 			write_unlock_bh(&idev->lock);
3408 			in6_ifa_hold(ifp);
3409 			ipv6_del_addr(ifp);
3410 			write_lock_bh(&idev->lock);
3411 
3412 			net_info_ratelimited("%s: Failed to add prefix route for address %pI6c; dropping\n",
3413 					     idev->dev->name, &ifp->addr);
3414 		}
3415 	}
3416 
3417 	write_unlock_bh(&idev->lock);
3418 }
3419 
3420 static int addrconf_notify(struct notifier_block *this, unsigned long event,
3421 			   void *ptr)
3422 {
3423 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3424 	struct netdev_notifier_changeupper_info *info;
3425 	struct inet6_dev *idev = __in6_dev_get(dev);
3426 	struct net *net = dev_net(dev);
3427 	int run_pending = 0;
3428 	int err;
3429 
3430 	switch (event) {
3431 	case NETDEV_REGISTER:
3432 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
3433 			idev = ipv6_add_dev(dev);
3434 			if (IS_ERR(idev))
3435 				return notifier_from_errno(PTR_ERR(idev));
3436 		}
3437 		break;
3438 
3439 	case NETDEV_CHANGEMTU:
3440 		/* if MTU under IPV6_MIN_MTU stop IPv6 on this interface. */
3441 		if (dev->mtu < IPV6_MIN_MTU) {
3442 			addrconf_ifdown(dev, dev != net->loopback_dev);
3443 			break;
3444 		}
3445 
3446 		if (idev) {
3447 			rt6_mtu_change(dev, dev->mtu);
3448 			idev->cnf.mtu6 = dev->mtu;
3449 			break;
3450 		}
3451 
3452 		/* allocate new idev */
3453 		idev = ipv6_add_dev(dev);
3454 		if (IS_ERR(idev))
3455 			break;
3456 
3457 		/* device is still not ready */
3458 		if (!(idev->if_flags & IF_READY))
3459 			break;
3460 
3461 		run_pending = 1;
3462 
3463 		/* fall through */
3464 
3465 	case NETDEV_UP:
3466 	case NETDEV_CHANGE:
3467 		if (dev->flags & IFF_SLAVE)
3468 			break;
3469 
3470 		if (idev && idev->cnf.disable_ipv6)
3471 			break;
3472 
3473 		if (event == NETDEV_UP) {
3474 			/* restore routes for permanent addresses */
3475 			addrconf_permanent_addr(net, dev);
3476 
3477 			if (!addrconf_link_ready(dev)) {
3478 				/* device is not ready yet. */
3479 				pr_info("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
3480 					dev->name);
3481 				break;
3482 			}
3483 
3484 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
3485 				idev = ipv6_add_dev(dev);
3486 
3487 			if (!IS_ERR_OR_NULL(idev)) {
3488 				idev->if_flags |= IF_READY;
3489 				run_pending = 1;
3490 			}
3491 		} else if (event == NETDEV_CHANGE) {
3492 			if (!addrconf_link_ready(dev)) {
3493 				/* device is still not ready. */
3494 				rt6_sync_down_dev(dev, event);
3495 				break;
3496 			}
3497 
3498 			if (idev) {
3499 				if (idev->if_flags & IF_READY) {
3500 					/* device is already configured -
3501 					 * but resend MLD reports, we might
3502 					 * have roamed and need to update
3503 					 * multicast snooping switches
3504 					 */
3505 					ipv6_mc_up(idev);
3506 					rt6_sync_up(dev, RTNH_F_LINKDOWN);
3507 					break;
3508 				}
3509 				idev->if_flags |= IF_READY;
3510 			}
3511 
3512 			pr_info("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
3513 				dev->name);
3514 
3515 			run_pending = 1;
3516 		}
3517 
3518 		switch (dev->type) {
3519 #if IS_ENABLED(CONFIG_IPV6_SIT)
3520 		case ARPHRD_SIT:
3521 			addrconf_sit_config(dev);
3522 			break;
3523 #endif
3524 #if IS_ENABLED(CONFIG_NET_IPGRE)
3525 		case ARPHRD_IPGRE:
3526 			addrconf_gre_config(dev);
3527 			break;
3528 #endif
3529 		case ARPHRD_LOOPBACK:
3530 			init_loopback(dev);
3531 			break;
3532 
3533 		default:
3534 			addrconf_dev_config(dev);
3535 			break;
3536 		}
3537 
3538 		if (!IS_ERR_OR_NULL(idev)) {
3539 			if (run_pending)
3540 				addrconf_dad_run(idev);
3541 
3542 			/* Device has an address by now */
3543 			rt6_sync_up(dev, RTNH_F_DEAD);
3544 
3545 			/*
3546 			 * If the MTU changed during the interface down,
3547 			 * when the interface up, the changed MTU must be
3548 			 * reflected in the idev as well as routers.
3549 			 */
3550 			if (idev->cnf.mtu6 != dev->mtu &&
3551 			    dev->mtu >= IPV6_MIN_MTU) {
3552 				rt6_mtu_change(dev, dev->mtu);
3553 				idev->cnf.mtu6 = dev->mtu;
3554 			}
3555 			idev->tstamp = jiffies;
3556 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
3557 
3558 			/*
3559 			 * If the changed mtu during down is lower than
3560 			 * IPV6_MIN_MTU stop IPv6 on this interface.
3561 			 */
3562 			if (dev->mtu < IPV6_MIN_MTU)
3563 				addrconf_ifdown(dev, dev != net->loopback_dev);
3564 		}
3565 		break;
3566 
3567 	case NETDEV_DOWN:
3568 	case NETDEV_UNREGISTER:
3569 		/*
3570 		 *	Remove all addresses from this interface.
3571 		 */
3572 		addrconf_ifdown(dev, event != NETDEV_DOWN);
3573 		break;
3574 
3575 	case NETDEV_CHANGENAME:
3576 		if (idev) {
3577 			snmp6_unregister_dev(idev);
3578 			addrconf_sysctl_unregister(idev);
3579 			err = addrconf_sysctl_register(idev);
3580 			if (err)
3581 				return notifier_from_errno(err);
3582 			err = snmp6_register_dev(idev);
3583 			if (err) {
3584 				addrconf_sysctl_unregister(idev);
3585 				return notifier_from_errno(err);
3586 			}
3587 		}
3588 		break;
3589 
3590 	case NETDEV_PRE_TYPE_CHANGE:
3591 	case NETDEV_POST_TYPE_CHANGE:
3592 		if (idev)
3593 			addrconf_type_change(dev, event);
3594 		break;
3595 
3596 	case NETDEV_CHANGEUPPER:
3597 		info = ptr;
3598 
3599 		/* flush all routes if dev is linked to or unlinked from
3600 		 * an L3 master device (e.g., VRF)
3601 		 */
3602 		if (info->upper_dev && netif_is_l3_master(info->upper_dev))
3603 			addrconf_ifdown(dev, 0);
3604 	}
3605 
3606 	return NOTIFY_OK;
3607 }
3608 
3609 /*
3610  *	addrconf module should be notified of a device going up
3611  */
3612 static struct notifier_block ipv6_dev_notf = {
3613 	.notifier_call = addrconf_notify,
3614 	.priority = ADDRCONF_NOTIFY_PRIORITY,
3615 };
3616 
3617 static void addrconf_type_change(struct net_device *dev, unsigned long event)
3618 {
3619 	struct inet6_dev *idev;
3620 	ASSERT_RTNL();
3621 
3622 	idev = __in6_dev_get(dev);
3623 
3624 	if (event == NETDEV_POST_TYPE_CHANGE)
3625 		ipv6_mc_remap(idev);
3626 	else if (event == NETDEV_PRE_TYPE_CHANGE)
3627 		ipv6_mc_unmap(idev);
3628 }
3629 
3630 static bool addr_is_local(const struct in6_addr *addr)
3631 {
3632 	return ipv6_addr_type(addr) &
3633 		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
3634 }
3635 
3636 static int addrconf_ifdown(struct net_device *dev, int how)
3637 {
3638 	unsigned long event = how ? NETDEV_UNREGISTER : NETDEV_DOWN;
3639 	struct net *net = dev_net(dev);
3640 	struct inet6_dev *idev;
3641 	struct inet6_ifaddr *ifa, *tmp;
3642 	bool keep_addr = false;
3643 	int state, i;
3644 
3645 	ASSERT_RTNL();
3646 
3647 	rt6_disable_ip(dev, event);
3648 
3649 	idev = __in6_dev_get(dev);
3650 	if (!idev)
3651 		return -ENODEV;
3652 
3653 	/*
3654 	 * Step 1: remove reference to ipv6 device from parent device.
3655 	 *	   Do not dev_put!
3656 	 */
3657 	if (how) {
3658 		idev->dead = 1;
3659 
3660 		/* protected by rtnl_lock */
3661 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
3662 
3663 		/* Step 1.5: remove snmp6 entry */
3664 		snmp6_unregister_dev(idev);
3665 
3666 	}
3667 
3668 	/* combine the user config with event to determine if permanent
3669 	 * addresses are to be removed from address hash table
3670 	 */
3671 	if (!how && !idev->cnf.disable_ipv6) {
3672 		/* aggregate the system setting and interface setting */
3673 		int _keep_addr = net->ipv6.devconf_all->keep_addr_on_down;
3674 
3675 		if (!_keep_addr)
3676 			_keep_addr = idev->cnf.keep_addr_on_down;
3677 
3678 		keep_addr = (_keep_addr > 0);
3679 	}
3680 
3681 	/* Step 2: clear hash table */
3682 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3683 		struct hlist_head *h = &inet6_addr_lst[i];
3684 
3685 		spin_lock_bh(&addrconf_hash_lock);
3686 restart:
3687 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
3688 			if (ifa->idev == idev) {
3689 				addrconf_del_dad_work(ifa);
3690 				/* combined flag + permanent flag decide if
3691 				 * address is retained on a down event
3692 				 */
3693 				if (!keep_addr ||
3694 				    !(ifa->flags & IFA_F_PERMANENT) ||
3695 				    addr_is_local(&ifa->addr)) {
3696 					hlist_del_init_rcu(&ifa->addr_lst);
3697 					goto restart;
3698 				}
3699 			}
3700 		}
3701 		spin_unlock_bh(&addrconf_hash_lock);
3702 	}
3703 
3704 	write_lock_bh(&idev->lock);
3705 
3706 	addrconf_del_rs_timer(idev);
3707 
3708 	/* Step 2: clear flags for stateless addrconf */
3709 	if (!how)
3710 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3711 
3712 	/* Step 3: clear tempaddr list */
3713 	while (!list_empty(&idev->tempaddr_list)) {
3714 		ifa = list_first_entry(&idev->tempaddr_list,
3715 				       struct inet6_ifaddr, tmp_list);
3716 		list_del(&ifa->tmp_list);
3717 		write_unlock_bh(&idev->lock);
3718 		spin_lock_bh(&ifa->lock);
3719 
3720 		if (ifa->ifpub) {
3721 			in6_ifa_put(ifa->ifpub);
3722 			ifa->ifpub = NULL;
3723 		}
3724 		spin_unlock_bh(&ifa->lock);
3725 		in6_ifa_put(ifa);
3726 		write_lock_bh(&idev->lock);
3727 	}
3728 
3729 	list_for_each_entry_safe(ifa, tmp, &idev->addr_list, if_list) {
3730 		struct fib6_info *rt = NULL;
3731 		bool keep;
3732 
3733 		addrconf_del_dad_work(ifa);
3734 
3735 		keep = keep_addr && (ifa->flags & IFA_F_PERMANENT) &&
3736 			!addr_is_local(&ifa->addr);
3737 
3738 		write_unlock_bh(&idev->lock);
3739 		spin_lock_bh(&ifa->lock);
3740 
3741 		if (keep) {
3742 			/* set state to skip the notifier below */
3743 			state = INET6_IFADDR_STATE_DEAD;
3744 			ifa->state = INET6_IFADDR_STATE_PREDAD;
3745 			if (!(ifa->flags & IFA_F_NODAD))
3746 				ifa->flags |= IFA_F_TENTATIVE;
3747 
3748 			rt = ifa->rt;
3749 			ifa->rt = NULL;
3750 		} else {
3751 			state = ifa->state;
3752 			ifa->state = INET6_IFADDR_STATE_DEAD;
3753 		}
3754 
3755 		spin_unlock_bh(&ifa->lock);
3756 
3757 		if (rt)
3758 			ip6_del_rt(net, rt);
3759 
3760 		if (state != INET6_IFADDR_STATE_DEAD) {
3761 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
3762 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
3763 		} else {
3764 			if (idev->cnf.forwarding)
3765 				addrconf_leave_anycast(ifa);
3766 			addrconf_leave_solict(ifa->idev, &ifa->addr);
3767 		}
3768 
3769 		write_lock_bh(&idev->lock);
3770 		if (!keep) {
3771 			list_del_rcu(&ifa->if_list);
3772 			in6_ifa_put(ifa);
3773 		}
3774 	}
3775 
3776 	write_unlock_bh(&idev->lock);
3777 
3778 	/* Step 5: Discard anycast and multicast list */
3779 	if (how) {
3780 		ipv6_ac_destroy_dev(idev);
3781 		ipv6_mc_destroy_dev(idev);
3782 	} else {
3783 		ipv6_mc_down(idev);
3784 	}
3785 
3786 	idev->tstamp = jiffies;
3787 
3788 	/* Last: Shot the device (if unregistered) */
3789 	if (how) {
3790 		addrconf_sysctl_unregister(idev);
3791 		neigh_parms_release(&nd_tbl, idev->nd_parms);
3792 		neigh_ifdown(&nd_tbl, dev);
3793 		in6_dev_put(idev);
3794 	}
3795 	return 0;
3796 }
3797 
3798 static void addrconf_rs_timer(struct timer_list *t)
3799 {
3800 	struct inet6_dev *idev = from_timer(idev, t, rs_timer);
3801 	struct net_device *dev = idev->dev;
3802 	struct in6_addr lladdr;
3803 
3804 	write_lock(&idev->lock);
3805 	if (idev->dead || !(idev->if_flags & IF_READY))
3806 		goto out;
3807 
3808 	if (!ipv6_accept_ra(idev))
3809 		goto out;
3810 
3811 	/* Announcement received after solicitation was sent */
3812 	if (idev->if_flags & IF_RA_RCVD)
3813 		goto out;
3814 
3815 	if (idev->rs_probes++ < idev->cnf.rtr_solicits || idev->cnf.rtr_solicits < 0) {
3816 		write_unlock(&idev->lock);
3817 		if (!ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
3818 			ndisc_send_rs(dev, &lladdr,
3819 				      &in6addr_linklocal_allrouters);
3820 		else
3821 			goto put;
3822 
3823 		write_lock(&idev->lock);
3824 		idev->rs_interval = rfc3315_s14_backoff_update(
3825 			idev->rs_interval, idev->cnf.rtr_solicit_max_interval);
3826 		/* The wait after the last probe can be shorter */
3827 		addrconf_mod_rs_timer(idev, (idev->rs_probes ==
3828 					     idev->cnf.rtr_solicits) ?
3829 				      idev->cnf.rtr_solicit_delay :
3830 				      idev->rs_interval);
3831 	} else {
3832 		/*
3833 		 * Note: we do not support deprecated "all on-link"
3834 		 * assumption any longer.
3835 		 */
3836 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
3837 	}
3838 
3839 out:
3840 	write_unlock(&idev->lock);
3841 put:
3842 	in6_dev_put(idev);
3843 }
3844 
3845 /*
3846  *	Duplicate Address Detection
3847  */
3848 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
3849 {
3850 	unsigned long rand_num;
3851 	struct inet6_dev *idev = ifp->idev;
3852 	u64 nonce;
3853 
3854 	if (ifp->flags & IFA_F_OPTIMISTIC)
3855 		rand_num = 0;
3856 	else
3857 		rand_num = prandom_u32() % (idev->cnf.rtr_solicit_delay ? : 1);
3858 
3859 	nonce = 0;
3860 	if (idev->cnf.enhanced_dad ||
3861 	    dev_net(idev->dev)->ipv6.devconf_all->enhanced_dad) {
3862 		do
3863 			get_random_bytes(&nonce, 6);
3864 		while (nonce == 0);
3865 	}
3866 	ifp->dad_nonce = nonce;
3867 	ifp->dad_probes = idev->cnf.dad_transmits;
3868 	addrconf_mod_dad_work(ifp, rand_num);
3869 }
3870 
3871 static void addrconf_dad_begin(struct inet6_ifaddr *ifp)
3872 {
3873 	struct inet6_dev *idev = ifp->idev;
3874 	struct net_device *dev = idev->dev;
3875 	bool bump_id, notify = false;
3876 	struct net *net;
3877 
3878 	addrconf_join_solict(dev, &ifp->addr);
3879 
3880 	prandom_seed((__force u32) ifp->addr.s6_addr32[3]);
3881 
3882 	read_lock_bh(&idev->lock);
3883 	spin_lock(&ifp->lock);
3884 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
3885 		goto out;
3886 
3887 	net = dev_net(dev);
3888 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
3889 	    (net->ipv6.devconf_all->accept_dad < 1 &&
3890 	     idev->cnf.accept_dad < 1) ||
3891 	    !(ifp->flags&IFA_F_TENTATIVE) ||
3892 	    ifp->flags & IFA_F_NODAD) {
3893 		bool send_na = false;
3894 
3895 		if (ifp->flags & IFA_F_TENTATIVE &&
3896 		    !(ifp->flags & IFA_F_OPTIMISTIC))
3897 			send_na = true;
3898 		bump_id = ifp->flags & IFA_F_TENTATIVE;
3899 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3900 		spin_unlock(&ifp->lock);
3901 		read_unlock_bh(&idev->lock);
3902 
3903 		addrconf_dad_completed(ifp, bump_id, send_na);
3904 		return;
3905 	}
3906 
3907 	if (!(idev->if_flags & IF_READY)) {
3908 		spin_unlock(&ifp->lock);
3909 		read_unlock_bh(&idev->lock);
3910 		/*
3911 		 * If the device is not ready:
3912 		 * - keep it tentative if it is a permanent address.
3913 		 * - otherwise, kill it.
3914 		 */
3915 		in6_ifa_hold(ifp);
3916 		addrconf_dad_stop(ifp, 0);
3917 		return;
3918 	}
3919 
3920 	/*
3921 	 * Optimistic nodes can start receiving
3922 	 * Frames right away
3923 	 */
3924 	if (ifp->flags & IFA_F_OPTIMISTIC) {
3925 		ip6_ins_rt(net, ifp->rt);
3926 		if (ipv6_use_optimistic_addr(net, idev)) {
3927 			/* Because optimistic nodes can use this address,
3928 			 * notify listeners. If DAD fails, RTM_DELADDR is sent.
3929 			 */
3930 			notify = true;
3931 		}
3932 	}
3933 
3934 	addrconf_dad_kick(ifp);
3935 out:
3936 	spin_unlock(&ifp->lock);
3937 	read_unlock_bh(&idev->lock);
3938 	if (notify)
3939 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3940 }
3941 
3942 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
3943 {
3944 	bool begin_dad = false;
3945 
3946 	spin_lock_bh(&ifp->lock);
3947 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
3948 		ifp->state = INET6_IFADDR_STATE_PREDAD;
3949 		begin_dad = true;
3950 	}
3951 	spin_unlock_bh(&ifp->lock);
3952 
3953 	if (begin_dad)
3954 		addrconf_mod_dad_work(ifp, 0);
3955 }
3956 
3957 static void addrconf_dad_work(struct work_struct *w)
3958 {
3959 	struct inet6_ifaddr *ifp = container_of(to_delayed_work(w),
3960 						struct inet6_ifaddr,
3961 						dad_work);
3962 	struct inet6_dev *idev = ifp->idev;
3963 	bool bump_id, disable_ipv6 = false;
3964 	struct in6_addr mcaddr;
3965 
3966 	enum {
3967 		DAD_PROCESS,
3968 		DAD_BEGIN,
3969 		DAD_ABORT,
3970 	} action = DAD_PROCESS;
3971 
3972 	rtnl_lock();
3973 
3974 	spin_lock_bh(&ifp->lock);
3975 	if (ifp->state == INET6_IFADDR_STATE_PREDAD) {
3976 		action = DAD_BEGIN;
3977 		ifp->state = INET6_IFADDR_STATE_DAD;
3978 	} else if (ifp->state == INET6_IFADDR_STATE_ERRDAD) {
3979 		action = DAD_ABORT;
3980 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
3981 
3982 		if ((dev_net(idev->dev)->ipv6.devconf_all->accept_dad > 1 ||
3983 		     idev->cnf.accept_dad > 1) &&
3984 		    !idev->cnf.disable_ipv6 &&
3985 		    !(ifp->flags & IFA_F_STABLE_PRIVACY)) {
3986 			struct in6_addr addr;
3987 
3988 			addr.s6_addr32[0] = htonl(0xfe800000);
3989 			addr.s6_addr32[1] = 0;
3990 
3991 			if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
3992 			    ipv6_addr_equal(&ifp->addr, &addr)) {
3993 				/* DAD failed for link-local based on MAC */
3994 				idev->cnf.disable_ipv6 = 1;
3995 
3996 				pr_info("%s: IPv6 being disabled!\n",
3997 					ifp->idev->dev->name);
3998 				disable_ipv6 = true;
3999 			}
4000 		}
4001 	}
4002 	spin_unlock_bh(&ifp->lock);
4003 
4004 	if (action == DAD_BEGIN) {
4005 		addrconf_dad_begin(ifp);
4006 		goto out;
4007 	} else if (action == DAD_ABORT) {
4008 		in6_ifa_hold(ifp);
4009 		addrconf_dad_stop(ifp, 1);
4010 		if (disable_ipv6)
4011 			addrconf_ifdown(idev->dev, 0);
4012 		goto out;
4013 	}
4014 
4015 	if (!ifp->dad_probes && addrconf_dad_end(ifp))
4016 		goto out;
4017 
4018 	write_lock_bh(&idev->lock);
4019 	if (idev->dead || !(idev->if_flags & IF_READY)) {
4020 		write_unlock_bh(&idev->lock);
4021 		goto out;
4022 	}
4023 
4024 	spin_lock(&ifp->lock);
4025 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
4026 		spin_unlock(&ifp->lock);
4027 		write_unlock_bh(&idev->lock);
4028 		goto out;
4029 	}
4030 
4031 	if (ifp->dad_probes == 0) {
4032 		bool send_na = false;
4033 
4034 		/*
4035 		 * DAD was successful
4036 		 */
4037 
4038 		if (ifp->flags & IFA_F_TENTATIVE &&
4039 		    !(ifp->flags & IFA_F_OPTIMISTIC))
4040 			send_na = true;
4041 		bump_id = ifp->flags & IFA_F_TENTATIVE;
4042 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
4043 		spin_unlock(&ifp->lock);
4044 		write_unlock_bh(&idev->lock);
4045 
4046 		addrconf_dad_completed(ifp, bump_id, send_na);
4047 
4048 		goto out;
4049 	}
4050 
4051 	ifp->dad_probes--;
4052 	addrconf_mod_dad_work(ifp,
4053 			      NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME));
4054 	spin_unlock(&ifp->lock);
4055 	write_unlock_bh(&idev->lock);
4056 
4057 	/* send a neighbour solicitation for our addr */
4058 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
4059 	ndisc_send_ns(ifp->idev->dev, &ifp->addr, &mcaddr, &in6addr_any,
4060 		      ifp->dad_nonce);
4061 out:
4062 	in6_ifa_put(ifp);
4063 	rtnl_unlock();
4064 }
4065 
4066 /* ifp->idev must be at least read locked */
4067 static bool ipv6_lonely_lladdr(struct inet6_ifaddr *ifp)
4068 {
4069 	struct inet6_ifaddr *ifpiter;
4070 	struct inet6_dev *idev = ifp->idev;
4071 
4072 	list_for_each_entry_reverse(ifpiter, &idev->addr_list, if_list) {
4073 		if (ifpiter->scope > IFA_LINK)
4074 			break;
4075 		if (ifp != ifpiter && ifpiter->scope == IFA_LINK &&
4076 		    (ifpiter->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE|
4077 				       IFA_F_OPTIMISTIC|IFA_F_DADFAILED)) ==
4078 		    IFA_F_PERMANENT)
4079 			return false;
4080 	}
4081 	return true;
4082 }
4083 
4084 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
4085 				   bool send_na)
4086 {
4087 	struct net_device *dev = ifp->idev->dev;
4088 	struct in6_addr lladdr;
4089 	bool send_rs, send_mld;
4090 
4091 	addrconf_del_dad_work(ifp);
4092 
4093 	/*
4094 	 *	Configure the address for reception. Now it is valid.
4095 	 */
4096 
4097 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
4098 
4099 	/* If added prefix is link local and we are prepared to process
4100 	   router advertisements, start sending router solicitations.
4101 	 */
4102 
4103 	read_lock_bh(&ifp->idev->lock);
4104 	send_mld = ifp->scope == IFA_LINK && ipv6_lonely_lladdr(ifp);
4105 	send_rs = send_mld &&
4106 		  ipv6_accept_ra(ifp->idev) &&
4107 		  ifp->idev->cnf.rtr_solicits != 0 &&
4108 		  (dev->flags&IFF_LOOPBACK) == 0;
4109 	read_unlock_bh(&ifp->idev->lock);
4110 
4111 	/* While dad is in progress mld report's source address is in6_addrany.
4112 	 * Resend with proper ll now.
4113 	 */
4114 	if (send_mld)
4115 		ipv6_mc_dad_complete(ifp->idev);
4116 
4117 	/* send unsolicited NA if enabled */
4118 	if (send_na &&
4119 	    (ifp->idev->cnf.ndisc_notify ||
4120 	     dev_net(dev)->ipv6.devconf_all->ndisc_notify)) {
4121 		ndisc_send_na(dev, &in6addr_linklocal_allnodes, &ifp->addr,
4122 			      /*router=*/ !!ifp->idev->cnf.forwarding,
4123 			      /*solicited=*/ false, /*override=*/ true,
4124 			      /*inc_opt=*/ true);
4125 	}
4126 
4127 	if (send_rs) {
4128 		/*
4129 		 *	If a host as already performed a random delay
4130 		 *	[...] as part of DAD [...] there is no need
4131 		 *	to delay again before sending the first RS
4132 		 */
4133 		if (ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4134 			return;
4135 		ndisc_send_rs(dev, &lladdr, &in6addr_linklocal_allrouters);
4136 
4137 		write_lock_bh(&ifp->idev->lock);
4138 		spin_lock(&ifp->lock);
4139 		ifp->idev->rs_interval = rfc3315_s14_backoff_init(
4140 			ifp->idev->cnf.rtr_solicit_interval);
4141 		ifp->idev->rs_probes = 1;
4142 		ifp->idev->if_flags |= IF_RS_SENT;
4143 		addrconf_mod_rs_timer(ifp->idev, ifp->idev->rs_interval);
4144 		spin_unlock(&ifp->lock);
4145 		write_unlock_bh(&ifp->idev->lock);
4146 	}
4147 
4148 	if (bump_id)
4149 		rt_genid_bump_ipv6(dev_net(dev));
4150 
4151 	/* Make sure that a new temporary address will be created
4152 	 * before this temporary address becomes deprecated.
4153 	 */
4154 	if (ifp->flags & IFA_F_TEMPORARY)
4155 		addrconf_verify_rtnl();
4156 }
4157 
4158 static void addrconf_dad_run(struct inet6_dev *idev)
4159 {
4160 	struct inet6_ifaddr *ifp;
4161 
4162 	read_lock_bh(&idev->lock);
4163 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
4164 		spin_lock(&ifp->lock);
4165 		if (ifp->flags & IFA_F_TENTATIVE &&
4166 		    ifp->state == INET6_IFADDR_STATE_DAD)
4167 			addrconf_dad_kick(ifp);
4168 		spin_unlock(&ifp->lock);
4169 	}
4170 	read_unlock_bh(&idev->lock);
4171 }
4172 
4173 #ifdef CONFIG_PROC_FS
4174 struct if6_iter_state {
4175 	struct seq_net_private p;
4176 	int bucket;
4177 	int offset;
4178 };
4179 
4180 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
4181 {
4182 	struct if6_iter_state *state = seq->private;
4183 	struct net *net = seq_file_net(seq);
4184 	struct inet6_ifaddr *ifa = NULL;
4185 	int p = 0;
4186 
4187 	/* initial bucket if pos is 0 */
4188 	if (pos == 0) {
4189 		state->bucket = 0;
4190 		state->offset = 0;
4191 	}
4192 
4193 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
4194 		hlist_for_each_entry_rcu(ifa, &inet6_addr_lst[state->bucket],
4195 					 addr_lst) {
4196 			if (!net_eq(dev_net(ifa->idev->dev), net))
4197 				continue;
4198 			/* sync with offset */
4199 			if (p < state->offset) {
4200 				p++;
4201 				continue;
4202 			}
4203 			state->offset++;
4204 			return ifa;
4205 		}
4206 
4207 		/* prepare for next bucket */
4208 		state->offset = 0;
4209 		p = 0;
4210 	}
4211 	return NULL;
4212 }
4213 
4214 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
4215 					 struct inet6_ifaddr *ifa)
4216 {
4217 	struct if6_iter_state *state = seq->private;
4218 	struct net *net = seq_file_net(seq);
4219 
4220 	hlist_for_each_entry_continue_rcu(ifa, addr_lst) {
4221 		if (!net_eq(dev_net(ifa->idev->dev), net))
4222 			continue;
4223 		state->offset++;
4224 		return ifa;
4225 	}
4226 
4227 	while (++state->bucket < IN6_ADDR_HSIZE) {
4228 		state->offset = 0;
4229 		hlist_for_each_entry_rcu(ifa,
4230 				     &inet6_addr_lst[state->bucket], addr_lst) {
4231 			if (!net_eq(dev_net(ifa->idev->dev), net))
4232 				continue;
4233 			state->offset++;
4234 			return ifa;
4235 		}
4236 	}
4237 
4238 	return NULL;
4239 }
4240 
4241 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
4242 	__acquires(rcu)
4243 {
4244 	rcu_read_lock();
4245 	return if6_get_first(seq, *pos);
4246 }
4247 
4248 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4249 {
4250 	struct inet6_ifaddr *ifa;
4251 
4252 	ifa = if6_get_next(seq, v);
4253 	++*pos;
4254 	return ifa;
4255 }
4256 
4257 static void if6_seq_stop(struct seq_file *seq, void *v)
4258 	__releases(rcu)
4259 {
4260 	rcu_read_unlock();
4261 }
4262 
4263 static int if6_seq_show(struct seq_file *seq, void *v)
4264 {
4265 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
4266 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
4267 		   &ifp->addr,
4268 		   ifp->idev->dev->ifindex,
4269 		   ifp->prefix_len,
4270 		   ifp->scope,
4271 		   (u8) ifp->flags,
4272 		   ifp->idev->dev->name);
4273 	return 0;
4274 }
4275 
4276 static const struct seq_operations if6_seq_ops = {
4277 	.start	= if6_seq_start,
4278 	.next	= if6_seq_next,
4279 	.show	= if6_seq_show,
4280 	.stop	= if6_seq_stop,
4281 };
4282 
4283 static int __net_init if6_proc_net_init(struct net *net)
4284 {
4285 	if (!proc_create_net("if_inet6", 0444, net->proc_net, &if6_seq_ops,
4286 			sizeof(struct if6_iter_state)))
4287 		return -ENOMEM;
4288 	return 0;
4289 }
4290 
4291 static void __net_exit if6_proc_net_exit(struct net *net)
4292 {
4293 	remove_proc_entry("if_inet6", net->proc_net);
4294 }
4295 
4296 static struct pernet_operations if6_proc_net_ops = {
4297 	.init = if6_proc_net_init,
4298 	.exit = if6_proc_net_exit,
4299 };
4300 
4301 int __init if6_proc_init(void)
4302 {
4303 	return register_pernet_subsys(&if6_proc_net_ops);
4304 }
4305 
4306 void if6_proc_exit(void)
4307 {
4308 	unregister_pernet_subsys(&if6_proc_net_ops);
4309 }
4310 #endif	/* CONFIG_PROC_FS */
4311 
4312 #if IS_ENABLED(CONFIG_IPV6_MIP6)
4313 /* Check if address is a home address configured on any interface. */
4314 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
4315 {
4316 	unsigned int hash = inet6_addr_hash(net, addr);
4317 	struct inet6_ifaddr *ifp = NULL;
4318 	int ret = 0;
4319 
4320 	rcu_read_lock();
4321 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
4322 		if (!net_eq(dev_net(ifp->idev->dev), net))
4323 			continue;
4324 		if (ipv6_addr_equal(&ifp->addr, addr) &&
4325 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
4326 			ret = 1;
4327 			break;
4328 		}
4329 	}
4330 	rcu_read_unlock();
4331 	return ret;
4332 }
4333 #endif
4334 
4335 /*
4336  *	Periodic address status verification
4337  */
4338 
4339 static void addrconf_verify_rtnl(void)
4340 {
4341 	unsigned long now, next, next_sec, next_sched;
4342 	struct inet6_ifaddr *ifp;
4343 	int i;
4344 
4345 	ASSERT_RTNL();
4346 
4347 	rcu_read_lock_bh();
4348 	now = jiffies;
4349 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
4350 
4351 	cancel_delayed_work(&addr_chk_work);
4352 
4353 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
4354 restart:
4355 		hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[i], addr_lst) {
4356 			unsigned long age;
4357 
4358 			/* When setting preferred_lft to a value not zero or
4359 			 * infinity, while valid_lft is infinity
4360 			 * IFA_F_PERMANENT has a non-infinity life time.
4361 			 */
4362 			if ((ifp->flags & IFA_F_PERMANENT) &&
4363 			    (ifp->prefered_lft == INFINITY_LIFE_TIME))
4364 				continue;
4365 
4366 			spin_lock(&ifp->lock);
4367 			/* We try to batch several events at once. */
4368 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
4369 
4370 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
4371 			    age >= ifp->valid_lft) {
4372 				spin_unlock(&ifp->lock);
4373 				in6_ifa_hold(ifp);
4374 				ipv6_del_addr(ifp);
4375 				goto restart;
4376 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
4377 				spin_unlock(&ifp->lock);
4378 				continue;
4379 			} else if (age >= ifp->prefered_lft) {
4380 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
4381 				int deprecate = 0;
4382 
4383 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
4384 					deprecate = 1;
4385 					ifp->flags |= IFA_F_DEPRECATED;
4386 				}
4387 
4388 				if ((ifp->valid_lft != INFINITY_LIFE_TIME) &&
4389 				    (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)))
4390 					next = ifp->tstamp + ifp->valid_lft * HZ;
4391 
4392 				spin_unlock(&ifp->lock);
4393 
4394 				if (deprecate) {
4395 					in6_ifa_hold(ifp);
4396 
4397 					ipv6_ifa_notify(0, ifp);
4398 					in6_ifa_put(ifp);
4399 					goto restart;
4400 				}
4401 			} else if ((ifp->flags&IFA_F_TEMPORARY) &&
4402 				   !(ifp->flags&IFA_F_TENTATIVE)) {
4403 				unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
4404 					ifp->idev->cnf.dad_transmits *
4405 					NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME) / HZ;
4406 
4407 				if (age >= ifp->prefered_lft - regen_advance) {
4408 					struct inet6_ifaddr *ifpub = ifp->ifpub;
4409 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4410 						next = ifp->tstamp + ifp->prefered_lft * HZ;
4411 					if (!ifp->regen_count && ifpub) {
4412 						ifp->regen_count++;
4413 						in6_ifa_hold(ifp);
4414 						in6_ifa_hold(ifpub);
4415 						spin_unlock(&ifp->lock);
4416 
4417 						spin_lock(&ifpub->lock);
4418 						ifpub->regen_count = 0;
4419 						spin_unlock(&ifpub->lock);
4420 						rcu_read_unlock_bh();
4421 						ipv6_create_tempaddr(ifpub, ifp, true);
4422 						in6_ifa_put(ifpub);
4423 						in6_ifa_put(ifp);
4424 						rcu_read_lock_bh();
4425 						goto restart;
4426 					}
4427 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
4428 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
4429 				spin_unlock(&ifp->lock);
4430 			} else {
4431 				/* ifp->prefered_lft <= ifp->valid_lft */
4432 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4433 					next = ifp->tstamp + ifp->prefered_lft * HZ;
4434 				spin_unlock(&ifp->lock);
4435 			}
4436 		}
4437 	}
4438 
4439 	next_sec = round_jiffies_up(next);
4440 	next_sched = next;
4441 
4442 	/* If rounded timeout is accurate enough, accept it. */
4443 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
4444 		next_sched = next_sec;
4445 
4446 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
4447 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
4448 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
4449 
4450 	pr_debug("now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
4451 		 now, next, next_sec, next_sched);
4452 	mod_delayed_work(addrconf_wq, &addr_chk_work, next_sched - now);
4453 	rcu_read_unlock_bh();
4454 }
4455 
4456 static void addrconf_verify_work(struct work_struct *w)
4457 {
4458 	rtnl_lock();
4459 	addrconf_verify_rtnl();
4460 	rtnl_unlock();
4461 }
4462 
4463 static void addrconf_verify(void)
4464 {
4465 	mod_delayed_work(addrconf_wq, &addr_chk_work, 0);
4466 }
4467 
4468 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
4469 				     struct in6_addr **peer_pfx)
4470 {
4471 	struct in6_addr *pfx = NULL;
4472 
4473 	*peer_pfx = NULL;
4474 
4475 	if (addr)
4476 		pfx = nla_data(addr);
4477 
4478 	if (local) {
4479 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
4480 			*peer_pfx = pfx;
4481 		pfx = nla_data(local);
4482 	}
4483 
4484 	return pfx;
4485 }
4486 
4487 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
4488 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
4489 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
4490 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
4491 	[IFA_FLAGS]		= { .len = sizeof(u32) },
4492 	[IFA_RT_PRIORITY]	= { .len = sizeof(u32) },
4493 };
4494 
4495 static int
4496 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh,
4497 		  struct netlink_ext_ack *extack)
4498 {
4499 	struct net *net = sock_net(skb->sk);
4500 	struct ifaddrmsg *ifm;
4501 	struct nlattr *tb[IFA_MAX+1];
4502 	struct in6_addr *pfx, *peer_pfx;
4503 	u32 ifa_flags;
4504 	int err;
4505 
4506 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy,
4507 			  extack);
4508 	if (err < 0)
4509 		return err;
4510 
4511 	ifm = nlmsg_data(nlh);
4512 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4513 	if (!pfx)
4514 		return -EINVAL;
4515 
4516 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
4517 
4518 	/* We ignore other flags so far. */
4519 	ifa_flags &= IFA_F_MANAGETEMPADDR;
4520 
4521 	return inet6_addr_del(net, ifm->ifa_index, ifa_flags, pfx,
4522 			      ifm->ifa_prefixlen);
4523 }
4524 
4525 static int modify_prefix_route(struct inet6_ifaddr *ifp,
4526 			       unsigned long expires, u32 flags)
4527 {
4528 	struct fib6_info *f6i;
4529 	u32 prio;
4530 
4531 	f6i = addrconf_get_prefix_route(&ifp->addr,
4532 					ifp->prefix_len,
4533 					ifp->idev->dev,
4534 					0, RTF_GATEWAY | RTF_DEFAULT);
4535 	if (!f6i)
4536 		return -ENOENT;
4537 
4538 	prio = ifp->rt_priority ? : IP6_RT_PRIO_ADDRCONF;
4539 	if (f6i->fib6_metric != prio) {
4540 		/* delete old one */
4541 		ip6_del_rt(dev_net(ifp->idev->dev), f6i);
4542 
4543 		/* add new one */
4544 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
4545 				      ifp->rt_priority, ifp->idev->dev,
4546 				      expires, flags, GFP_KERNEL);
4547 	} else {
4548 		if (!expires)
4549 			fib6_clean_expires(f6i);
4550 		else
4551 			fib6_set_expires(f6i, expires);
4552 
4553 		fib6_info_release(f6i);
4554 	}
4555 
4556 	return 0;
4557 }
4558 
4559 static int inet6_addr_modify(struct inet6_ifaddr *ifp, struct ifa6_config *cfg)
4560 {
4561 	u32 flags;
4562 	clock_t expires;
4563 	unsigned long timeout;
4564 	bool was_managetempaddr;
4565 	bool had_prefixroute;
4566 
4567 	ASSERT_RTNL();
4568 
4569 	if (!cfg->valid_lft || cfg->preferred_lft > cfg->valid_lft)
4570 		return -EINVAL;
4571 
4572 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR &&
4573 	    (ifp->flags & IFA_F_TEMPORARY || ifp->prefix_len != 64))
4574 		return -EINVAL;
4575 
4576 	if (!(ifp->flags & IFA_F_TENTATIVE) || ifp->flags & IFA_F_DADFAILED)
4577 		cfg->ifa_flags &= ~IFA_F_OPTIMISTIC;
4578 
4579 	timeout = addrconf_timeout_fixup(cfg->valid_lft, HZ);
4580 	if (addrconf_finite_timeout(timeout)) {
4581 		expires = jiffies_to_clock_t(timeout * HZ);
4582 		cfg->valid_lft = timeout;
4583 		flags = RTF_EXPIRES;
4584 	} else {
4585 		expires = 0;
4586 		flags = 0;
4587 		cfg->ifa_flags |= IFA_F_PERMANENT;
4588 	}
4589 
4590 	timeout = addrconf_timeout_fixup(cfg->preferred_lft, HZ);
4591 	if (addrconf_finite_timeout(timeout)) {
4592 		if (timeout == 0)
4593 			cfg->ifa_flags |= IFA_F_DEPRECATED;
4594 		cfg->preferred_lft = timeout;
4595 	}
4596 
4597 	spin_lock_bh(&ifp->lock);
4598 	was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;
4599 	had_prefixroute = ifp->flags & IFA_F_PERMANENT &&
4600 			  !(ifp->flags & IFA_F_NOPREFIXROUTE);
4601 	ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |
4602 			IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4603 			IFA_F_NOPREFIXROUTE);
4604 	ifp->flags |= cfg->ifa_flags;
4605 	ifp->tstamp = jiffies;
4606 	ifp->valid_lft = cfg->valid_lft;
4607 	ifp->prefered_lft = cfg->preferred_lft;
4608 
4609 	if (cfg->rt_priority && cfg->rt_priority != ifp->rt_priority)
4610 		ifp->rt_priority = cfg->rt_priority;
4611 
4612 	spin_unlock_bh(&ifp->lock);
4613 	if (!(ifp->flags&IFA_F_TENTATIVE))
4614 		ipv6_ifa_notify(0, ifp);
4615 
4616 	if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
4617 		int rc = -ENOENT;
4618 
4619 		if (had_prefixroute)
4620 			rc = modify_prefix_route(ifp, expires, flags);
4621 
4622 		/* prefix route could have been deleted; if so restore it */
4623 		if (rc == -ENOENT) {
4624 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
4625 					      ifp->rt_priority, ifp->idev->dev,
4626 					      expires, flags, GFP_KERNEL);
4627 		}
4628 	} else if (had_prefixroute) {
4629 		enum cleanup_prefix_rt_t action;
4630 		unsigned long rt_expires;
4631 
4632 		write_lock_bh(&ifp->idev->lock);
4633 		action = check_cleanup_prefix_route(ifp, &rt_expires);
4634 		write_unlock_bh(&ifp->idev->lock);
4635 
4636 		if (action != CLEANUP_PREFIX_RT_NOP) {
4637 			cleanup_prefix_route(ifp, rt_expires,
4638 				action == CLEANUP_PREFIX_RT_DEL);
4639 		}
4640 	}
4641 
4642 	if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {
4643 		if (was_managetempaddr &&
4644 		    !(ifp->flags & IFA_F_MANAGETEMPADDR)) {
4645 			cfg->valid_lft = 0;
4646 			cfg->preferred_lft = 0;
4647 		}
4648 		manage_tempaddrs(ifp->idev, ifp, cfg->valid_lft,
4649 				 cfg->preferred_lft, !was_managetempaddr,
4650 				 jiffies);
4651 	}
4652 
4653 	addrconf_verify_rtnl();
4654 
4655 	return 0;
4656 }
4657 
4658 static int
4659 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
4660 		  struct netlink_ext_ack *extack)
4661 {
4662 	struct net *net = sock_net(skb->sk);
4663 	struct ifaddrmsg *ifm;
4664 	struct nlattr *tb[IFA_MAX+1];
4665 	struct in6_addr *peer_pfx;
4666 	struct inet6_ifaddr *ifa;
4667 	struct net_device *dev;
4668 	struct inet6_dev *idev;
4669 	struct ifa6_config cfg;
4670 	int err;
4671 
4672 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy,
4673 			  extack);
4674 	if (err < 0)
4675 		return err;
4676 
4677 	memset(&cfg, 0, sizeof(cfg));
4678 
4679 	ifm = nlmsg_data(nlh);
4680 	cfg.pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4681 	if (!cfg.pfx)
4682 		return -EINVAL;
4683 
4684 	cfg.peer_pfx = peer_pfx;
4685 	cfg.plen = ifm->ifa_prefixlen;
4686 	if (tb[IFA_RT_PRIORITY])
4687 		cfg.rt_priority = nla_get_u32(tb[IFA_RT_PRIORITY]);
4688 
4689 	cfg.valid_lft = INFINITY_LIFE_TIME;
4690 	cfg.preferred_lft = INFINITY_LIFE_TIME;
4691 
4692 	if (tb[IFA_CACHEINFO]) {
4693 		struct ifa_cacheinfo *ci;
4694 
4695 		ci = nla_data(tb[IFA_CACHEINFO]);
4696 		cfg.valid_lft = ci->ifa_valid;
4697 		cfg.preferred_lft = ci->ifa_prefered;
4698 	}
4699 
4700 	dev =  __dev_get_by_index(net, ifm->ifa_index);
4701 	if (!dev)
4702 		return -ENODEV;
4703 
4704 	if (tb[IFA_FLAGS])
4705 		cfg.ifa_flags = nla_get_u32(tb[IFA_FLAGS]);
4706 	else
4707 		cfg.ifa_flags = ifm->ifa_flags;
4708 
4709 	/* We ignore other flags so far. */
4710 	cfg.ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS |
4711 			 IFA_F_MANAGETEMPADDR | IFA_F_NOPREFIXROUTE |
4712 			 IFA_F_MCAUTOJOIN | IFA_F_OPTIMISTIC;
4713 
4714 	idev = ipv6_find_idev(dev);
4715 	if (IS_ERR(idev))
4716 		return PTR_ERR(idev);
4717 
4718 	if (!ipv6_allow_optimistic_dad(net, idev))
4719 		cfg.ifa_flags &= ~IFA_F_OPTIMISTIC;
4720 
4721 	if (cfg.ifa_flags & IFA_F_NODAD &&
4722 	    cfg.ifa_flags & IFA_F_OPTIMISTIC) {
4723 		NL_SET_ERR_MSG(extack, "IFA_F_NODAD and IFA_F_OPTIMISTIC are mutually exclusive");
4724 		return -EINVAL;
4725 	}
4726 
4727 	ifa = ipv6_get_ifaddr(net, cfg.pfx, dev, 1);
4728 	if (!ifa) {
4729 		/*
4730 		 * It would be best to check for !NLM_F_CREATE here but
4731 		 * userspace already relies on not having to provide this.
4732 		 */
4733 		return inet6_addr_add(net, ifm->ifa_index, &cfg, extack);
4734 	}
4735 
4736 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
4737 	    !(nlh->nlmsg_flags & NLM_F_REPLACE))
4738 		err = -EEXIST;
4739 	else
4740 		err = inet6_addr_modify(ifa, &cfg);
4741 
4742 	in6_ifa_put(ifa);
4743 
4744 	return err;
4745 }
4746 
4747 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u32 flags,
4748 			  u8 scope, int ifindex)
4749 {
4750 	struct ifaddrmsg *ifm;
4751 
4752 	ifm = nlmsg_data(nlh);
4753 	ifm->ifa_family = AF_INET6;
4754 	ifm->ifa_prefixlen = prefixlen;
4755 	ifm->ifa_flags = flags;
4756 	ifm->ifa_scope = scope;
4757 	ifm->ifa_index = ifindex;
4758 }
4759 
4760 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
4761 			 unsigned long tstamp, u32 preferred, u32 valid)
4762 {
4763 	struct ifa_cacheinfo ci;
4764 
4765 	ci.cstamp = cstamp_delta(cstamp);
4766 	ci.tstamp = cstamp_delta(tstamp);
4767 	ci.ifa_prefered = preferred;
4768 	ci.ifa_valid = valid;
4769 
4770 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
4771 }
4772 
4773 static inline int rt_scope(int ifa_scope)
4774 {
4775 	if (ifa_scope & IFA_HOST)
4776 		return RT_SCOPE_HOST;
4777 	else if (ifa_scope & IFA_LINK)
4778 		return RT_SCOPE_LINK;
4779 	else if (ifa_scope & IFA_SITE)
4780 		return RT_SCOPE_SITE;
4781 	else
4782 		return RT_SCOPE_UNIVERSE;
4783 }
4784 
4785 static inline int inet6_ifaddr_msgsize(void)
4786 {
4787 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
4788 	       + nla_total_size(16) /* IFA_LOCAL */
4789 	       + nla_total_size(16) /* IFA_ADDRESS */
4790 	       + nla_total_size(sizeof(struct ifa_cacheinfo))
4791 	       + nla_total_size(4)  /* IFA_FLAGS */
4792 	       + nla_total_size(4)  /* IFA_RT_PRIORITY */;
4793 }
4794 
4795 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
4796 			     u32 portid, u32 seq, int event, unsigned int flags)
4797 {
4798 	struct nlmsghdr  *nlh;
4799 	u32 preferred, valid;
4800 
4801 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4802 	if (!nlh)
4803 		return -EMSGSIZE;
4804 
4805 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
4806 		      ifa->idev->dev->ifindex);
4807 
4808 	if (!((ifa->flags&IFA_F_PERMANENT) &&
4809 	      (ifa->prefered_lft == INFINITY_LIFE_TIME))) {
4810 		preferred = ifa->prefered_lft;
4811 		valid = ifa->valid_lft;
4812 		if (preferred != INFINITY_LIFE_TIME) {
4813 			long tval = (jiffies - ifa->tstamp)/HZ;
4814 			if (preferred > tval)
4815 				preferred -= tval;
4816 			else
4817 				preferred = 0;
4818 			if (valid != INFINITY_LIFE_TIME) {
4819 				if (valid > tval)
4820 					valid -= tval;
4821 				else
4822 					valid = 0;
4823 			}
4824 		}
4825 	} else {
4826 		preferred = INFINITY_LIFE_TIME;
4827 		valid = INFINITY_LIFE_TIME;
4828 	}
4829 
4830 	if (!ipv6_addr_any(&ifa->peer_addr)) {
4831 		if (nla_put_in6_addr(skb, IFA_LOCAL, &ifa->addr) < 0 ||
4832 		    nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->peer_addr) < 0)
4833 			goto error;
4834 	} else
4835 		if (nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->addr) < 0)
4836 			goto error;
4837 
4838 	if (ifa->rt_priority &&
4839 	    nla_put_u32(skb, IFA_RT_PRIORITY, ifa->rt_priority))
4840 		goto error;
4841 
4842 	if (put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0)
4843 		goto error;
4844 
4845 	if (nla_put_u32(skb, IFA_FLAGS, ifa->flags) < 0)
4846 		goto error;
4847 
4848 	nlmsg_end(skb, nlh);
4849 	return 0;
4850 
4851 error:
4852 	nlmsg_cancel(skb, nlh);
4853 	return -EMSGSIZE;
4854 }
4855 
4856 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
4857 				u32 portid, u32 seq, int event, u16 flags)
4858 {
4859 	struct nlmsghdr  *nlh;
4860 	u8 scope = RT_SCOPE_UNIVERSE;
4861 	int ifindex = ifmca->idev->dev->ifindex;
4862 
4863 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
4864 		scope = RT_SCOPE_SITE;
4865 
4866 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4867 	if (!nlh)
4868 		return -EMSGSIZE;
4869 
4870 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4871 	if (nla_put_in6_addr(skb, IFA_MULTICAST, &ifmca->mca_addr) < 0 ||
4872 	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
4873 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4874 		nlmsg_cancel(skb, nlh);
4875 		return -EMSGSIZE;
4876 	}
4877 
4878 	nlmsg_end(skb, nlh);
4879 	return 0;
4880 }
4881 
4882 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
4883 				u32 portid, u32 seq, int event, unsigned int flags)
4884 {
4885 	struct net_device *dev = fib6_info_nh_dev(ifaca->aca_rt);
4886 	int ifindex = dev ? dev->ifindex : 1;
4887 	struct nlmsghdr  *nlh;
4888 	u8 scope = RT_SCOPE_UNIVERSE;
4889 
4890 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
4891 		scope = RT_SCOPE_SITE;
4892 
4893 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4894 	if (!nlh)
4895 		return -EMSGSIZE;
4896 
4897 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4898 	if (nla_put_in6_addr(skb, IFA_ANYCAST, &ifaca->aca_addr) < 0 ||
4899 	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
4900 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4901 		nlmsg_cancel(skb, nlh);
4902 		return -EMSGSIZE;
4903 	}
4904 
4905 	nlmsg_end(skb, nlh);
4906 	return 0;
4907 }
4908 
4909 enum addr_type_t {
4910 	UNICAST_ADDR,
4911 	MULTICAST_ADDR,
4912 	ANYCAST_ADDR,
4913 };
4914 
4915 /* called with rcu_read_lock() */
4916 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
4917 			  struct netlink_callback *cb, enum addr_type_t type,
4918 			  int s_ip_idx, int *p_ip_idx)
4919 {
4920 	struct ifmcaddr6 *ifmca;
4921 	struct ifacaddr6 *ifaca;
4922 	int err = 1;
4923 	int ip_idx = *p_ip_idx;
4924 
4925 	read_lock_bh(&idev->lock);
4926 	switch (type) {
4927 	case UNICAST_ADDR: {
4928 		struct inet6_ifaddr *ifa;
4929 
4930 		/* unicast address incl. temp addr */
4931 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
4932 			if (++ip_idx < s_ip_idx)
4933 				continue;
4934 			err = inet6_fill_ifaddr(skb, ifa,
4935 						NETLINK_CB(cb->skb).portid,
4936 						cb->nlh->nlmsg_seq,
4937 						RTM_NEWADDR,
4938 						NLM_F_MULTI);
4939 			if (err < 0)
4940 				break;
4941 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
4942 		}
4943 		break;
4944 	}
4945 	case MULTICAST_ADDR:
4946 		/* multicast address */
4947 		for (ifmca = idev->mc_list; ifmca;
4948 		     ifmca = ifmca->next, ip_idx++) {
4949 			if (ip_idx < s_ip_idx)
4950 				continue;
4951 			err = inet6_fill_ifmcaddr(skb, ifmca,
4952 						  NETLINK_CB(cb->skb).portid,
4953 						  cb->nlh->nlmsg_seq,
4954 						  RTM_GETMULTICAST,
4955 						  NLM_F_MULTI);
4956 			if (err < 0)
4957 				break;
4958 		}
4959 		break;
4960 	case ANYCAST_ADDR:
4961 		/* anycast address */
4962 		for (ifaca = idev->ac_list; ifaca;
4963 		     ifaca = ifaca->aca_next, ip_idx++) {
4964 			if (ip_idx < s_ip_idx)
4965 				continue;
4966 			err = inet6_fill_ifacaddr(skb, ifaca,
4967 						  NETLINK_CB(cb->skb).portid,
4968 						  cb->nlh->nlmsg_seq,
4969 						  RTM_GETANYCAST,
4970 						  NLM_F_MULTI);
4971 			if (err < 0)
4972 				break;
4973 		}
4974 		break;
4975 	default:
4976 		break;
4977 	}
4978 	read_unlock_bh(&idev->lock);
4979 	*p_ip_idx = ip_idx;
4980 	return err;
4981 }
4982 
4983 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
4984 			   enum addr_type_t type)
4985 {
4986 	struct net *net = sock_net(skb->sk);
4987 	int h, s_h;
4988 	int idx, ip_idx;
4989 	int s_idx, s_ip_idx;
4990 	struct net_device *dev;
4991 	struct inet6_dev *idev;
4992 	struct hlist_head *head;
4993 
4994 	s_h = cb->args[0];
4995 	s_idx = idx = cb->args[1];
4996 	s_ip_idx = ip_idx = cb->args[2];
4997 
4998 	rcu_read_lock();
4999 	cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^ net->dev_base_seq;
5000 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
5001 		idx = 0;
5002 		head = &net->dev_index_head[h];
5003 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
5004 			if (idx < s_idx)
5005 				goto cont;
5006 			if (h > s_h || idx > s_idx)
5007 				s_ip_idx = 0;
5008 			ip_idx = 0;
5009 			idev = __in6_dev_get(dev);
5010 			if (!idev)
5011 				goto cont;
5012 
5013 			if (in6_dump_addrs(idev, skb, cb, type,
5014 					   s_ip_idx, &ip_idx) < 0)
5015 				goto done;
5016 cont:
5017 			idx++;
5018 		}
5019 	}
5020 done:
5021 	rcu_read_unlock();
5022 	cb->args[0] = h;
5023 	cb->args[1] = idx;
5024 	cb->args[2] = ip_idx;
5025 
5026 	return skb->len;
5027 }
5028 
5029 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
5030 {
5031 	enum addr_type_t type = UNICAST_ADDR;
5032 
5033 	return inet6_dump_addr(skb, cb, type);
5034 }
5035 
5036 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
5037 {
5038 	enum addr_type_t type = MULTICAST_ADDR;
5039 
5040 	return inet6_dump_addr(skb, cb, type);
5041 }
5042 
5043 
5044 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
5045 {
5046 	enum addr_type_t type = ANYCAST_ADDR;
5047 
5048 	return inet6_dump_addr(skb, cb, type);
5049 }
5050 
5051 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
5052 			     struct netlink_ext_ack *extack)
5053 {
5054 	struct net *net = sock_net(in_skb->sk);
5055 	struct ifaddrmsg *ifm;
5056 	struct nlattr *tb[IFA_MAX+1];
5057 	struct in6_addr *addr = NULL, *peer;
5058 	struct net_device *dev = NULL;
5059 	struct inet6_ifaddr *ifa;
5060 	struct sk_buff *skb;
5061 	int err;
5062 
5063 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy,
5064 			  extack);
5065 	if (err < 0)
5066 		return err;
5067 
5068 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
5069 	if (!addr)
5070 		return -EINVAL;
5071 
5072 	ifm = nlmsg_data(nlh);
5073 	if (ifm->ifa_index)
5074 		dev = dev_get_by_index(net, ifm->ifa_index);
5075 
5076 	ifa = ipv6_get_ifaddr(net, addr, dev, 1);
5077 	if (!ifa) {
5078 		err = -EADDRNOTAVAIL;
5079 		goto errout;
5080 	}
5081 
5082 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
5083 	if (!skb) {
5084 		err = -ENOBUFS;
5085 		goto errout_ifa;
5086 	}
5087 
5088 	err = inet6_fill_ifaddr(skb, ifa, NETLINK_CB(in_skb).portid,
5089 				nlh->nlmsg_seq, RTM_NEWADDR, 0);
5090 	if (err < 0) {
5091 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5092 		WARN_ON(err == -EMSGSIZE);
5093 		kfree_skb(skb);
5094 		goto errout_ifa;
5095 	}
5096 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
5097 errout_ifa:
5098 	in6_ifa_put(ifa);
5099 errout:
5100 	if (dev)
5101 		dev_put(dev);
5102 	return err;
5103 }
5104 
5105 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
5106 {
5107 	struct sk_buff *skb;
5108 	struct net *net = dev_net(ifa->idev->dev);
5109 	int err = -ENOBUFS;
5110 
5111 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
5112 	if (!skb)
5113 		goto errout;
5114 
5115 	err = inet6_fill_ifaddr(skb, ifa, 0, 0, event, 0);
5116 	if (err < 0) {
5117 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5118 		WARN_ON(err == -EMSGSIZE);
5119 		kfree_skb(skb);
5120 		goto errout;
5121 	}
5122 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
5123 	return;
5124 errout:
5125 	if (err < 0)
5126 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
5127 }
5128 
5129 static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
5130 				__s32 *array, int bytes)
5131 {
5132 	BUG_ON(bytes < (DEVCONF_MAX * 4));
5133 
5134 	memset(array, 0, bytes);
5135 	array[DEVCONF_FORWARDING] = cnf->forwarding;
5136 	array[DEVCONF_HOPLIMIT] = cnf->hop_limit;
5137 	array[DEVCONF_MTU6] = cnf->mtu6;
5138 	array[DEVCONF_ACCEPT_RA] = cnf->accept_ra;
5139 	array[DEVCONF_ACCEPT_REDIRECTS] = cnf->accept_redirects;
5140 	array[DEVCONF_AUTOCONF] = cnf->autoconf;
5141 	array[DEVCONF_DAD_TRANSMITS] = cnf->dad_transmits;
5142 	array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
5143 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
5144 		jiffies_to_msecs(cnf->rtr_solicit_interval);
5145 	array[DEVCONF_RTR_SOLICIT_MAX_INTERVAL] =
5146 		jiffies_to_msecs(cnf->rtr_solicit_max_interval);
5147 	array[DEVCONF_RTR_SOLICIT_DELAY] =
5148 		jiffies_to_msecs(cnf->rtr_solicit_delay);
5149 	array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;
5150 	array[DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL] =
5151 		jiffies_to_msecs(cnf->mldv1_unsolicited_report_interval);
5152 	array[DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL] =
5153 		jiffies_to_msecs(cnf->mldv2_unsolicited_report_interval);
5154 	array[DEVCONF_USE_TEMPADDR] = cnf->use_tempaddr;
5155 	array[DEVCONF_TEMP_VALID_LFT] = cnf->temp_valid_lft;
5156 	array[DEVCONF_TEMP_PREFERED_LFT] = cnf->temp_prefered_lft;
5157 	array[DEVCONF_REGEN_MAX_RETRY] = cnf->regen_max_retry;
5158 	array[DEVCONF_MAX_DESYNC_FACTOR] = cnf->max_desync_factor;
5159 	array[DEVCONF_MAX_ADDRESSES] = cnf->max_addresses;
5160 	array[DEVCONF_ACCEPT_RA_DEFRTR] = cnf->accept_ra_defrtr;
5161 	array[DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT] = cnf->accept_ra_min_hop_limit;
5162 	array[DEVCONF_ACCEPT_RA_PINFO] = cnf->accept_ra_pinfo;
5163 #ifdef CONFIG_IPV6_ROUTER_PREF
5164 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = cnf->accept_ra_rtr_pref;
5165 	array[DEVCONF_RTR_PROBE_INTERVAL] =
5166 		jiffies_to_msecs(cnf->rtr_probe_interval);
5167 #ifdef CONFIG_IPV6_ROUTE_INFO
5168 	array[DEVCONF_ACCEPT_RA_RT_INFO_MIN_PLEN] = cnf->accept_ra_rt_info_min_plen;
5169 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
5170 #endif
5171 #endif
5172 	array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
5173 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
5174 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
5175 	array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
5176 	array[DEVCONF_USE_OPTIMISTIC] = cnf->use_optimistic;
5177 #endif
5178 #ifdef CONFIG_IPV6_MROUTE
5179 	array[DEVCONF_MC_FORWARDING] = cnf->mc_forwarding;
5180 #endif
5181 	array[DEVCONF_DISABLE_IPV6] = cnf->disable_ipv6;
5182 	array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad;
5183 	array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao;
5184 	array[DEVCONF_NDISC_NOTIFY] = cnf->ndisc_notify;
5185 	array[DEVCONF_SUPPRESS_FRAG_NDISC] = cnf->suppress_frag_ndisc;
5186 	array[DEVCONF_ACCEPT_RA_FROM_LOCAL] = cnf->accept_ra_from_local;
5187 	array[DEVCONF_ACCEPT_RA_MTU] = cnf->accept_ra_mtu;
5188 	array[DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN] = cnf->ignore_routes_with_linkdown;
5189 	/* we omit DEVCONF_STABLE_SECRET for now */
5190 	array[DEVCONF_USE_OIF_ADDRS_ONLY] = cnf->use_oif_addrs_only;
5191 	array[DEVCONF_DROP_UNICAST_IN_L2_MULTICAST] = cnf->drop_unicast_in_l2_multicast;
5192 	array[DEVCONF_DROP_UNSOLICITED_NA] = cnf->drop_unsolicited_na;
5193 	array[DEVCONF_KEEP_ADDR_ON_DOWN] = cnf->keep_addr_on_down;
5194 	array[DEVCONF_SEG6_ENABLED] = cnf->seg6_enabled;
5195 #ifdef CONFIG_IPV6_SEG6_HMAC
5196 	array[DEVCONF_SEG6_REQUIRE_HMAC] = cnf->seg6_require_hmac;
5197 #endif
5198 	array[DEVCONF_ENHANCED_DAD] = cnf->enhanced_dad;
5199 	array[DEVCONF_ADDR_GEN_MODE] = cnf->addr_gen_mode;
5200 	array[DEVCONF_DISABLE_POLICY] = cnf->disable_policy;
5201 	array[DEVCONF_NDISC_TCLASS] = cnf->ndisc_tclass;
5202 }
5203 
5204 static inline size_t inet6_ifla6_size(void)
5205 {
5206 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
5207 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
5208 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
5209 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
5210 	     + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
5211 	     + nla_total_size(sizeof(struct in6_addr)) /* IFLA_INET6_TOKEN */
5212 	     + nla_total_size(1) /* IFLA_INET6_ADDR_GEN_MODE */
5213 	     + 0;
5214 }
5215 
5216 static inline size_t inet6_if_nlmsg_size(void)
5217 {
5218 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
5219 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
5220 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
5221 	       + nla_total_size(4) /* IFLA_MTU */
5222 	       + nla_total_size(4) /* IFLA_LINK */
5223 	       + nla_total_size(1) /* IFLA_OPERSTATE */
5224 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
5225 }
5226 
5227 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
5228 					int bytes)
5229 {
5230 	int i;
5231 	int pad = bytes - sizeof(u64) * ICMP6_MIB_MAX;
5232 	BUG_ON(pad < 0);
5233 
5234 	/* Use put_unaligned() because stats may not be aligned for u64. */
5235 	put_unaligned(ICMP6_MIB_MAX, &stats[0]);
5236 	for (i = 1; i < ICMP6_MIB_MAX; i++)
5237 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
5238 
5239 	memset(&stats[ICMP6_MIB_MAX], 0, pad);
5240 }
5241 
5242 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu *mib,
5243 					int bytes, size_t syncpoff)
5244 {
5245 	int i, c;
5246 	u64 buff[IPSTATS_MIB_MAX];
5247 	int pad = bytes - sizeof(u64) * IPSTATS_MIB_MAX;
5248 
5249 	BUG_ON(pad < 0);
5250 
5251 	memset(buff, 0, sizeof(buff));
5252 	buff[0] = IPSTATS_MIB_MAX;
5253 
5254 	for_each_possible_cpu(c) {
5255 		for (i = 1; i < IPSTATS_MIB_MAX; i++)
5256 			buff[i] += snmp_get_cpu_field64(mib, c, i, syncpoff);
5257 	}
5258 
5259 	memcpy(stats, buff, IPSTATS_MIB_MAX * sizeof(u64));
5260 	memset(&stats[IPSTATS_MIB_MAX], 0, pad);
5261 }
5262 
5263 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
5264 			     int bytes)
5265 {
5266 	switch (attrtype) {
5267 	case IFLA_INET6_STATS:
5268 		__snmp6_fill_stats64(stats, idev->stats.ipv6, bytes,
5269 				     offsetof(struct ipstats_mib, syncp));
5270 		break;
5271 	case IFLA_INET6_ICMP6STATS:
5272 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, bytes);
5273 		break;
5274 	}
5275 }
5276 
5277 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev,
5278 				  u32 ext_filter_mask)
5279 {
5280 	struct nlattr *nla;
5281 	struct ifla_cacheinfo ci;
5282 
5283 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, idev->if_flags))
5284 		goto nla_put_failure;
5285 	ci.max_reasm_len = IPV6_MAXPLEN;
5286 	ci.tstamp = cstamp_delta(idev->tstamp);
5287 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
5288 	ci.retrans_time = jiffies_to_msecs(NEIGH_VAR(idev->nd_parms, RETRANS_TIME));
5289 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
5290 		goto nla_put_failure;
5291 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
5292 	if (!nla)
5293 		goto nla_put_failure;
5294 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
5295 
5296 	/* XXX - MC not implemented */
5297 
5298 	if (ext_filter_mask & RTEXT_FILTER_SKIP_STATS)
5299 		return 0;
5300 
5301 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
5302 	if (!nla)
5303 		goto nla_put_failure;
5304 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
5305 
5306 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
5307 	if (!nla)
5308 		goto nla_put_failure;
5309 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
5310 
5311 	nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
5312 	if (!nla)
5313 		goto nla_put_failure;
5314 
5315 	if (nla_put_u8(skb, IFLA_INET6_ADDR_GEN_MODE, idev->cnf.addr_gen_mode))
5316 		goto nla_put_failure;
5317 
5318 	read_lock_bh(&idev->lock);
5319 	memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
5320 	read_unlock_bh(&idev->lock);
5321 
5322 	return 0;
5323 
5324 nla_put_failure:
5325 	return -EMSGSIZE;
5326 }
5327 
5328 static size_t inet6_get_link_af_size(const struct net_device *dev,
5329 				     u32 ext_filter_mask)
5330 {
5331 	if (!__in6_dev_get(dev))
5332 		return 0;
5333 
5334 	return inet6_ifla6_size();
5335 }
5336 
5337 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev,
5338 			      u32 ext_filter_mask)
5339 {
5340 	struct inet6_dev *idev = __in6_dev_get(dev);
5341 
5342 	if (!idev)
5343 		return -ENODATA;
5344 
5345 	if (inet6_fill_ifla6_attrs(skb, idev, ext_filter_mask) < 0)
5346 		return -EMSGSIZE;
5347 
5348 	return 0;
5349 }
5350 
5351 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token)
5352 {
5353 	struct inet6_ifaddr *ifp;
5354 	struct net_device *dev = idev->dev;
5355 	bool clear_token, update_rs = false;
5356 	struct in6_addr ll_addr;
5357 
5358 	ASSERT_RTNL();
5359 
5360 	if (!token)
5361 		return -EINVAL;
5362 	if (dev->flags & (IFF_LOOPBACK | IFF_NOARP))
5363 		return -EINVAL;
5364 	if (!ipv6_accept_ra(idev))
5365 		return -EINVAL;
5366 	if (idev->cnf.rtr_solicits == 0)
5367 		return -EINVAL;
5368 
5369 	write_lock_bh(&idev->lock);
5370 
5371 	BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
5372 	memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
5373 
5374 	write_unlock_bh(&idev->lock);
5375 
5376 	clear_token = ipv6_addr_any(token);
5377 	if (clear_token)
5378 		goto update_lft;
5379 
5380 	if (!idev->dead && (idev->if_flags & IF_READY) &&
5381 	    !ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
5382 			     IFA_F_OPTIMISTIC)) {
5383 		/* If we're not ready, then normal ifup will take care
5384 		 * of this. Otherwise, we need to request our rs here.
5385 		 */
5386 		ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
5387 		update_rs = true;
5388 	}
5389 
5390 update_lft:
5391 	write_lock_bh(&idev->lock);
5392 
5393 	if (update_rs) {
5394 		idev->if_flags |= IF_RS_SENT;
5395 		idev->rs_interval = rfc3315_s14_backoff_init(
5396 			idev->cnf.rtr_solicit_interval);
5397 		idev->rs_probes = 1;
5398 		addrconf_mod_rs_timer(idev, idev->rs_interval);
5399 	}
5400 
5401 	/* Well, that's kinda nasty ... */
5402 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
5403 		spin_lock(&ifp->lock);
5404 		if (ifp->tokenized) {
5405 			ifp->valid_lft = 0;
5406 			ifp->prefered_lft = 0;
5407 		}
5408 		spin_unlock(&ifp->lock);
5409 	}
5410 
5411 	write_unlock_bh(&idev->lock);
5412 	inet6_ifinfo_notify(RTM_NEWLINK, idev);
5413 	addrconf_verify_rtnl();
5414 	return 0;
5415 }
5416 
5417 static const struct nla_policy inet6_af_policy[IFLA_INET6_MAX + 1] = {
5418 	[IFLA_INET6_ADDR_GEN_MODE]	= { .type = NLA_U8 },
5419 	[IFLA_INET6_TOKEN]		= { .len = sizeof(struct in6_addr) },
5420 };
5421 
5422 static int inet6_validate_link_af(const struct net_device *dev,
5423 				  const struct nlattr *nla)
5424 {
5425 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5426 
5427 	if (dev && !__in6_dev_get(dev))
5428 		return -EAFNOSUPPORT;
5429 
5430 	return nla_parse_nested(tb, IFLA_INET6_MAX, nla, inet6_af_policy,
5431 				NULL);
5432 }
5433 
5434 static int check_addr_gen_mode(int mode)
5435 {
5436 	if (mode != IN6_ADDR_GEN_MODE_EUI64 &&
5437 	    mode != IN6_ADDR_GEN_MODE_NONE &&
5438 	    mode != IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5439 	    mode != IN6_ADDR_GEN_MODE_RANDOM)
5440 		return -EINVAL;
5441 	return 1;
5442 }
5443 
5444 static int check_stable_privacy(struct inet6_dev *idev, struct net *net,
5445 				int mode)
5446 {
5447 	if (mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5448 	    !idev->cnf.stable_secret.initialized &&
5449 	    !net->ipv6.devconf_dflt->stable_secret.initialized)
5450 		return -EINVAL;
5451 	return 1;
5452 }
5453 
5454 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla)
5455 {
5456 	int err = -EINVAL;
5457 	struct inet6_dev *idev = __in6_dev_get(dev);
5458 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5459 
5460 	if (!idev)
5461 		return -EAFNOSUPPORT;
5462 
5463 	if (nla_parse_nested(tb, IFLA_INET6_MAX, nla, NULL, NULL) < 0)
5464 		BUG();
5465 
5466 	if (tb[IFLA_INET6_TOKEN]) {
5467 		err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]));
5468 		if (err)
5469 			return err;
5470 	}
5471 
5472 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
5473 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
5474 
5475 		if (check_addr_gen_mode(mode) < 0 ||
5476 		    check_stable_privacy(idev, dev_net(dev), mode) < 0)
5477 			return -EINVAL;
5478 
5479 		idev->cnf.addr_gen_mode = mode;
5480 		err = 0;
5481 	}
5482 
5483 	return err;
5484 }
5485 
5486 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
5487 			     u32 portid, u32 seq, int event, unsigned int flags)
5488 {
5489 	struct net_device *dev = idev->dev;
5490 	struct ifinfomsg *hdr;
5491 	struct nlmsghdr *nlh;
5492 	void *protoinfo;
5493 
5494 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
5495 	if (!nlh)
5496 		return -EMSGSIZE;
5497 
5498 	hdr = nlmsg_data(nlh);
5499 	hdr->ifi_family = AF_INET6;
5500 	hdr->__ifi_pad = 0;
5501 	hdr->ifi_type = dev->type;
5502 	hdr->ifi_index = dev->ifindex;
5503 	hdr->ifi_flags = dev_get_flags(dev);
5504 	hdr->ifi_change = 0;
5505 
5506 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
5507 	    (dev->addr_len &&
5508 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
5509 	    nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
5510 	    (dev->ifindex != dev_get_iflink(dev) &&
5511 	     nla_put_u32(skb, IFLA_LINK, dev_get_iflink(dev))) ||
5512 	    nla_put_u8(skb, IFLA_OPERSTATE,
5513 		       netif_running(dev) ? dev->operstate : IF_OPER_DOWN))
5514 		goto nla_put_failure;
5515 	protoinfo = nla_nest_start(skb, IFLA_PROTINFO);
5516 	if (!protoinfo)
5517 		goto nla_put_failure;
5518 
5519 	if (inet6_fill_ifla6_attrs(skb, idev, 0) < 0)
5520 		goto nla_put_failure;
5521 
5522 	nla_nest_end(skb, protoinfo);
5523 	nlmsg_end(skb, nlh);
5524 	return 0;
5525 
5526 nla_put_failure:
5527 	nlmsg_cancel(skb, nlh);
5528 	return -EMSGSIZE;
5529 }
5530 
5531 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
5532 {
5533 	struct net *net = sock_net(skb->sk);
5534 	int h, s_h;
5535 	int idx = 0, s_idx;
5536 	struct net_device *dev;
5537 	struct inet6_dev *idev;
5538 	struct hlist_head *head;
5539 
5540 	s_h = cb->args[0];
5541 	s_idx = cb->args[1];
5542 
5543 	rcu_read_lock();
5544 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
5545 		idx = 0;
5546 		head = &net->dev_index_head[h];
5547 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
5548 			if (idx < s_idx)
5549 				goto cont;
5550 			idev = __in6_dev_get(dev);
5551 			if (!idev)
5552 				goto cont;
5553 			if (inet6_fill_ifinfo(skb, idev,
5554 					      NETLINK_CB(cb->skb).portid,
5555 					      cb->nlh->nlmsg_seq,
5556 					      RTM_NEWLINK, NLM_F_MULTI) < 0)
5557 				goto out;
5558 cont:
5559 			idx++;
5560 		}
5561 	}
5562 out:
5563 	rcu_read_unlock();
5564 	cb->args[1] = idx;
5565 	cb->args[0] = h;
5566 
5567 	return skb->len;
5568 }
5569 
5570 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
5571 {
5572 	struct sk_buff *skb;
5573 	struct net *net = dev_net(idev->dev);
5574 	int err = -ENOBUFS;
5575 
5576 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
5577 	if (!skb)
5578 		goto errout;
5579 
5580 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
5581 	if (err < 0) {
5582 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
5583 		WARN_ON(err == -EMSGSIZE);
5584 		kfree_skb(skb);
5585 		goto errout;
5586 	}
5587 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
5588 	return;
5589 errout:
5590 	if (err < 0)
5591 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
5592 }
5593 
5594 static inline size_t inet6_prefix_nlmsg_size(void)
5595 {
5596 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
5597 	       + nla_total_size(sizeof(struct in6_addr))
5598 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
5599 }
5600 
5601 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
5602 			     struct prefix_info *pinfo, u32 portid, u32 seq,
5603 			     int event, unsigned int flags)
5604 {
5605 	struct prefixmsg *pmsg;
5606 	struct nlmsghdr *nlh;
5607 	struct prefix_cacheinfo	ci;
5608 
5609 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
5610 	if (!nlh)
5611 		return -EMSGSIZE;
5612 
5613 	pmsg = nlmsg_data(nlh);
5614 	pmsg->prefix_family = AF_INET6;
5615 	pmsg->prefix_pad1 = 0;
5616 	pmsg->prefix_pad2 = 0;
5617 	pmsg->prefix_ifindex = idev->dev->ifindex;
5618 	pmsg->prefix_len = pinfo->prefix_len;
5619 	pmsg->prefix_type = pinfo->type;
5620 	pmsg->prefix_pad3 = 0;
5621 	pmsg->prefix_flags = 0;
5622 	if (pinfo->onlink)
5623 		pmsg->prefix_flags |= IF_PREFIX_ONLINK;
5624 	if (pinfo->autoconf)
5625 		pmsg->prefix_flags |= IF_PREFIX_AUTOCONF;
5626 
5627 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
5628 		goto nla_put_failure;
5629 	ci.preferred_time = ntohl(pinfo->prefered);
5630 	ci.valid_time = ntohl(pinfo->valid);
5631 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
5632 		goto nla_put_failure;
5633 	nlmsg_end(skb, nlh);
5634 	return 0;
5635 
5636 nla_put_failure:
5637 	nlmsg_cancel(skb, nlh);
5638 	return -EMSGSIZE;
5639 }
5640 
5641 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
5642 			 struct prefix_info *pinfo)
5643 {
5644 	struct sk_buff *skb;
5645 	struct net *net = dev_net(idev->dev);
5646 	int err = -ENOBUFS;
5647 
5648 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
5649 	if (!skb)
5650 		goto errout;
5651 
5652 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
5653 	if (err < 0) {
5654 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
5655 		WARN_ON(err == -EMSGSIZE);
5656 		kfree_skb(skb);
5657 		goto errout;
5658 	}
5659 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
5660 	return;
5661 errout:
5662 	if (err < 0)
5663 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
5664 }
5665 
5666 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
5667 {
5668 	struct net *net = dev_net(ifp->idev->dev);
5669 
5670 	if (event)
5671 		ASSERT_RTNL();
5672 
5673 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
5674 
5675 	switch (event) {
5676 	case RTM_NEWADDR:
5677 		/*
5678 		 * If the address was optimistic
5679 		 * we inserted the route at the start of
5680 		 * our DAD process, so we don't need
5681 		 * to do it again
5682 		 */
5683 		if (!rcu_access_pointer(ifp->rt->fib6_node))
5684 			ip6_ins_rt(net, ifp->rt);
5685 		if (ifp->idev->cnf.forwarding)
5686 			addrconf_join_anycast(ifp);
5687 		if (!ipv6_addr_any(&ifp->peer_addr))
5688 			addrconf_prefix_route(&ifp->peer_addr, 128, 0,
5689 					      ifp->idev->dev, 0, 0,
5690 					      GFP_ATOMIC);
5691 		break;
5692 	case RTM_DELADDR:
5693 		if (ifp->idev->cnf.forwarding)
5694 			addrconf_leave_anycast(ifp);
5695 		addrconf_leave_solict(ifp->idev, &ifp->addr);
5696 		if (!ipv6_addr_any(&ifp->peer_addr)) {
5697 			struct fib6_info *rt;
5698 
5699 			rt = addrconf_get_prefix_route(&ifp->peer_addr, 128,
5700 						       ifp->idev->dev, 0, 0);
5701 			if (rt)
5702 				ip6_del_rt(net, rt);
5703 		}
5704 		if (ifp->rt) {
5705 			ip6_del_rt(net, ifp->rt);
5706 			ifp->rt = NULL;
5707 		}
5708 		rt_genid_bump_ipv6(net);
5709 		break;
5710 	}
5711 	atomic_inc(&net->ipv6.dev_addr_genid);
5712 }
5713 
5714 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
5715 {
5716 	rcu_read_lock_bh();
5717 	if (likely(ifp->idev->dead == 0))
5718 		__ipv6_ifa_notify(event, ifp);
5719 	rcu_read_unlock_bh();
5720 }
5721 
5722 #ifdef CONFIG_SYSCTL
5723 
5724 static
5725 int addrconf_sysctl_forward(struct ctl_table *ctl, int write,
5726 			   void __user *buffer, size_t *lenp, loff_t *ppos)
5727 {
5728 	int *valp = ctl->data;
5729 	int val = *valp;
5730 	loff_t pos = *ppos;
5731 	struct ctl_table lctl;
5732 	int ret;
5733 
5734 	/*
5735 	 * ctl->data points to idev->cnf.forwarding, we should
5736 	 * not modify it until we get the rtnl lock.
5737 	 */
5738 	lctl = *ctl;
5739 	lctl.data = &val;
5740 
5741 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5742 
5743 	if (write)
5744 		ret = addrconf_fixup_forwarding(ctl, valp, val);
5745 	if (ret)
5746 		*ppos = pos;
5747 	return ret;
5748 }
5749 
5750 static
5751 int addrconf_sysctl_mtu(struct ctl_table *ctl, int write,
5752 			void __user *buffer, size_t *lenp, loff_t *ppos)
5753 {
5754 	struct inet6_dev *idev = ctl->extra1;
5755 	int min_mtu = IPV6_MIN_MTU;
5756 	struct ctl_table lctl;
5757 
5758 	lctl = *ctl;
5759 	lctl.extra1 = &min_mtu;
5760 	lctl.extra2 = idev ? &idev->dev->mtu : NULL;
5761 
5762 	return proc_dointvec_minmax(&lctl, write, buffer, lenp, ppos);
5763 }
5764 
5765 static void dev_disable_change(struct inet6_dev *idev)
5766 {
5767 	struct netdev_notifier_info info;
5768 
5769 	if (!idev || !idev->dev)
5770 		return;
5771 
5772 	netdev_notifier_info_init(&info, idev->dev);
5773 	if (idev->cnf.disable_ipv6)
5774 		addrconf_notify(NULL, NETDEV_DOWN, &info);
5775 	else
5776 		addrconf_notify(NULL, NETDEV_UP, &info);
5777 }
5778 
5779 static void addrconf_disable_change(struct net *net, __s32 newf)
5780 {
5781 	struct net_device *dev;
5782 	struct inet6_dev *idev;
5783 
5784 	for_each_netdev(net, dev) {
5785 		idev = __in6_dev_get(dev);
5786 		if (idev) {
5787 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
5788 			idev->cnf.disable_ipv6 = newf;
5789 			if (changed)
5790 				dev_disable_change(idev);
5791 		}
5792 	}
5793 }
5794 
5795 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
5796 {
5797 	struct net *net;
5798 	int old;
5799 
5800 	if (!rtnl_trylock())
5801 		return restart_syscall();
5802 
5803 	net = (struct net *)table->extra2;
5804 	old = *p;
5805 	*p = newf;
5806 
5807 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
5808 		rtnl_unlock();
5809 		return 0;
5810 	}
5811 
5812 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
5813 		net->ipv6.devconf_dflt->disable_ipv6 = newf;
5814 		addrconf_disable_change(net, newf);
5815 	} else if ((!newf) ^ (!old))
5816 		dev_disable_change((struct inet6_dev *)table->extra1);
5817 
5818 	rtnl_unlock();
5819 	return 0;
5820 }
5821 
5822 static
5823 int addrconf_sysctl_disable(struct ctl_table *ctl, int write,
5824 			    void __user *buffer, size_t *lenp, loff_t *ppos)
5825 {
5826 	int *valp = ctl->data;
5827 	int val = *valp;
5828 	loff_t pos = *ppos;
5829 	struct ctl_table lctl;
5830 	int ret;
5831 
5832 	/*
5833 	 * ctl->data points to idev->cnf.disable_ipv6, we should
5834 	 * not modify it until we get the rtnl lock.
5835 	 */
5836 	lctl = *ctl;
5837 	lctl.data = &val;
5838 
5839 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5840 
5841 	if (write)
5842 		ret = addrconf_disable_ipv6(ctl, valp, val);
5843 	if (ret)
5844 		*ppos = pos;
5845 	return ret;
5846 }
5847 
5848 static
5849 int addrconf_sysctl_proxy_ndp(struct ctl_table *ctl, int write,
5850 			      void __user *buffer, size_t *lenp, loff_t *ppos)
5851 {
5852 	int *valp = ctl->data;
5853 	int ret;
5854 	int old, new;
5855 
5856 	old = *valp;
5857 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
5858 	new = *valp;
5859 
5860 	if (write && old != new) {
5861 		struct net *net = ctl->extra2;
5862 
5863 		if (!rtnl_trylock())
5864 			return restart_syscall();
5865 
5866 		if (valp == &net->ipv6.devconf_dflt->proxy_ndp)
5867 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
5868 						     NETCONFA_PROXY_NEIGH,
5869 						     NETCONFA_IFINDEX_DEFAULT,
5870 						     net->ipv6.devconf_dflt);
5871 		else if (valp == &net->ipv6.devconf_all->proxy_ndp)
5872 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
5873 						     NETCONFA_PROXY_NEIGH,
5874 						     NETCONFA_IFINDEX_ALL,
5875 						     net->ipv6.devconf_all);
5876 		else {
5877 			struct inet6_dev *idev = ctl->extra1;
5878 
5879 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
5880 						     NETCONFA_PROXY_NEIGH,
5881 						     idev->dev->ifindex,
5882 						     &idev->cnf);
5883 		}
5884 		rtnl_unlock();
5885 	}
5886 
5887 	return ret;
5888 }
5889 
5890 static int addrconf_sysctl_addr_gen_mode(struct ctl_table *ctl, int write,
5891 					 void __user *buffer, size_t *lenp,
5892 					 loff_t *ppos)
5893 {
5894 	int ret = 0;
5895 	u32 new_val;
5896 	struct inet6_dev *idev = (struct inet6_dev *)ctl->extra1;
5897 	struct net *net = (struct net *)ctl->extra2;
5898 	struct ctl_table tmp = {
5899 		.data = &new_val,
5900 		.maxlen = sizeof(new_val),
5901 		.mode = ctl->mode,
5902 	};
5903 
5904 	if (!rtnl_trylock())
5905 		return restart_syscall();
5906 
5907 	new_val = *((u32 *)ctl->data);
5908 
5909 	ret = proc_douintvec(&tmp, write, buffer, lenp, ppos);
5910 	if (ret != 0)
5911 		goto out;
5912 
5913 	if (write) {
5914 		if (check_addr_gen_mode(new_val) < 0) {
5915 			ret = -EINVAL;
5916 			goto out;
5917 		}
5918 
5919 		if (idev) {
5920 			if (check_stable_privacy(idev, net, new_val) < 0) {
5921 				ret = -EINVAL;
5922 				goto out;
5923 			}
5924 
5925 			if (idev->cnf.addr_gen_mode != new_val) {
5926 				idev->cnf.addr_gen_mode = new_val;
5927 				addrconf_dev_config(idev->dev);
5928 			}
5929 		} else if (&net->ipv6.devconf_all->addr_gen_mode == ctl->data) {
5930 			struct net_device *dev;
5931 
5932 			net->ipv6.devconf_dflt->addr_gen_mode = new_val;
5933 			for_each_netdev(net, dev) {
5934 				idev = __in6_dev_get(dev);
5935 				if (idev &&
5936 				    idev->cnf.addr_gen_mode != new_val) {
5937 					idev->cnf.addr_gen_mode = new_val;
5938 					addrconf_dev_config(idev->dev);
5939 				}
5940 			}
5941 		}
5942 
5943 		*((u32 *)ctl->data) = new_val;
5944 	}
5945 
5946 out:
5947 	rtnl_unlock();
5948 
5949 	return ret;
5950 }
5951 
5952 static int addrconf_sysctl_stable_secret(struct ctl_table *ctl, int write,
5953 					 void __user *buffer, size_t *lenp,
5954 					 loff_t *ppos)
5955 {
5956 	int err;
5957 	struct in6_addr addr;
5958 	char str[IPV6_MAX_STRLEN];
5959 	struct ctl_table lctl = *ctl;
5960 	struct net *net = ctl->extra2;
5961 	struct ipv6_stable_secret *secret = ctl->data;
5962 
5963 	if (&net->ipv6.devconf_all->stable_secret == ctl->data)
5964 		return -EIO;
5965 
5966 	lctl.maxlen = IPV6_MAX_STRLEN;
5967 	lctl.data = str;
5968 
5969 	if (!rtnl_trylock())
5970 		return restart_syscall();
5971 
5972 	if (!write && !secret->initialized) {
5973 		err = -EIO;
5974 		goto out;
5975 	}
5976 
5977 	err = snprintf(str, sizeof(str), "%pI6", &secret->secret);
5978 	if (err >= sizeof(str)) {
5979 		err = -EIO;
5980 		goto out;
5981 	}
5982 
5983 	err = proc_dostring(&lctl, write, buffer, lenp, ppos);
5984 	if (err || !write)
5985 		goto out;
5986 
5987 	if (in6_pton(str, -1, addr.in6_u.u6_addr8, -1, NULL) != 1) {
5988 		err = -EIO;
5989 		goto out;
5990 	}
5991 
5992 	secret->initialized = true;
5993 	secret->secret = addr;
5994 
5995 	if (&net->ipv6.devconf_dflt->stable_secret == ctl->data) {
5996 		struct net_device *dev;
5997 
5998 		for_each_netdev(net, dev) {
5999 			struct inet6_dev *idev = __in6_dev_get(dev);
6000 
6001 			if (idev) {
6002 				idev->cnf.addr_gen_mode =
6003 					IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
6004 			}
6005 		}
6006 	} else {
6007 		struct inet6_dev *idev = ctl->extra1;
6008 
6009 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
6010 	}
6011 
6012 out:
6013 	rtnl_unlock();
6014 
6015 	return err;
6016 }
6017 
6018 static
6019 int addrconf_sysctl_ignore_routes_with_linkdown(struct ctl_table *ctl,
6020 						int write,
6021 						void __user *buffer,
6022 						size_t *lenp,
6023 						loff_t *ppos)
6024 {
6025 	int *valp = ctl->data;
6026 	int val = *valp;
6027 	loff_t pos = *ppos;
6028 	struct ctl_table lctl;
6029 	int ret;
6030 
6031 	/* ctl->data points to idev->cnf.ignore_routes_when_linkdown
6032 	 * we should not modify it until we get the rtnl lock.
6033 	 */
6034 	lctl = *ctl;
6035 	lctl.data = &val;
6036 
6037 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6038 
6039 	if (write)
6040 		ret = addrconf_fixup_linkdown(ctl, valp, val);
6041 	if (ret)
6042 		*ppos = pos;
6043 	return ret;
6044 }
6045 
6046 static
6047 void addrconf_set_nopolicy(struct rt6_info *rt, int action)
6048 {
6049 	if (rt) {
6050 		if (action)
6051 			rt->dst.flags |= DST_NOPOLICY;
6052 		else
6053 			rt->dst.flags &= ~DST_NOPOLICY;
6054 	}
6055 }
6056 
6057 static
6058 void addrconf_disable_policy_idev(struct inet6_dev *idev, int val)
6059 {
6060 	struct inet6_ifaddr *ifa;
6061 
6062 	read_lock_bh(&idev->lock);
6063 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
6064 		spin_lock(&ifa->lock);
6065 		if (ifa->rt) {
6066 			struct fib6_info *rt = ifa->rt;
6067 			int cpu;
6068 
6069 			rcu_read_lock();
6070 			ifa->rt->dst_nopolicy = val ? true : false;
6071 			if (rt->rt6i_pcpu) {
6072 				for_each_possible_cpu(cpu) {
6073 					struct rt6_info **rtp;
6074 
6075 					rtp = per_cpu_ptr(rt->rt6i_pcpu, cpu);
6076 					addrconf_set_nopolicy(*rtp, val);
6077 				}
6078 			}
6079 			rcu_read_unlock();
6080 		}
6081 		spin_unlock(&ifa->lock);
6082 	}
6083 	read_unlock_bh(&idev->lock);
6084 }
6085 
6086 static
6087 int addrconf_disable_policy(struct ctl_table *ctl, int *valp, int val)
6088 {
6089 	struct inet6_dev *idev;
6090 	struct net *net;
6091 
6092 	if (!rtnl_trylock())
6093 		return restart_syscall();
6094 
6095 	*valp = val;
6096 
6097 	net = (struct net *)ctl->extra2;
6098 	if (valp == &net->ipv6.devconf_dflt->disable_policy) {
6099 		rtnl_unlock();
6100 		return 0;
6101 	}
6102 
6103 	if (valp == &net->ipv6.devconf_all->disable_policy)  {
6104 		struct net_device *dev;
6105 
6106 		for_each_netdev(net, dev) {
6107 			idev = __in6_dev_get(dev);
6108 			if (idev)
6109 				addrconf_disable_policy_idev(idev, val);
6110 		}
6111 	} else {
6112 		idev = (struct inet6_dev *)ctl->extra1;
6113 		addrconf_disable_policy_idev(idev, val);
6114 	}
6115 
6116 	rtnl_unlock();
6117 	return 0;
6118 }
6119 
6120 static
6121 int addrconf_sysctl_disable_policy(struct ctl_table *ctl, int write,
6122 				   void __user *buffer, size_t *lenp,
6123 				   loff_t *ppos)
6124 {
6125 	int *valp = ctl->data;
6126 	int val = *valp;
6127 	loff_t pos = *ppos;
6128 	struct ctl_table lctl;
6129 	int ret;
6130 
6131 	lctl = *ctl;
6132 	lctl.data = &val;
6133 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6134 
6135 	if (write && (*valp != val))
6136 		ret = addrconf_disable_policy(ctl, valp, val);
6137 
6138 	if (ret)
6139 		*ppos = pos;
6140 
6141 	return ret;
6142 }
6143 
6144 static int minus_one = -1;
6145 static const int zero = 0;
6146 static const int one = 1;
6147 static const int two_five_five = 255;
6148 
6149 static const struct ctl_table addrconf_sysctl[] = {
6150 	{
6151 		.procname	= "forwarding",
6152 		.data		= &ipv6_devconf.forwarding,
6153 		.maxlen		= sizeof(int),
6154 		.mode		= 0644,
6155 		.proc_handler	= addrconf_sysctl_forward,
6156 	},
6157 	{
6158 		.procname	= "hop_limit",
6159 		.data		= &ipv6_devconf.hop_limit,
6160 		.maxlen		= sizeof(int),
6161 		.mode		= 0644,
6162 		.proc_handler	= proc_dointvec_minmax,
6163 		.extra1		= (void *)&one,
6164 		.extra2		= (void *)&two_five_five,
6165 	},
6166 	{
6167 		.procname	= "mtu",
6168 		.data		= &ipv6_devconf.mtu6,
6169 		.maxlen		= sizeof(int),
6170 		.mode		= 0644,
6171 		.proc_handler	= addrconf_sysctl_mtu,
6172 	},
6173 	{
6174 		.procname	= "accept_ra",
6175 		.data		= &ipv6_devconf.accept_ra,
6176 		.maxlen		= sizeof(int),
6177 		.mode		= 0644,
6178 		.proc_handler	= proc_dointvec,
6179 	},
6180 	{
6181 		.procname	= "accept_redirects",
6182 		.data		= &ipv6_devconf.accept_redirects,
6183 		.maxlen		= sizeof(int),
6184 		.mode		= 0644,
6185 		.proc_handler	= proc_dointvec,
6186 	},
6187 	{
6188 		.procname	= "autoconf",
6189 		.data		= &ipv6_devconf.autoconf,
6190 		.maxlen		= sizeof(int),
6191 		.mode		= 0644,
6192 		.proc_handler	= proc_dointvec,
6193 	},
6194 	{
6195 		.procname	= "dad_transmits",
6196 		.data		= &ipv6_devconf.dad_transmits,
6197 		.maxlen		= sizeof(int),
6198 		.mode		= 0644,
6199 		.proc_handler	= proc_dointvec,
6200 	},
6201 	{
6202 		.procname	= "router_solicitations",
6203 		.data		= &ipv6_devconf.rtr_solicits,
6204 		.maxlen		= sizeof(int),
6205 		.mode		= 0644,
6206 		.proc_handler	= proc_dointvec_minmax,
6207 		.extra1		= &minus_one,
6208 	},
6209 	{
6210 		.procname	= "router_solicitation_interval",
6211 		.data		= &ipv6_devconf.rtr_solicit_interval,
6212 		.maxlen		= sizeof(int),
6213 		.mode		= 0644,
6214 		.proc_handler	= proc_dointvec_jiffies,
6215 	},
6216 	{
6217 		.procname	= "router_solicitation_max_interval",
6218 		.data		= &ipv6_devconf.rtr_solicit_max_interval,
6219 		.maxlen		= sizeof(int),
6220 		.mode		= 0644,
6221 		.proc_handler	= proc_dointvec_jiffies,
6222 	},
6223 	{
6224 		.procname	= "router_solicitation_delay",
6225 		.data		= &ipv6_devconf.rtr_solicit_delay,
6226 		.maxlen		= sizeof(int),
6227 		.mode		= 0644,
6228 		.proc_handler	= proc_dointvec_jiffies,
6229 	},
6230 	{
6231 		.procname	= "force_mld_version",
6232 		.data		= &ipv6_devconf.force_mld_version,
6233 		.maxlen		= sizeof(int),
6234 		.mode		= 0644,
6235 		.proc_handler	= proc_dointvec,
6236 	},
6237 	{
6238 		.procname	= "mldv1_unsolicited_report_interval",
6239 		.data		=
6240 			&ipv6_devconf.mldv1_unsolicited_report_interval,
6241 		.maxlen		= sizeof(int),
6242 		.mode		= 0644,
6243 		.proc_handler	= proc_dointvec_ms_jiffies,
6244 	},
6245 	{
6246 		.procname	= "mldv2_unsolicited_report_interval",
6247 		.data		=
6248 			&ipv6_devconf.mldv2_unsolicited_report_interval,
6249 		.maxlen		= sizeof(int),
6250 		.mode		= 0644,
6251 		.proc_handler	= proc_dointvec_ms_jiffies,
6252 	},
6253 	{
6254 		.procname	= "use_tempaddr",
6255 		.data		= &ipv6_devconf.use_tempaddr,
6256 		.maxlen		= sizeof(int),
6257 		.mode		= 0644,
6258 		.proc_handler	= proc_dointvec,
6259 	},
6260 	{
6261 		.procname	= "temp_valid_lft",
6262 		.data		= &ipv6_devconf.temp_valid_lft,
6263 		.maxlen		= sizeof(int),
6264 		.mode		= 0644,
6265 		.proc_handler	= proc_dointvec,
6266 	},
6267 	{
6268 		.procname	= "temp_prefered_lft",
6269 		.data		= &ipv6_devconf.temp_prefered_lft,
6270 		.maxlen		= sizeof(int),
6271 		.mode		= 0644,
6272 		.proc_handler	= proc_dointvec,
6273 	},
6274 	{
6275 		.procname	= "regen_max_retry",
6276 		.data		= &ipv6_devconf.regen_max_retry,
6277 		.maxlen		= sizeof(int),
6278 		.mode		= 0644,
6279 		.proc_handler	= proc_dointvec,
6280 	},
6281 	{
6282 		.procname	= "max_desync_factor",
6283 		.data		= &ipv6_devconf.max_desync_factor,
6284 		.maxlen		= sizeof(int),
6285 		.mode		= 0644,
6286 		.proc_handler	= proc_dointvec,
6287 	},
6288 	{
6289 		.procname	= "max_addresses",
6290 		.data		= &ipv6_devconf.max_addresses,
6291 		.maxlen		= sizeof(int),
6292 		.mode		= 0644,
6293 		.proc_handler	= proc_dointvec,
6294 	},
6295 	{
6296 		.procname	= "accept_ra_defrtr",
6297 		.data		= &ipv6_devconf.accept_ra_defrtr,
6298 		.maxlen		= sizeof(int),
6299 		.mode		= 0644,
6300 		.proc_handler	= proc_dointvec,
6301 	},
6302 	{
6303 		.procname	= "accept_ra_min_hop_limit",
6304 		.data		= &ipv6_devconf.accept_ra_min_hop_limit,
6305 		.maxlen		= sizeof(int),
6306 		.mode		= 0644,
6307 		.proc_handler	= proc_dointvec,
6308 	},
6309 	{
6310 		.procname	= "accept_ra_pinfo",
6311 		.data		= &ipv6_devconf.accept_ra_pinfo,
6312 		.maxlen		= sizeof(int),
6313 		.mode		= 0644,
6314 		.proc_handler	= proc_dointvec,
6315 	},
6316 #ifdef CONFIG_IPV6_ROUTER_PREF
6317 	{
6318 		.procname	= "accept_ra_rtr_pref",
6319 		.data		= &ipv6_devconf.accept_ra_rtr_pref,
6320 		.maxlen		= sizeof(int),
6321 		.mode		= 0644,
6322 		.proc_handler	= proc_dointvec,
6323 	},
6324 	{
6325 		.procname	= "router_probe_interval",
6326 		.data		= &ipv6_devconf.rtr_probe_interval,
6327 		.maxlen		= sizeof(int),
6328 		.mode		= 0644,
6329 		.proc_handler	= proc_dointvec_jiffies,
6330 	},
6331 #ifdef CONFIG_IPV6_ROUTE_INFO
6332 	{
6333 		.procname	= "accept_ra_rt_info_min_plen",
6334 		.data		= &ipv6_devconf.accept_ra_rt_info_min_plen,
6335 		.maxlen		= sizeof(int),
6336 		.mode		= 0644,
6337 		.proc_handler	= proc_dointvec,
6338 	},
6339 	{
6340 		.procname	= "accept_ra_rt_info_max_plen",
6341 		.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
6342 		.maxlen		= sizeof(int),
6343 		.mode		= 0644,
6344 		.proc_handler	= proc_dointvec,
6345 	},
6346 #endif
6347 #endif
6348 	{
6349 		.procname	= "proxy_ndp",
6350 		.data		= &ipv6_devconf.proxy_ndp,
6351 		.maxlen		= sizeof(int),
6352 		.mode		= 0644,
6353 		.proc_handler	= addrconf_sysctl_proxy_ndp,
6354 	},
6355 	{
6356 		.procname	= "accept_source_route",
6357 		.data		= &ipv6_devconf.accept_source_route,
6358 		.maxlen		= sizeof(int),
6359 		.mode		= 0644,
6360 		.proc_handler	= proc_dointvec,
6361 	},
6362 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
6363 	{
6364 		.procname	= "optimistic_dad",
6365 		.data		= &ipv6_devconf.optimistic_dad,
6366 		.maxlen		= sizeof(int),
6367 		.mode		= 0644,
6368 		.proc_handler   = proc_dointvec,
6369 	},
6370 	{
6371 		.procname	= "use_optimistic",
6372 		.data		= &ipv6_devconf.use_optimistic,
6373 		.maxlen		= sizeof(int),
6374 		.mode		= 0644,
6375 		.proc_handler	= proc_dointvec,
6376 	},
6377 #endif
6378 #ifdef CONFIG_IPV6_MROUTE
6379 	{
6380 		.procname	= "mc_forwarding",
6381 		.data		= &ipv6_devconf.mc_forwarding,
6382 		.maxlen		= sizeof(int),
6383 		.mode		= 0444,
6384 		.proc_handler	= proc_dointvec,
6385 	},
6386 #endif
6387 	{
6388 		.procname	= "disable_ipv6",
6389 		.data		= &ipv6_devconf.disable_ipv6,
6390 		.maxlen		= sizeof(int),
6391 		.mode		= 0644,
6392 		.proc_handler	= addrconf_sysctl_disable,
6393 	},
6394 	{
6395 		.procname	= "accept_dad",
6396 		.data		= &ipv6_devconf.accept_dad,
6397 		.maxlen		= sizeof(int),
6398 		.mode		= 0644,
6399 		.proc_handler	= proc_dointvec,
6400 	},
6401 	{
6402 		.procname	= "force_tllao",
6403 		.data		= &ipv6_devconf.force_tllao,
6404 		.maxlen		= sizeof(int),
6405 		.mode		= 0644,
6406 		.proc_handler	= proc_dointvec
6407 	},
6408 	{
6409 		.procname	= "ndisc_notify",
6410 		.data		= &ipv6_devconf.ndisc_notify,
6411 		.maxlen		= sizeof(int),
6412 		.mode		= 0644,
6413 		.proc_handler	= proc_dointvec
6414 	},
6415 	{
6416 		.procname	= "suppress_frag_ndisc",
6417 		.data		= &ipv6_devconf.suppress_frag_ndisc,
6418 		.maxlen		= sizeof(int),
6419 		.mode		= 0644,
6420 		.proc_handler	= proc_dointvec
6421 	},
6422 	{
6423 		.procname	= "accept_ra_from_local",
6424 		.data		= &ipv6_devconf.accept_ra_from_local,
6425 		.maxlen		= sizeof(int),
6426 		.mode		= 0644,
6427 		.proc_handler	= proc_dointvec,
6428 	},
6429 	{
6430 		.procname	= "accept_ra_mtu",
6431 		.data		= &ipv6_devconf.accept_ra_mtu,
6432 		.maxlen		= sizeof(int),
6433 		.mode		= 0644,
6434 		.proc_handler	= proc_dointvec,
6435 	},
6436 	{
6437 		.procname	= "stable_secret",
6438 		.data		= &ipv6_devconf.stable_secret,
6439 		.maxlen		= IPV6_MAX_STRLEN,
6440 		.mode		= 0600,
6441 		.proc_handler	= addrconf_sysctl_stable_secret,
6442 	},
6443 	{
6444 		.procname	= "use_oif_addrs_only",
6445 		.data		= &ipv6_devconf.use_oif_addrs_only,
6446 		.maxlen		= sizeof(int),
6447 		.mode		= 0644,
6448 		.proc_handler	= proc_dointvec,
6449 	},
6450 	{
6451 		.procname	= "ignore_routes_with_linkdown",
6452 		.data		= &ipv6_devconf.ignore_routes_with_linkdown,
6453 		.maxlen		= sizeof(int),
6454 		.mode		= 0644,
6455 		.proc_handler	= addrconf_sysctl_ignore_routes_with_linkdown,
6456 	},
6457 	{
6458 		.procname	= "drop_unicast_in_l2_multicast",
6459 		.data		= &ipv6_devconf.drop_unicast_in_l2_multicast,
6460 		.maxlen		= sizeof(int),
6461 		.mode		= 0644,
6462 		.proc_handler	= proc_dointvec,
6463 	},
6464 	{
6465 		.procname	= "drop_unsolicited_na",
6466 		.data		= &ipv6_devconf.drop_unsolicited_na,
6467 		.maxlen		= sizeof(int),
6468 		.mode		= 0644,
6469 		.proc_handler	= proc_dointvec,
6470 	},
6471 	{
6472 		.procname	= "keep_addr_on_down",
6473 		.data		= &ipv6_devconf.keep_addr_on_down,
6474 		.maxlen		= sizeof(int),
6475 		.mode		= 0644,
6476 		.proc_handler	= proc_dointvec,
6477 
6478 	},
6479 	{
6480 		.procname	= "seg6_enabled",
6481 		.data		= &ipv6_devconf.seg6_enabled,
6482 		.maxlen		= sizeof(int),
6483 		.mode		= 0644,
6484 		.proc_handler	= proc_dointvec,
6485 	},
6486 #ifdef CONFIG_IPV6_SEG6_HMAC
6487 	{
6488 		.procname	= "seg6_require_hmac",
6489 		.data		= &ipv6_devconf.seg6_require_hmac,
6490 		.maxlen		= sizeof(int),
6491 		.mode		= 0644,
6492 		.proc_handler	= proc_dointvec,
6493 	},
6494 #endif
6495 	{
6496 		.procname       = "enhanced_dad",
6497 		.data           = &ipv6_devconf.enhanced_dad,
6498 		.maxlen         = sizeof(int),
6499 		.mode           = 0644,
6500 		.proc_handler   = proc_dointvec,
6501 	},
6502 	{
6503 		.procname		= "addr_gen_mode",
6504 		.data			= &ipv6_devconf.addr_gen_mode,
6505 		.maxlen			= sizeof(int),
6506 		.mode			= 0644,
6507 		.proc_handler	= addrconf_sysctl_addr_gen_mode,
6508 	},
6509 	{
6510 		.procname       = "disable_policy",
6511 		.data           = &ipv6_devconf.disable_policy,
6512 		.maxlen         = sizeof(int),
6513 		.mode           = 0644,
6514 		.proc_handler   = addrconf_sysctl_disable_policy,
6515 	},
6516 	{
6517 		.procname	= "ndisc_tclass",
6518 		.data		= &ipv6_devconf.ndisc_tclass,
6519 		.maxlen		= sizeof(int),
6520 		.mode		= 0644,
6521 		.proc_handler	= proc_dointvec_minmax,
6522 		.extra1		= (void *)&zero,
6523 		.extra2		= (void *)&two_five_five,
6524 	},
6525 	{
6526 		/* sentinel */
6527 	}
6528 };
6529 
6530 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
6531 		struct inet6_dev *idev, struct ipv6_devconf *p)
6532 {
6533 	int i, ifindex;
6534 	struct ctl_table *table;
6535 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
6536 
6537 	table = kmemdup(addrconf_sysctl, sizeof(addrconf_sysctl), GFP_KERNEL);
6538 	if (!table)
6539 		goto out;
6540 
6541 	for (i = 0; table[i].data; i++) {
6542 		table[i].data += (char *)p - (char *)&ipv6_devconf;
6543 		/* If one of these is already set, then it is not safe to
6544 		 * overwrite either of them: this makes proc_dointvec_minmax
6545 		 * usable.
6546 		 */
6547 		if (!table[i].extra1 && !table[i].extra2) {
6548 			table[i].extra1 = idev; /* embedded; no ref */
6549 			table[i].extra2 = net;
6550 		}
6551 	}
6552 
6553 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
6554 
6555 	p->sysctl_header = register_net_sysctl(net, path, table);
6556 	if (!p->sysctl_header)
6557 		goto free;
6558 
6559 	if (!strcmp(dev_name, "all"))
6560 		ifindex = NETCONFA_IFINDEX_ALL;
6561 	else if (!strcmp(dev_name, "default"))
6562 		ifindex = NETCONFA_IFINDEX_DEFAULT;
6563 	else
6564 		ifindex = idev->dev->ifindex;
6565 	inet6_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL,
6566 				     ifindex, p);
6567 	return 0;
6568 
6569 free:
6570 	kfree(table);
6571 out:
6572 	return -ENOBUFS;
6573 }
6574 
6575 static void __addrconf_sysctl_unregister(struct net *net,
6576 					 struct ipv6_devconf *p, int ifindex)
6577 {
6578 	struct ctl_table *table;
6579 
6580 	if (!p->sysctl_header)
6581 		return;
6582 
6583 	table = p->sysctl_header->ctl_table_arg;
6584 	unregister_net_sysctl_table(p->sysctl_header);
6585 	p->sysctl_header = NULL;
6586 	kfree(table);
6587 
6588 	inet6_netconf_notify_devconf(net, RTM_DELNETCONF, 0, ifindex, NULL);
6589 }
6590 
6591 static int addrconf_sysctl_register(struct inet6_dev *idev)
6592 {
6593 	int err;
6594 
6595 	if (!sysctl_dev_name_is_allowed(idev->dev->name))
6596 		return -EINVAL;
6597 
6598 	err = neigh_sysctl_register(idev->dev, idev->nd_parms,
6599 				    &ndisc_ifinfo_sysctl_change);
6600 	if (err)
6601 		return err;
6602 	err = __addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
6603 					 idev, &idev->cnf);
6604 	if (err)
6605 		neigh_sysctl_unregister(idev->nd_parms);
6606 
6607 	return err;
6608 }
6609 
6610 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
6611 {
6612 	__addrconf_sysctl_unregister(dev_net(idev->dev), &idev->cnf,
6613 				     idev->dev->ifindex);
6614 	neigh_sysctl_unregister(idev->nd_parms);
6615 }
6616 
6617 
6618 #endif
6619 
6620 static int __net_init addrconf_init_net(struct net *net)
6621 {
6622 	int err = -ENOMEM;
6623 	struct ipv6_devconf *all, *dflt;
6624 
6625 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
6626 	if (!all)
6627 		goto err_alloc_all;
6628 
6629 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
6630 	if (!dflt)
6631 		goto err_alloc_dflt;
6632 
6633 	/* these will be inherited by all namespaces */
6634 	dflt->autoconf = ipv6_defaults.autoconf;
6635 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
6636 
6637 	dflt->stable_secret.initialized = false;
6638 	all->stable_secret.initialized = false;
6639 
6640 	net->ipv6.devconf_all = all;
6641 	net->ipv6.devconf_dflt = dflt;
6642 
6643 #ifdef CONFIG_SYSCTL
6644 	err = __addrconf_sysctl_register(net, "all", NULL, all);
6645 	if (err < 0)
6646 		goto err_reg_all;
6647 
6648 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
6649 	if (err < 0)
6650 		goto err_reg_dflt;
6651 #endif
6652 	return 0;
6653 
6654 #ifdef CONFIG_SYSCTL
6655 err_reg_dflt:
6656 	__addrconf_sysctl_unregister(net, all, NETCONFA_IFINDEX_ALL);
6657 err_reg_all:
6658 	kfree(dflt);
6659 #endif
6660 err_alloc_dflt:
6661 	kfree(all);
6662 err_alloc_all:
6663 	return err;
6664 }
6665 
6666 static void __net_exit addrconf_exit_net(struct net *net)
6667 {
6668 #ifdef CONFIG_SYSCTL
6669 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_dflt,
6670 				     NETCONFA_IFINDEX_DEFAULT);
6671 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_all,
6672 				     NETCONFA_IFINDEX_ALL);
6673 #endif
6674 	kfree(net->ipv6.devconf_dflt);
6675 	kfree(net->ipv6.devconf_all);
6676 }
6677 
6678 static struct pernet_operations addrconf_ops = {
6679 	.init = addrconf_init_net,
6680 	.exit = addrconf_exit_net,
6681 };
6682 
6683 static struct rtnl_af_ops inet6_ops __read_mostly = {
6684 	.family		  = AF_INET6,
6685 	.fill_link_af	  = inet6_fill_link_af,
6686 	.get_link_af_size = inet6_get_link_af_size,
6687 	.validate_link_af = inet6_validate_link_af,
6688 	.set_link_af	  = inet6_set_link_af,
6689 };
6690 
6691 /*
6692  *	Init / cleanup code
6693  */
6694 
6695 int __init addrconf_init(void)
6696 {
6697 	struct inet6_dev *idev;
6698 	int i, err;
6699 
6700 	err = ipv6_addr_label_init();
6701 	if (err < 0) {
6702 		pr_crit("%s: cannot initialize default policy table: %d\n",
6703 			__func__, err);
6704 		goto out;
6705 	}
6706 
6707 	err = register_pernet_subsys(&addrconf_ops);
6708 	if (err < 0)
6709 		goto out_addrlabel;
6710 
6711 	addrconf_wq = create_workqueue("ipv6_addrconf");
6712 	if (!addrconf_wq) {
6713 		err = -ENOMEM;
6714 		goto out_nowq;
6715 	}
6716 
6717 	/* The addrconf netdev notifier requires that loopback_dev
6718 	 * has it's ipv6 private information allocated and setup
6719 	 * before it can bring up and give link-local addresses
6720 	 * to other devices which are up.
6721 	 *
6722 	 * Unfortunately, loopback_dev is not necessarily the first
6723 	 * entry in the global dev_base list of net devices.  In fact,
6724 	 * it is likely to be the very last entry on that list.
6725 	 * So this causes the notifier registry below to try and
6726 	 * give link-local addresses to all devices besides loopback_dev
6727 	 * first, then loopback_dev, which cases all the non-loopback_dev
6728 	 * devices to fail to get a link-local address.
6729 	 *
6730 	 * So, as a temporary fix, allocate the ipv6 structure for
6731 	 * loopback_dev first by hand.
6732 	 * Longer term, all of the dependencies ipv6 has upon the loopback
6733 	 * device and it being up should be removed.
6734 	 */
6735 	rtnl_lock();
6736 	idev = ipv6_add_dev(init_net.loopback_dev);
6737 	rtnl_unlock();
6738 	if (IS_ERR(idev)) {
6739 		err = PTR_ERR(idev);
6740 		goto errlo;
6741 	}
6742 
6743 	ip6_route_init_special_entries();
6744 
6745 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
6746 		INIT_HLIST_HEAD(&inet6_addr_lst[i]);
6747 
6748 	register_netdevice_notifier(&ipv6_dev_notf);
6749 
6750 	addrconf_verify();
6751 
6752 	rtnl_af_register(&inet6_ops);
6753 
6754 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETLINK,
6755 				   NULL, inet6_dump_ifinfo, 0);
6756 	if (err < 0)
6757 		goto errout;
6758 
6759 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_NEWADDR,
6760 				   inet6_rtm_newaddr, NULL, 0);
6761 	if (err < 0)
6762 		goto errout;
6763 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_DELADDR,
6764 				   inet6_rtm_deladdr, NULL, 0);
6765 	if (err < 0)
6766 		goto errout;
6767 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETADDR,
6768 				   inet6_rtm_getaddr, inet6_dump_ifaddr,
6769 				   RTNL_FLAG_DOIT_UNLOCKED);
6770 	if (err < 0)
6771 		goto errout;
6772 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETMULTICAST,
6773 				   NULL, inet6_dump_ifmcaddr, 0);
6774 	if (err < 0)
6775 		goto errout;
6776 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETANYCAST,
6777 				   NULL, inet6_dump_ifacaddr, 0);
6778 	if (err < 0)
6779 		goto errout;
6780 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETNETCONF,
6781 				   inet6_netconf_get_devconf,
6782 				   inet6_netconf_dump_devconf,
6783 				   RTNL_FLAG_DOIT_UNLOCKED);
6784 	if (err < 0)
6785 		goto errout;
6786 	err = ipv6_addr_label_rtnl_register();
6787 	if (err < 0)
6788 		goto errout;
6789 
6790 	return 0;
6791 errout:
6792 	rtnl_unregister_all(PF_INET6);
6793 	rtnl_af_unregister(&inet6_ops);
6794 	unregister_netdevice_notifier(&ipv6_dev_notf);
6795 errlo:
6796 	destroy_workqueue(addrconf_wq);
6797 out_nowq:
6798 	unregister_pernet_subsys(&addrconf_ops);
6799 out_addrlabel:
6800 	ipv6_addr_label_cleanup();
6801 out:
6802 	return err;
6803 }
6804 
6805 void addrconf_cleanup(void)
6806 {
6807 	struct net_device *dev;
6808 	int i;
6809 
6810 	unregister_netdevice_notifier(&ipv6_dev_notf);
6811 	unregister_pernet_subsys(&addrconf_ops);
6812 	ipv6_addr_label_cleanup();
6813 
6814 	rtnl_af_unregister(&inet6_ops);
6815 
6816 	rtnl_lock();
6817 
6818 	/* clean dev list */
6819 	for_each_netdev(&init_net, dev) {
6820 		if (__in6_dev_get(dev) == NULL)
6821 			continue;
6822 		addrconf_ifdown(dev, 1);
6823 	}
6824 	addrconf_ifdown(init_net.loopback_dev, 2);
6825 
6826 	/*
6827 	 *	Check hash table.
6828 	 */
6829 	spin_lock_bh(&addrconf_hash_lock);
6830 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
6831 		WARN_ON(!hlist_empty(&inet6_addr_lst[i]));
6832 	spin_unlock_bh(&addrconf_hash_lock);
6833 	cancel_delayed_work(&addr_chk_work);
6834 	rtnl_unlock();
6835 
6836 	destroy_workqueue(addrconf_wq);
6837 }
6838