xref: /openbmc/linux/net/ipv6/addrconf.c (revision f8e17c17)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *	IPv6 Address [auto]configuration
4  *	Linux INET6 implementation
5  *
6  *	Authors:
7  *	Pedro Roque		<roque@di.fc.ul.pt>
8  *	Alexey Kuznetsov	<kuznet@ms2.inr.ac.ru>
9  */
10 
11 /*
12  *	Changes:
13  *
14  *	Janos Farkas			:	delete timer on ifdown
15  *	<chexum@bankinf.banki.hu>
16  *	Andi Kleen			:	kill double kfree on module
17  *						unload.
18  *	Maciej W. Rozycki		:	FDDI support
19  *	sekiya@USAGI			:	Don't send too many RS
20  *						packets.
21  *	yoshfuji@USAGI			:       Fixed interval between DAD
22  *						packets.
23  *	YOSHIFUJI Hideaki @USAGI	:	improved accuracy of
24  *						address validation timer.
25  *	YOSHIFUJI Hideaki @USAGI	:	Privacy Extensions (RFC3041)
26  *						support.
27  *	Yuji SEKIYA @USAGI		:	Don't assign a same IPv6
28  *						address on a same interface.
29  *	YOSHIFUJI Hideaki @USAGI	:	ARCnet support
30  *	YOSHIFUJI Hideaki @USAGI	:	convert /proc/net/if_inet6 to
31  *						seq_file.
32  *	YOSHIFUJI Hideaki @USAGI	:	improved source address
33  *						selection; consider scope,
34  *						status etc.
35  */
36 
37 #define pr_fmt(fmt) "IPv6: " fmt
38 
39 #include <linux/errno.h>
40 #include <linux/types.h>
41 #include <linux/kernel.h>
42 #include <linux/sched/signal.h>
43 #include <linux/socket.h>
44 #include <linux/sockios.h>
45 #include <linux/net.h>
46 #include <linux/inet.h>
47 #include <linux/in6.h>
48 #include <linux/netdevice.h>
49 #include <linux/if_addr.h>
50 #include <linux/if_arp.h>
51 #include <linux/if_arcnet.h>
52 #include <linux/if_infiniband.h>
53 #include <linux/route.h>
54 #include <linux/inetdevice.h>
55 #include <linux/init.h>
56 #include <linux/slab.h>
57 #ifdef CONFIG_SYSCTL
58 #include <linux/sysctl.h>
59 #endif
60 #include <linux/capability.h>
61 #include <linux/delay.h>
62 #include <linux/notifier.h>
63 #include <linux/string.h>
64 #include <linux/hash.h>
65 
66 #include <net/net_namespace.h>
67 #include <net/sock.h>
68 #include <net/snmp.h>
69 
70 #include <net/6lowpan.h>
71 #include <net/firewire.h>
72 #include <net/ipv6.h>
73 #include <net/protocol.h>
74 #include <net/ndisc.h>
75 #include <net/ip6_route.h>
76 #include <net/addrconf.h>
77 #include <net/tcp.h>
78 #include <net/ip.h>
79 #include <net/netlink.h>
80 #include <net/pkt_sched.h>
81 #include <net/l3mdev.h>
82 #include <linux/if_tunnel.h>
83 #include <linux/rtnetlink.h>
84 #include <linux/netconf.h>
85 #include <linux/random.h>
86 #include <linux/uaccess.h>
87 #include <asm/unaligned.h>
88 
89 #include <linux/proc_fs.h>
90 #include <linux/seq_file.h>
91 #include <linux/export.h>
92 
93 #define	INFINITY_LIFE_TIME	0xFFFFFFFF
94 
95 #define IPV6_MAX_STRLEN \
96 	sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255")
97 
98 static inline u32 cstamp_delta(unsigned long cstamp)
99 {
100 	return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
101 }
102 
103 static inline s32 rfc3315_s14_backoff_init(s32 irt)
104 {
105 	/* multiply 'initial retransmission time' by 0.9 .. 1.1 */
106 	u64 tmp = (900000 + prandom_u32() % 200001) * (u64)irt;
107 	do_div(tmp, 1000000);
108 	return (s32)tmp;
109 }
110 
111 static inline s32 rfc3315_s14_backoff_update(s32 rt, s32 mrt)
112 {
113 	/* multiply 'retransmission timeout' by 1.9 .. 2.1 */
114 	u64 tmp = (1900000 + prandom_u32() % 200001) * (u64)rt;
115 	do_div(tmp, 1000000);
116 	if ((s32)tmp > mrt) {
117 		/* multiply 'maximum retransmission time' by 0.9 .. 1.1 */
118 		tmp = (900000 + prandom_u32() % 200001) * (u64)mrt;
119 		do_div(tmp, 1000000);
120 	}
121 	return (s32)tmp;
122 }
123 
124 #ifdef CONFIG_SYSCTL
125 static int addrconf_sysctl_register(struct inet6_dev *idev);
126 static void addrconf_sysctl_unregister(struct inet6_dev *idev);
127 #else
128 static inline int addrconf_sysctl_register(struct inet6_dev *idev)
129 {
130 	return 0;
131 }
132 
133 static inline void addrconf_sysctl_unregister(struct inet6_dev *idev)
134 {
135 }
136 #endif
137 
138 static void ipv6_regen_rndid(struct inet6_dev *idev);
139 static void ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr);
140 
141 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev);
142 static int ipv6_count_addresses(const struct inet6_dev *idev);
143 static int ipv6_generate_stable_address(struct in6_addr *addr,
144 					u8 dad_count,
145 					const struct inet6_dev *idev);
146 
147 #define IN6_ADDR_HSIZE_SHIFT	8
148 #define IN6_ADDR_HSIZE		(1 << IN6_ADDR_HSIZE_SHIFT)
149 /*
150  *	Configured unicast address hash table
151  */
152 static struct hlist_head inet6_addr_lst[IN6_ADDR_HSIZE];
153 static DEFINE_SPINLOCK(addrconf_hash_lock);
154 
155 static void addrconf_verify(void);
156 static void addrconf_verify_rtnl(void);
157 static void addrconf_verify_work(struct work_struct *);
158 
159 static struct workqueue_struct *addrconf_wq;
160 static DECLARE_DELAYED_WORK(addr_chk_work, addrconf_verify_work);
161 
162 static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
163 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
164 
165 static void addrconf_type_change(struct net_device *dev,
166 				 unsigned long event);
167 static int addrconf_ifdown(struct net_device *dev, int how);
168 
169 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
170 						  int plen,
171 						  const struct net_device *dev,
172 						  u32 flags, u32 noflags,
173 						  bool no_gw);
174 
175 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
176 static void addrconf_dad_work(struct work_struct *w);
177 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
178 				   bool send_na);
179 static void addrconf_dad_run(struct inet6_dev *idev, bool restart);
180 static void addrconf_rs_timer(struct timer_list *t);
181 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
182 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
183 
184 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
185 				struct prefix_info *pinfo);
186 
187 static struct ipv6_devconf ipv6_devconf __read_mostly = {
188 	.forwarding		= 0,
189 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
190 	.mtu6			= IPV6_MIN_MTU,
191 	.accept_ra		= 1,
192 	.accept_redirects	= 1,
193 	.autoconf		= 1,
194 	.force_mld_version	= 0,
195 	.mldv1_unsolicited_report_interval = 10 * HZ,
196 	.mldv2_unsolicited_report_interval = HZ,
197 	.dad_transmits		= 1,
198 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
199 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
200 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
201 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
202 	.use_tempaddr		= 0,
203 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
204 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
205 	.regen_max_retry	= REGEN_MAX_RETRY,
206 	.max_desync_factor	= MAX_DESYNC_FACTOR,
207 	.max_addresses		= IPV6_MAX_ADDRESSES,
208 	.accept_ra_defrtr	= 1,
209 	.accept_ra_from_local	= 0,
210 	.accept_ra_min_hop_limit= 1,
211 	.accept_ra_pinfo	= 1,
212 #ifdef CONFIG_IPV6_ROUTER_PREF
213 	.accept_ra_rtr_pref	= 1,
214 	.rtr_probe_interval	= 60 * HZ,
215 #ifdef CONFIG_IPV6_ROUTE_INFO
216 	.accept_ra_rt_info_min_plen = 0,
217 	.accept_ra_rt_info_max_plen = 0,
218 #endif
219 #endif
220 	.proxy_ndp		= 0,
221 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
222 	.disable_ipv6		= 0,
223 	.accept_dad		= 0,
224 	.suppress_frag_ndisc	= 1,
225 	.accept_ra_mtu		= 1,
226 	.stable_secret		= {
227 		.initialized = false,
228 	},
229 	.use_oif_addrs_only	= 0,
230 	.ignore_routes_with_linkdown = 0,
231 	.keep_addr_on_down	= 0,
232 	.seg6_enabled		= 0,
233 #ifdef CONFIG_IPV6_SEG6_HMAC
234 	.seg6_require_hmac	= 0,
235 #endif
236 	.enhanced_dad           = 1,
237 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
238 	.disable_policy		= 0,
239 };
240 
241 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
242 	.forwarding		= 0,
243 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
244 	.mtu6			= IPV6_MIN_MTU,
245 	.accept_ra		= 1,
246 	.accept_redirects	= 1,
247 	.autoconf		= 1,
248 	.force_mld_version	= 0,
249 	.mldv1_unsolicited_report_interval = 10 * HZ,
250 	.mldv2_unsolicited_report_interval = HZ,
251 	.dad_transmits		= 1,
252 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
253 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
254 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
255 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
256 	.use_tempaddr		= 0,
257 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
258 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
259 	.regen_max_retry	= REGEN_MAX_RETRY,
260 	.max_desync_factor	= MAX_DESYNC_FACTOR,
261 	.max_addresses		= IPV6_MAX_ADDRESSES,
262 	.accept_ra_defrtr	= 1,
263 	.accept_ra_from_local	= 0,
264 	.accept_ra_min_hop_limit= 1,
265 	.accept_ra_pinfo	= 1,
266 #ifdef CONFIG_IPV6_ROUTER_PREF
267 	.accept_ra_rtr_pref	= 1,
268 	.rtr_probe_interval	= 60 * HZ,
269 #ifdef CONFIG_IPV6_ROUTE_INFO
270 	.accept_ra_rt_info_min_plen = 0,
271 	.accept_ra_rt_info_max_plen = 0,
272 #endif
273 #endif
274 	.proxy_ndp		= 0,
275 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
276 	.disable_ipv6		= 0,
277 	.accept_dad		= 1,
278 	.suppress_frag_ndisc	= 1,
279 	.accept_ra_mtu		= 1,
280 	.stable_secret		= {
281 		.initialized = false,
282 	},
283 	.use_oif_addrs_only	= 0,
284 	.ignore_routes_with_linkdown = 0,
285 	.keep_addr_on_down	= 0,
286 	.seg6_enabled		= 0,
287 #ifdef CONFIG_IPV6_SEG6_HMAC
288 	.seg6_require_hmac	= 0,
289 #endif
290 	.enhanced_dad           = 1,
291 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
292 	.disable_policy		= 0,
293 };
294 
295 /* Check if link is ready: is it up and is a valid qdisc available */
296 static inline bool addrconf_link_ready(const struct net_device *dev)
297 {
298 	return netif_oper_up(dev) && !qdisc_tx_is_noop(dev);
299 }
300 
301 static void addrconf_del_rs_timer(struct inet6_dev *idev)
302 {
303 	if (del_timer(&idev->rs_timer))
304 		__in6_dev_put(idev);
305 }
306 
307 static void addrconf_del_dad_work(struct inet6_ifaddr *ifp)
308 {
309 	if (cancel_delayed_work(&ifp->dad_work))
310 		__in6_ifa_put(ifp);
311 }
312 
313 static void addrconf_mod_rs_timer(struct inet6_dev *idev,
314 				  unsigned long when)
315 {
316 	if (!timer_pending(&idev->rs_timer))
317 		in6_dev_hold(idev);
318 	mod_timer(&idev->rs_timer, jiffies + when);
319 }
320 
321 static void addrconf_mod_dad_work(struct inet6_ifaddr *ifp,
322 				   unsigned long delay)
323 {
324 	in6_ifa_hold(ifp);
325 	if (mod_delayed_work(addrconf_wq, &ifp->dad_work, delay))
326 		in6_ifa_put(ifp);
327 }
328 
329 static int snmp6_alloc_dev(struct inet6_dev *idev)
330 {
331 	int i;
332 
333 	idev->stats.ipv6 = alloc_percpu(struct ipstats_mib);
334 	if (!idev->stats.ipv6)
335 		goto err_ip;
336 
337 	for_each_possible_cpu(i) {
338 		struct ipstats_mib *addrconf_stats;
339 		addrconf_stats = per_cpu_ptr(idev->stats.ipv6, i);
340 		u64_stats_init(&addrconf_stats->syncp);
341 	}
342 
343 
344 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
345 					GFP_KERNEL);
346 	if (!idev->stats.icmpv6dev)
347 		goto err_icmp;
348 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
349 					   GFP_KERNEL);
350 	if (!idev->stats.icmpv6msgdev)
351 		goto err_icmpmsg;
352 
353 	return 0;
354 
355 err_icmpmsg:
356 	kfree(idev->stats.icmpv6dev);
357 err_icmp:
358 	free_percpu(idev->stats.ipv6);
359 err_ip:
360 	return -ENOMEM;
361 }
362 
363 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
364 {
365 	struct inet6_dev *ndev;
366 	int err = -ENOMEM;
367 
368 	ASSERT_RTNL();
369 
370 	if (dev->mtu < IPV6_MIN_MTU)
371 		return ERR_PTR(-EINVAL);
372 
373 	ndev = kzalloc(sizeof(struct inet6_dev), GFP_KERNEL);
374 	if (!ndev)
375 		return ERR_PTR(err);
376 
377 	rwlock_init(&ndev->lock);
378 	ndev->dev = dev;
379 	INIT_LIST_HEAD(&ndev->addr_list);
380 	timer_setup(&ndev->rs_timer, addrconf_rs_timer, 0);
381 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
382 
383 	if (ndev->cnf.stable_secret.initialized)
384 		ndev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
385 
386 	ndev->cnf.mtu6 = dev->mtu;
387 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
388 	if (!ndev->nd_parms) {
389 		kfree(ndev);
390 		return ERR_PTR(err);
391 	}
392 	if (ndev->cnf.forwarding)
393 		dev_disable_lro(dev);
394 	/* We refer to the device */
395 	dev_hold(dev);
396 
397 	if (snmp6_alloc_dev(ndev) < 0) {
398 		netdev_dbg(dev, "%s: cannot allocate memory for statistics\n",
399 			   __func__);
400 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
401 		dev_put(dev);
402 		kfree(ndev);
403 		return ERR_PTR(err);
404 	}
405 
406 	if (snmp6_register_dev(ndev) < 0) {
407 		netdev_dbg(dev, "%s: cannot create /proc/net/dev_snmp6/%s\n",
408 			   __func__, dev->name);
409 		goto err_release;
410 	}
411 
412 	/* One reference from device. */
413 	refcount_set(&ndev->refcnt, 1);
414 
415 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
416 		ndev->cnf.accept_dad = -1;
417 
418 #if IS_ENABLED(CONFIG_IPV6_SIT)
419 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
420 		pr_info("%s: Disabled Multicast RS\n", dev->name);
421 		ndev->cnf.rtr_solicits = 0;
422 	}
423 #endif
424 
425 	INIT_LIST_HEAD(&ndev->tempaddr_list);
426 	ndev->desync_factor = U32_MAX;
427 	if ((dev->flags&IFF_LOOPBACK) ||
428 	    dev->type == ARPHRD_TUNNEL ||
429 	    dev->type == ARPHRD_TUNNEL6 ||
430 	    dev->type == ARPHRD_SIT ||
431 	    dev->type == ARPHRD_NONE) {
432 		ndev->cnf.use_tempaddr = -1;
433 	} else
434 		ipv6_regen_rndid(ndev);
435 
436 	ndev->token = in6addr_any;
437 
438 	if (netif_running(dev) && addrconf_link_ready(dev))
439 		ndev->if_flags |= IF_READY;
440 
441 	ipv6_mc_init_dev(ndev);
442 	ndev->tstamp = jiffies;
443 	err = addrconf_sysctl_register(ndev);
444 	if (err) {
445 		ipv6_mc_destroy_dev(ndev);
446 		snmp6_unregister_dev(ndev);
447 		goto err_release;
448 	}
449 	/* protected by rtnl_lock */
450 	rcu_assign_pointer(dev->ip6_ptr, ndev);
451 
452 	/* Join interface-local all-node multicast group */
453 	ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes);
454 
455 	/* Join all-node multicast group */
456 	ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
457 
458 	/* Join all-router multicast group if forwarding is set */
459 	if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
460 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
461 
462 	return ndev;
463 
464 err_release:
465 	neigh_parms_release(&nd_tbl, ndev->nd_parms);
466 	ndev->dead = 1;
467 	in6_dev_finish_destroy(ndev);
468 	return ERR_PTR(err);
469 }
470 
471 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
472 {
473 	struct inet6_dev *idev;
474 
475 	ASSERT_RTNL();
476 
477 	idev = __in6_dev_get(dev);
478 	if (!idev) {
479 		idev = ipv6_add_dev(dev);
480 		if (IS_ERR(idev))
481 			return idev;
482 	}
483 
484 	if (dev->flags&IFF_UP)
485 		ipv6_mc_up(idev);
486 	return idev;
487 }
488 
489 static int inet6_netconf_msgsize_devconf(int type)
490 {
491 	int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
492 		    + nla_total_size(4);	/* NETCONFA_IFINDEX */
493 	bool all = false;
494 
495 	if (type == NETCONFA_ALL)
496 		all = true;
497 
498 	if (all || type == NETCONFA_FORWARDING)
499 		size += nla_total_size(4);
500 #ifdef CONFIG_IPV6_MROUTE
501 	if (all || type == NETCONFA_MC_FORWARDING)
502 		size += nla_total_size(4);
503 #endif
504 	if (all || type == NETCONFA_PROXY_NEIGH)
505 		size += nla_total_size(4);
506 
507 	if (all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN)
508 		size += nla_total_size(4);
509 
510 	return size;
511 }
512 
513 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
514 				      struct ipv6_devconf *devconf, u32 portid,
515 				      u32 seq, int event, unsigned int flags,
516 				      int type)
517 {
518 	struct nlmsghdr  *nlh;
519 	struct netconfmsg *ncm;
520 	bool all = false;
521 
522 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
523 			flags);
524 	if (!nlh)
525 		return -EMSGSIZE;
526 
527 	if (type == NETCONFA_ALL)
528 		all = true;
529 
530 	ncm = nlmsg_data(nlh);
531 	ncm->ncm_family = AF_INET6;
532 
533 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
534 		goto nla_put_failure;
535 
536 	if (!devconf)
537 		goto out;
538 
539 	if ((all || type == NETCONFA_FORWARDING) &&
540 	    nla_put_s32(skb, NETCONFA_FORWARDING, devconf->forwarding) < 0)
541 		goto nla_put_failure;
542 #ifdef CONFIG_IPV6_MROUTE
543 	if ((all || type == NETCONFA_MC_FORWARDING) &&
544 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
545 			devconf->mc_forwarding) < 0)
546 		goto nla_put_failure;
547 #endif
548 	if ((all || type == NETCONFA_PROXY_NEIGH) &&
549 	    nla_put_s32(skb, NETCONFA_PROXY_NEIGH, devconf->proxy_ndp) < 0)
550 		goto nla_put_failure;
551 
552 	if ((all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN) &&
553 	    nla_put_s32(skb, NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
554 			devconf->ignore_routes_with_linkdown) < 0)
555 		goto nla_put_failure;
556 
557 out:
558 	nlmsg_end(skb, nlh);
559 	return 0;
560 
561 nla_put_failure:
562 	nlmsg_cancel(skb, nlh);
563 	return -EMSGSIZE;
564 }
565 
566 void inet6_netconf_notify_devconf(struct net *net, int event, int type,
567 				  int ifindex, struct ipv6_devconf *devconf)
568 {
569 	struct sk_buff *skb;
570 	int err = -ENOBUFS;
571 
572 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_KERNEL);
573 	if (!skb)
574 		goto errout;
575 
576 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
577 					 event, 0, type);
578 	if (err < 0) {
579 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
580 		WARN_ON(err == -EMSGSIZE);
581 		kfree_skb(skb);
582 		goto errout;
583 	}
584 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_KERNEL);
585 	return;
586 errout:
587 	rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
588 }
589 
590 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
591 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
592 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
593 	[NETCONFA_PROXY_NEIGH]	= { .len = sizeof(int) },
594 	[NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN]	= { .len = sizeof(int) },
595 };
596 
597 static int inet6_netconf_valid_get_req(struct sk_buff *skb,
598 				       const struct nlmsghdr *nlh,
599 				       struct nlattr **tb,
600 				       struct netlink_ext_ack *extack)
601 {
602 	int i, err;
603 
604 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(struct netconfmsg))) {
605 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for netconf get request");
606 		return -EINVAL;
607 	}
608 
609 	if (!netlink_strict_get_check(skb))
610 		return nlmsg_parse_deprecated(nlh, sizeof(struct netconfmsg),
611 					      tb, NETCONFA_MAX,
612 					      devconf_ipv6_policy, extack);
613 
614 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct netconfmsg),
615 					    tb, NETCONFA_MAX,
616 					    devconf_ipv6_policy, extack);
617 	if (err)
618 		return err;
619 
620 	for (i = 0; i <= NETCONFA_MAX; i++) {
621 		if (!tb[i])
622 			continue;
623 
624 		switch (i) {
625 		case NETCONFA_IFINDEX:
626 			break;
627 		default:
628 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in netconf get request");
629 			return -EINVAL;
630 		}
631 	}
632 
633 	return 0;
634 }
635 
636 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
637 				     struct nlmsghdr *nlh,
638 				     struct netlink_ext_ack *extack)
639 {
640 	struct net *net = sock_net(in_skb->sk);
641 	struct nlattr *tb[NETCONFA_MAX+1];
642 	struct inet6_dev *in6_dev = NULL;
643 	struct net_device *dev = NULL;
644 	struct sk_buff *skb;
645 	struct ipv6_devconf *devconf;
646 	int ifindex;
647 	int err;
648 
649 	err = inet6_netconf_valid_get_req(in_skb, nlh, tb, extack);
650 	if (err < 0)
651 		return err;
652 
653 	if (!tb[NETCONFA_IFINDEX])
654 		return -EINVAL;
655 
656 	err = -EINVAL;
657 	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
658 	switch (ifindex) {
659 	case NETCONFA_IFINDEX_ALL:
660 		devconf = net->ipv6.devconf_all;
661 		break;
662 	case NETCONFA_IFINDEX_DEFAULT:
663 		devconf = net->ipv6.devconf_dflt;
664 		break;
665 	default:
666 		dev = dev_get_by_index(net, ifindex);
667 		if (!dev)
668 			return -EINVAL;
669 		in6_dev = in6_dev_get(dev);
670 		if (!in6_dev)
671 			goto errout;
672 		devconf = &in6_dev->cnf;
673 		break;
674 	}
675 
676 	err = -ENOBUFS;
677 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(NETCONFA_ALL), GFP_KERNEL);
678 	if (!skb)
679 		goto errout;
680 
681 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
682 					 NETLINK_CB(in_skb).portid,
683 					 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
684 					 NETCONFA_ALL);
685 	if (err < 0) {
686 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
687 		WARN_ON(err == -EMSGSIZE);
688 		kfree_skb(skb);
689 		goto errout;
690 	}
691 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
692 errout:
693 	if (in6_dev)
694 		in6_dev_put(in6_dev);
695 	if (dev)
696 		dev_put(dev);
697 	return err;
698 }
699 
700 static int inet6_netconf_dump_devconf(struct sk_buff *skb,
701 				      struct netlink_callback *cb)
702 {
703 	const struct nlmsghdr *nlh = cb->nlh;
704 	struct net *net = sock_net(skb->sk);
705 	int h, s_h;
706 	int idx, s_idx;
707 	struct net_device *dev;
708 	struct inet6_dev *idev;
709 	struct hlist_head *head;
710 
711 	if (cb->strict_check) {
712 		struct netlink_ext_ack *extack = cb->extack;
713 		struct netconfmsg *ncm;
714 
715 		if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ncm))) {
716 			NL_SET_ERR_MSG_MOD(extack, "Invalid header for netconf dump request");
717 			return -EINVAL;
718 		}
719 
720 		if (nlmsg_attrlen(nlh, sizeof(*ncm))) {
721 			NL_SET_ERR_MSG_MOD(extack, "Invalid data after header in netconf dump request");
722 			return -EINVAL;
723 		}
724 	}
725 
726 	s_h = cb->args[0];
727 	s_idx = idx = cb->args[1];
728 
729 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
730 		idx = 0;
731 		head = &net->dev_index_head[h];
732 		rcu_read_lock();
733 		cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^
734 			  net->dev_base_seq;
735 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
736 			if (idx < s_idx)
737 				goto cont;
738 			idev = __in6_dev_get(dev);
739 			if (!idev)
740 				goto cont;
741 
742 			if (inet6_netconf_fill_devconf(skb, dev->ifindex,
743 						       &idev->cnf,
744 						       NETLINK_CB(cb->skb).portid,
745 						       nlh->nlmsg_seq,
746 						       RTM_NEWNETCONF,
747 						       NLM_F_MULTI,
748 						       NETCONFA_ALL) < 0) {
749 				rcu_read_unlock();
750 				goto done;
751 			}
752 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
753 cont:
754 			idx++;
755 		}
756 		rcu_read_unlock();
757 	}
758 	if (h == NETDEV_HASHENTRIES) {
759 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
760 					       net->ipv6.devconf_all,
761 					       NETLINK_CB(cb->skb).portid,
762 					       nlh->nlmsg_seq,
763 					       RTM_NEWNETCONF, NLM_F_MULTI,
764 					       NETCONFA_ALL) < 0)
765 			goto done;
766 		else
767 			h++;
768 	}
769 	if (h == NETDEV_HASHENTRIES + 1) {
770 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
771 					       net->ipv6.devconf_dflt,
772 					       NETLINK_CB(cb->skb).portid,
773 					       nlh->nlmsg_seq,
774 					       RTM_NEWNETCONF, NLM_F_MULTI,
775 					       NETCONFA_ALL) < 0)
776 			goto done;
777 		else
778 			h++;
779 	}
780 done:
781 	cb->args[0] = h;
782 	cb->args[1] = idx;
783 
784 	return skb->len;
785 }
786 
787 #ifdef CONFIG_SYSCTL
788 static void dev_forward_change(struct inet6_dev *idev)
789 {
790 	struct net_device *dev;
791 	struct inet6_ifaddr *ifa;
792 
793 	if (!idev)
794 		return;
795 	dev = idev->dev;
796 	if (idev->cnf.forwarding)
797 		dev_disable_lro(dev);
798 	if (dev->flags & IFF_MULTICAST) {
799 		if (idev->cnf.forwarding) {
800 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
801 			ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
802 			ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters);
803 		} else {
804 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
805 			ipv6_dev_mc_dec(dev, &in6addr_interfacelocal_allrouters);
806 			ipv6_dev_mc_dec(dev, &in6addr_sitelocal_allrouters);
807 		}
808 	}
809 
810 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
811 		if (ifa->flags&IFA_F_TENTATIVE)
812 			continue;
813 		if (idev->cnf.forwarding)
814 			addrconf_join_anycast(ifa);
815 		else
816 			addrconf_leave_anycast(ifa);
817 	}
818 	inet6_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
819 				     NETCONFA_FORWARDING,
820 				     dev->ifindex, &idev->cnf);
821 }
822 
823 
824 static void addrconf_forward_change(struct net *net, __s32 newf)
825 {
826 	struct net_device *dev;
827 	struct inet6_dev *idev;
828 
829 	for_each_netdev(net, dev) {
830 		idev = __in6_dev_get(dev);
831 		if (idev) {
832 			int changed = (!idev->cnf.forwarding) ^ (!newf);
833 			idev->cnf.forwarding = newf;
834 			if (changed)
835 				dev_forward_change(idev);
836 		}
837 	}
838 }
839 
840 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int newf)
841 {
842 	struct net *net;
843 	int old;
844 
845 	if (!rtnl_trylock())
846 		return restart_syscall();
847 
848 	net = (struct net *)table->extra2;
849 	old = *p;
850 	*p = newf;
851 
852 	if (p == &net->ipv6.devconf_dflt->forwarding) {
853 		if ((!newf) ^ (!old))
854 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
855 						     NETCONFA_FORWARDING,
856 						     NETCONFA_IFINDEX_DEFAULT,
857 						     net->ipv6.devconf_dflt);
858 		rtnl_unlock();
859 		return 0;
860 	}
861 
862 	if (p == &net->ipv6.devconf_all->forwarding) {
863 		int old_dflt = net->ipv6.devconf_dflt->forwarding;
864 
865 		net->ipv6.devconf_dflt->forwarding = newf;
866 		if ((!newf) ^ (!old_dflt))
867 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
868 						     NETCONFA_FORWARDING,
869 						     NETCONFA_IFINDEX_DEFAULT,
870 						     net->ipv6.devconf_dflt);
871 
872 		addrconf_forward_change(net, newf);
873 		if ((!newf) ^ (!old))
874 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
875 						     NETCONFA_FORWARDING,
876 						     NETCONFA_IFINDEX_ALL,
877 						     net->ipv6.devconf_all);
878 	} else if ((!newf) ^ (!old))
879 		dev_forward_change((struct inet6_dev *)table->extra1);
880 	rtnl_unlock();
881 
882 	if (newf)
883 		rt6_purge_dflt_routers(net);
884 	return 1;
885 }
886 
887 static void addrconf_linkdown_change(struct net *net, __s32 newf)
888 {
889 	struct net_device *dev;
890 	struct inet6_dev *idev;
891 
892 	for_each_netdev(net, dev) {
893 		idev = __in6_dev_get(dev);
894 		if (idev) {
895 			int changed = (!idev->cnf.ignore_routes_with_linkdown) ^ (!newf);
896 
897 			idev->cnf.ignore_routes_with_linkdown = newf;
898 			if (changed)
899 				inet6_netconf_notify_devconf(dev_net(dev),
900 							     RTM_NEWNETCONF,
901 							     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
902 							     dev->ifindex,
903 							     &idev->cnf);
904 		}
905 	}
906 }
907 
908 static int addrconf_fixup_linkdown(struct ctl_table *table, int *p, int newf)
909 {
910 	struct net *net;
911 	int old;
912 
913 	if (!rtnl_trylock())
914 		return restart_syscall();
915 
916 	net = (struct net *)table->extra2;
917 	old = *p;
918 	*p = newf;
919 
920 	if (p == &net->ipv6.devconf_dflt->ignore_routes_with_linkdown) {
921 		if ((!newf) ^ (!old))
922 			inet6_netconf_notify_devconf(net,
923 						     RTM_NEWNETCONF,
924 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
925 						     NETCONFA_IFINDEX_DEFAULT,
926 						     net->ipv6.devconf_dflt);
927 		rtnl_unlock();
928 		return 0;
929 	}
930 
931 	if (p == &net->ipv6.devconf_all->ignore_routes_with_linkdown) {
932 		net->ipv6.devconf_dflt->ignore_routes_with_linkdown = newf;
933 		addrconf_linkdown_change(net, newf);
934 		if ((!newf) ^ (!old))
935 			inet6_netconf_notify_devconf(net,
936 						     RTM_NEWNETCONF,
937 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
938 						     NETCONFA_IFINDEX_ALL,
939 						     net->ipv6.devconf_all);
940 	}
941 	rtnl_unlock();
942 
943 	return 1;
944 }
945 
946 #endif
947 
948 /* Nobody refers to this ifaddr, destroy it */
949 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
950 {
951 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
952 
953 #ifdef NET_REFCNT_DEBUG
954 	pr_debug("%s\n", __func__);
955 #endif
956 
957 	in6_dev_put(ifp->idev);
958 
959 	if (cancel_delayed_work(&ifp->dad_work))
960 		pr_notice("delayed DAD work was pending while freeing ifa=%p\n",
961 			  ifp);
962 
963 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
964 		pr_warn("Freeing alive inet6 address %p\n", ifp);
965 		return;
966 	}
967 
968 	kfree_rcu(ifp, rcu);
969 }
970 
971 static void
972 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
973 {
974 	struct list_head *p;
975 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
976 
977 	/*
978 	 * Each device address list is sorted in order of scope -
979 	 * global before linklocal.
980 	 */
981 	list_for_each(p, &idev->addr_list) {
982 		struct inet6_ifaddr *ifa
983 			= list_entry(p, struct inet6_ifaddr, if_list);
984 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
985 			break;
986 	}
987 
988 	list_add_tail_rcu(&ifp->if_list, p);
989 }
990 
991 static u32 inet6_addr_hash(const struct net *net, const struct in6_addr *addr)
992 {
993 	u32 val = ipv6_addr_hash(addr) ^ net_hash_mix(net);
994 
995 	return hash_32(val, IN6_ADDR_HSIZE_SHIFT);
996 }
997 
998 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
999 			       struct net_device *dev, unsigned int hash)
1000 {
1001 	struct inet6_ifaddr *ifp;
1002 
1003 	hlist_for_each_entry(ifp, &inet6_addr_lst[hash], addr_lst) {
1004 		if (!net_eq(dev_net(ifp->idev->dev), net))
1005 			continue;
1006 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1007 			if (!dev || ifp->idev->dev == dev)
1008 				return true;
1009 		}
1010 	}
1011 	return false;
1012 }
1013 
1014 static int ipv6_add_addr_hash(struct net_device *dev, struct inet6_ifaddr *ifa)
1015 {
1016 	unsigned int hash = inet6_addr_hash(dev_net(dev), &ifa->addr);
1017 	int err = 0;
1018 
1019 	spin_lock(&addrconf_hash_lock);
1020 
1021 	/* Ignore adding duplicate addresses on an interface */
1022 	if (ipv6_chk_same_addr(dev_net(dev), &ifa->addr, dev, hash)) {
1023 		netdev_dbg(dev, "ipv6_add_addr: already assigned\n");
1024 		err = -EEXIST;
1025 	} else {
1026 		hlist_add_head_rcu(&ifa->addr_lst, &inet6_addr_lst[hash]);
1027 	}
1028 
1029 	spin_unlock(&addrconf_hash_lock);
1030 
1031 	return err;
1032 }
1033 
1034 /* On success it returns ifp with increased reference count */
1035 
1036 static struct inet6_ifaddr *
1037 ipv6_add_addr(struct inet6_dev *idev, struct ifa6_config *cfg,
1038 	      bool can_block, struct netlink_ext_ack *extack)
1039 {
1040 	gfp_t gfp_flags = can_block ? GFP_KERNEL : GFP_ATOMIC;
1041 	int addr_type = ipv6_addr_type(cfg->pfx);
1042 	struct net *net = dev_net(idev->dev);
1043 	struct inet6_ifaddr *ifa = NULL;
1044 	struct fib6_info *f6i = NULL;
1045 	int err = 0;
1046 
1047 	if (addr_type == IPV6_ADDR_ANY ||
1048 	    (addr_type & IPV6_ADDR_MULTICAST &&
1049 	     !(cfg->ifa_flags & IFA_F_MCAUTOJOIN)) ||
1050 	    (!(idev->dev->flags & IFF_LOOPBACK) &&
1051 	     !netif_is_l3_master(idev->dev) &&
1052 	     addr_type & IPV6_ADDR_LOOPBACK))
1053 		return ERR_PTR(-EADDRNOTAVAIL);
1054 
1055 	if (idev->dead) {
1056 		err = -ENODEV;			/*XXX*/
1057 		goto out;
1058 	}
1059 
1060 	if (idev->cnf.disable_ipv6) {
1061 		err = -EACCES;
1062 		goto out;
1063 	}
1064 
1065 	/* validator notifier needs to be blocking;
1066 	 * do not call in atomic context
1067 	 */
1068 	if (can_block) {
1069 		struct in6_validator_info i6vi = {
1070 			.i6vi_addr = *cfg->pfx,
1071 			.i6vi_dev = idev,
1072 			.extack = extack,
1073 		};
1074 
1075 		err = inet6addr_validator_notifier_call_chain(NETDEV_UP, &i6vi);
1076 		err = notifier_to_errno(err);
1077 		if (err < 0)
1078 			goto out;
1079 	}
1080 
1081 	ifa = kzalloc(sizeof(*ifa), gfp_flags);
1082 	if (!ifa) {
1083 		err = -ENOBUFS;
1084 		goto out;
1085 	}
1086 
1087 	f6i = addrconf_f6i_alloc(net, idev, cfg->pfx, false, gfp_flags);
1088 	if (IS_ERR(f6i)) {
1089 		err = PTR_ERR(f6i);
1090 		f6i = NULL;
1091 		goto out;
1092 	}
1093 
1094 	if (net->ipv6.devconf_all->disable_policy ||
1095 	    idev->cnf.disable_policy)
1096 		f6i->dst_nopolicy = true;
1097 
1098 	neigh_parms_data_state_setall(idev->nd_parms);
1099 
1100 	ifa->addr = *cfg->pfx;
1101 	if (cfg->peer_pfx)
1102 		ifa->peer_addr = *cfg->peer_pfx;
1103 
1104 	spin_lock_init(&ifa->lock);
1105 	INIT_DELAYED_WORK(&ifa->dad_work, addrconf_dad_work);
1106 	INIT_HLIST_NODE(&ifa->addr_lst);
1107 	ifa->scope = cfg->scope;
1108 	ifa->prefix_len = cfg->plen;
1109 	ifa->rt_priority = cfg->rt_priority;
1110 	ifa->flags = cfg->ifa_flags;
1111 	/* No need to add the TENTATIVE flag for addresses with NODAD */
1112 	if (!(cfg->ifa_flags & IFA_F_NODAD))
1113 		ifa->flags |= IFA_F_TENTATIVE;
1114 	ifa->valid_lft = cfg->valid_lft;
1115 	ifa->prefered_lft = cfg->preferred_lft;
1116 	ifa->cstamp = ifa->tstamp = jiffies;
1117 	ifa->tokenized = false;
1118 
1119 	ifa->rt = f6i;
1120 
1121 	ifa->idev = idev;
1122 	in6_dev_hold(idev);
1123 
1124 	/* For caller */
1125 	refcount_set(&ifa->refcnt, 1);
1126 
1127 	rcu_read_lock_bh();
1128 
1129 	err = ipv6_add_addr_hash(idev->dev, ifa);
1130 	if (err < 0) {
1131 		rcu_read_unlock_bh();
1132 		goto out;
1133 	}
1134 
1135 	write_lock(&idev->lock);
1136 
1137 	/* Add to inet6_dev unicast addr list. */
1138 	ipv6_link_dev_addr(idev, ifa);
1139 
1140 	if (ifa->flags&IFA_F_TEMPORARY) {
1141 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
1142 		in6_ifa_hold(ifa);
1143 	}
1144 
1145 	in6_ifa_hold(ifa);
1146 	write_unlock(&idev->lock);
1147 
1148 	rcu_read_unlock_bh();
1149 
1150 	inet6addr_notifier_call_chain(NETDEV_UP, ifa);
1151 out:
1152 	if (unlikely(err < 0)) {
1153 		fib6_info_release(f6i);
1154 
1155 		if (ifa) {
1156 			if (ifa->idev)
1157 				in6_dev_put(ifa->idev);
1158 			kfree(ifa);
1159 		}
1160 		ifa = ERR_PTR(err);
1161 	}
1162 
1163 	return ifa;
1164 }
1165 
1166 enum cleanup_prefix_rt_t {
1167 	CLEANUP_PREFIX_RT_NOP,    /* no cleanup action for prefix route */
1168 	CLEANUP_PREFIX_RT_DEL,    /* delete the prefix route */
1169 	CLEANUP_PREFIX_RT_EXPIRE, /* update the lifetime of the prefix route */
1170 };
1171 
1172 /*
1173  * Check, whether the prefix for ifp would still need a prefix route
1174  * after deleting ifp. The function returns one of the CLEANUP_PREFIX_RT_*
1175  * constants.
1176  *
1177  * 1) we don't purge prefix if address was not permanent.
1178  *    prefix is managed by its own lifetime.
1179  * 2) we also don't purge, if the address was IFA_F_NOPREFIXROUTE.
1180  * 3) if there are no addresses, delete prefix.
1181  * 4) if there are still other permanent address(es),
1182  *    corresponding prefix is still permanent.
1183  * 5) if there are still other addresses with IFA_F_NOPREFIXROUTE,
1184  *    don't purge the prefix, assume user space is managing it.
1185  * 6) otherwise, update prefix lifetime to the
1186  *    longest valid lifetime among the corresponding
1187  *    addresses on the device.
1188  *    Note: subsequent RA will update lifetime.
1189  **/
1190 static enum cleanup_prefix_rt_t
1191 check_cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long *expires)
1192 {
1193 	struct inet6_ifaddr *ifa;
1194 	struct inet6_dev *idev = ifp->idev;
1195 	unsigned long lifetime;
1196 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_DEL;
1197 
1198 	*expires = jiffies;
1199 
1200 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
1201 		if (ifa == ifp)
1202 			continue;
1203 		if (ifa->prefix_len != ifp->prefix_len ||
1204 		    !ipv6_prefix_equal(&ifa->addr, &ifp->addr,
1205 				       ifp->prefix_len))
1206 			continue;
1207 		if (ifa->flags & (IFA_F_PERMANENT | IFA_F_NOPREFIXROUTE))
1208 			return CLEANUP_PREFIX_RT_NOP;
1209 
1210 		action = CLEANUP_PREFIX_RT_EXPIRE;
1211 
1212 		spin_lock(&ifa->lock);
1213 
1214 		lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
1215 		/*
1216 		 * Note: Because this address is
1217 		 * not permanent, lifetime <
1218 		 * LONG_MAX / HZ here.
1219 		 */
1220 		if (time_before(*expires, ifa->tstamp + lifetime * HZ))
1221 			*expires = ifa->tstamp + lifetime * HZ;
1222 		spin_unlock(&ifa->lock);
1223 	}
1224 
1225 	return action;
1226 }
1227 
1228 static void
1229 cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long expires, bool del_rt)
1230 {
1231 	struct fib6_info *f6i;
1232 
1233 	f6i = addrconf_get_prefix_route(&ifp->addr, ifp->prefix_len,
1234 					ifp->idev->dev, 0, RTF_DEFAULT, true);
1235 	if (f6i) {
1236 		if (del_rt)
1237 			ip6_del_rt(dev_net(ifp->idev->dev), f6i);
1238 		else {
1239 			if (!(f6i->fib6_flags & RTF_EXPIRES))
1240 				fib6_set_expires(f6i, expires);
1241 			fib6_info_release(f6i);
1242 		}
1243 	}
1244 }
1245 
1246 
1247 /* This function wants to get referenced ifp and releases it before return */
1248 
1249 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
1250 {
1251 	int state;
1252 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_NOP;
1253 	unsigned long expires;
1254 
1255 	ASSERT_RTNL();
1256 
1257 	spin_lock_bh(&ifp->lock);
1258 	state = ifp->state;
1259 	ifp->state = INET6_IFADDR_STATE_DEAD;
1260 	spin_unlock_bh(&ifp->lock);
1261 
1262 	if (state == INET6_IFADDR_STATE_DEAD)
1263 		goto out;
1264 
1265 	spin_lock_bh(&addrconf_hash_lock);
1266 	hlist_del_init_rcu(&ifp->addr_lst);
1267 	spin_unlock_bh(&addrconf_hash_lock);
1268 
1269 	write_lock_bh(&ifp->idev->lock);
1270 
1271 	if (ifp->flags&IFA_F_TEMPORARY) {
1272 		list_del(&ifp->tmp_list);
1273 		if (ifp->ifpub) {
1274 			in6_ifa_put(ifp->ifpub);
1275 			ifp->ifpub = NULL;
1276 		}
1277 		__in6_ifa_put(ifp);
1278 	}
1279 
1280 	if (ifp->flags & IFA_F_PERMANENT && !(ifp->flags & IFA_F_NOPREFIXROUTE))
1281 		action = check_cleanup_prefix_route(ifp, &expires);
1282 
1283 	list_del_rcu(&ifp->if_list);
1284 	__in6_ifa_put(ifp);
1285 
1286 	write_unlock_bh(&ifp->idev->lock);
1287 
1288 	addrconf_del_dad_work(ifp);
1289 
1290 	ipv6_ifa_notify(RTM_DELADDR, ifp);
1291 
1292 	inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);
1293 
1294 	if (action != CLEANUP_PREFIX_RT_NOP) {
1295 		cleanup_prefix_route(ifp, expires,
1296 			action == CLEANUP_PREFIX_RT_DEL);
1297 	}
1298 
1299 	/* clean up prefsrc entries */
1300 	rt6_remove_prefsrc(ifp);
1301 out:
1302 	in6_ifa_put(ifp);
1303 }
1304 
1305 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp,
1306 				struct inet6_ifaddr *ift,
1307 				bool block)
1308 {
1309 	struct inet6_dev *idev = ifp->idev;
1310 	struct in6_addr addr, *tmpaddr;
1311 	unsigned long tmp_tstamp, age;
1312 	unsigned long regen_advance;
1313 	struct ifa6_config cfg;
1314 	int ret = 0;
1315 	unsigned long now = jiffies;
1316 	long max_desync_factor;
1317 	s32 cnf_temp_preferred_lft;
1318 
1319 	write_lock_bh(&idev->lock);
1320 	if (ift) {
1321 		spin_lock_bh(&ift->lock);
1322 		memcpy(&addr.s6_addr[8], &ift->addr.s6_addr[8], 8);
1323 		spin_unlock_bh(&ift->lock);
1324 		tmpaddr = &addr;
1325 	} else {
1326 		tmpaddr = NULL;
1327 	}
1328 retry:
1329 	in6_dev_hold(idev);
1330 	if (idev->cnf.use_tempaddr <= 0) {
1331 		write_unlock_bh(&idev->lock);
1332 		pr_info("%s: use_tempaddr is disabled\n", __func__);
1333 		in6_dev_put(idev);
1334 		ret = -1;
1335 		goto out;
1336 	}
1337 	spin_lock_bh(&ifp->lock);
1338 	if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
1339 		idev->cnf.use_tempaddr = -1;	/*XXX*/
1340 		spin_unlock_bh(&ifp->lock);
1341 		write_unlock_bh(&idev->lock);
1342 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1343 			__func__);
1344 		in6_dev_put(idev);
1345 		ret = -1;
1346 		goto out;
1347 	}
1348 	in6_ifa_hold(ifp);
1349 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1350 	ipv6_try_regen_rndid(idev, tmpaddr);
1351 	memcpy(&addr.s6_addr[8], idev->rndid, 8);
1352 	age = (now - ifp->tstamp) / HZ;
1353 
1354 	regen_advance = idev->cnf.regen_max_retry *
1355 			idev->cnf.dad_transmits *
1356 			NEIGH_VAR(idev->nd_parms, RETRANS_TIME) / HZ;
1357 
1358 	/* recalculate max_desync_factor each time and update
1359 	 * idev->desync_factor if it's larger
1360 	 */
1361 	cnf_temp_preferred_lft = READ_ONCE(idev->cnf.temp_prefered_lft);
1362 	max_desync_factor = min_t(__u32,
1363 				  idev->cnf.max_desync_factor,
1364 				  cnf_temp_preferred_lft - regen_advance);
1365 
1366 	if (unlikely(idev->desync_factor > max_desync_factor)) {
1367 		if (max_desync_factor > 0) {
1368 			get_random_bytes(&idev->desync_factor,
1369 					 sizeof(idev->desync_factor));
1370 			idev->desync_factor %= max_desync_factor;
1371 		} else {
1372 			idev->desync_factor = 0;
1373 		}
1374 	}
1375 
1376 	memset(&cfg, 0, sizeof(cfg));
1377 	cfg.valid_lft = min_t(__u32, ifp->valid_lft,
1378 			      idev->cnf.temp_valid_lft + age);
1379 	cfg.preferred_lft = cnf_temp_preferred_lft + age - idev->desync_factor;
1380 	cfg.preferred_lft = min_t(__u32, ifp->prefered_lft, cfg.preferred_lft);
1381 
1382 	cfg.plen = ifp->prefix_len;
1383 	tmp_tstamp = ifp->tstamp;
1384 	spin_unlock_bh(&ifp->lock);
1385 
1386 	write_unlock_bh(&idev->lock);
1387 
1388 	/* A temporary address is created only if this calculated Preferred
1389 	 * Lifetime is greater than REGEN_ADVANCE time units.  In particular,
1390 	 * an implementation must not create a temporary address with a zero
1391 	 * Preferred Lifetime.
1392 	 * Use age calculation as in addrconf_verify to avoid unnecessary
1393 	 * temporary addresses being generated.
1394 	 */
1395 	age = (now - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
1396 	if (cfg.preferred_lft <= regen_advance + age) {
1397 		in6_ifa_put(ifp);
1398 		in6_dev_put(idev);
1399 		ret = -1;
1400 		goto out;
1401 	}
1402 
1403 	cfg.ifa_flags = IFA_F_TEMPORARY;
1404 	/* set in addrconf_prefix_rcv() */
1405 	if (ifp->flags & IFA_F_OPTIMISTIC)
1406 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
1407 
1408 	cfg.pfx = &addr;
1409 	cfg.scope = ipv6_addr_scope(cfg.pfx);
1410 
1411 	ift = ipv6_add_addr(idev, &cfg, block, NULL);
1412 	if (IS_ERR(ift)) {
1413 		in6_ifa_put(ifp);
1414 		in6_dev_put(idev);
1415 		pr_info("%s: retry temporary address regeneration\n", __func__);
1416 		tmpaddr = &addr;
1417 		write_lock_bh(&idev->lock);
1418 		goto retry;
1419 	}
1420 
1421 	spin_lock_bh(&ift->lock);
1422 	ift->ifpub = ifp;
1423 	ift->cstamp = now;
1424 	ift->tstamp = tmp_tstamp;
1425 	spin_unlock_bh(&ift->lock);
1426 
1427 	addrconf_dad_start(ift);
1428 	in6_ifa_put(ift);
1429 	in6_dev_put(idev);
1430 out:
1431 	return ret;
1432 }
1433 
1434 /*
1435  *	Choose an appropriate source address (RFC3484)
1436  */
1437 enum {
1438 	IPV6_SADDR_RULE_INIT = 0,
1439 	IPV6_SADDR_RULE_LOCAL,
1440 	IPV6_SADDR_RULE_SCOPE,
1441 	IPV6_SADDR_RULE_PREFERRED,
1442 #ifdef CONFIG_IPV6_MIP6
1443 	IPV6_SADDR_RULE_HOA,
1444 #endif
1445 	IPV6_SADDR_RULE_OIF,
1446 	IPV6_SADDR_RULE_LABEL,
1447 	IPV6_SADDR_RULE_PRIVACY,
1448 	IPV6_SADDR_RULE_ORCHID,
1449 	IPV6_SADDR_RULE_PREFIX,
1450 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1451 	IPV6_SADDR_RULE_NOT_OPTIMISTIC,
1452 #endif
1453 	IPV6_SADDR_RULE_MAX
1454 };
1455 
1456 struct ipv6_saddr_score {
1457 	int			rule;
1458 	int			addr_type;
1459 	struct inet6_ifaddr	*ifa;
1460 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1461 	int			scopedist;
1462 	int			matchlen;
1463 };
1464 
1465 struct ipv6_saddr_dst {
1466 	const struct in6_addr *addr;
1467 	int ifindex;
1468 	int scope;
1469 	int label;
1470 	unsigned int prefs;
1471 };
1472 
1473 static inline int ipv6_saddr_preferred(int type)
1474 {
1475 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1476 		return 1;
1477 	return 0;
1478 }
1479 
1480 static bool ipv6_use_optimistic_addr(struct net *net,
1481 				     struct inet6_dev *idev)
1482 {
1483 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1484 	if (!idev)
1485 		return false;
1486 	if (!net->ipv6.devconf_all->optimistic_dad && !idev->cnf.optimistic_dad)
1487 		return false;
1488 	if (!net->ipv6.devconf_all->use_optimistic && !idev->cnf.use_optimistic)
1489 		return false;
1490 
1491 	return true;
1492 #else
1493 	return false;
1494 #endif
1495 }
1496 
1497 static bool ipv6_allow_optimistic_dad(struct net *net,
1498 				      struct inet6_dev *idev)
1499 {
1500 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1501 	if (!idev)
1502 		return false;
1503 	if (!net->ipv6.devconf_all->optimistic_dad && !idev->cnf.optimistic_dad)
1504 		return false;
1505 
1506 	return true;
1507 #else
1508 	return false;
1509 #endif
1510 }
1511 
1512 static int ipv6_get_saddr_eval(struct net *net,
1513 			       struct ipv6_saddr_score *score,
1514 			       struct ipv6_saddr_dst *dst,
1515 			       int i)
1516 {
1517 	int ret;
1518 
1519 	if (i <= score->rule) {
1520 		switch (i) {
1521 		case IPV6_SADDR_RULE_SCOPE:
1522 			ret = score->scopedist;
1523 			break;
1524 		case IPV6_SADDR_RULE_PREFIX:
1525 			ret = score->matchlen;
1526 			break;
1527 		default:
1528 			ret = !!test_bit(i, score->scorebits);
1529 		}
1530 		goto out;
1531 	}
1532 
1533 	switch (i) {
1534 	case IPV6_SADDR_RULE_INIT:
1535 		/* Rule 0: remember if hiscore is not ready yet */
1536 		ret = !!score->ifa;
1537 		break;
1538 	case IPV6_SADDR_RULE_LOCAL:
1539 		/* Rule 1: Prefer same address */
1540 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1541 		break;
1542 	case IPV6_SADDR_RULE_SCOPE:
1543 		/* Rule 2: Prefer appropriate scope
1544 		 *
1545 		 *      ret
1546 		 *       ^
1547 		 *    -1 |  d 15
1548 		 *    ---+--+-+---> scope
1549 		 *       |
1550 		 *       |             d is scope of the destination.
1551 		 *  B-d  |  \
1552 		 *       |   \      <- smaller scope is better if
1553 		 *  B-15 |    \        if scope is enough for destination.
1554 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1555 		 * d-C-1 | /
1556 		 *       |/         <- greater is better
1557 		 *   -C  /             if scope is not enough for destination.
1558 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1559 		 *
1560 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1561 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1562 		 * Assume B = 0 and we get C > 29.
1563 		 */
1564 		ret = __ipv6_addr_src_scope(score->addr_type);
1565 		if (ret >= dst->scope)
1566 			ret = -ret;
1567 		else
1568 			ret -= 128;	/* 30 is enough */
1569 		score->scopedist = ret;
1570 		break;
1571 	case IPV6_SADDR_RULE_PREFERRED:
1572 	    {
1573 		/* Rule 3: Avoid deprecated and optimistic addresses */
1574 		u8 avoid = IFA_F_DEPRECATED;
1575 
1576 		if (!ipv6_use_optimistic_addr(net, score->ifa->idev))
1577 			avoid |= IFA_F_OPTIMISTIC;
1578 		ret = ipv6_saddr_preferred(score->addr_type) ||
1579 		      !(score->ifa->flags & avoid);
1580 		break;
1581 	    }
1582 #ifdef CONFIG_IPV6_MIP6
1583 	case IPV6_SADDR_RULE_HOA:
1584 	    {
1585 		/* Rule 4: Prefer home address */
1586 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1587 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1588 		break;
1589 	    }
1590 #endif
1591 	case IPV6_SADDR_RULE_OIF:
1592 		/* Rule 5: Prefer outgoing interface */
1593 		ret = (!dst->ifindex ||
1594 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1595 		break;
1596 	case IPV6_SADDR_RULE_LABEL:
1597 		/* Rule 6: Prefer matching label */
1598 		ret = ipv6_addr_label(net,
1599 				      &score->ifa->addr, score->addr_type,
1600 				      score->ifa->idev->dev->ifindex) == dst->label;
1601 		break;
1602 	case IPV6_SADDR_RULE_PRIVACY:
1603 	    {
1604 		/* Rule 7: Prefer public address
1605 		 * Note: prefer temporary address if use_tempaddr >= 2
1606 		 */
1607 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1608 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1609 				score->ifa->idev->cnf.use_tempaddr >= 2;
1610 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1611 		break;
1612 	    }
1613 	case IPV6_SADDR_RULE_ORCHID:
1614 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1615 		 *	    non-ORCHID vs non-ORCHID
1616 		 */
1617 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1618 			ipv6_addr_orchid(dst->addr));
1619 		break;
1620 	case IPV6_SADDR_RULE_PREFIX:
1621 		/* Rule 8: Use longest matching prefix */
1622 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1623 		if (ret > score->ifa->prefix_len)
1624 			ret = score->ifa->prefix_len;
1625 		score->matchlen = ret;
1626 		break;
1627 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1628 	case IPV6_SADDR_RULE_NOT_OPTIMISTIC:
1629 		/* Optimistic addresses still have lower precedence than other
1630 		 * preferred addresses.
1631 		 */
1632 		ret = !(score->ifa->flags & IFA_F_OPTIMISTIC);
1633 		break;
1634 #endif
1635 	default:
1636 		ret = 0;
1637 	}
1638 
1639 	if (ret)
1640 		__set_bit(i, score->scorebits);
1641 	score->rule = i;
1642 out:
1643 	return ret;
1644 }
1645 
1646 static int __ipv6_dev_get_saddr(struct net *net,
1647 				struct ipv6_saddr_dst *dst,
1648 				struct inet6_dev *idev,
1649 				struct ipv6_saddr_score *scores,
1650 				int hiscore_idx)
1651 {
1652 	struct ipv6_saddr_score *score = &scores[1 - hiscore_idx], *hiscore = &scores[hiscore_idx];
1653 
1654 	list_for_each_entry_rcu(score->ifa, &idev->addr_list, if_list) {
1655 		int i;
1656 
1657 		/*
1658 		 * - Tentative Address (RFC2462 section 5.4)
1659 		 *  - A tentative address is not considered
1660 		 *    "assigned to an interface" in the traditional
1661 		 *    sense, unless it is also flagged as optimistic.
1662 		 * - Candidate Source Address (section 4)
1663 		 *  - In any case, anycast addresses, multicast
1664 		 *    addresses, and the unspecified address MUST
1665 		 *    NOT be included in a candidate set.
1666 		 */
1667 		if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1668 		    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1669 			continue;
1670 
1671 		score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1672 
1673 		if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1674 			     score->addr_type & IPV6_ADDR_MULTICAST)) {
1675 			net_dbg_ratelimited("ADDRCONF: unspecified / multicast address assigned as unicast address on %s",
1676 					    idev->dev->name);
1677 			continue;
1678 		}
1679 
1680 		score->rule = -1;
1681 		bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1682 
1683 		for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1684 			int minihiscore, miniscore;
1685 
1686 			minihiscore = ipv6_get_saddr_eval(net, hiscore, dst, i);
1687 			miniscore = ipv6_get_saddr_eval(net, score, dst, i);
1688 
1689 			if (minihiscore > miniscore) {
1690 				if (i == IPV6_SADDR_RULE_SCOPE &&
1691 				    score->scopedist > 0) {
1692 					/*
1693 					 * special case:
1694 					 * each remaining entry
1695 					 * has too small (not enough)
1696 					 * scope, because ifa entries
1697 					 * are sorted by their scope
1698 					 * values.
1699 					 */
1700 					goto out;
1701 				}
1702 				break;
1703 			} else if (minihiscore < miniscore) {
1704 				swap(hiscore, score);
1705 				hiscore_idx = 1 - hiscore_idx;
1706 
1707 				/* restore our iterator */
1708 				score->ifa = hiscore->ifa;
1709 
1710 				break;
1711 			}
1712 		}
1713 	}
1714 out:
1715 	return hiscore_idx;
1716 }
1717 
1718 static int ipv6_get_saddr_master(struct net *net,
1719 				 const struct net_device *dst_dev,
1720 				 const struct net_device *master,
1721 				 struct ipv6_saddr_dst *dst,
1722 				 struct ipv6_saddr_score *scores,
1723 				 int hiscore_idx)
1724 {
1725 	struct inet6_dev *idev;
1726 
1727 	idev = __in6_dev_get(dst_dev);
1728 	if (idev)
1729 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1730 						   scores, hiscore_idx);
1731 
1732 	idev = __in6_dev_get(master);
1733 	if (idev)
1734 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1735 						   scores, hiscore_idx);
1736 
1737 	return hiscore_idx;
1738 }
1739 
1740 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1741 		       const struct in6_addr *daddr, unsigned int prefs,
1742 		       struct in6_addr *saddr)
1743 {
1744 	struct ipv6_saddr_score scores[2], *hiscore;
1745 	struct ipv6_saddr_dst dst;
1746 	struct inet6_dev *idev;
1747 	struct net_device *dev;
1748 	int dst_type;
1749 	bool use_oif_addr = false;
1750 	int hiscore_idx = 0;
1751 	int ret = 0;
1752 
1753 	dst_type = __ipv6_addr_type(daddr);
1754 	dst.addr = daddr;
1755 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1756 	dst.scope = __ipv6_addr_src_scope(dst_type);
1757 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1758 	dst.prefs = prefs;
1759 
1760 	scores[hiscore_idx].rule = -1;
1761 	scores[hiscore_idx].ifa = NULL;
1762 
1763 	rcu_read_lock();
1764 
1765 	/* Candidate Source Address (section 4)
1766 	 *  - multicast and link-local destination address,
1767 	 *    the set of candidate source address MUST only
1768 	 *    include addresses assigned to interfaces
1769 	 *    belonging to the same link as the outgoing
1770 	 *    interface.
1771 	 * (- For site-local destination addresses, the
1772 	 *    set of candidate source addresses MUST only
1773 	 *    include addresses assigned to interfaces
1774 	 *    belonging to the same site as the outgoing
1775 	 *    interface.)
1776 	 *  - "It is RECOMMENDED that the candidate source addresses
1777 	 *    be the set of unicast addresses assigned to the
1778 	 *    interface that will be used to send to the destination
1779 	 *    (the 'outgoing' interface)." (RFC 6724)
1780 	 */
1781 	if (dst_dev) {
1782 		idev = __in6_dev_get(dst_dev);
1783 		if ((dst_type & IPV6_ADDR_MULTICAST) ||
1784 		    dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL ||
1785 		    (idev && idev->cnf.use_oif_addrs_only)) {
1786 			use_oif_addr = true;
1787 		}
1788 	}
1789 
1790 	if (use_oif_addr) {
1791 		if (idev)
1792 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1793 	} else {
1794 		const struct net_device *master;
1795 		int master_idx = 0;
1796 
1797 		/* if dst_dev exists and is enslaved to an L3 device, then
1798 		 * prefer addresses from dst_dev and then the master over
1799 		 * any other enslaved devices in the L3 domain.
1800 		 */
1801 		master = l3mdev_master_dev_rcu(dst_dev);
1802 		if (master) {
1803 			master_idx = master->ifindex;
1804 
1805 			hiscore_idx = ipv6_get_saddr_master(net, dst_dev,
1806 							    master, &dst,
1807 							    scores, hiscore_idx);
1808 
1809 			if (scores[hiscore_idx].ifa)
1810 				goto out;
1811 		}
1812 
1813 		for_each_netdev_rcu(net, dev) {
1814 			/* only consider addresses on devices in the
1815 			 * same L3 domain
1816 			 */
1817 			if (l3mdev_master_ifindex_rcu(dev) != master_idx)
1818 				continue;
1819 			idev = __in6_dev_get(dev);
1820 			if (!idev)
1821 				continue;
1822 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1823 		}
1824 	}
1825 
1826 out:
1827 	hiscore = &scores[hiscore_idx];
1828 	if (!hiscore->ifa)
1829 		ret = -EADDRNOTAVAIL;
1830 	else
1831 		*saddr = hiscore->ifa->addr;
1832 
1833 	rcu_read_unlock();
1834 	return ret;
1835 }
1836 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1837 
1838 int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr,
1839 		      u32 banned_flags)
1840 {
1841 	struct inet6_ifaddr *ifp;
1842 	int err = -EADDRNOTAVAIL;
1843 
1844 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1845 		if (ifp->scope > IFA_LINK)
1846 			break;
1847 		if (ifp->scope == IFA_LINK &&
1848 		    !(ifp->flags & banned_flags)) {
1849 			*addr = ifp->addr;
1850 			err = 0;
1851 			break;
1852 		}
1853 	}
1854 	return err;
1855 }
1856 
1857 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1858 		    u32 banned_flags)
1859 {
1860 	struct inet6_dev *idev;
1861 	int err = -EADDRNOTAVAIL;
1862 
1863 	rcu_read_lock();
1864 	idev = __in6_dev_get(dev);
1865 	if (idev) {
1866 		read_lock_bh(&idev->lock);
1867 		err = __ipv6_get_lladdr(idev, addr, banned_flags);
1868 		read_unlock_bh(&idev->lock);
1869 	}
1870 	rcu_read_unlock();
1871 	return err;
1872 }
1873 
1874 static int ipv6_count_addresses(const struct inet6_dev *idev)
1875 {
1876 	const struct inet6_ifaddr *ifp;
1877 	int cnt = 0;
1878 
1879 	rcu_read_lock();
1880 	list_for_each_entry_rcu(ifp, &idev->addr_list, if_list)
1881 		cnt++;
1882 	rcu_read_unlock();
1883 	return cnt;
1884 }
1885 
1886 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1887 		  const struct net_device *dev, int strict)
1888 {
1889 	return ipv6_chk_addr_and_flags(net, addr, dev, !dev,
1890 				       strict, IFA_F_TENTATIVE);
1891 }
1892 EXPORT_SYMBOL(ipv6_chk_addr);
1893 
1894 /* device argument is used to find the L3 domain of interest. If
1895  * skip_dev_check is set, then the ifp device is not checked against
1896  * the passed in dev argument. So the 2 cases for addresses checks are:
1897  *   1. does the address exist in the L3 domain that dev is part of
1898  *      (skip_dev_check = true), or
1899  *
1900  *   2. does the address exist on the specific device
1901  *      (skip_dev_check = false)
1902  */
1903 int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
1904 			    const struct net_device *dev, bool skip_dev_check,
1905 			    int strict, u32 banned_flags)
1906 {
1907 	unsigned int hash = inet6_addr_hash(net, addr);
1908 	const struct net_device *l3mdev;
1909 	struct inet6_ifaddr *ifp;
1910 	u32 ifp_flags;
1911 
1912 	rcu_read_lock();
1913 
1914 	l3mdev = l3mdev_master_dev_rcu(dev);
1915 	if (skip_dev_check)
1916 		dev = NULL;
1917 
1918 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
1919 		if (!net_eq(dev_net(ifp->idev->dev), net))
1920 			continue;
1921 
1922 		if (l3mdev_master_dev_rcu(ifp->idev->dev) != l3mdev)
1923 			continue;
1924 
1925 		/* Decouple optimistic from tentative for evaluation here.
1926 		 * Ban optimistic addresses explicitly, when required.
1927 		 */
1928 		ifp_flags = (ifp->flags&IFA_F_OPTIMISTIC)
1929 			    ? (ifp->flags&~IFA_F_TENTATIVE)
1930 			    : ifp->flags;
1931 		if (ipv6_addr_equal(&ifp->addr, addr) &&
1932 		    !(ifp_flags&banned_flags) &&
1933 		    (!dev || ifp->idev->dev == dev ||
1934 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1935 			rcu_read_unlock();
1936 			return 1;
1937 		}
1938 	}
1939 
1940 	rcu_read_unlock();
1941 	return 0;
1942 }
1943 EXPORT_SYMBOL(ipv6_chk_addr_and_flags);
1944 
1945 
1946 /* Compares an address/prefix_len with addresses on device @dev.
1947  * If one is found it returns true.
1948  */
1949 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
1950 	const unsigned int prefix_len, struct net_device *dev)
1951 {
1952 	const struct inet6_ifaddr *ifa;
1953 	const struct inet6_dev *idev;
1954 	bool ret = false;
1955 
1956 	rcu_read_lock();
1957 	idev = __in6_dev_get(dev);
1958 	if (idev) {
1959 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
1960 			ret = ipv6_prefix_equal(addr, &ifa->addr, prefix_len);
1961 			if (ret)
1962 				break;
1963 		}
1964 	}
1965 	rcu_read_unlock();
1966 
1967 	return ret;
1968 }
1969 EXPORT_SYMBOL(ipv6_chk_custom_prefix);
1970 
1971 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
1972 {
1973 	const struct inet6_ifaddr *ifa;
1974 	const struct inet6_dev *idev;
1975 	int	onlink;
1976 
1977 	onlink = 0;
1978 	rcu_read_lock();
1979 	idev = __in6_dev_get(dev);
1980 	if (idev) {
1981 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
1982 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
1983 						   ifa->prefix_len);
1984 			if (onlink)
1985 				break;
1986 		}
1987 	}
1988 	rcu_read_unlock();
1989 	return onlink;
1990 }
1991 EXPORT_SYMBOL(ipv6_chk_prefix);
1992 
1993 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
1994 				     struct net_device *dev, int strict)
1995 {
1996 	unsigned int hash = inet6_addr_hash(net, addr);
1997 	struct inet6_ifaddr *ifp, *result = NULL;
1998 
1999 	rcu_read_lock();
2000 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
2001 		if (!net_eq(dev_net(ifp->idev->dev), net))
2002 			continue;
2003 		if (ipv6_addr_equal(&ifp->addr, addr)) {
2004 			if (!dev || ifp->idev->dev == dev ||
2005 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
2006 				result = ifp;
2007 				in6_ifa_hold(ifp);
2008 				break;
2009 			}
2010 		}
2011 	}
2012 	rcu_read_unlock();
2013 
2014 	return result;
2015 }
2016 
2017 /* Gets referenced address, destroys ifaddr */
2018 
2019 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
2020 {
2021 	if (dad_failed)
2022 		ifp->flags |= IFA_F_DADFAILED;
2023 
2024 	if (ifp->flags&IFA_F_TEMPORARY) {
2025 		struct inet6_ifaddr *ifpub;
2026 		spin_lock_bh(&ifp->lock);
2027 		ifpub = ifp->ifpub;
2028 		if (ifpub) {
2029 			in6_ifa_hold(ifpub);
2030 			spin_unlock_bh(&ifp->lock);
2031 			ipv6_create_tempaddr(ifpub, ifp, true);
2032 			in6_ifa_put(ifpub);
2033 		} else {
2034 			spin_unlock_bh(&ifp->lock);
2035 		}
2036 		ipv6_del_addr(ifp);
2037 	} else if (ifp->flags&IFA_F_PERMANENT || !dad_failed) {
2038 		spin_lock_bh(&ifp->lock);
2039 		addrconf_del_dad_work(ifp);
2040 		ifp->flags |= IFA_F_TENTATIVE;
2041 		if (dad_failed)
2042 			ifp->flags &= ~IFA_F_OPTIMISTIC;
2043 		spin_unlock_bh(&ifp->lock);
2044 		if (dad_failed)
2045 			ipv6_ifa_notify(0, ifp);
2046 		in6_ifa_put(ifp);
2047 	} else {
2048 		ipv6_del_addr(ifp);
2049 	}
2050 }
2051 
2052 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
2053 {
2054 	int err = -ENOENT;
2055 
2056 	spin_lock_bh(&ifp->lock);
2057 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
2058 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
2059 		err = 0;
2060 	}
2061 	spin_unlock_bh(&ifp->lock);
2062 
2063 	return err;
2064 }
2065 
2066 void addrconf_dad_failure(struct sk_buff *skb, struct inet6_ifaddr *ifp)
2067 {
2068 	struct inet6_dev *idev = ifp->idev;
2069 	struct net *net = dev_net(ifp->idev->dev);
2070 
2071 	if (addrconf_dad_end(ifp)) {
2072 		in6_ifa_put(ifp);
2073 		return;
2074 	}
2075 
2076 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c used by %pM detected!\n",
2077 			     ifp->idev->dev->name, &ifp->addr, eth_hdr(skb)->h_source);
2078 
2079 	spin_lock_bh(&ifp->lock);
2080 
2081 	if (ifp->flags & IFA_F_STABLE_PRIVACY) {
2082 		struct in6_addr new_addr;
2083 		struct inet6_ifaddr *ifp2;
2084 		int retries = ifp->stable_privacy_retry + 1;
2085 		struct ifa6_config cfg = {
2086 			.pfx = &new_addr,
2087 			.plen = ifp->prefix_len,
2088 			.ifa_flags = ifp->flags,
2089 			.valid_lft = ifp->valid_lft,
2090 			.preferred_lft = ifp->prefered_lft,
2091 			.scope = ifp->scope,
2092 		};
2093 
2094 		if (retries > net->ipv6.sysctl.idgen_retries) {
2095 			net_info_ratelimited("%s: privacy stable address generation failed because of DAD conflicts!\n",
2096 					     ifp->idev->dev->name);
2097 			goto errdad;
2098 		}
2099 
2100 		new_addr = ifp->addr;
2101 		if (ipv6_generate_stable_address(&new_addr, retries,
2102 						 idev))
2103 			goto errdad;
2104 
2105 		spin_unlock_bh(&ifp->lock);
2106 
2107 		if (idev->cnf.max_addresses &&
2108 		    ipv6_count_addresses(idev) >=
2109 		    idev->cnf.max_addresses)
2110 			goto lock_errdad;
2111 
2112 		net_info_ratelimited("%s: generating new stable privacy address because of DAD conflict\n",
2113 				     ifp->idev->dev->name);
2114 
2115 		ifp2 = ipv6_add_addr(idev, &cfg, false, NULL);
2116 		if (IS_ERR(ifp2))
2117 			goto lock_errdad;
2118 
2119 		spin_lock_bh(&ifp2->lock);
2120 		ifp2->stable_privacy_retry = retries;
2121 		ifp2->state = INET6_IFADDR_STATE_PREDAD;
2122 		spin_unlock_bh(&ifp2->lock);
2123 
2124 		addrconf_mod_dad_work(ifp2, net->ipv6.sysctl.idgen_delay);
2125 		in6_ifa_put(ifp2);
2126 lock_errdad:
2127 		spin_lock_bh(&ifp->lock);
2128 	}
2129 
2130 errdad:
2131 	/* transition from _POSTDAD to _ERRDAD */
2132 	ifp->state = INET6_IFADDR_STATE_ERRDAD;
2133 	spin_unlock_bh(&ifp->lock);
2134 
2135 	addrconf_mod_dad_work(ifp, 0);
2136 	in6_ifa_put(ifp);
2137 }
2138 
2139 /* Join to solicited addr multicast group.
2140  * caller must hold RTNL */
2141 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
2142 {
2143 	struct in6_addr maddr;
2144 
2145 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2146 		return;
2147 
2148 	addrconf_addr_solict_mult(addr, &maddr);
2149 	ipv6_dev_mc_inc(dev, &maddr);
2150 }
2151 
2152 /* caller must hold RTNL */
2153 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
2154 {
2155 	struct in6_addr maddr;
2156 
2157 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2158 		return;
2159 
2160 	addrconf_addr_solict_mult(addr, &maddr);
2161 	__ipv6_dev_mc_dec(idev, &maddr);
2162 }
2163 
2164 /* caller must hold RTNL */
2165 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
2166 {
2167 	struct in6_addr addr;
2168 
2169 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2170 		return;
2171 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2172 	if (ipv6_addr_any(&addr))
2173 		return;
2174 	__ipv6_dev_ac_inc(ifp->idev, &addr);
2175 }
2176 
2177 /* caller must hold RTNL */
2178 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
2179 {
2180 	struct in6_addr addr;
2181 
2182 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2183 		return;
2184 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2185 	if (ipv6_addr_any(&addr))
2186 		return;
2187 	__ipv6_dev_ac_dec(ifp->idev, &addr);
2188 }
2189 
2190 static int addrconf_ifid_6lowpan(u8 *eui, struct net_device *dev)
2191 {
2192 	switch (dev->addr_len) {
2193 	case ETH_ALEN:
2194 		memcpy(eui, dev->dev_addr, 3);
2195 		eui[3] = 0xFF;
2196 		eui[4] = 0xFE;
2197 		memcpy(eui + 5, dev->dev_addr + 3, 3);
2198 		break;
2199 	case EUI64_ADDR_LEN:
2200 		memcpy(eui, dev->dev_addr, EUI64_ADDR_LEN);
2201 		eui[0] ^= 2;
2202 		break;
2203 	default:
2204 		return -1;
2205 	}
2206 
2207 	return 0;
2208 }
2209 
2210 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
2211 {
2212 	union fwnet_hwaddr *ha;
2213 
2214 	if (dev->addr_len != FWNET_ALEN)
2215 		return -1;
2216 
2217 	ha = (union fwnet_hwaddr *)dev->dev_addr;
2218 
2219 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
2220 	eui[0] ^= 2;
2221 	return 0;
2222 }
2223 
2224 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
2225 {
2226 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
2227 	if (dev->addr_len != ARCNET_ALEN)
2228 		return -1;
2229 	memset(eui, 0, 7);
2230 	eui[7] = *(u8 *)dev->dev_addr;
2231 	return 0;
2232 }
2233 
2234 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
2235 {
2236 	if (dev->addr_len != INFINIBAND_ALEN)
2237 		return -1;
2238 	memcpy(eui, dev->dev_addr + 12, 8);
2239 	eui[0] |= 2;
2240 	return 0;
2241 }
2242 
2243 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
2244 {
2245 	if (addr == 0)
2246 		return -1;
2247 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
2248 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
2249 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
2250 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
2251 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
2252 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
2253 	eui[1] = 0;
2254 	eui[2] = 0x5E;
2255 	eui[3] = 0xFE;
2256 	memcpy(eui + 4, &addr, 4);
2257 	return 0;
2258 }
2259 
2260 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
2261 {
2262 	if (dev->priv_flags & IFF_ISATAP)
2263 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2264 	return -1;
2265 }
2266 
2267 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
2268 {
2269 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2270 }
2271 
2272 static int addrconf_ifid_ip6tnl(u8 *eui, struct net_device *dev)
2273 {
2274 	memcpy(eui, dev->perm_addr, 3);
2275 	memcpy(eui + 5, dev->perm_addr + 3, 3);
2276 	eui[3] = 0xFF;
2277 	eui[4] = 0xFE;
2278 	eui[0] ^= 2;
2279 	return 0;
2280 }
2281 
2282 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
2283 {
2284 	switch (dev->type) {
2285 	case ARPHRD_ETHER:
2286 	case ARPHRD_FDDI:
2287 		return addrconf_ifid_eui48(eui, dev);
2288 	case ARPHRD_ARCNET:
2289 		return addrconf_ifid_arcnet(eui, dev);
2290 	case ARPHRD_INFINIBAND:
2291 		return addrconf_ifid_infiniband(eui, dev);
2292 	case ARPHRD_SIT:
2293 		return addrconf_ifid_sit(eui, dev);
2294 	case ARPHRD_IPGRE:
2295 	case ARPHRD_TUNNEL:
2296 		return addrconf_ifid_gre(eui, dev);
2297 	case ARPHRD_6LOWPAN:
2298 		return addrconf_ifid_6lowpan(eui, dev);
2299 	case ARPHRD_IEEE1394:
2300 		return addrconf_ifid_ieee1394(eui, dev);
2301 	case ARPHRD_TUNNEL6:
2302 	case ARPHRD_IP6GRE:
2303 	case ARPHRD_RAWIP:
2304 		return addrconf_ifid_ip6tnl(eui, dev);
2305 	}
2306 	return -1;
2307 }
2308 
2309 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
2310 {
2311 	int err = -1;
2312 	struct inet6_ifaddr *ifp;
2313 
2314 	read_lock_bh(&idev->lock);
2315 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
2316 		if (ifp->scope > IFA_LINK)
2317 			break;
2318 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
2319 			memcpy(eui, ifp->addr.s6_addr+8, 8);
2320 			err = 0;
2321 			break;
2322 		}
2323 	}
2324 	read_unlock_bh(&idev->lock);
2325 	return err;
2326 }
2327 
2328 /* (re)generation of randomized interface identifier (RFC 3041 3.2, 3.5) */
2329 static void ipv6_regen_rndid(struct inet6_dev *idev)
2330 {
2331 regen:
2332 	get_random_bytes(idev->rndid, sizeof(idev->rndid));
2333 	idev->rndid[0] &= ~0x02;
2334 
2335 	/*
2336 	 * <draft-ietf-ipngwg-temp-addresses-v2-00.txt>:
2337 	 * check if generated address is not inappropriate
2338 	 *
2339 	 *  - Reserved subnet anycast (RFC 2526)
2340 	 *	11111101 11....11 1xxxxxxx
2341 	 *  - ISATAP (RFC4214) 6.1
2342 	 *	00-00-5E-FE-xx-xx-xx-xx
2343 	 *  - value 0
2344 	 *  - XXX: already assigned to an address on the device
2345 	 */
2346 	if (idev->rndid[0] == 0xfd &&
2347 	    (idev->rndid[1]&idev->rndid[2]&idev->rndid[3]&idev->rndid[4]&idev->rndid[5]&idev->rndid[6]) == 0xff &&
2348 	    (idev->rndid[7]&0x80))
2349 		goto regen;
2350 	if ((idev->rndid[0]|idev->rndid[1]) == 0) {
2351 		if (idev->rndid[2] == 0x5e && idev->rndid[3] == 0xfe)
2352 			goto regen;
2353 		if ((idev->rndid[2]|idev->rndid[3]|idev->rndid[4]|idev->rndid[5]|idev->rndid[6]|idev->rndid[7]) == 0x00)
2354 			goto regen;
2355 	}
2356 }
2357 
2358 static void  ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr)
2359 {
2360 	if (tmpaddr && memcmp(idev->rndid, &tmpaddr->s6_addr[8], 8) == 0)
2361 		ipv6_regen_rndid(idev);
2362 }
2363 
2364 /*
2365  *	Add prefix route.
2366  */
2367 
2368 static void
2369 addrconf_prefix_route(struct in6_addr *pfx, int plen, u32 metric,
2370 		      struct net_device *dev, unsigned long expires,
2371 		      u32 flags, gfp_t gfp_flags)
2372 {
2373 	struct fib6_config cfg = {
2374 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX,
2375 		.fc_metric = metric ? : IP6_RT_PRIO_ADDRCONF,
2376 		.fc_ifindex = dev->ifindex,
2377 		.fc_expires = expires,
2378 		.fc_dst_len = plen,
2379 		.fc_flags = RTF_UP | flags,
2380 		.fc_nlinfo.nl_net = dev_net(dev),
2381 		.fc_protocol = RTPROT_KERNEL,
2382 		.fc_type = RTN_UNICAST,
2383 	};
2384 
2385 	cfg.fc_dst = *pfx;
2386 
2387 	/* Prevent useless cloning on PtP SIT.
2388 	   This thing is done here expecting that the whole
2389 	   class of non-broadcast devices need not cloning.
2390 	 */
2391 #if IS_ENABLED(CONFIG_IPV6_SIT)
2392 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
2393 		cfg.fc_flags |= RTF_NONEXTHOP;
2394 #endif
2395 
2396 	ip6_route_add(&cfg, gfp_flags, NULL);
2397 }
2398 
2399 
2400 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
2401 						  int plen,
2402 						  const struct net_device *dev,
2403 						  u32 flags, u32 noflags,
2404 						  bool no_gw)
2405 {
2406 	struct fib6_node *fn;
2407 	struct fib6_info *rt = NULL;
2408 	struct fib6_table *table;
2409 	u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX;
2410 
2411 	table = fib6_get_table(dev_net(dev), tb_id);
2412 	if (!table)
2413 		return NULL;
2414 
2415 	rcu_read_lock();
2416 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0, true);
2417 	if (!fn)
2418 		goto out;
2419 
2420 	for_each_fib6_node_rt_rcu(fn) {
2421 		/* prefix routes only use builtin fib6_nh */
2422 		if (rt->nh)
2423 			continue;
2424 
2425 		if (rt->fib6_nh->fib_nh_dev->ifindex != dev->ifindex)
2426 			continue;
2427 		if (no_gw && rt->fib6_nh->fib_nh_gw_family)
2428 			continue;
2429 		if ((rt->fib6_flags & flags) != flags)
2430 			continue;
2431 		if ((rt->fib6_flags & noflags) != 0)
2432 			continue;
2433 		if (!fib6_info_hold_safe(rt))
2434 			continue;
2435 		break;
2436 	}
2437 out:
2438 	rcu_read_unlock();
2439 	return rt;
2440 }
2441 
2442 
2443 /* Create "default" multicast route to the interface */
2444 
2445 static void addrconf_add_mroute(struct net_device *dev)
2446 {
2447 	struct fib6_config cfg = {
2448 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_LOCAL,
2449 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2450 		.fc_ifindex = dev->ifindex,
2451 		.fc_dst_len = 8,
2452 		.fc_flags = RTF_UP,
2453 		.fc_type = RTN_UNICAST,
2454 		.fc_nlinfo.nl_net = dev_net(dev),
2455 	};
2456 
2457 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
2458 
2459 	ip6_route_add(&cfg, GFP_KERNEL, NULL);
2460 }
2461 
2462 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2463 {
2464 	struct inet6_dev *idev;
2465 
2466 	ASSERT_RTNL();
2467 
2468 	idev = ipv6_find_idev(dev);
2469 	if (IS_ERR(idev))
2470 		return idev;
2471 
2472 	if (idev->cnf.disable_ipv6)
2473 		return ERR_PTR(-EACCES);
2474 
2475 	/* Add default multicast route */
2476 	if (!(dev->flags & IFF_LOOPBACK) && !netif_is_l3_master(dev))
2477 		addrconf_add_mroute(dev);
2478 
2479 	return idev;
2480 }
2481 
2482 static void manage_tempaddrs(struct inet6_dev *idev,
2483 			     struct inet6_ifaddr *ifp,
2484 			     __u32 valid_lft, __u32 prefered_lft,
2485 			     bool create, unsigned long now)
2486 {
2487 	u32 flags;
2488 	struct inet6_ifaddr *ift;
2489 
2490 	read_lock_bh(&idev->lock);
2491 	/* update all temporary addresses in the list */
2492 	list_for_each_entry(ift, &idev->tempaddr_list, tmp_list) {
2493 		int age, max_valid, max_prefered;
2494 
2495 		if (ifp != ift->ifpub)
2496 			continue;
2497 
2498 		/* RFC 4941 section 3.3:
2499 		 * If a received option will extend the lifetime of a public
2500 		 * address, the lifetimes of temporary addresses should
2501 		 * be extended, subject to the overall constraint that no
2502 		 * temporary addresses should ever remain "valid" or "preferred"
2503 		 * for a time longer than (TEMP_VALID_LIFETIME) or
2504 		 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR), respectively.
2505 		 */
2506 		age = (now - ift->cstamp) / HZ;
2507 		max_valid = idev->cnf.temp_valid_lft - age;
2508 		if (max_valid < 0)
2509 			max_valid = 0;
2510 
2511 		max_prefered = idev->cnf.temp_prefered_lft -
2512 			       idev->desync_factor - age;
2513 		if (max_prefered < 0)
2514 			max_prefered = 0;
2515 
2516 		if (valid_lft > max_valid)
2517 			valid_lft = max_valid;
2518 
2519 		if (prefered_lft > max_prefered)
2520 			prefered_lft = max_prefered;
2521 
2522 		spin_lock(&ift->lock);
2523 		flags = ift->flags;
2524 		ift->valid_lft = valid_lft;
2525 		ift->prefered_lft = prefered_lft;
2526 		ift->tstamp = now;
2527 		if (prefered_lft > 0)
2528 			ift->flags &= ~IFA_F_DEPRECATED;
2529 
2530 		spin_unlock(&ift->lock);
2531 		if (!(flags&IFA_F_TENTATIVE))
2532 			ipv6_ifa_notify(0, ift);
2533 	}
2534 
2535 	if ((create || list_empty(&idev->tempaddr_list)) &&
2536 	    idev->cnf.use_tempaddr > 0) {
2537 		/* When a new public address is created as described
2538 		 * in [ADDRCONF], also create a new temporary address.
2539 		 * Also create a temporary address if it's enabled but
2540 		 * no temporary address currently exists.
2541 		 */
2542 		read_unlock_bh(&idev->lock);
2543 		ipv6_create_tempaddr(ifp, NULL, false);
2544 	} else {
2545 		read_unlock_bh(&idev->lock);
2546 	}
2547 }
2548 
2549 static bool is_addr_mode_generate_stable(struct inet6_dev *idev)
2550 {
2551 	return idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY ||
2552 	       idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_RANDOM;
2553 }
2554 
2555 int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
2556 				 const struct prefix_info *pinfo,
2557 				 struct inet6_dev *in6_dev,
2558 				 const struct in6_addr *addr, int addr_type,
2559 				 u32 addr_flags, bool sllao, bool tokenized,
2560 				 __u32 valid_lft, u32 prefered_lft)
2561 {
2562 	struct inet6_ifaddr *ifp = ipv6_get_ifaddr(net, addr, dev, 1);
2563 	int create = 0, update_lft = 0;
2564 
2565 	if (!ifp && valid_lft) {
2566 		int max_addresses = in6_dev->cnf.max_addresses;
2567 		struct ifa6_config cfg = {
2568 			.pfx = addr,
2569 			.plen = pinfo->prefix_len,
2570 			.ifa_flags = addr_flags,
2571 			.valid_lft = valid_lft,
2572 			.preferred_lft = prefered_lft,
2573 			.scope = addr_type & IPV6_ADDR_SCOPE_MASK,
2574 		};
2575 
2576 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2577 		if ((net->ipv6.devconf_all->optimistic_dad ||
2578 		     in6_dev->cnf.optimistic_dad) &&
2579 		    !net->ipv6.devconf_all->forwarding && sllao)
2580 			cfg.ifa_flags |= IFA_F_OPTIMISTIC;
2581 #endif
2582 
2583 		/* Do not allow to create too much of autoconfigured
2584 		 * addresses; this would be too easy way to crash kernel.
2585 		 */
2586 		if (!max_addresses ||
2587 		    ipv6_count_addresses(in6_dev) < max_addresses)
2588 			ifp = ipv6_add_addr(in6_dev, &cfg, false, NULL);
2589 
2590 		if (IS_ERR_OR_NULL(ifp))
2591 			return -1;
2592 
2593 		create = 1;
2594 		spin_lock_bh(&ifp->lock);
2595 		ifp->flags |= IFA_F_MANAGETEMPADDR;
2596 		ifp->cstamp = jiffies;
2597 		ifp->tokenized = tokenized;
2598 		spin_unlock_bh(&ifp->lock);
2599 		addrconf_dad_start(ifp);
2600 	}
2601 
2602 	if (ifp) {
2603 		u32 flags;
2604 		unsigned long now;
2605 		u32 stored_lft;
2606 
2607 		/* update lifetime (RFC2462 5.5.3 e) */
2608 		spin_lock_bh(&ifp->lock);
2609 		now = jiffies;
2610 		if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2611 			stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2612 		else
2613 			stored_lft = 0;
2614 		if (!create && stored_lft) {
2615 			const u32 minimum_lft = min_t(u32,
2616 				stored_lft, MIN_VALID_LIFETIME);
2617 			valid_lft = max(valid_lft, minimum_lft);
2618 
2619 			/* RFC4862 Section 5.5.3e:
2620 			 * "Note that the preferred lifetime of the
2621 			 *  corresponding address is always reset to
2622 			 *  the Preferred Lifetime in the received
2623 			 *  Prefix Information option, regardless of
2624 			 *  whether the valid lifetime is also reset or
2625 			 *  ignored."
2626 			 *
2627 			 * So we should always update prefered_lft here.
2628 			 */
2629 			update_lft = 1;
2630 		}
2631 
2632 		if (update_lft) {
2633 			ifp->valid_lft = valid_lft;
2634 			ifp->prefered_lft = prefered_lft;
2635 			ifp->tstamp = now;
2636 			flags = ifp->flags;
2637 			ifp->flags &= ~IFA_F_DEPRECATED;
2638 			spin_unlock_bh(&ifp->lock);
2639 
2640 			if (!(flags&IFA_F_TENTATIVE))
2641 				ipv6_ifa_notify(0, ifp);
2642 		} else
2643 			spin_unlock_bh(&ifp->lock);
2644 
2645 		manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
2646 				 create, now);
2647 
2648 		in6_ifa_put(ifp);
2649 		addrconf_verify();
2650 	}
2651 
2652 	return 0;
2653 }
2654 EXPORT_SYMBOL_GPL(addrconf_prefix_rcv_add_addr);
2655 
2656 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2657 {
2658 	struct prefix_info *pinfo;
2659 	__u32 valid_lft;
2660 	__u32 prefered_lft;
2661 	int addr_type, err;
2662 	u32 addr_flags = 0;
2663 	struct inet6_dev *in6_dev;
2664 	struct net *net = dev_net(dev);
2665 
2666 	pinfo = (struct prefix_info *) opt;
2667 
2668 	if (len < sizeof(struct prefix_info)) {
2669 		netdev_dbg(dev, "addrconf: prefix option too short\n");
2670 		return;
2671 	}
2672 
2673 	/*
2674 	 *	Validation checks ([ADDRCONF], page 19)
2675 	 */
2676 
2677 	addr_type = ipv6_addr_type(&pinfo->prefix);
2678 
2679 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2680 		return;
2681 
2682 	valid_lft = ntohl(pinfo->valid);
2683 	prefered_lft = ntohl(pinfo->prefered);
2684 
2685 	if (prefered_lft > valid_lft) {
2686 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2687 		return;
2688 	}
2689 
2690 	in6_dev = in6_dev_get(dev);
2691 
2692 	if (!in6_dev) {
2693 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2694 				    dev->name);
2695 		return;
2696 	}
2697 
2698 	/*
2699 	 *	Two things going on here:
2700 	 *	1) Add routes for on-link prefixes
2701 	 *	2) Configure prefixes with the auto flag set
2702 	 */
2703 
2704 	if (pinfo->onlink) {
2705 		struct fib6_info *rt;
2706 		unsigned long rt_expires;
2707 
2708 		/* Avoid arithmetic overflow. Really, we could
2709 		 * save rt_expires in seconds, likely valid_lft,
2710 		 * but it would require division in fib gc, that it
2711 		 * not good.
2712 		 */
2713 		if (HZ > USER_HZ)
2714 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2715 		else
2716 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2717 
2718 		if (addrconf_finite_timeout(rt_expires))
2719 			rt_expires *= HZ;
2720 
2721 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2722 					       pinfo->prefix_len,
2723 					       dev,
2724 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2725 					       RTF_DEFAULT, true);
2726 
2727 		if (rt) {
2728 			/* Autoconf prefix route */
2729 			if (valid_lft == 0) {
2730 				ip6_del_rt(net, rt);
2731 				rt = NULL;
2732 			} else if (addrconf_finite_timeout(rt_expires)) {
2733 				/* not infinity */
2734 				fib6_set_expires(rt, jiffies + rt_expires);
2735 			} else {
2736 				fib6_clean_expires(rt);
2737 			}
2738 		} else if (valid_lft) {
2739 			clock_t expires = 0;
2740 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2741 			if (addrconf_finite_timeout(rt_expires)) {
2742 				/* not infinity */
2743 				flags |= RTF_EXPIRES;
2744 				expires = jiffies_to_clock_t(rt_expires);
2745 			}
2746 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2747 					      0, dev, expires, flags,
2748 					      GFP_ATOMIC);
2749 		}
2750 		fib6_info_release(rt);
2751 	}
2752 
2753 	/* Try to figure out our local address for this prefix */
2754 
2755 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
2756 		struct in6_addr addr;
2757 		bool tokenized = false, dev_addr_generated = false;
2758 
2759 		if (pinfo->prefix_len == 64) {
2760 			memcpy(&addr, &pinfo->prefix, 8);
2761 
2762 			if (!ipv6_addr_any(&in6_dev->token)) {
2763 				read_lock_bh(&in6_dev->lock);
2764 				memcpy(addr.s6_addr + 8,
2765 				       in6_dev->token.s6_addr + 8, 8);
2766 				read_unlock_bh(&in6_dev->lock);
2767 				tokenized = true;
2768 			} else if (is_addr_mode_generate_stable(in6_dev) &&
2769 				   !ipv6_generate_stable_address(&addr, 0,
2770 								 in6_dev)) {
2771 				addr_flags |= IFA_F_STABLE_PRIVACY;
2772 				goto ok;
2773 			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2774 				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2775 				goto put;
2776 			} else {
2777 				dev_addr_generated = true;
2778 			}
2779 			goto ok;
2780 		}
2781 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2782 				    pinfo->prefix_len);
2783 		goto put;
2784 
2785 ok:
2786 		err = addrconf_prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
2787 						   &addr, addr_type,
2788 						   addr_flags, sllao,
2789 						   tokenized, valid_lft,
2790 						   prefered_lft);
2791 		if (err)
2792 			goto put;
2793 
2794 		/* Ignore error case here because previous prefix add addr was
2795 		 * successful which will be notified.
2796 		 */
2797 		ndisc_ops_prefix_rcv_add_addr(net, dev, pinfo, in6_dev, &addr,
2798 					      addr_type, addr_flags, sllao,
2799 					      tokenized, valid_lft,
2800 					      prefered_lft,
2801 					      dev_addr_generated);
2802 	}
2803 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2804 put:
2805 	in6_dev_put(in6_dev);
2806 }
2807 
2808 /*
2809  *	Set destination address.
2810  *	Special case for SIT interfaces where we create a new "virtual"
2811  *	device.
2812  */
2813 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2814 {
2815 	struct in6_ifreq ireq;
2816 	struct net_device *dev;
2817 	int err = -EINVAL;
2818 
2819 	rtnl_lock();
2820 
2821 	err = -EFAULT;
2822 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2823 		goto err_exit;
2824 
2825 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2826 
2827 	err = -ENODEV;
2828 	if (!dev)
2829 		goto err_exit;
2830 
2831 #if IS_ENABLED(CONFIG_IPV6_SIT)
2832 	if (dev->type == ARPHRD_SIT) {
2833 		const struct net_device_ops *ops = dev->netdev_ops;
2834 		struct ifreq ifr;
2835 		struct ip_tunnel_parm p;
2836 
2837 		err = -EADDRNOTAVAIL;
2838 		if (!(ipv6_addr_type(&ireq.ifr6_addr) & IPV6_ADDR_COMPATv4))
2839 			goto err_exit;
2840 
2841 		memset(&p, 0, sizeof(p));
2842 		p.iph.daddr = ireq.ifr6_addr.s6_addr32[3];
2843 		p.iph.saddr = 0;
2844 		p.iph.version = 4;
2845 		p.iph.ihl = 5;
2846 		p.iph.protocol = IPPROTO_IPV6;
2847 		p.iph.ttl = 64;
2848 		ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
2849 
2850 		if (ops->ndo_do_ioctl) {
2851 			mm_segment_t oldfs = get_fs();
2852 
2853 			set_fs(KERNEL_DS);
2854 			err = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
2855 			set_fs(oldfs);
2856 		} else
2857 			err = -EOPNOTSUPP;
2858 
2859 		if (err == 0) {
2860 			err = -ENOBUFS;
2861 			dev = __dev_get_by_name(net, p.name);
2862 			if (!dev)
2863 				goto err_exit;
2864 			err = dev_open(dev, NULL);
2865 		}
2866 	}
2867 #endif
2868 
2869 err_exit:
2870 	rtnl_unlock();
2871 	return err;
2872 }
2873 
2874 static int ipv6_mc_config(struct sock *sk, bool join,
2875 			  const struct in6_addr *addr, int ifindex)
2876 {
2877 	int ret;
2878 
2879 	ASSERT_RTNL();
2880 
2881 	lock_sock(sk);
2882 	if (join)
2883 		ret = ipv6_sock_mc_join(sk, ifindex, addr);
2884 	else
2885 		ret = ipv6_sock_mc_drop(sk, ifindex, addr);
2886 	release_sock(sk);
2887 
2888 	return ret;
2889 }
2890 
2891 /*
2892  *	Manual configuration of address on an interface
2893  */
2894 static int inet6_addr_add(struct net *net, int ifindex,
2895 			  struct ifa6_config *cfg,
2896 			  struct netlink_ext_ack *extack)
2897 {
2898 	struct inet6_ifaddr *ifp;
2899 	struct inet6_dev *idev;
2900 	struct net_device *dev;
2901 	unsigned long timeout;
2902 	clock_t expires;
2903 	u32 flags;
2904 
2905 	ASSERT_RTNL();
2906 
2907 	if (cfg->plen > 128)
2908 		return -EINVAL;
2909 
2910 	/* check the lifetime */
2911 	if (!cfg->valid_lft || cfg->preferred_lft > cfg->valid_lft)
2912 		return -EINVAL;
2913 
2914 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR && cfg->plen != 64)
2915 		return -EINVAL;
2916 
2917 	dev = __dev_get_by_index(net, ifindex);
2918 	if (!dev)
2919 		return -ENODEV;
2920 
2921 	idev = addrconf_add_dev(dev);
2922 	if (IS_ERR(idev))
2923 		return PTR_ERR(idev);
2924 
2925 	if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
2926 		int ret = ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2927 					 true, cfg->pfx, ifindex);
2928 
2929 		if (ret < 0)
2930 			return ret;
2931 	}
2932 
2933 	cfg->scope = ipv6_addr_scope(cfg->pfx);
2934 
2935 	timeout = addrconf_timeout_fixup(cfg->valid_lft, HZ);
2936 	if (addrconf_finite_timeout(timeout)) {
2937 		expires = jiffies_to_clock_t(timeout * HZ);
2938 		cfg->valid_lft = timeout;
2939 		flags = RTF_EXPIRES;
2940 	} else {
2941 		expires = 0;
2942 		flags = 0;
2943 		cfg->ifa_flags |= IFA_F_PERMANENT;
2944 	}
2945 
2946 	timeout = addrconf_timeout_fixup(cfg->preferred_lft, HZ);
2947 	if (addrconf_finite_timeout(timeout)) {
2948 		if (timeout == 0)
2949 			cfg->ifa_flags |= IFA_F_DEPRECATED;
2950 		cfg->preferred_lft = timeout;
2951 	}
2952 
2953 	ifp = ipv6_add_addr(idev, cfg, true, extack);
2954 	if (!IS_ERR(ifp)) {
2955 		if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
2956 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
2957 					      ifp->rt_priority, dev, expires,
2958 					      flags, GFP_KERNEL);
2959 		}
2960 
2961 		/* Send a netlink notification if DAD is enabled and
2962 		 * optimistic flag is not set
2963 		 */
2964 		if (!(ifp->flags & (IFA_F_OPTIMISTIC | IFA_F_NODAD)))
2965 			ipv6_ifa_notify(0, ifp);
2966 		/*
2967 		 * Note that section 3.1 of RFC 4429 indicates
2968 		 * that the Optimistic flag should not be set for
2969 		 * manually configured addresses
2970 		 */
2971 		addrconf_dad_start(ifp);
2972 		if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR)
2973 			manage_tempaddrs(idev, ifp, cfg->valid_lft,
2974 					 cfg->preferred_lft, true, jiffies);
2975 		in6_ifa_put(ifp);
2976 		addrconf_verify_rtnl();
2977 		return 0;
2978 	} else if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
2979 		ipv6_mc_config(net->ipv6.mc_autojoin_sk, false,
2980 			       cfg->pfx, ifindex);
2981 	}
2982 
2983 	return PTR_ERR(ifp);
2984 }
2985 
2986 static int inet6_addr_del(struct net *net, int ifindex, u32 ifa_flags,
2987 			  const struct in6_addr *pfx, unsigned int plen)
2988 {
2989 	struct inet6_ifaddr *ifp;
2990 	struct inet6_dev *idev;
2991 	struct net_device *dev;
2992 
2993 	if (plen > 128)
2994 		return -EINVAL;
2995 
2996 	dev = __dev_get_by_index(net, ifindex);
2997 	if (!dev)
2998 		return -ENODEV;
2999 
3000 	idev = __in6_dev_get(dev);
3001 	if (!idev)
3002 		return -ENXIO;
3003 
3004 	read_lock_bh(&idev->lock);
3005 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
3006 		if (ifp->prefix_len == plen &&
3007 		    ipv6_addr_equal(pfx, &ifp->addr)) {
3008 			in6_ifa_hold(ifp);
3009 			read_unlock_bh(&idev->lock);
3010 
3011 			if (!(ifp->flags & IFA_F_TEMPORARY) &&
3012 			    (ifa_flags & IFA_F_MANAGETEMPADDR))
3013 				manage_tempaddrs(idev, ifp, 0, 0, false,
3014 						 jiffies);
3015 			ipv6_del_addr(ifp);
3016 			addrconf_verify_rtnl();
3017 			if (ipv6_addr_is_multicast(pfx)) {
3018 				ipv6_mc_config(net->ipv6.mc_autojoin_sk,
3019 					       false, pfx, dev->ifindex);
3020 			}
3021 			return 0;
3022 		}
3023 	}
3024 	read_unlock_bh(&idev->lock);
3025 	return -EADDRNOTAVAIL;
3026 }
3027 
3028 
3029 int addrconf_add_ifaddr(struct net *net, void __user *arg)
3030 {
3031 	struct ifa6_config cfg = {
3032 		.ifa_flags = IFA_F_PERMANENT,
3033 		.preferred_lft = INFINITY_LIFE_TIME,
3034 		.valid_lft = INFINITY_LIFE_TIME,
3035 	};
3036 	struct in6_ifreq ireq;
3037 	int err;
3038 
3039 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3040 		return -EPERM;
3041 
3042 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3043 		return -EFAULT;
3044 
3045 	cfg.pfx = &ireq.ifr6_addr;
3046 	cfg.plen = ireq.ifr6_prefixlen;
3047 
3048 	rtnl_lock();
3049 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &cfg, NULL);
3050 	rtnl_unlock();
3051 	return err;
3052 }
3053 
3054 int addrconf_del_ifaddr(struct net *net, void __user *arg)
3055 {
3056 	struct in6_ifreq ireq;
3057 	int err;
3058 
3059 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3060 		return -EPERM;
3061 
3062 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3063 		return -EFAULT;
3064 
3065 	rtnl_lock();
3066 	err = inet6_addr_del(net, ireq.ifr6_ifindex, 0, &ireq.ifr6_addr,
3067 			     ireq.ifr6_prefixlen);
3068 	rtnl_unlock();
3069 	return err;
3070 }
3071 
3072 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
3073 		     int plen, int scope)
3074 {
3075 	struct inet6_ifaddr *ifp;
3076 	struct ifa6_config cfg = {
3077 		.pfx = addr,
3078 		.plen = plen,
3079 		.ifa_flags = IFA_F_PERMANENT,
3080 		.valid_lft = INFINITY_LIFE_TIME,
3081 		.preferred_lft = INFINITY_LIFE_TIME,
3082 		.scope = scope
3083 	};
3084 
3085 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3086 	if (!IS_ERR(ifp)) {
3087 		spin_lock_bh(&ifp->lock);
3088 		ifp->flags &= ~IFA_F_TENTATIVE;
3089 		spin_unlock_bh(&ifp->lock);
3090 		rt_genid_bump_ipv6(dev_net(idev->dev));
3091 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3092 		in6_ifa_put(ifp);
3093 	}
3094 }
3095 
3096 #if IS_ENABLED(CONFIG_IPV6_SIT)
3097 static void sit_add_v4_addrs(struct inet6_dev *idev)
3098 {
3099 	struct in6_addr addr;
3100 	struct net_device *dev;
3101 	struct net *net = dev_net(idev->dev);
3102 	int scope, plen;
3103 	u32 pflags = 0;
3104 
3105 	ASSERT_RTNL();
3106 
3107 	memset(&addr, 0, sizeof(struct in6_addr));
3108 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
3109 
3110 	if (idev->dev->flags&IFF_POINTOPOINT) {
3111 		addr.s6_addr32[0] = htonl(0xfe800000);
3112 		scope = IFA_LINK;
3113 		plen = 64;
3114 	} else {
3115 		scope = IPV6_ADDR_COMPATv4;
3116 		plen = 96;
3117 		pflags |= RTF_NONEXTHOP;
3118 	}
3119 
3120 	if (addr.s6_addr32[3]) {
3121 		add_addr(idev, &addr, plen, scope);
3122 		addrconf_prefix_route(&addr, plen, 0, idev->dev, 0, pflags,
3123 				      GFP_KERNEL);
3124 		return;
3125 	}
3126 
3127 	for_each_netdev(net, dev) {
3128 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
3129 		if (in_dev && (dev->flags & IFF_UP)) {
3130 			struct in_ifaddr *ifa;
3131 			int flag = scope;
3132 
3133 			in_dev_for_each_ifa_rtnl(ifa, in_dev) {
3134 				addr.s6_addr32[3] = ifa->ifa_local;
3135 
3136 				if (ifa->ifa_scope == RT_SCOPE_LINK)
3137 					continue;
3138 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
3139 					if (idev->dev->flags&IFF_POINTOPOINT)
3140 						continue;
3141 					flag |= IFA_HOST;
3142 				}
3143 
3144 				add_addr(idev, &addr, plen, flag);
3145 				addrconf_prefix_route(&addr, plen, 0, idev->dev,
3146 						      0, pflags, GFP_KERNEL);
3147 			}
3148 		}
3149 	}
3150 }
3151 #endif
3152 
3153 static void init_loopback(struct net_device *dev)
3154 {
3155 	struct inet6_dev  *idev;
3156 
3157 	/* ::1 */
3158 
3159 	ASSERT_RTNL();
3160 
3161 	idev = ipv6_find_idev(dev);
3162 	if (IS_ERR(idev)) {
3163 		pr_debug("%s: add_dev failed\n", __func__);
3164 		return;
3165 	}
3166 
3167 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST);
3168 }
3169 
3170 void addrconf_add_linklocal(struct inet6_dev *idev,
3171 			    const struct in6_addr *addr, u32 flags)
3172 {
3173 	struct ifa6_config cfg = {
3174 		.pfx = addr,
3175 		.plen = 64,
3176 		.ifa_flags = flags | IFA_F_PERMANENT,
3177 		.valid_lft = INFINITY_LIFE_TIME,
3178 		.preferred_lft = INFINITY_LIFE_TIME,
3179 		.scope = IFA_LINK
3180 	};
3181 	struct inet6_ifaddr *ifp;
3182 
3183 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
3184 	if ((dev_net(idev->dev)->ipv6.devconf_all->optimistic_dad ||
3185 	     idev->cnf.optimistic_dad) &&
3186 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
3187 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
3188 #endif
3189 
3190 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3191 	if (!IS_ERR(ifp)) {
3192 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, 0, idev->dev,
3193 				      0, 0, GFP_ATOMIC);
3194 		addrconf_dad_start(ifp);
3195 		in6_ifa_put(ifp);
3196 	}
3197 }
3198 EXPORT_SYMBOL_GPL(addrconf_add_linklocal);
3199 
3200 static bool ipv6_reserved_interfaceid(struct in6_addr address)
3201 {
3202 	if ((address.s6_addr32[2] | address.s6_addr32[3]) == 0)
3203 		return true;
3204 
3205 	if (address.s6_addr32[2] == htonl(0x02005eff) &&
3206 	    ((address.s6_addr32[3] & htonl(0xfe000000)) == htonl(0xfe000000)))
3207 		return true;
3208 
3209 	if (address.s6_addr32[2] == htonl(0xfdffffff) &&
3210 	    ((address.s6_addr32[3] & htonl(0xffffff80)) == htonl(0xffffff80)))
3211 		return true;
3212 
3213 	return false;
3214 }
3215 
3216 static int ipv6_generate_stable_address(struct in6_addr *address,
3217 					u8 dad_count,
3218 					const struct inet6_dev *idev)
3219 {
3220 	static DEFINE_SPINLOCK(lock);
3221 	static __u32 digest[SHA_DIGEST_WORDS];
3222 	static __u32 workspace[SHA_WORKSPACE_WORDS];
3223 
3224 	static union {
3225 		char __data[SHA_MESSAGE_BYTES];
3226 		struct {
3227 			struct in6_addr secret;
3228 			__be32 prefix[2];
3229 			unsigned char hwaddr[MAX_ADDR_LEN];
3230 			u8 dad_count;
3231 		} __packed;
3232 	} data;
3233 
3234 	struct in6_addr secret;
3235 	struct in6_addr temp;
3236 	struct net *net = dev_net(idev->dev);
3237 
3238 	BUILD_BUG_ON(sizeof(data.__data) != sizeof(data));
3239 
3240 	if (idev->cnf.stable_secret.initialized)
3241 		secret = idev->cnf.stable_secret.secret;
3242 	else if (net->ipv6.devconf_dflt->stable_secret.initialized)
3243 		secret = net->ipv6.devconf_dflt->stable_secret.secret;
3244 	else
3245 		return -1;
3246 
3247 retry:
3248 	spin_lock_bh(&lock);
3249 
3250 	sha_init(digest);
3251 	memset(&data, 0, sizeof(data));
3252 	memset(workspace, 0, sizeof(workspace));
3253 	memcpy(data.hwaddr, idev->dev->perm_addr, idev->dev->addr_len);
3254 	data.prefix[0] = address->s6_addr32[0];
3255 	data.prefix[1] = address->s6_addr32[1];
3256 	data.secret = secret;
3257 	data.dad_count = dad_count;
3258 
3259 	sha_transform(digest, data.__data, workspace);
3260 
3261 	temp = *address;
3262 	temp.s6_addr32[2] = (__force __be32)digest[0];
3263 	temp.s6_addr32[3] = (__force __be32)digest[1];
3264 
3265 	spin_unlock_bh(&lock);
3266 
3267 	if (ipv6_reserved_interfaceid(temp)) {
3268 		dad_count++;
3269 		if (dad_count > dev_net(idev->dev)->ipv6.sysctl.idgen_retries)
3270 			return -1;
3271 		goto retry;
3272 	}
3273 
3274 	*address = temp;
3275 	return 0;
3276 }
3277 
3278 static void ipv6_gen_mode_random_init(struct inet6_dev *idev)
3279 {
3280 	struct ipv6_stable_secret *s = &idev->cnf.stable_secret;
3281 
3282 	if (s->initialized)
3283 		return;
3284 	s = &idev->cnf.stable_secret;
3285 	get_random_bytes(&s->secret, sizeof(s->secret));
3286 	s->initialized = true;
3287 }
3288 
3289 static void addrconf_addr_gen(struct inet6_dev *idev, bool prefix_route)
3290 {
3291 	struct in6_addr addr;
3292 
3293 	/* no link local addresses on L3 master devices */
3294 	if (netif_is_l3_master(idev->dev))
3295 		return;
3296 
3297 	ipv6_addr_set(&addr, htonl(0xFE800000), 0, 0, 0);
3298 
3299 	switch (idev->cnf.addr_gen_mode) {
3300 	case IN6_ADDR_GEN_MODE_RANDOM:
3301 		ipv6_gen_mode_random_init(idev);
3302 		/* fallthrough */
3303 	case IN6_ADDR_GEN_MODE_STABLE_PRIVACY:
3304 		if (!ipv6_generate_stable_address(&addr, 0, idev))
3305 			addrconf_add_linklocal(idev, &addr,
3306 					       IFA_F_STABLE_PRIVACY);
3307 		else if (prefix_route)
3308 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3309 					      0, 0, GFP_KERNEL);
3310 		break;
3311 	case IN6_ADDR_GEN_MODE_EUI64:
3312 		/* addrconf_add_linklocal also adds a prefix_route and we
3313 		 * only need to care about prefix routes if ipv6_generate_eui64
3314 		 * couldn't generate one.
3315 		 */
3316 		if (ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) == 0)
3317 			addrconf_add_linklocal(idev, &addr, 0);
3318 		else if (prefix_route)
3319 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3320 					      0, 0, GFP_KERNEL);
3321 		break;
3322 	case IN6_ADDR_GEN_MODE_NONE:
3323 	default:
3324 		/* will not add any link local address */
3325 		break;
3326 	}
3327 }
3328 
3329 static void addrconf_dev_config(struct net_device *dev)
3330 {
3331 	struct inet6_dev *idev;
3332 
3333 	ASSERT_RTNL();
3334 
3335 	if ((dev->type != ARPHRD_ETHER) &&
3336 	    (dev->type != ARPHRD_FDDI) &&
3337 	    (dev->type != ARPHRD_ARCNET) &&
3338 	    (dev->type != ARPHRD_INFINIBAND) &&
3339 	    (dev->type != ARPHRD_IEEE1394) &&
3340 	    (dev->type != ARPHRD_TUNNEL6) &&
3341 	    (dev->type != ARPHRD_6LOWPAN) &&
3342 	    (dev->type != ARPHRD_IP6GRE) &&
3343 	    (dev->type != ARPHRD_IPGRE) &&
3344 	    (dev->type != ARPHRD_TUNNEL) &&
3345 	    (dev->type != ARPHRD_NONE) &&
3346 	    (dev->type != ARPHRD_RAWIP)) {
3347 		/* Alas, we support only Ethernet autoconfiguration. */
3348 		return;
3349 	}
3350 
3351 	idev = addrconf_add_dev(dev);
3352 	if (IS_ERR(idev))
3353 		return;
3354 
3355 	/* this device type has no EUI support */
3356 	if (dev->type == ARPHRD_NONE &&
3357 	    idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64)
3358 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_RANDOM;
3359 
3360 	addrconf_addr_gen(idev, false);
3361 }
3362 
3363 #if IS_ENABLED(CONFIG_IPV6_SIT)
3364 static void addrconf_sit_config(struct net_device *dev)
3365 {
3366 	struct inet6_dev *idev;
3367 
3368 	ASSERT_RTNL();
3369 
3370 	/*
3371 	 * Configure the tunnel with one of our IPv4
3372 	 * addresses... we should configure all of
3373 	 * our v4 addrs in the tunnel
3374 	 */
3375 
3376 	idev = ipv6_find_idev(dev);
3377 	if (IS_ERR(idev)) {
3378 		pr_debug("%s: add_dev failed\n", __func__);
3379 		return;
3380 	}
3381 
3382 	if (dev->priv_flags & IFF_ISATAP) {
3383 		addrconf_addr_gen(idev, false);
3384 		return;
3385 	}
3386 
3387 	sit_add_v4_addrs(idev);
3388 
3389 	if (dev->flags&IFF_POINTOPOINT)
3390 		addrconf_add_mroute(dev);
3391 }
3392 #endif
3393 
3394 #if IS_ENABLED(CONFIG_NET_IPGRE)
3395 static void addrconf_gre_config(struct net_device *dev)
3396 {
3397 	struct inet6_dev *idev;
3398 
3399 	ASSERT_RTNL();
3400 
3401 	idev = ipv6_find_idev(dev);
3402 	if (IS_ERR(idev)) {
3403 		pr_debug("%s: add_dev failed\n", __func__);
3404 		return;
3405 	}
3406 
3407 	addrconf_addr_gen(idev, true);
3408 	if (dev->flags & IFF_POINTOPOINT)
3409 		addrconf_add_mroute(dev);
3410 }
3411 #endif
3412 
3413 static int fixup_permanent_addr(struct net *net,
3414 				struct inet6_dev *idev,
3415 				struct inet6_ifaddr *ifp)
3416 {
3417 	/* !fib6_node means the host route was removed from the
3418 	 * FIB, for example, if 'lo' device is taken down. In that
3419 	 * case regenerate the host route.
3420 	 */
3421 	if (!ifp->rt || !ifp->rt->fib6_node) {
3422 		struct fib6_info *f6i, *prev;
3423 
3424 		f6i = addrconf_f6i_alloc(net, idev, &ifp->addr, false,
3425 					 GFP_ATOMIC);
3426 		if (IS_ERR(f6i))
3427 			return PTR_ERR(f6i);
3428 
3429 		/* ifp->rt can be accessed outside of rtnl */
3430 		spin_lock(&ifp->lock);
3431 		prev = ifp->rt;
3432 		ifp->rt = f6i;
3433 		spin_unlock(&ifp->lock);
3434 
3435 		fib6_info_release(prev);
3436 	}
3437 
3438 	if (!(ifp->flags & IFA_F_NOPREFIXROUTE)) {
3439 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3440 				      ifp->rt_priority, idev->dev, 0, 0,
3441 				      GFP_ATOMIC);
3442 	}
3443 
3444 	if (ifp->state == INET6_IFADDR_STATE_PREDAD)
3445 		addrconf_dad_start(ifp);
3446 
3447 	return 0;
3448 }
3449 
3450 static void addrconf_permanent_addr(struct net *net, struct net_device *dev)
3451 {
3452 	struct inet6_ifaddr *ifp, *tmp;
3453 	struct inet6_dev *idev;
3454 
3455 	idev = __in6_dev_get(dev);
3456 	if (!idev)
3457 		return;
3458 
3459 	write_lock_bh(&idev->lock);
3460 
3461 	list_for_each_entry_safe(ifp, tmp, &idev->addr_list, if_list) {
3462 		if ((ifp->flags & IFA_F_PERMANENT) &&
3463 		    fixup_permanent_addr(net, idev, ifp) < 0) {
3464 			write_unlock_bh(&idev->lock);
3465 			in6_ifa_hold(ifp);
3466 			ipv6_del_addr(ifp);
3467 			write_lock_bh(&idev->lock);
3468 
3469 			net_info_ratelimited("%s: Failed to add prefix route for address %pI6c; dropping\n",
3470 					     idev->dev->name, &ifp->addr);
3471 		}
3472 	}
3473 
3474 	write_unlock_bh(&idev->lock);
3475 }
3476 
3477 static int addrconf_notify(struct notifier_block *this, unsigned long event,
3478 			   void *ptr)
3479 {
3480 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3481 	struct netdev_notifier_change_info *change_info;
3482 	struct netdev_notifier_changeupper_info *info;
3483 	struct inet6_dev *idev = __in6_dev_get(dev);
3484 	struct net *net = dev_net(dev);
3485 	int run_pending = 0;
3486 	int err;
3487 
3488 	switch (event) {
3489 	case NETDEV_REGISTER:
3490 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
3491 			idev = ipv6_add_dev(dev);
3492 			if (IS_ERR(idev))
3493 				return notifier_from_errno(PTR_ERR(idev));
3494 		}
3495 		break;
3496 
3497 	case NETDEV_CHANGEMTU:
3498 		/* if MTU under IPV6_MIN_MTU stop IPv6 on this interface. */
3499 		if (dev->mtu < IPV6_MIN_MTU) {
3500 			addrconf_ifdown(dev, dev != net->loopback_dev);
3501 			break;
3502 		}
3503 
3504 		if (idev) {
3505 			rt6_mtu_change(dev, dev->mtu);
3506 			idev->cnf.mtu6 = dev->mtu;
3507 			break;
3508 		}
3509 
3510 		/* allocate new idev */
3511 		idev = ipv6_add_dev(dev);
3512 		if (IS_ERR(idev))
3513 			break;
3514 
3515 		/* device is still not ready */
3516 		if (!(idev->if_flags & IF_READY))
3517 			break;
3518 
3519 		run_pending = 1;
3520 
3521 		/* fall through */
3522 
3523 	case NETDEV_UP:
3524 	case NETDEV_CHANGE:
3525 		if (dev->flags & IFF_SLAVE)
3526 			break;
3527 
3528 		if (idev && idev->cnf.disable_ipv6)
3529 			break;
3530 
3531 		if (event == NETDEV_UP) {
3532 			/* restore routes for permanent addresses */
3533 			addrconf_permanent_addr(net, dev);
3534 
3535 			if (!addrconf_link_ready(dev)) {
3536 				/* device is not ready yet. */
3537 				pr_debug("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
3538 					 dev->name);
3539 				break;
3540 			}
3541 
3542 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
3543 				idev = ipv6_add_dev(dev);
3544 
3545 			if (!IS_ERR_OR_NULL(idev)) {
3546 				idev->if_flags |= IF_READY;
3547 				run_pending = 1;
3548 			}
3549 		} else if (event == NETDEV_CHANGE) {
3550 			if (!addrconf_link_ready(dev)) {
3551 				/* device is still not ready. */
3552 				rt6_sync_down_dev(dev, event);
3553 				break;
3554 			}
3555 
3556 			if (!IS_ERR_OR_NULL(idev)) {
3557 				if (idev->if_flags & IF_READY) {
3558 					/* device is already configured -
3559 					 * but resend MLD reports, we might
3560 					 * have roamed and need to update
3561 					 * multicast snooping switches
3562 					 */
3563 					ipv6_mc_up(idev);
3564 					change_info = ptr;
3565 					if (change_info->flags_changed & IFF_NOARP)
3566 						addrconf_dad_run(idev, true);
3567 					rt6_sync_up(dev, RTNH_F_LINKDOWN);
3568 					break;
3569 				}
3570 				idev->if_flags |= IF_READY;
3571 			}
3572 
3573 			pr_info("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
3574 				dev->name);
3575 
3576 			run_pending = 1;
3577 		}
3578 
3579 		switch (dev->type) {
3580 #if IS_ENABLED(CONFIG_IPV6_SIT)
3581 		case ARPHRD_SIT:
3582 			addrconf_sit_config(dev);
3583 			break;
3584 #endif
3585 #if IS_ENABLED(CONFIG_NET_IPGRE)
3586 		case ARPHRD_IPGRE:
3587 			addrconf_gre_config(dev);
3588 			break;
3589 #endif
3590 		case ARPHRD_LOOPBACK:
3591 			init_loopback(dev);
3592 			break;
3593 
3594 		default:
3595 			addrconf_dev_config(dev);
3596 			break;
3597 		}
3598 
3599 		if (!IS_ERR_OR_NULL(idev)) {
3600 			if (run_pending)
3601 				addrconf_dad_run(idev, false);
3602 
3603 			/* Device has an address by now */
3604 			rt6_sync_up(dev, RTNH_F_DEAD);
3605 
3606 			/*
3607 			 * If the MTU changed during the interface down,
3608 			 * when the interface up, the changed MTU must be
3609 			 * reflected in the idev as well as routers.
3610 			 */
3611 			if (idev->cnf.mtu6 != dev->mtu &&
3612 			    dev->mtu >= IPV6_MIN_MTU) {
3613 				rt6_mtu_change(dev, dev->mtu);
3614 				idev->cnf.mtu6 = dev->mtu;
3615 			}
3616 			idev->tstamp = jiffies;
3617 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
3618 
3619 			/*
3620 			 * If the changed mtu during down is lower than
3621 			 * IPV6_MIN_MTU stop IPv6 on this interface.
3622 			 */
3623 			if (dev->mtu < IPV6_MIN_MTU)
3624 				addrconf_ifdown(dev, dev != net->loopback_dev);
3625 		}
3626 		break;
3627 
3628 	case NETDEV_DOWN:
3629 	case NETDEV_UNREGISTER:
3630 		/*
3631 		 *	Remove all addresses from this interface.
3632 		 */
3633 		addrconf_ifdown(dev, event != NETDEV_DOWN);
3634 		break;
3635 
3636 	case NETDEV_CHANGENAME:
3637 		if (idev) {
3638 			snmp6_unregister_dev(idev);
3639 			addrconf_sysctl_unregister(idev);
3640 			err = addrconf_sysctl_register(idev);
3641 			if (err)
3642 				return notifier_from_errno(err);
3643 			err = snmp6_register_dev(idev);
3644 			if (err) {
3645 				addrconf_sysctl_unregister(idev);
3646 				return notifier_from_errno(err);
3647 			}
3648 		}
3649 		break;
3650 
3651 	case NETDEV_PRE_TYPE_CHANGE:
3652 	case NETDEV_POST_TYPE_CHANGE:
3653 		if (idev)
3654 			addrconf_type_change(dev, event);
3655 		break;
3656 
3657 	case NETDEV_CHANGEUPPER:
3658 		info = ptr;
3659 
3660 		/* flush all routes if dev is linked to or unlinked from
3661 		 * an L3 master device (e.g., VRF)
3662 		 */
3663 		if (info->upper_dev && netif_is_l3_master(info->upper_dev))
3664 			addrconf_ifdown(dev, 0);
3665 	}
3666 
3667 	return NOTIFY_OK;
3668 }
3669 
3670 /*
3671  *	addrconf module should be notified of a device going up
3672  */
3673 static struct notifier_block ipv6_dev_notf = {
3674 	.notifier_call = addrconf_notify,
3675 	.priority = ADDRCONF_NOTIFY_PRIORITY,
3676 };
3677 
3678 static void addrconf_type_change(struct net_device *dev, unsigned long event)
3679 {
3680 	struct inet6_dev *idev;
3681 	ASSERT_RTNL();
3682 
3683 	idev = __in6_dev_get(dev);
3684 
3685 	if (event == NETDEV_POST_TYPE_CHANGE)
3686 		ipv6_mc_remap(idev);
3687 	else if (event == NETDEV_PRE_TYPE_CHANGE)
3688 		ipv6_mc_unmap(idev);
3689 }
3690 
3691 static bool addr_is_local(const struct in6_addr *addr)
3692 {
3693 	return ipv6_addr_type(addr) &
3694 		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
3695 }
3696 
3697 static int addrconf_ifdown(struct net_device *dev, int how)
3698 {
3699 	unsigned long event = how ? NETDEV_UNREGISTER : NETDEV_DOWN;
3700 	struct net *net = dev_net(dev);
3701 	struct inet6_dev *idev;
3702 	struct inet6_ifaddr *ifa, *tmp;
3703 	bool keep_addr = false;
3704 	int state, i;
3705 
3706 	ASSERT_RTNL();
3707 
3708 	rt6_disable_ip(dev, event);
3709 
3710 	idev = __in6_dev_get(dev);
3711 	if (!idev)
3712 		return -ENODEV;
3713 
3714 	/*
3715 	 * Step 1: remove reference to ipv6 device from parent device.
3716 	 *	   Do not dev_put!
3717 	 */
3718 	if (how) {
3719 		idev->dead = 1;
3720 
3721 		/* protected by rtnl_lock */
3722 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
3723 
3724 		/* Step 1.5: remove snmp6 entry */
3725 		snmp6_unregister_dev(idev);
3726 
3727 	}
3728 
3729 	/* combine the user config with event to determine if permanent
3730 	 * addresses are to be removed from address hash table
3731 	 */
3732 	if (!how && !idev->cnf.disable_ipv6) {
3733 		/* aggregate the system setting and interface setting */
3734 		int _keep_addr = net->ipv6.devconf_all->keep_addr_on_down;
3735 
3736 		if (!_keep_addr)
3737 			_keep_addr = idev->cnf.keep_addr_on_down;
3738 
3739 		keep_addr = (_keep_addr > 0);
3740 	}
3741 
3742 	/* Step 2: clear hash table */
3743 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3744 		struct hlist_head *h = &inet6_addr_lst[i];
3745 
3746 		spin_lock_bh(&addrconf_hash_lock);
3747 restart:
3748 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
3749 			if (ifa->idev == idev) {
3750 				addrconf_del_dad_work(ifa);
3751 				/* combined flag + permanent flag decide if
3752 				 * address is retained on a down event
3753 				 */
3754 				if (!keep_addr ||
3755 				    !(ifa->flags & IFA_F_PERMANENT) ||
3756 				    addr_is_local(&ifa->addr)) {
3757 					hlist_del_init_rcu(&ifa->addr_lst);
3758 					goto restart;
3759 				}
3760 			}
3761 		}
3762 		spin_unlock_bh(&addrconf_hash_lock);
3763 	}
3764 
3765 	write_lock_bh(&idev->lock);
3766 
3767 	addrconf_del_rs_timer(idev);
3768 
3769 	/* Step 2: clear flags for stateless addrconf */
3770 	if (!how)
3771 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3772 
3773 	/* Step 3: clear tempaddr list */
3774 	while (!list_empty(&idev->tempaddr_list)) {
3775 		ifa = list_first_entry(&idev->tempaddr_list,
3776 				       struct inet6_ifaddr, tmp_list);
3777 		list_del(&ifa->tmp_list);
3778 		write_unlock_bh(&idev->lock);
3779 		spin_lock_bh(&ifa->lock);
3780 
3781 		if (ifa->ifpub) {
3782 			in6_ifa_put(ifa->ifpub);
3783 			ifa->ifpub = NULL;
3784 		}
3785 		spin_unlock_bh(&ifa->lock);
3786 		in6_ifa_put(ifa);
3787 		write_lock_bh(&idev->lock);
3788 	}
3789 
3790 	list_for_each_entry_safe(ifa, tmp, &idev->addr_list, if_list) {
3791 		struct fib6_info *rt = NULL;
3792 		bool keep;
3793 
3794 		addrconf_del_dad_work(ifa);
3795 
3796 		keep = keep_addr && (ifa->flags & IFA_F_PERMANENT) &&
3797 			!addr_is_local(&ifa->addr);
3798 
3799 		write_unlock_bh(&idev->lock);
3800 		spin_lock_bh(&ifa->lock);
3801 
3802 		if (keep) {
3803 			/* set state to skip the notifier below */
3804 			state = INET6_IFADDR_STATE_DEAD;
3805 			ifa->state = INET6_IFADDR_STATE_PREDAD;
3806 			if (!(ifa->flags & IFA_F_NODAD))
3807 				ifa->flags |= IFA_F_TENTATIVE;
3808 
3809 			rt = ifa->rt;
3810 			ifa->rt = NULL;
3811 		} else {
3812 			state = ifa->state;
3813 			ifa->state = INET6_IFADDR_STATE_DEAD;
3814 		}
3815 
3816 		spin_unlock_bh(&ifa->lock);
3817 
3818 		if (rt)
3819 			ip6_del_rt(net, rt);
3820 
3821 		if (state != INET6_IFADDR_STATE_DEAD) {
3822 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
3823 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
3824 		} else {
3825 			if (idev->cnf.forwarding)
3826 				addrconf_leave_anycast(ifa);
3827 			addrconf_leave_solict(ifa->idev, &ifa->addr);
3828 		}
3829 
3830 		write_lock_bh(&idev->lock);
3831 		if (!keep) {
3832 			list_del_rcu(&ifa->if_list);
3833 			in6_ifa_put(ifa);
3834 		}
3835 	}
3836 
3837 	write_unlock_bh(&idev->lock);
3838 
3839 	/* Step 5: Discard anycast and multicast list */
3840 	if (how) {
3841 		ipv6_ac_destroy_dev(idev);
3842 		ipv6_mc_destroy_dev(idev);
3843 	} else {
3844 		ipv6_mc_down(idev);
3845 	}
3846 
3847 	idev->tstamp = jiffies;
3848 
3849 	/* Last: Shot the device (if unregistered) */
3850 	if (how) {
3851 		addrconf_sysctl_unregister(idev);
3852 		neigh_parms_release(&nd_tbl, idev->nd_parms);
3853 		neigh_ifdown(&nd_tbl, dev);
3854 		in6_dev_put(idev);
3855 	}
3856 	return 0;
3857 }
3858 
3859 static void addrconf_rs_timer(struct timer_list *t)
3860 {
3861 	struct inet6_dev *idev = from_timer(idev, t, rs_timer);
3862 	struct net_device *dev = idev->dev;
3863 	struct in6_addr lladdr;
3864 
3865 	write_lock(&idev->lock);
3866 	if (idev->dead || !(idev->if_flags & IF_READY))
3867 		goto out;
3868 
3869 	if (!ipv6_accept_ra(idev))
3870 		goto out;
3871 
3872 	/* Announcement received after solicitation was sent */
3873 	if (idev->if_flags & IF_RA_RCVD)
3874 		goto out;
3875 
3876 	if (idev->rs_probes++ < idev->cnf.rtr_solicits || idev->cnf.rtr_solicits < 0) {
3877 		write_unlock(&idev->lock);
3878 		if (!ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
3879 			ndisc_send_rs(dev, &lladdr,
3880 				      &in6addr_linklocal_allrouters);
3881 		else
3882 			goto put;
3883 
3884 		write_lock(&idev->lock);
3885 		idev->rs_interval = rfc3315_s14_backoff_update(
3886 			idev->rs_interval, idev->cnf.rtr_solicit_max_interval);
3887 		/* The wait after the last probe can be shorter */
3888 		addrconf_mod_rs_timer(idev, (idev->rs_probes ==
3889 					     idev->cnf.rtr_solicits) ?
3890 				      idev->cnf.rtr_solicit_delay :
3891 				      idev->rs_interval);
3892 	} else {
3893 		/*
3894 		 * Note: we do not support deprecated "all on-link"
3895 		 * assumption any longer.
3896 		 */
3897 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
3898 	}
3899 
3900 out:
3901 	write_unlock(&idev->lock);
3902 put:
3903 	in6_dev_put(idev);
3904 }
3905 
3906 /*
3907  *	Duplicate Address Detection
3908  */
3909 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
3910 {
3911 	unsigned long rand_num;
3912 	struct inet6_dev *idev = ifp->idev;
3913 	u64 nonce;
3914 
3915 	if (ifp->flags & IFA_F_OPTIMISTIC)
3916 		rand_num = 0;
3917 	else
3918 		rand_num = prandom_u32() % (idev->cnf.rtr_solicit_delay ? : 1);
3919 
3920 	nonce = 0;
3921 	if (idev->cnf.enhanced_dad ||
3922 	    dev_net(idev->dev)->ipv6.devconf_all->enhanced_dad) {
3923 		do
3924 			get_random_bytes(&nonce, 6);
3925 		while (nonce == 0);
3926 	}
3927 	ifp->dad_nonce = nonce;
3928 	ifp->dad_probes = idev->cnf.dad_transmits;
3929 	addrconf_mod_dad_work(ifp, rand_num);
3930 }
3931 
3932 static void addrconf_dad_begin(struct inet6_ifaddr *ifp)
3933 {
3934 	struct inet6_dev *idev = ifp->idev;
3935 	struct net_device *dev = idev->dev;
3936 	bool bump_id, notify = false;
3937 	struct net *net;
3938 
3939 	addrconf_join_solict(dev, &ifp->addr);
3940 
3941 	prandom_seed((__force u32) ifp->addr.s6_addr32[3]);
3942 
3943 	read_lock_bh(&idev->lock);
3944 	spin_lock(&ifp->lock);
3945 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
3946 		goto out;
3947 
3948 	net = dev_net(dev);
3949 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
3950 	    (net->ipv6.devconf_all->accept_dad < 1 &&
3951 	     idev->cnf.accept_dad < 1) ||
3952 	    !(ifp->flags&IFA_F_TENTATIVE) ||
3953 	    ifp->flags & IFA_F_NODAD) {
3954 		bool send_na = false;
3955 
3956 		if (ifp->flags & IFA_F_TENTATIVE &&
3957 		    !(ifp->flags & IFA_F_OPTIMISTIC))
3958 			send_na = true;
3959 		bump_id = ifp->flags & IFA_F_TENTATIVE;
3960 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3961 		spin_unlock(&ifp->lock);
3962 		read_unlock_bh(&idev->lock);
3963 
3964 		addrconf_dad_completed(ifp, bump_id, send_na);
3965 		return;
3966 	}
3967 
3968 	if (!(idev->if_flags & IF_READY)) {
3969 		spin_unlock(&ifp->lock);
3970 		read_unlock_bh(&idev->lock);
3971 		/*
3972 		 * If the device is not ready:
3973 		 * - keep it tentative if it is a permanent address.
3974 		 * - otherwise, kill it.
3975 		 */
3976 		in6_ifa_hold(ifp);
3977 		addrconf_dad_stop(ifp, 0);
3978 		return;
3979 	}
3980 
3981 	/*
3982 	 * Optimistic nodes can start receiving
3983 	 * Frames right away
3984 	 */
3985 	if (ifp->flags & IFA_F_OPTIMISTIC) {
3986 		ip6_ins_rt(net, ifp->rt);
3987 		if (ipv6_use_optimistic_addr(net, idev)) {
3988 			/* Because optimistic nodes can use this address,
3989 			 * notify listeners. If DAD fails, RTM_DELADDR is sent.
3990 			 */
3991 			notify = true;
3992 		}
3993 	}
3994 
3995 	addrconf_dad_kick(ifp);
3996 out:
3997 	spin_unlock(&ifp->lock);
3998 	read_unlock_bh(&idev->lock);
3999 	if (notify)
4000 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
4001 }
4002 
4003 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
4004 {
4005 	bool begin_dad = false;
4006 
4007 	spin_lock_bh(&ifp->lock);
4008 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
4009 		ifp->state = INET6_IFADDR_STATE_PREDAD;
4010 		begin_dad = true;
4011 	}
4012 	spin_unlock_bh(&ifp->lock);
4013 
4014 	if (begin_dad)
4015 		addrconf_mod_dad_work(ifp, 0);
4016 }
4017 
4018 static void addrconf_dad_work(struct work_struct *w)
4019 {
4020 	struct inet6_ifaddr *ifp = container_of(to_delayed_work(w),
4021 						struct inet6_ifaddr,
4022 						dad_work);
4023 	struct inet6_dev *idev = ifp->idev;
4024 	bool bump_id, disable_ipv6 = false;
4025 	struct in6_addr mcaddr;
4026 
4027 	enum {
4028 		DAD_PROCESS,
4029 		DAD_BEGIN,
4030 		DAD_ABORT,
4031 	} action = DAD_PROCESS;
4032 
4033 	rtnl_lock();
4034 
4035 	spin_lock_bh(&ifp->lock);
4036 	if (ifp->state == INET6_IFADDR_STATE_PREDAD) {
4037 		action = DAD_BEGIN;
4038 		ifp->state = INET6_IFADDR_STATE_DAD;
4039 	} else if (ifp->state == INET6_IFADDR_STATE_ERRDAD) {
4040 		action = DAD_ABORT;
4041 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
4042 
4043 		if ((dev_net(idev->dev)->ipv6.devconf_all->accept_dad > 1 ||
4044 		     idev->cnf.accept_dad > 1) &&
4045 		    !idev->cnf.disable_ipv6 &&
4046 		    !(ifp->flags & IFA_F_STABLE_PRIVACY)) {
4047 			struct in6_addr addr;
4048 
4049 			addr.s6_addr32[0] = htonl(0xfe800000);
4050 			addr.s6_addr32[1] = 0;
4051 
4052 			if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
4053 			    ipv6_addr_equal(&ifp->addr, &addr)) {
4054 				/* DAD failed for link-local based on MAC */
4055 				idev->cnf.disable_ipv6 = 1;
4056 
4057 				pr_info("%s: IPv6 being disabled!\n",
4058 					ifp->idev->dev->name);
4059 				disable_ipv6 = true;
4060 			}
4061 		}
4062 	}
4063 	spin_unlock_bh(&ifp->lock);
4064 
4065 	if (action == DAD_BEGIN) {
4066 		addrconf_dad_begin(ifp);
4067 		goto out;
4068 	} else if (action == DAD_ABORT) {
4069 		in6_ifa_hold(ifp);
4070 		addrconf_dad_stop(ifp, 1);
4071 		if (disable_ipv6)
4072 			addrconf_ifdown(idev->dev, 0);
4073 		goto out;
4074 	}
4075 
4076 	if (!ifp->dad_probes && addrconf_dad_end(ifp))
4077 		goto out;
4078 
4079 	write_lock_bh(&idev->lock);
4080 	if (idev->dead || !(idev->if_flags & IF_READY)) {
4081 		write_unlock_bh(&idev->lock);
4082 		goto out;
4083 	}
4084 
4085 	spin_lock(&ifp->lock);
4086 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
4087 		spin_unlock(&ifp->lock);
4088 		write_unlock_bh(&idev->lock);
4089 		goto out;
4090 	}
4091 
4092 	if (ifp->dad_probes == 0) {
4093 		bool send_na = false;
4094 
4095 		/*
4096 		 * DAD was successful
4097 		 */
4098 
4099 		if (ifp->flags & IFA_F_TENTATIVE &&
4100 		    !(ifp->flags & IFA_F_OPTIMISTIC))
4101 			send_na = true;
4102 		bump_id = ifp->flags & IFA_F_TENTATIVE;
4103 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
4104 		spin_unlock(&ifp->lock);
4105 		write_unlock_bh(&idev->lock);
4106 
4107 		addrconf_dad_completed(ifp, bump_id, send_na);
4108 
4109 		goto out;
4110 	}
4111 
4112 	ifp->dad_probes--;
4113 	addrconf_mod_dad_work(ifp,
4114 			      NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME));
4115 	spin_unlock(&ifp->lock);
4116 	write_unlock_bh(&idev->lock);
4117 
4118 	/* send a neighbour solicitation for our addr */
4119 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
4120 	ndisc_send_ns(ifp->idev->dev, &ifp->addr, &mcaddr, &in6addr_any,
4121 		      ifp->dad_nonce);
4122 out:
4123 	in6_ifa_put(ifp);
4124 	rtnl_unlock();
4125 }
4126 
4127 /* ifp->idev must be at least read locked */
4128 static bool ipv6_lonely_lladdr(struct inet6_ifaddr *ifp)
4129 {
4130 	struct inet6_ifaddr *ifpiter;
4131 	struct inet6_dev *idev = ifp->idev;
4132 
4133 	list_for_each_entry_reverse(ifpiter, &idev->addr_list, if_list) {
4134 		if (ifpiter->scope > IFA_LINK)
4135 			break;
4136 		if (ifp != ifpiter && ifpiter->scope == IFA_LINK &&
4137 		    (ifpiter->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE|
4138 				       IFA_F_OPTIMISTIC|IFA_F_DADFAILED)) ==
4139 		    IFA_F_PERMANENT)
4140 			return false;
4141 	}
4142 	return true;
4143 }
4144 
4145 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
4146 				   bool send_na)
4147 {
4148 	struct net_device *dev = ifp->idev->dev;
4149 	struct in6_addr lladdr;
4150 	bool send_rs, send_mld;
4151 
4152 	addrconf_del_dad_work(ifp);
4153 
4154 	/*
4155 	 *	Configure the address for reception. Now it is valid.
4156 	 */
4157 
4158 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
4159 
4160 	/* If added prefix is link local and we are prepared to process
4161 	   router advertisements, start sending router solicitations.
4162 	 */
4163 
4164 	read_lock_bh(&ifp->idev->lock);
4165 	send_mld = ifp->scope == IFA_LINK && ipv6_lonely_lladdr(ifp);
4166 	send_rs = send_mld &&
4167 		  ipv6_accept_ra(ifp->idev) &&
4168 		  ifp->idev->cnf.rtr_solicits != 0 &&
4169 		  (dev->flags&IFF_LOOPBACK) == 0;
4170 	read_unlock_bh(&ifp->idev->lock);
4171 
4172 	/* While dad is in progress mld report's source address is in6_addrany.
4173 	 * Resend with proper ll now.
4174 	 */
4175 	if (send_mld)
4176 		ipv6_mc_dad_complete(ifp->idev);
4177 
4178 	/* send unsolicited NA if enabled */
4179 	if (send_na &&
4180 	    (ifp->idev->cnf.ndisc_notify ||
4181 	     dev_net(dev)->ipv6.devconf_all->ndisc_notify)) {
4182 		ndisc_send_na(dev, &in6addr_linklocal_allnodes, &ifp->addr,
4183 			      /*router=*/ !!ifp->idev->cnf.forwarding,
4184 			      /*solicited=*/ false, /*override=*/ true,
4185 			      /*inc_opt=*/ true);
4186 	}
4187 
4188 	if (send_rs) {
4189 		/*
4190 		 *	If a host as already performed a random delay
4191 		 *	[...] as part of DAD [...] there is no need
4192 		 *	to delay again before sending the first RS
4193 		 */
4194 		if (ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4195 			return;
4196 		ndisc_send_rs(dev, &lladdr, &in6addr_linklocal_allrouters);
4197 
4198 		write_lock_bh(&ifp->idev->lock);
4199 		spin_lock(&ifp->lock);
4200 		ifp->idev->rs_interval = rfc3315_s14_backoff_init(
4201 			ifp->idev->cnf.rtr_solicit_interval);
4202 		ifp->idev->rs_probes = 1;
4203 		ifp->idev->if_flags |= IF_RS_SENT;
4204 		addrconf_mod_rs_timer(ifp->idev, ifp->idev->rs_interval);
4205 		spin_unlock(&ifp->lock);
4206 		write_unlock_bh(&ifp->idev->lock);
4207 	}
4208 
4209 	if (bump_id)
4210 		rt_genid_bump_ipv6(dev_net(dev));
4211 
4212 	/* Make sure that a new temporary address will be created
4213 	 * before this temporary address becomes deprecated.
4214 	 */
4215 	if (ifp->flags & IFA_F_TEMPORARY)
4216 		addrconf_verify_rtnl();
4217 }
4218 
4219 static void addrconf_dad_run(struct inet6_dev *idev, bool restart)
4220 {
4221 	struct inet6_ifaddr *ifp;
4222 
4223 	read_lock_bh(&idev->lock);
4224 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
4225 		spin_lock(&ifp->lock);
4226 		if ((ifp->flags & IFA_F_TENTATIVE &&
4227 		     ifp->state == INET6_IFADDR_STATE_DAD) || restart) {
4228 			if (restart)
4229 				ifp->state = INET6_IFADDR_STATE_PREDAD;
4230 			addrconf_dad_kick(ifp);
4231 		}
4232 		spin_unlock(&ifp->lock);
4233 	}
4234 	read_unlock_bh(&idev->lock);
4235 }
4236 
4237 #ifdef CONFIG_PROC_FS
4238 struct if6_iter_state {
4239 	struct seq_net_private p;
4240 	int bucket;
4241 	int offset;
4242 };
4243 
4244 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
4245 {
4246 	struct if6_iter_state *state = seq->private;
4247 	struct net *net = seq_file_net(seq);
4248 	struct inet6_ifaddr *ifa = NULL;
4249 	int p = 0;
4250 
4251 	/* initial bucket if pos is 0 */
4252 	if (pos == 0) {
4253 		state->bucket = 0;
4254 		state->offset = 0;
4255 	}
4256 
4257 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
4258 		hlist_for_each_entry_rcu(ifa, &inet6_addr_lst[state->bucket],
4259 					 addr_lst) {
4260 			if (!net_eq(dev_net(ifa->idev->dev), net))
4261 				continue;
4262 			/* sync with offset */
4263 			if (p < state->offset) {
4264 				p++;
4265 				continue;
4266 			}
4267 			return ifa;
4268 		}
4269 
4270 		/* prepare for next bucket */
4271 		state->offset = 0;
4272 		p = 0;
4273 	}
4274 	return NULL;
4275 }
4276 
4277 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
4278 					 struct inet6_ifaddr *ifa)
4279 {
4280 	struct if6_iter_state *state = seq->private;
4281 	struct net *net = seq_file_net(seq);
4282 
4283 	hlist_for_each_entry_continue_rcu(ifa, addr_lst) {
4284 		if (!net_eq(dev_net(ifa->idev->dev), net))
4285 			continue;
4286 		state->offset++;
4287 		return ifa;
4288 	}
4289 
4290 	state->offset = 0;
4291 	while (++state->bucket < IN6_ADDR_HSIZE) {
4292 		hlist_for_each_entry_rcu(ifa,
4293 				     &inet6_addr_lst[state->bucket], addr_lst) {
4294 			if (!net_eq(dev_net(ifa->idev->dev), net))
4295 				continue;
4296 			return ifa;
4297 		}
4298 	}
4299 
4300 	return NULL;
4301 }
4302 
4303 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
4304 	__acquires(rcu)
4305 {
4306 	rcu_read_lock();
4307 	return if6_get_first(seq, *pos);
4308 }
4309 
4310 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4311 {
4312 	struct inet6_ifaddr *ifa;
4313 
4314 	ifa = if6_get_next(seq, v);
4315 	++*pos;
4316 	return ifa;
4317 }
4318 
4319 static void if6_seq_stop(struct seq_file *seq, void *v)
4320 	__releases(rcu)
4321 {
4322 	rcu_read_unlock();
4323 }
4324 
4325 static int if6_seq_show(struct seq_file *seq, void *v)
4326 {
4327 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
4328 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
4329 		   &ifp->addr,
4330 		   ifp->idev->dev->ifindex,
4331 		   ifp->prefix_len,
4332 		   ifp->scope,
4333 		   (u8) ifp->flags,
4334 		   ifp->idev->dev->name);
4335 	return 0;
4336 }
4337 
4338 static const struct seq_operations if6_seq_ops = {
4339 	.start	= if6_seq_start,
4340 	.next	= if6_seq_next,
4341 	.show	= if6_seq_show,
4342 	.stop	= if6_seq_stop,
4343 };
4344 
4345 static int __net_init if6_proc_net_init(struct net *net)
4346 {
4347 	if (!proc_create_net("if_inet6", 0444, net->proc_net, &if6_seq_ops,
4348 			sizeof(struct if6_iter_state)))
4349 		return -ENOMEM;
4350 	return 0;
4351 }
4352 
4353 static void __net_exit if6_proc_net_exit(struct net *net)
4354 {
4355 	remove_proc_entry("if_inet6", net->proc_net);
4356 }
4357 
4358 static struct pernet_operations if6_proc_net_ops = {
4359 	.init = if6_proc_net_init,
4360 	.exit = if6_proc_net_exit,
4361 };
4362 
4363 int __init if6_proc_init(void)
4364 {
4365 	return register_pernet_subsys(&if6_proc_net_ops);
4366 }
4367 
4368 void if6_proc_exit(void)
4369 {
4370 	unregister_pernet_subsys(&if6_proc_net_ops);
4371 }
4372 #endif	/* CONFIG_PROC_FS */
4373 
4374 #if IS_ENABLED(CONFIG_IPV6_MIP6)
4375 /* Check if address is a home address configured on any interface. */
4376 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
4377 {
4378 	unsigned int hash = inet6_addr_hash(net, addr);
4379 	struct inet6_ifaddr *ifp = NULL;
4380 	int ret = 0;
4381 
4382 	rcu_read_lock();
4383 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
4384 		if (!net_eq(dev_net(ifp->idev->dev), net))
4385 			continue;
4386 		if (ipv6_addr_equal(&ifp->addr, addr) &&
4387 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
4388 			ret = 1;
4389 			break;
4390 		}
4391 	}
4392 	rcu_read_unlock();
4393 	return ret;
4394 }
4395 #endif
4396 
4397 /*
4398  *	Periodic address status verification
4399  */
4400 
4401 static void addrconf_verify_rtnl(void)
4402 {
4403 	unsigned long now, next, next_sec, next_sched;
4404 	struct inet6_ifaddr *ifp;
4405 	int i;
4406 
4407 	ASSERT_RTNL();
4408 
4409 	rcu_read_lock_bh();
4410 	now = jiffies;
4411 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
4412 
4413 	cancel_delayed_work(&addr_chk_work);
4414 
4415 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
4416 restart:
4417 		hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[i], addr_lst) {
4418 			unsigned long age;
4419 
4420 			/* When setting preferred_lft to a value not zero or
4421 			 * infinity, while valid_lft is infinity
4422 			 * IFA_F_PERMANENT has a non-infinity life time.
4423 			 */
4424 			if ((ifp->flags & IFA_F_PERMANENT) &&
4425 			    (ifp->prefered_lft == INFINITY_LIFE_TIME))
4426 				continue;
4427 
4428 			spin_lock(&ifp->lock);
4429 			/* We try to batch several events at once. */
4430 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
4431 
4432 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
4433 			    age >= ifp->valid_lft) {
4434 				spin_unlock(&ifp->lock);
4435 				in6_ifa_hold(ifp);
4436 				ipv6_del_addr(ifp);
4437 				goto restart;
4438 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
4439 				spin_unlock(&ifp->lock);
4440 				continue;
4441 			} else if (age >= ifp->prefered_lft) {
4442 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
4443 				int deprecate = 0;
4444 
4445 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
4446 					deprecate = 1;
4447 					ifp->flags |= IFA_F_DEPRECATED;
4448 				}
4449 
4450 				if ((ifp->valid_lft != INFINITY_LIFE_TIME) &&
4451 				    (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)))
4452 					next = ifp->tstamp + ifp->valid_lft * HZ;
4453 
4454 				spin_unlock(&ifp->lock);
4455 
4456 				if (deprecate) {
4457 					in6_ifa_hold(ifp);
4458 
4459 					ipv6_ifa_notify(0, ifp);
4460 					in6_ifa_put(ifp);
4461 					goto restart;
4462 				}
4463 			} else if ((ifp->flags&IFA_F_TEMPORARY) &&
4464 				   !(ifp->flags&IFA_F_TENTATIVE)) {
4465 				unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
4466 					ifp->idev->cnf.dad_transmits *
4467 					NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME) / HZ;
4468 
4469 				if (age >= ifp->prefered_lft - regen_advance) {
4470 					struct inet6_ifaddr *ifpub = ifp->ifpub;
4471 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4472 						next = ifp->tstamp + ifp->prefered_lft * HZ;
4473 					if (!ifp->regen_count && ifpub) {
4474 						ifp->regen_count++;
4475 						in6_ifa_hold(ifp);
4476 						in6_ifa_hold(ifpub);
4477 						spin_unlock(&ifp->lock);
4478 
4479 						spin_lock(&ifpub->lock);
4480 						ifpub->regen_count = 0;
4481 						spin_unlock(&ifpub->lock);
4482 						rcu_read_unlock_bh();
4483 						ipv6_create_tempaddr(ifpub, ifp, true);
4484 						in6_ifa_put(ifpub);
4485 						in6_ifa_put(ifp);
4486 						rcu_read_lock_bh();
4487 						goto restart;
4488 					}
4489 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
4490 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
4491 				spin_unlock(&ifp->lock);
4492 			} else {
4493 				/* ifp->prefered_lft <= ifp->valid_lft */
4494 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4495 					next = ifp->tstamp + ifp->prefered_lft * HZ;
4496 				spin_unlock(&ifp->lock);
4497 			}
4498 		}
4499 	}
4500 
4501 	next_sec = round_jiffies_up(next);
4502 	next_sched = next;
4503 
4504 	/* If rounded timeout is accurate enough, accept it. */
4505 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
4506 		next_sched = next_sec;
4507 
4508 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
4509 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
4510 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
4511 
4512 	pr_debug("now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
4513 		 now, next, next_sec, next_sched);
4514 	mod_delayed_work(addrconf_wq, &addr_chk_work, next_sched - now);
4515 	rcu_read_unlock_bh();
4516 }
4517 
4518 static void addrconf_verify_work(struct work_struct *w)
4519 {
4520 	rtnl_lock();
4521 	addrconf_verify_rtnl();
4522 	rtnl_unlock();
4523 }
4524 
4525 static void addrconf_verify(void)
4526 {
4527 	mod_delayed_work(addrconf_wq, &addr_chk_work, 0);
4528 }
4529 
4530 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
4531 				     struct in6_addr **peer_pfx)
4532 {
4533 	struct in6_addr *pfx = NULL;
4534 
4535 	*peer_pfx = NULL;
4536 
4537 	if (addr)
4538 		pfx = nla_data(addr);
4539 
4540 	if (local) {
4541 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
4542 			*peer_pfx = pfx;
4543 		pfx = nla_data(local);
4544 	}
4545 
4546 	return pfx;
4547 }
4548 
4549 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
4550 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
4551 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
4552 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
4553 	[IFA_FLAGS]		= { .len = sizeof(u32) },
4554 	[IFA_RT_PRIORITY]	= { .len = sizeof(u32) },
4555 	[IFA_TARGET_NETNSID]	= { .type = NLA_S32 },
4556 };
4557 
4558 static int
4559 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh,
4560 		  struct netlink_ext_ack *extack)
4561 {
4562 	struct net *net = sock_net(skb->sk);
4563 	struct ifaddrmsg *ifm;
4564 	struct nlattr *tb[IFA_MAX+1];
4565 	struct in6_addr *pfx, *peer_pfx;
4566 	u32 ifa_flags;
4567 	int err;
4568 
4569 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
4570 				     ifa_ipv6_policy, extack);
4571 	if (err < 0)
4572 		return err;
4573 
4574 	ifm = nlmsg_data(nlh);
4575 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4576 	if (!pfx)
4577 		return -EINVAL;
4578 
4579 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
4580 
4581 	/* We ignore other flags so far. */
4582 	ifa_flags &= IFA_F_MANAGETEMPADDR;
4583 
4584 	return inet6_addr_del(net, ifm->ifa_index, ifa_flags, pfx,
4585 			      ifm->ifa_prefixlen);
4586 }
4587 
4588 static int modify_prefix_route(struct inet6_ifaddr *ifp,
4589 			       unsigned long expires, u32 flags)
4590 {
4591 	struct fib6_info *f6i;
4592 	u32 prio;
4593 
4594 	f6i = addrconf_get_prefix_route(&ifp->addr, ifp->prefix_len,
4595 					ifp->idev->dev, 0, RTF_DEFAULT, true);
4596 	if (!f6i)
4597 		return -ENOENT;
4598 
4599 	prio = ifp->rt_priority ? : IP6_RT_PRIO_ADDRCONF;
4600 	if (f6i->fib6_metric != prio) {
4601 		/* delete old one */
4602 		ip6_del_rt(dev_net(ifp->idev->dev), f6i);
4603 
4604 		/* add new one */
4605 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
4606 				      ifp->rt_priority, ifp->idev->dev,
4607 				      expires, flags, GFP_KERNEL);
4608 	} else {
4609 		if (!expires)
4610 			fib6_clean_expires(f6i);
4611 		else
4612 			fib6_set_expires(f6i, expires);
4613 
4614 		fib6_info_release(f6i);
4615 	}
4616 
4617 	return 0;
4618 }
4619 
4620 static int inet6_addr_modify(struct inet6_ifaddr *ifp, struct ifa6_config *cfg)
4621 {
4622 	u32 flags;
4623 	clock_t expires;
4624 	unsigned long timeout;
4625 	bool was_managetempaddr;
4626 	bool had_prefixroute;
4627 
4628 	ASSERT_RTNL();
4629 
4630 	if (!cfg->valid_lft || cfg->preferred_lft > cfg->valid_lft)
4631 		return -EINVAL;
4632 
4633 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR &&
4634 	    (ifp->flags & IFA_F_TEMPORARY || ifp->prefix_len != 64))
4635 		return -EINVAL;
4636 
4637 	if (!(ifp->flags & IFA_F_TENTATIVE) || ifp->flags & IFA_F_DADFAILED)
4638 		cfg->ifa_flags &= ~IFA_F_OPTIMISTIC;
4639 
4640 	timeout = addrconf_timeout_fixup(cfg->valid_lft, HZ);
4641 	if (addrconf_finite_timeout(timeout)) {
4642 		expires = jiffies_to_clock_t(timeout * HZ);
4643 		cfg->valid_lft = timeout;
4644 		flags = RTF_EXPIRES;
4645 	} else {
4646 		expires = 0;
4647 		flags = 0;
4648 		cfg->ifa_flags |= IFA_F_PERMANENT;
4649 	}
4650 
4651 	timeout = addrconf_timeout_fixup(cfg->preferred_lft, HZ);
4652 	if (addrconf_finite_timeout(timeout)) {
4653 		if (timeout == 0)
4654 			cfg->ifa_flags |= IFA_F_DEPRECATED;
4655 		cfg->preferred_lft = timeout;
4656 	}
4657 
4658 	spin_lock_bh(&ifp->lock);
4659 	was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;
4660 	had_prefixroute = ifp->flags & IFA_F_PERMANENT &&
4661 			  !(ifp->flags & IFA_F_NOPREFIXROUTE);
4662 	ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |
4663 			IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4664 			IFA_F_NOPREFIXROUTE);
4665 	ifp->flags |= cfg->ifa_flags;
4666 	ifp->tstamp = jiffies;
4667 	ifp->valid_lft = cfg->valid_lft;
4668 	ifp->prefered_lft = cfg->preferred_lft;
4669 
4670 	if (cfg->rt_priority && cfg->rt_priority != ifp->rt_priority)
4671 		ifp->rt_priority = cfg->rt_priority;
4672 
4673 	spin_unlock_bh(&ifp->lock);
4674 	if (!(ifp->flags&IFA_F_TENTATIVE))
4675 		ipv6_ifa_notify(0, ifp);
4676 
4677 	if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
4678 		int rc = -ENOENT;
4679 
4680 		if (had_prefixroute)
4681 			rc = modify_prefix_route(ifp, expires, flags);
4682 
4683 		/* prefix route could have been deleted; if so restore it */
4684 		if (rc == -ENOENT) {
4685 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
4686 					      ifp->rt_priority, ifp->idev->dev,
4687 					      expires, flags, GFP_KERNEL);
4688 		}
4689 	} else if (had_prefixroute) {
4690 		enum cleanup_prefix_rt_t action;
4691 		unsigned long rt_expires;
4692 
4693 		write_lock_bh(&ifp->idev->lock);
4694 		action = check_cleanup_prefix_route(ifp, &rt_expires);
4695 		write_unlock_bh(&ifp->idev->lock);
4696 
4697 		if (action != CLEANUP_PREFIX_RT_NOP) {
4698 			cleanup_prefix_route(ifp, rt_expires,
4699 				action == CLEANUP_PREFIX_RT_DEL);
4700 		}
4701 	}
4702 
4703 	if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {
4704 		if (was_managetempaddr &&
4705 		    !(ifp->flags & IFA_F_MANAGETEMPADDR)) {
4706 			cfg->valid_lft = 0;
4707 			cfg->preferred_lft = 0;
4708 		}
4709 		manage_tempaddrs(ifp->idev, ifp, cfg->valid_lft,
4710 				 cfg->preferred_lft, !was_managetempaddr,
4711 				 jiffies);
4712 	}
4713 
4714 	addrconf_verify_rtnl();
4715 
4716 	return 0;
4717 }
4718 
4719 static int
4720 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
4721 		  struct netlink_ext_ack *extack)
4722 {
4723 	struct net *net = sock_net(skb->sk);
4724 	struct ifaddrmsg *ifm;
4725 	struct nlattr *tb[IFA_MAX+1];
4726 	struct in6_addr *peer_pfx;
4727 	struct inet6_ifaddr *ifa;
4728 	struct net_device *dev;
4729 	struct inet6_dev *idev;
4730 	struct ifa6_config cfg;
4731 	int err;
4732 
4733 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
4734 				     ifa_ipv6_policy, extack);
4735 	if (err < 0)
4736 		return err;
4737 
4738 	memset(&cfg, 0, sizeof(cfg));
4739 
4740 	ifm = nlmsg_data(nlh);
4741 	cfg.pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4742 	if (!cfg.pfx)
4743 		return -EINVAL;
4744 
4745 	cfg.peer_pfx = peer_pfx;
4746 	cfg.plen = ifm->ifa_prefixlen;
4747 	if (tb[IFA_RT_PRIORITY])
4748 		cfg.rt_priority = nla_get_u32(tb[IFA_RT_PRIORITY]);
4749 
4750 	cfg.valid_lft = INFINITY_LIFE_TIME;
4751 	cfg.preferred_lft = INFINITY_LIFE_TIME;
4752 
4753 	if (tb[IFA_CACHEINFO]) {
4754 		struct ifa_cacheinfo *ci;
4755 
4756 		ci = nla_data(tb[IFA_CACHEINFO]);
4757 		cfg.valid_lft = ci->ifa_valid;
4758 		cfg.preferred_lft = ci->ifa_prefered;
4759 	}
4760 
4761 	dev =  __dev_get_by_index(net, ifm->ifa_index);
4762 	if (!dev)
4763 		return -ENODEV;
4764 
4765 	if (tb[IFA_FLAGS])
4766 		cfg.ifa_flags = nla_get_u32(tb[IFA_FLAGS]);
4767 	else
4768 		cfg.ifa_flags = ifm->ifa_flags;
4769 
4770 	/* We ignore other flags so far. */
4771 	cfg.ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS |
4772 			 IFA_F_MANAGETEMPADDR | IFA_F_NOPREFIXROUTE |
4773 			 IFA_F_MCAUTOJOIN | IFA_F_OPTIMISTIC;
4774 
4775 	idev = ipv6_find_idev(dev);
4776 	if (IS_ERR(idev))
4777 		return PTR_ERR(idev);
4778 
4779 	if (!ipv6_allow_optimistic_dad(net, idev))
4780 		cfg.ifa_flags &= ~IFA_F_OPTIMISTIC;
4781 
4782 	if (cfg.ifa_flags & IFA_F_NODAD &&
4783 	    cfg.ifa_flags & IFA_F_OPTIMISTIC) {
4784 		NL_SET_ERR_MSG(extack, "IFA_F_NODAD and IFA_F_OPTIMISTIC are mutually exclusive");
4785 		return -EINVAL;
4786 	}
4787 
4788 	ifa = ipv6_get_ifaddr(net, cfg.pfx, dev, 1);
4789 	if (!ifa) {
4790 		/*
4791 		 * It would be best to check for !NLM_F_CREATE here but
4792 		 * userspace already relies on not having to provide this.
4793 		 */
4794 		return inet6_addr_add(net, ifm->ifa_index, &cfg, extack);
4795 	}
4796 
4797 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
4798 	    !(nlh->nlmsg_flags & NLM_F_REPLACE))
4799 		err = -EEXIST;
4800 	else
4801 		err = inet6_addr_modify(ifa, &cfg);
4802 
4803 	in6_ifa_put(ifa);
4804 
4805 	return err;
4806 }
4807 
4808 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u32 flags,
4809 			  u8 scope, int ifindex)
4810 {
4811 	struct ifaddrmsg *ifm;
4812 
4813 	ifm = nlmsg_data(nlh);
4814 	ifm->ifa_family = AF_INET6;
4815 	ifm->ifa_prefixlen = prefixlen;
4816 	ifm->ifa_flags = flags;
4817 	ifm->ifa_scope = scope;
4818 	ifm->ifa_index = ifindex;
4819 }
4820 
4821 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
4822 			 unsigned long tstamp, u32 preferred, u32 valid)
4823 {
4824 	struct ifa_cacheinfo ci;
4825 
4826 	ci.cstamp = cstamp_delta(cstamp);
4827 	ci.tstamp = cstamp_delta(tstamp);
4828 	ci.ifa_prefered = preferred;
4829 	ci.ifa_valid = valid;
4830 
4831 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
4832 }
4833 
4834 static inline int rt_scope(int ifa_scope)
4835 {
4836 	if (ifa_scope & IFA_HOST)
4837 		return RT_SCOPE_HOST;
4838 	else if (ifa_scope & IFA_LINK)
4839 		return RT_SCOPE_LINK;
4840 	else if (ifa_scope & IFA_SITE)
4841 		return RT_SCOPE_SITE;
4842 	else
4843 		return RT_SCOPE_UNIVERSE;
4844 }
4845 
4846 static inline int inet6_ifaddr_msgsize(void)
4847 {
4848 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
4849 	       + nla_total_size(16) /* IFA_LOCAL */
4850 	       + nla_total_size(16) /* IFA_ADDRESS */
4851 	       + nla_total_size(sizeof(struct ifa_cacheinfo))
4852 	       + nla_total_size(4)  /* IFA_FLAGS */
4853 	       + nla_total_size(4)  /* IFA_RT_PRIORITY */;
4854 }
4855 
4856 enum addr_type_t {
4857 	UNICAST_ADDR,
4858 	MULTICAST_ADDR,
4859 	ANYCAST_ADDR,
4860 };
4861 
4862 struct inet6_fill_args {
4863 	u32 portid;
4864 	u32 seq;
4865 	int event;
4866 	unsigned int flags;
4867 	int netnsid;
4868 	int ifindex;
4869 	enum addr_type_t type;
4870 };
4871 
4872 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
4873 			     struct inet6_fill_args *args)
4874 {
4875 	struct nlmsghdr  *nlh;
4876 	u32 preferred, valid;
4877 
4878 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
4879 			sizeof(struct ifaddrmsg), args->flags);
4880 	if (!nlh)
4881 		return -EMSGSIZE;
4882 
4883 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
4884 		      ifa->idev->dev->ifindex);
4885 
4886 	if (args->netnsid >= 0 &&
4887 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
4888 		goto error;
4889 
4890 	if (!((ifa->flags&IFA_F_PERMANENT) &&
4891 	      (ifa->prefered_lft == INFINITY_LIFE_TIME))) {
4892 		preferred = ifa->prefered_lft;
4893 		valid = ifa->valid_lft;
4894 		if (preferred != INFINITY_LIFE_TIME) {
4895 			long tval = (jiffies - ifa->tstamp)/HZ;
4896 			if (preferred > tval)
4897 				preferred -= tval;
4898 			else
4899 				preferred = 0;
4900 			if (valid != INFINITY_LIFE_TIME) {
4901 				if (valid > tval)
4902 					valid -= tval;
4903 				else
4904 					valid = 0;
4905 			}
4906 		}
4907 	} else {
4908 		preferred = INFINITY_LIFE_TIME;
4909 		valid = INFINITY_LIFE_TIME;
4910 	}
4911 
4912 	if (!ipv6_addr_any(&ifa->peer_addr)) {
4913 		if (nla_put_in6_addr(skb, IFA_LOCAL, &ifa->addr) < 0 ||
4914 		    nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->peer_addr) < 0)
4915 			goto error;
4916 	} else
4917 		if (nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->addr) < 0)
4918 			goto error;
4919 
4920 	if (ifa->rt_priority &&
4921 	    nla_put_u32(skb, IFA_RT_PRIORITY, ifa->rt_priority))
4922 		goto error;
4923 
4924 	if (put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0)
4925 		goto error;
4926 
4927 	if (nla_put_u32(skb, IFA_FLAGS, ifa->flags) < 0)
4928 		goto error;
4929 
4930 	nlmsg_end(skb, nlh);
4931 	return 0;
4932 
4933 error:
4934 	nlmsg_cancel(skb, nlh);
4935 	return -EMSGSIZE;
4936 }
4937 
4938 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
4939 			       struct inet6_fill_args *args)
4940 {
4941 	struct nlmsghdr  *nlh;
4942 	u8 scope = RT_SCOPE_UNIVERSE;
4943 	int ifindex = ifmca->idev->dev->ifindex;
4944 
4945 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
4946 		scope = RT_SCOPE_SITE;
4947 
4948 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
4949 			sizeof(struct ifaddrmsg), args->flags);
4950 	if (!nlh)
4951 		return -EMSGSIZE;
4952 
4953 	if (args->netnsid >= 0 &&
4954 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
4955 		return -EMSGSIZE;
4956 
4957 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4958 	if (nla_put_in6_addr(skb, IFA_MULTICAST, &ifmca->mca_addr) < 0 ||
4959 	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
4960 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4961 		nlmsg_cancel(skb, nlh);
4962 		return -EMSGSIZE;
4963 	}
4964 
4965 	nlmsg_end(skb, nlh);
4966 	return 0;
4967 }
4968 
4969 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
4970 			       struct inet6_fill_args *args)
4971 {
4972 	struct net_device *dev = fib6_info_nh_dev(ifaca->aca_rt);
4973 	int ifindex = dev ? dev->ifindex : 1;
4974 	struct nlmsghdr  *nlh;
4975 	u8 scope = RT_SCOPE_UNIVERSE;
4976 
4977 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
4978 		scope = RT_SCOPE_SITE;
4979 
4980 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
4981 			sizeof(struct ifaddrmsg), args->flags);
4982 	if (!nlh)
4983 		return -EMSGSIZE;
4984 
4985 	if (args->netnsid >= 0 &&
4986 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
4987 		return -EMSGSIZE;
4988 
4989 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4990 	if (nla_put_in6_addr(skb, IFA_ANYCAST, &ifaca->aca_addr) < 0 ||
4991 	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
4992 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4993 		nlmsg_cancel(skb, nlh);
4994 		return -EMSGSIZE;
4995 	}
4996 
4997 	nlmsg_end(skb, nlh);
4998 	return 0;
4999 }
5000 
5001 /* called with rcu_read_lock() */
5002 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
5003 			  struct netlink_callback *cb, int s_ip_idx,
5004 			  struct inet6_fill_args *fillargs)
5005 {
5006 	struct ifmcaddr6 *ifmca;
5007 	struct ifacaddr6 *ifaca;
5008 	int ip_idx = 0;
5009 	int err = 1;
5010 
5011 	read_lock_bh(&idev->lock);
5012 	switch (fillargs->type) {
5013 	case UNICAST_ADDR: {
5014 		struct inet6_ifaddr *ifa;
5015 		fillargs->event = RTM_NEWADDR;
5016 
5017 		/* unicast address incl. temp addr */
5018 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
5019 			if (ip_idx < s_ip_idx)
5020 				goto next;
5021 			err = inet6_fill_ifaddr(skb, ifa, fillargs);
5022 			if (err < 0)
5023 				break;
5024 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
5025 next:
5026 			ip_idx++;
5027 		}
5028 		break;
5029 	}
5030 	case MULTICAST_ADDR:
5031 		fillargs->event = RTM_GETMULTICAST;
5032 
5033 		/* multicast address */
5034 		for (ifmca = idev->mc_list; ifmca;
5035 		     ifmca = ifmca->next, ip_idx++) {
5036 			if (ip_idx < s_ip_idx)
5037 				continue;
5038 			err = inet6_fill_ifmcaddr(skb, ifmca, fillargs);
5039 			if (err < 0)
5040 				break;
5041 		}
5042 		break;
5043 	case ANYCAST_ADDR:
5044 		fillargs->event = RTM_GETANYCAST;
5045 		/* anycast address */
5046 		for (ifaca = idev->ac_list; ifaca;
5047 		     ifaca = ifaca->aca_next, ip_idx++) {
5048 			if (ip_idx < s_ip_idx)
5049 				continue;
5050 			err = inet6_fill_ifacaddr(skb, ifaca, fillargs);
5051 			if (err < 0)
5052 				break;
5053 		}
5054 		break;
5055 	default:
5056 		break;
5057 	}
5058 	read_unlock_bh(&idev->lock);
5059 	cb->args[2] = ip_idx;
5060 	return err;
5061 }
5062 
5063 static int inet6_valid_dump_ifaddr_req(const struct nlmsghdr *nlh,
5064 				       struct inet6_fill_args *fillargs,
5065 				       struct net **tgt_net, struct sock *sk,
5066 				       struct netlink_callback *cb)
5067 {
5068 	struct netlink_ext_ack *extack = cb->extack;
5069 	struct nlattr *tb[IFA_MAX+1];
5070 	struct ifaddrmsg *ifm;
5071 	int err, i;
5072 
5073 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5074 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for address dump request");
5075 		return -EINVAL;
5076 	}
5077 
5078 	ifm = nlmsg_data(nlh);
5079 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5080 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for address dump request");
5081 		return -EINVAL;
5082 	}
5083 
5084 	fillargs->ifindex = ifm->ifa_index;
5085 	if (fillargs->ifindex) {
5086 		cb->answer_flags |= NLM_F_DUMP_FILTERED;
5087 		fillargs->flags |= NLM_F_DUMP_FILTERED;
5088 	}
5089 
5090 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5091 					    ifa_ipv6_policy, extack);
5092 	if (err < 0)
5093 		return err;
5094 
5095 	for (i = 0; i <= IFA_MAX; ++i) {
5096 		if (!tb[i])
5097 			continue;
5098 
5099 		if (i == IFA_TARGET_NETNSID) {
5100 			struct net *net;
5101 
5102 			fillargs->netnsid = nla_get_s32(tb[i]);
5103 			net = rtnl_get_net_ns_capable(sk, fillargs->netnsid);
5104 			if (IS_ERR(net)) {
5105 				fillargs->netnsid = -1;
5106 				NL_SET_ERR_MSG_MOD(extack, "Invalid target network namespace id");
5107 				return PTR_ERR(net);
5108 			}
5109 			*tgt_net = net;
5110 		} else {
5111 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in dump request");
5112 			return -EINVAL;
5113 		}
5114 	}
5115 
5116 	return 0;
5117 }
5118 
5119 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
5120 			   enum addr_type_t type)
5121 {
5122 	const struct nlmsghdr *nlh = cb->nlh;
5123 	struct inet6_fill_args fillargs = {
5124 		.portid = NETLINK_CB(cb->skb).portid,
5125 		.seq = cb->nlh->nlmsg_seq,
5126 		.flags = NLM_F_MULTI,
5127 		.netnsid = -1,
5128 		.type = type,
5129 	};
5130 	struct net *net = sock_net(skb->sk);
5131 	struct net *tgt_net = net;
5132 	int idx, s_idx, s_ip_idx;
5133 	int h, s_h;
5134 	struct net_device *dev;
5135 	struct inet6_dev *idev;
5136 	struct hlist_head *head;
5137 	int err = 0;
5138 
5139 	s_h = cb->args[0];
5140 	s_idx = idx = cb->args[1];
5141 	s_ip_idx = cb->args[2];
5142 
5143 	if (cb->strict_check) {
5144 		err = inet6_valid_dump_ifaddr_req(nlh, &fillargs, &tgt_net,
5145 						  skb->sk, cb);
5146 		if (err < 0)
5147 			goto put_tgt_net;
5148 
5149 		err = 0;
5150 		if (fillargs.ifindex) {
5151 			dev = __dev_get_by_index(tgt_net, fillargs.ifindex);
5152 			if (!dev) {
5153 				err = -ENODEV;
5154 				goto put_tgt_net;
5155 			}
5156 			idev = __in6_dev_get(dev);
5157 			if (idev) {
5158 				err = in6_dump_addrs(idev, skb, cb, s_ip_idx,
5159 						     &fillargs);
5160 				if (err > 0)
5161 					err = 0;
5162 			}
5163 			goto put_tgt_net;
5164 		}
5165 	}
5166 
5167 	rcu_read_lock();
5168 	cb->seq = atomic_read(&tgt_net->ipv6.dev_addr_genid) ^ tgt_net->dev_base_seq;
5169 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
5170 		idx = 0;
5171 		head = &tgt_net->dev_index_head[h];
5172 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
5173 			if (idx < s_idx)
5174 				goto cont;
5175 			if (h > s_h || idx > s_idx)
5176 				s_ip_idx = 0;
5177 			idev = __in6_dev_get(dev);
5178 			if (!idev)
5179 				goto cont;
5180 
5181 			if (in6_dump_addrs(idev, skb, cb, s_ip_idx,
5182 					   &fillargs) < 0)
5183 				goto done;
5184 cont:
5185 			idx++;
5186 		}
5187 	}
5188 done:
5189 	rcu_read_unlock();
5190 	cb->args[0] = h;
5191 	cb->args[1] = idx;
5192 put_tgt_net:
5193 	if (fillargs.netnsid >= 0)
5194 		put_net(tgt_net);
5195 
5196 	return skb->len ? : err;
5197 }
5198 
5199 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
5200 {
5201 	enum addr_type_t type = UNICAST_ADDR;
5202 
5203 	return inet6_dump_addr(skb, cb, type);
5204 }
5205 
5206 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
5207 {
5208 	enum addr_type_t type = MULTICAST_ADDR;
5209 
5210 	return inet6_dump_addr(skb, cb, type);
5211 }
5212 
5213 
5214 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
5215 {
5216 	enum addr_type_t type = ANYCAST_ADDR;
5217 
5218 	return inet6_dump_addr(skb, cb, type);
5219 }
5220 
5221 static int inet6_rtm_valid_getaddr_req(struct sk_buff *skb,
5222 				       const struct nlmsghdr *nlh,
5223 				       struct nlattr **tb,
5224 				       struct netlink_ext_ack *extack)
5225 {
5226 	struct ifaddrmsg *ifm;
5227 	int i, err;
5228 
5229 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5230 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for get address request");
5231 		return -EINVAL;
5232 	}
5233 
5234 	if (!netlink_strict_get_check(skb))
5235 		return nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
5236 					      ifa_ipv6_policy, extack);
5237 
5238 	ifm = nlmsg_data(nlh);
5239 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5240 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for get address request");
5241 		return -EINVAL;
5242 	}
5243 
5244 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5245 					    ifa_ipv6_policy, extack);
5246 	if (err)
5247 		return err;
5248 
5249 	for (i = 0; i <= IFA_MAX; i++) {
5250 		if (!tb[i])
5251 			continue;
5252 
5253 		switch (i) {
5254 		case IFA_TARGET_NETNSID:
5255 		case IFA_ADDRESS:
5256 		case IFA_LOCAL:
5257 			break;
5258 		default:
5259 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in get address request");
5260 			return -EINVAL;
5261 		}
5262 	}
5263 
5264 	return 0;
5265 }
5266 
5267 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
5268 			     struct netlink_ext_ack *extack)
5269 {
5270 	struct net *net = sock_net(in_skb->sk);
5271 	struct inet6_fill_args fillargs = {
5272 		.portid = NETLINK_CB(in_skb).portid,
5273 		.seq = nlh->nlmsg_seq,
5274 		.event = RTM_NEWADDR,
5275 		.flags = 0,
5276 		.netnsid = -1,
5277 	};
5278 	struct net *tgt_net = net;
5279 	struct ifaddrmsg *ifm;
5280 	struct nlattr *tb[IFA_MAX+1];
5281 	struct in6_addr *addr = NULL, *peer;
5282 	struct net_device *dev = NULL;
5283 	struct inet6_ifaddr *ifa;
5284 	struct sk_buff *skb;
5285 	int err;
5286 
5287 	err = inet6_rtm_valid_getaddr_req(in_skb, nlh, tb, extack);
5288 	if (err < 0)
5289 		return err;
5290 
5291 	if (tb[IFA_TARGET_NETNSID]) {
5292 		fillargs.netnsid = nla_get_s32(tb[IFA_TARGET_NETNSID]);
5293 
5294 		tgt_net = rtnl_get_net_ns_capable(NETLINK_CB(in_skb).sk,
5295 						  fillargs.netnsid);
5296 		if (IS_ERR(tgt_net))
5297 			return PTR_ERR(tgt_net);
5298 	}
5299 
5300 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
5301 	if (!addr)
5302 		return -EINVAL;
5303 
5304 	ifm = nlmsg_data(nlh);
5305 	if (ifm->ifa_index)
5306 		dev = dev_get_by_index(tgt_net, ifm->ifa_index);
5307 
5308 	ifa = ipv6_get_ifaddr(tgt_net, addr, dev, 1);
5309 	if (!ifa) {
5310 		err = -EADDRNOTAVAIL;
5311 		goto errout;
5312 	}
5313 
5314 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
5315 	if (!skb) {
5316 		err = -ENOBUFS;
5317 		goto errout_ifa;
5318 	}
5319 
5320 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5321 	if (err < 0) {
5322 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5323 		WARN_ON(err == -EMSGSIZE);
5324 		kfree_skb(skb);
5325 		goto errout_ifa;
5326 	}
5327 	err = rtnl_unicast(skb, tgt_net, NETLINK_CB(in_skb).portid);
5328 errout_ifa:
5329 	in6_ifa_put(ifa);
5330 errout:
5331 	if (dev)
5332 		dev_put(dev);
5333 	if (fillargs.netnsid >= 0)
5334 		put_net(tgt_net);
5335 
5336 	return err;
5337 }
5338 
5339 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
5340 {
5341 	struct sk_buff *skb;
5342 	struct net *net = dev_net(ifa->idev->dev);
5343 	struct inet6_fill_args fillargs = {
5344 		.portid = 0,
5345 		.seq = 0,
5346 		.event = event,
5347 		.flags = 0,
5348 		.netnsid = -1,
5349 	};
5350 	int err = -ENOBUFS;
5351 
5352 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
5353 	if (!skb)
5354 		goto errout;
5355 
5356 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5357 	if (err < 0) {
5358 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5359 		WARN_ON(err == -EMSGSIZE);
5360 		kfree_skb(skb);
5361 		goto errout;
5362 	}
5363 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
5364 	return;
5365 errout:
5366 	if (err < 0)
5367 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
5368 }
5369 
5370 static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
5371 				__s32 *array, int bytes)
5372 {
5373 	BUG_ON(bytes < (DEVCONF_MAX * 4));
5374 
5375 	memset(array, 0, bytes);
5376 	array[DEVCONF_FORWARDING] = cnf->forwarding;
5377 	array[DEVCONF_HOPLIMIT] = cnf->hop_limit;
5378 	array[DEVCONF_MTU6] = cnf->mtu6;
5379 	array[DEVCONF_ACCEPT_RA] = cnf->accept_ra;
5380 	array[DEVCONF_ACCEPT_REDIRECTS] = cnf->accept_redirects;
5381 	array[DEVCONF_AUTOCONF] = cnf->autoconf;
5382 	array[DEVCONF_DAD_TRANSMITS] = cnf->dad_transmits;
5383 	array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
5384 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
5385 		jiffies_to_msecs(cnf->rtr_solicit_interval);
5386 	array[DEVCONF_RTR_SOLICIT_MAX_INTERVAL] =
5387 		jiffies_to_msecs(cnf->rtr_solicit_max_interval);
5388 	array[DEVCONF_RTR_SOLICIT_DELAY] =
5389 		jiffies_to_msecs(cnf->rtr_solicit_delay);
5390 	array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;
5391 	array[DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL] =
5392 		jiffies_to_msecs(cnf->mldv1_unsolicited_report_interval);
5393 	array[DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL] =
5394 		jiffies_to_msecs(cnf->mldv2_unsolicited_report_interval);
5395 	array[DEVCONF_USE_TEMPADDR] = cnf->use_tempaddr;
5396 	array[DEVCONF_TEMP_VALID_LFT] = cnf->temp_valid_lft;
5397 	array[DEVCONF_TEMP_PREFERED_LFT] = cnf->temp_prefered_lft;
5398 	array[DEVCONF_REGEN_MAX_RETRY] = cnf->regen_max_retry;
5399 	array[DEVCONF_MAX_DESYNC_FACTOR] = cnf->max_desync_factor;
5400 	array[DEVCONF_MAX_ADDRESSES] = cnf->max_addresses;
5401 	array[DEVCONF_ACCEPT_RA_DEFRTR] = cnf->accept_ra_defrtr;
5402 	array[DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT] = cnf->accept_ra_min_hop_limit;
5403 	array[DEVCONF_ACCEPT_RA_PINFO] = cnf->accept_ra_pinfo;
5404 #ifdef CONFIG_IPV6_ROUTER_PREF
5405 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = cnf->accept_ra_rtr_pref;
5406 	array[DEVCONF_RTR_PROBE_INTERVAL] =
5407 		jiffies_to_msecs(cnf->rtr_probe_interval);
5408 #ifdef CONFIG_IPV6_ROUTE_INFO
5409 	array[DEVCONF_ACCEPT_RA_RT_INFO_MIN_PLEN] = cnf->accept_ra_rt_info_min_plen;
5410 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
5411 #endif
5412 #endif
5413 	array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
5414 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
5415 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
5416 	array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
5417 	array[DEVCONF_USE_OPTIMISTIC] = cnf->use_optimistic;
5418 #endif
5419 #ifdef CONFIG_IPV6_MROUTE
5420 	array[DEVCONF_MC_FORWARDING] = cnf->mc_forwarding;
5421 #endif
5422 	array[DEVCONF_DISABLE_IPV6] = cnf->disable_ipv6;
5423 	array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad;
5424 	array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao;
5425 	array[DEVCONF_NDISC_NOTIFY] = cnf->ndisc_notify;
5426 	array[DEVCONF_SUPPRESS_FRAG_NDISC] = cnf->suppress_frag_ndisc;
5427 	array[DEVCONF_ACCEPT_RA_FROM_LOCAL] = cnf->accept_ra_from_local;
5428 	array[DEVCONF_ACCEPT_RA_MTU] = cnf->accept_ra_mtu;
5429 	array[DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN] = cnf->ignore_routes_with_linkdown;
5430 	/* we omit DEVCONF_STABLE_SECRET for now */
5431 	array[DEVCONF_USE_OIF_ADDRS_ONLY] = cnf->use_oif_addrs_only;
5432 	array[DEVCONF_DROP_UNICAST_IN_L2_MULTICAST] = cnf->drop_unicast_in_l2_multicast;
5433 	array[DEVCONF_DROP_UNSOLICITED_NA] = cnf->drop_unsolicited_na;
5434 	array[DEVCONF_KEEP_ADDR_ON_DOWN] = cnf->keep_addr_on_down;
5435 	array[DEVCONF_SEG6_ENABLED] = cnf->seg6_enabled;
5436 #ifdef CONFIG_IPV6_SEG6_HMAC
5437 	array[DEVCONF_SEG6_REQUIRE_HMAC] = cnf->seg6_require_hmac;
5438 #endif
5439 	array[DEVCONF_ENHANCED_DAD] = cnf->enhanced_dad;
5440 	array[DEVCONF_ADDR_GEN_MODE] = cnf->addr_gen_mode;
5441 	array[DEVCONF_DISABLE_POLICY] = cnf->disable_policy;
5442 	array[DEVCONF_NDISC_TCLASS] = cnf->ndisc_tclass;
5443 }
5444 
5445 static inline size_t inet6_ifla6_size(void)
5446 {
5447 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
5448 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
5449 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
5450 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
5451 	     + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
5452 	     + nla_total_size(sizeof(struct in6_addr)) /* IFLA_INET6_TOKEN */
5453 	     + nla_total_size(1) /* IFLA_INET6_ADDR_GEN_MODE */
5454 	     + 0;
5455 }
5456 
5457 static inline size_t inet6_if_nlmsg_size(void)
5458 {
5459 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
5460 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
5461 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
5462 	       + nla_total_size(4) /* IFLA_MTU */
5463 	       + nla_total_size(4) /* IFLA_LINK */
5464 	       + nla_total_size(1) /* IFLA_OPERSTATE */
5465 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
5466 }
5467 
5468 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
5469 					int bytes)
5470 {
5471 	int i;
5472 	int pad = bytes - sizeof(u64) * ICMP6_MIB_MAX;
5473 	BUG_ON(pad < 0);
5474 
5475 	/* Use put_unaligned() because stats may not be aligned for u64. */
5476 	put_unaligned(ICMP6_MIB_MAX, &stats[0]);
5477 	for (i = 1; i < ICMP6_MIB_MAX; i++)
5478 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
5479 
5480 	memset(&stats[ICMP6_MIB_MAX], 0, pad);
5481 }
5482 
5483 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu *mib,
5484 					int bytes, size_t syncpoff)
5485 {
5486 	int i, c;
5487 	u64 buff[IPSTATS_MIB_MAX];
5488 	int pad = bytes - sizeof(u64) * IPSTATS_MIB_MAX;
5489 
5490 	BUG_ON(pad < 0);
5491 
5492 	memset(buff, 0, sizeof(buff));
5493 	buff[0] = IPSTATS_MIB_MAX;
5494 
5495 	for_each_possible_cpu(c) {
5496 		for (i = 1; i < IPSTATS_MIB_MAX; i++)
5497 			buff[i] += snmp_get_cpu_field64(mib, c, i, syncpoff);
5498 	}
5499 
5500 	memcpy(stats, buff, IPSTATS_MIB_MAX * sizeof(u64));
5501 	memset(&stats[IPSTATS_MIB_MAX], 0, pad);
5502 }
5503 
5504 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
5505 			     int bytes)
5506 {
5507 	switch (attrtype) {
5508 	case IFLA_INET6_STATS:
5509 		__snmp6_fill_stats64(stats, idev->stats.ipv6, bytes,
5510 				     offsetof(struct ipstats_mib, syncp));
5511 		break;
5512 	case IFLA_INET6_ICMP6STATS:
5513 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, bytes);
5514 		break;
5515 	}
5516 }
5517 
5518 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev,
5519 				  u32 ext_filter_mask)
5520 {
5521 	struct nlattr *nla;
5522 	struct ifla_cacheinfo ci;
5523 
5524 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, idev->if_flags))
5525 		goto nla_put_failure;
5526 	ci.max_reasm_len = IPV6_MAXPLEN;
5527 	ci.tstamp = cstamp_delta(idev->tstamp);
5528 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
5529 	ci.retrans_time = jiffies_to_msecs(NEIGH_VAR(idev->nd_parms, RETRANS_TIME));
5530 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
5531 		goto nla_put_failure;
5532 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
5533 	if (!nla)
5534 		goto nla_put_failure;
5535 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
5536 
5537 	/* XXX - MC not implemented */
5538 
5539 	if (ext_filter_mask & RTEXT_FILTER_SKIP_STATS)
5540 		return 0;
5541 
5542 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
5543 	if (!nla)
5544 		goto nla_put_failure;
5545 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
5546 
5547 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
5548 	if (!nla)
5549 		goto nla_put_failure;
5550 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
5551 
5552 	nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
5553 	if (!nla)
5554 		goto nla_put_failure;
5555 	read_lock_bh(&idev->lock);
5556 	memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
5557 	read_unlock_bh(&idev->lock);
5558 
5559 	if (nla_put_u8(skb, IFLA_INET6_ADDR_GEN_MODE, idev->cnf.addr_gen_mode))
5560 		goto nla_put_failure;
5561 
5562 	return 0;
5563 
5564 nla_put_failure:
5565 	return -EMSGSIZE;
5566 }
5567 
5568 static size_t inet6_get_link_af_size(const struct net_device *dev,
5569 				     u32 ext_filter_mask)
5570 {
5571 	if (!__in6_dev_get(dev))
5572 		return 0;
5573 
5574 	return inet6_ifla6_size();
5575 }
5576 
5577 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev,
5578 			      u32 ext_filter_mask)
5579 {
5580 	struct inet6_dev *idev = __in6_dev_get(dev);
5581 
5582 	if (!idev)
5583 		return -ENODATA;
5584 
5585 	if (inet6_fill_ifla6_attrs(skb, idev, ext_filter_mask) < 0)
5586 		return -EMSGSIZE;
5587 
5588 	return 0;
5589 }
5590 
5591 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token)
5592 {
5593 	struct inet6_ifaddr *ifp;
5594 	struct net_device *dev = idev->dev;
5595 	bool clear_token, update_rs = false;
5596 	struct in6_addr ll_addr;
5597 
5598 	ASSERT_RTNL();
5599 
5600 	if (!token)
5601 		return -EINVAL;
5602 	if (dev->flags & (IFF_LOOPBACK | IFF_NOARP))
5603 		return -EINVAL;
5604 	if (!ipv6_accept_ra(idev))
5605 		return -EINVAL;
5606 	if (idev->cnf.rtr_solicits == 0)
5607 		return -EINVAL;
5608 
5609 	write_lock_bh(&idev->lock);
5610 
5611 	BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
5612 	memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
5613 
5614 	write_unlock_bh(&idev->lock);
5615 
5616 	clear_token = ipv6_addr_any(token);
5617 	if (clear_token)
5618 		goto update_lft;
5619 
5620 	if (!idev->dead && (idev->if_flags & IF_READY) &&
5621 	    !ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
5622 			     IFA_F_OPTIMISTIC)) {
5623 		/* If we're not ready, then normal ifup will take care
5624 		 * of this. Otherwise, we need to request our rs here.
5625 		 */
5626 		ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
5627 		update_rs = true;
5628 	}
5629 
5630 update_lft:
5631 	write_lock_bh(&idev->lock);
5632 
5633 	if (update_rs) {
5634 		idev->if_flags |= IF_RS_SENT;
5635 		idev->rs_interval = rfc3315_s14_backoff_init(
5636 			idev->cnf.rtr_solicit_interval);
5637 		idev->rs_probes = 1;
5638 		addrconf_mod_rs_timer(idev, idev->rs_interval);
5639 	}
5640 
5641 	/* Well, that's kinda nasty ... */
5642 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
5643 		spin_lock(&ifp->lock);
5644 		if (ifp->tokenized) {
5645 			ifp->valid_lft = 0;
5646 			ifp->prefered_lft = 0;
5647 		}
5648 		spin_unlock(&ifp->lock);
5649 	}
5650 
5651 	write_unlock_bh(&idev->lock);
5652 	inet6_ifinfo_notify(RTM_NEWLINK, idev);
5653 	addrconf_verify_rtnl();
5654 	return 0;
5655 }
5656 
5657 static const struct nla_policy inet6_af_policy[IFLA_INET6_MAX + 1] = {
5658 	[IFLA_INET6_ADDR_GEN_MODE]	= { .type = NLA_U8 },
5659 	[IFLA_INET6_TOKEN]		= { .len = sizeof(struct in6_addr) },
5660 };
5661 
5662 static int check_addr_gen_mode(int mode)
5663 {
5664 	if (mode != IN6_ADDR_GEN_MODE_EUI64 &&
5665 	    mode != IN6_ADDR_GEN_MODE_NONE &&
5666 	    mode != IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5667 	    mode != IN6_ADDR_GEN_MODE_RANDOM)
5668 		return -EINVAL;
5669 	return 1;
5670 }
5671 
5672 static int check_stable_privacy(struct inet6_dev *idev, struct net *net,
5673 				int mode)
5674 {
5675 	if (mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5676 	    !idev->cnf.stable_secret.initialized &&
5677 	    !net->ipv6.devconf_dflt->stable_secret.initialized)
5678 		return -EINVAL;
5679 	return 1;
5680 }
5681 
5682 static int inet6_validate_link_af(const struct net_device *dev,
5683 				  const struct nlattr *nla)
5684 {
5685 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5686 	struct inet6_dev *idev = NULL;
5687 	int err;
5688 
5689 	if (dev) {
5690 		idev = __in6_dev_get(dev);
5691 		if (!idev)
5692 			return -EAFNOSUPPORT;
5693 	}
5694 
5695 	err = nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla,
5696 					  inet6_af_policy, NULL);
5697 	if (err)
5698 		return err;
5699 
5700 	if (!tb[IFLA_INET6_TOKEN] && !tb[IFLA_INET6_ADDR_GEN_MODE])
5701 		return -EINVAL;
5702 
5703 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
5704 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
5705 
5706 		if (check_addr_gen_mode(mode) < 0)
5707 			return -EINVAL;
5708 		if (dev && check_stable_privacy(idev, dev_net(dev), mode) < 0)
5709 			return -EINVAL;
5710 	}
5711 
5712 	return 0;
5713 }
5714 
5715 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla)
5716 {
5717 	struct inet6_dev *idev = __in6_dev_get(dev);
5718 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5719 	int err;
5720 
5721 	if (!idev)
5722 		return -EAFNOSUPPORT;
5723 
5724 	if (nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla, NULL, NULL) < 0)
5725 		BUG();
5726 
5727 	if (tb[IFLA_INET6_TOKEN]) {
5728 		err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]));
5729 		if (err)
5730 			return err;
5731 	}
5732 
5733 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
5734 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
5735 
5736 		idev->cnf.addr_gen_mode = mode;
5737 	}
5738 
5739 	return 0;
5740 }
5741 
5742 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
5743 			     u32 portid, u32 seq, int event, unsigned int flags)
5744 {
5745 	struct net_device *dev = idev->dev;
5746 	struct ifinfomsg *hdr;
5747 	struct nlmsghdr *nlh;
5748 	void *protoinfo;
5749 
5750 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
5751 	if (!nlh)
5752 		return -EMSGSIZE;
5753 
5754 	hdr = nlmsg_data(nlh);
5755 	hdr->ifi_family = AF_INET6;
5756 	hdr->__ifi_pad = 0;
5757 	hdr->ifi_type = dev->type;
5758 	hdr->ifi_index = dev->ifindex;
5759 	hdr->ifi_flags = dev_get_flags(dev);
5760 	hdr->ifi_change = 0;
5761 
5762 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
5763 	    (dev->addr_len &&
5764 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
5765 	    nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
5766 	    (dev->ifindex != dev_get_iflink(dev) &&
5767 	     nla_put_u32(skb, IFLA_LINK, dev_get_iflink(dev))) ||
5768 	    nla_put_u8(skb, IFLA_OPERSTATE,
5769 		       netif_running(dev) ? dev->operstate : IF_OPER_DOWN))
5770 		goto nla_put_failure;
5771 	protoinfo = nla_nest_start_noflag(skb, IFLA_PROTINFO);
5772 	if (!protoinfo)
5773 		goto nla_put_failure;
5774 
5775 	if (inet6_fill_ifla6_attrs(skb, idev, 0) < 0)
5776 		goto nla_put_failure;
5777 
5778 	nla_nest_end(skb, protoinfo);
5779 	nlmsg_end(skb, nlh);
5780 	return 0;
5781 
5782 nla_put_failure:
5783 	nlmsg_cancel(skb, nlh);
5784 	return -EMSGSIZE;
5785 }
5786 
5787 static int inet6_valid_dump_ifinfo(const struct nlmsghdr *nlh,
5788 				   struct netlink_ext_ack *extack)
5789 {
5790 	struct ifinfomsg *ifm;
5791 
5792 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5793 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for link dump request");
5794 		return -EINVAL;
5795 	}
5796 
5797 	if (nlmsg_attrlen(nlh, sizeof(*ifm))) {
5798 		NL_SET_ERR_MSG_MOD(extack, "Invalid data after header");
5799 		return -EINVAL;
5800 	}
5801 
5802 	ifm = nlmsg_data(nlh);
5803 	if (ifm->__ifi_pad || ifm->ifi_type || ifm->ifi_flags ||
5804 	    ifm->ifi_change || ifm->ifi_index) {
5805 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for dump request");
5806 		return -EINVAL;
5807 	}
5808 
5809 	return 0;
5810 }
5811 
5812 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
5813 {
5814 	struct net *net = sock_net(skb->sk);
5815 	int h, s_h;
5816 	int idx = 0, s_idx;
5817 	struct net_device *dev;
5818 	struct inet6_dev *idev;
5819 	struct hlist_head *head;
5820 
5821 	/* only requests using strict checking can pass data to
5822 	 * influence the dump
5823 	 */
5824 	if (cb->strict_check) {
5825 		int err = inet6_valid_dump_ifinfo(cb->nlh, cb->extack);
5826 
5827 		if (err < 0)
5828 			return err;
5829 	}
5830 
5831 	s_h = cb->args[0];
5832 	s_idx = cb->args[1];
5833 
5834 	rcu_read_lock();
5835 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
5836 		idx = 0;
5837 		head = &net->dev_index_head[h];
5838 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
5839 			if (idx < s_idx)
5840 				goto cont;
5841 			idev = __in6_dev_get(dev);
5842 			if (!idev)
5843 				goto cont;
5844 			if (inet6_fill_ifinfo(skb, idev,
5845 					      NETLINK_CB(cb->skb).portid,
5846 					      cb->nlh->nlmsg_seq,
5847 					      RTM_NEWLINK, NLM_F_MULTI) < 0)
5848 				goto out;
5849 cont:
5850 			idx++;
5851 		}
5852 	}
5853 out:
5854 	rcu_read_unlock();
5855 	cb->args[1] = idx;
5856 	cb->args[0] = h;
5857 
5858 	return skb->len;
5859 }
5860 
5861 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
5862 {
5863 	struct sk_buff *skb;
5864 	struct net *net = dev_net(idev->dev);
5865 	int err = -ENOBUFS;
5866 
5867 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
5868 	if (!skb)
5869 		goto errout;
5870 
5871 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
5872 	if (err < 0) {
5873 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
5874 		WARN_ON(err == -EMSGSIZE);
5875 		kfree_skb(skb);
5876 		goto errout;
5877 	}
5878 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
5879 	return;
5880 errout:
5881 	if (err < 0)
5882 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
5883 }
5884 
5885 static inline size_t inet6_prefix_nlmsg_size(void)
5886 {
5887 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
5888 	       + nla_total_size(sizeof(struct in6_addr))
5889 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
5890 }
5891 
5892 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
5893 			     struct prefix_info *pinfo, u32 portid, u32 seq,
5894 			     int event, unsigned int flags)
5895 {
5896 	struct prefixmsg *pmsg;
5897 	struct nlmsghdr *nlh;
5898 	struct prefix_cacheinfo	ci;
5899 
5900 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
5901 	if (!nlh)
5902 		return -EMSGSIZE;
5903 
5904 	pmsg = nlmsg_data(nlh);
5905 	pmsg->prefix_family = AF_INET6;
5906 	pmsg->prefix_pad1 = 0;
5907 	pmsg->prefix_pad2 = 0;
5908 	pmsg->prefix_ifindex = idev->dev->ifindex;
5909 	pmsg->prefix_len = pinfo->prefix_len;
5910 	pmsg->prefix_type = pinfo->type;
5911 	pmsg->prefix_pad3 = 0;
5912 	pmsg->prefix_flags = 0;
5913 	if (pinfo->onlink)
5914 		pmsg->prefix_flags |= IF_PREFIX_ONLINK;
5915 	if (pinfo->autoconf)
5916 		pmsg->prefix_flags |= IF_PREFIX_AUTOCONF;
5917 
5918 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
5919 		goto nla_put_failure;
5920 	ci.preferred_time = ntohl(pinfo->prefered);
5921 	ci.valid_time = ntohl(pinfo->valid);
5922 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
5923 		goto nla_put_failure;
5924 	nlmsg_end(skb, nlh);
5925 	return 0;
5926 
5927 nla_put_failure:
5928 	nlmsg_cancel(skb, nlh);
5929 	return -EMSGSIZE;
5930 }
5931 
5932 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
5933 			 struct prefix_info *pinfo)
5934 {
5935 	struct sk_buff *skb;
5936 	struct net *net = dev_net(idev->dev);
5937 	int err = -ENOBUFS;
5938 
5939 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
5940 	if (!skb)
5941 		goto errout;
5942 
5943 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
5944 	if (err < 0) {
5945 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
5946 		WARN_ON(err == -EMSGSIZE);
5947 		kfree_skb(skb);
5948 		goto errout;
5949 	}
5950 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
5951 	return;
5952 errout:
5953 	if (err < 0)
5954 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
5955 }
5956 
5957 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
5958 {
5959 	struct net *net = dev_net(ifp->idev->dev);
5960 
5961 	if (event)
5962 		ASSERT_RTNL();
5963 
5964 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
5965 
5966 	switch (event) {
5967 	case RTM_NEWADDR:
5968 		/*
5969 		 * If the address was optimistic we inserted the route at the
5970 		 * start of our DAD process, so we don't need to do it again.
5971 		 * If the device was taken down in the middle of the DAD
5972 		 * cycle there is a race where we could get here without a
5973 		 * host route, so nothing to insert. That will be fixed when
5974 		 * the device is brought up.
5975 		 */
5976 		if (ifp->rt && !rcu_access_pointer(ifp->rt->fib6_node)) {
5977 			ip6_ins_rt(net, ifp->rt);
5978 		} else if (!ifp->rt && (ifp->idev->dev->flags & IFF_UP)) {
5979 			pr_warn("BUG: Address %pI6c on device %s is missing its host route.\n",
5980 				&ifp->addr, ifp->idev->dev->name);
5981 		}
5982 
5983 		if (ifp->idev->cnf.forwarding)
5984 			addrconf_join_anycast(ifp);
5985 		if (!ipv6_addr_any(&ifp->peer_addr))
5986 			addrconf_prefix_route(&ifp->peer_addr, 128, 0,
5987 					      ifp->idev->dev, 0, 0,
5988 					      GFP_ATOMIC);
5989 		break;
5990 	case RTM_DELADDR:
5991 		if (ifp->idev->cnf.forwarding)
5992 			addrconf_leave_anycast(ifp);
5993 		addrconf_leave_solict(ifp->idev, &ifp->addr);
5994 		if (!ipv6_addr_any(&ifp->peer_addr)) {
5995 			struct fib6_info *rt;
5996 
5997 			rt = addrconf_get_prefix_route(&ifp->peer_addr, 128,
5998 						       ifp->idev->dev, 0, 0,
5999 						       false);
6000 			if (rt)
6001 				ip6_del_rt(net, rt);
6002 		}
6003 		if (ifp->rt) {
6004 			ip6_del_rt(net, ifp->rt);
6005 			ifp->rt = NULL;
6006 		}
6007 		rt_genid_bump_ipv6(net);
6008 		break;
6009 	}
6010 	atomic_inc(&net->ipv6.dev_addr_genid);
6011 }
6012 
6013 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
6014 {
6015 	rcu_read_lock_bh();
6016 	if (likely(ifp->idev->dead == 0))
6017 		__ipv6_ifa_notify(event, ifp);
6018 	rcu_read_unlock_bh();
6019 }
6020 
6021 #ifdef CONFIG_SYSCTL
6022 
6023 static
6024 int addrconf_sysctl_forward(struct ctl_table *ctl, int write,
6025 			   void __user *buffer, size_t *lenp, loff_t *ppos)
6026 {
6027 	int *valp = ctl->data;
6028 	int val = *valp;
6029 	loff_t pos = *ppos;
6030 	struct ctl_table lctl;
6031 	int ret;
6032 
6033 	/*
6034 	 * ctl->data points to idev->cnf.forwarding, we should
6035 	 * not modify it until we get the rtnl lock.
6036 	 */
6037 	lctl = *ctl;
6038 	lctl.data = &val;
6039 
6040 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6041 
6042 	if (write)
6043 		ret = addrconf_fixup_forwarding(ctl, valp, val);
6044 	if (ret)
6045 		*ppos = pos;
6046 	return ret;
6047 }
6048 
6049 static
6050 int addrconf_sysctl_mtu(struct ctl_table *ctl, int write,
6051 			void __user *buffer, size_t *lenp, loff_t *ppos)
6052 {
6053 	struct inet6_dev *idev = ctl->extra1;
6054 	int min_mtu = IPV6_MIN_MTU;
6055 	struct ctl_table lctl;
6056 
6057 	lctl = *ctl;
6058 	lctl.extra1 = &min_mtu;
6059 	lctl.extra2 = idev ? &idev->dev->mtu : NULL;
6060 
6061 	return proc_dointvec_minmax(&lctl, write, buffer, lenp, ppos);
6062 }
6063 
6064 static void dev_disable_change(struct inet6_dev *idev)
6065 {
6066 	struct netdev_notifier_info info;
6067 
6068 	if (!idev || !idev->dev)
6069 		return;
6070 
6071 	netdev_notifier_info_init(&info, idev->dev);
6072 	if (idev->cnf.disable_ipv6)
6073 		addrconf_notify(NULL, NETDEV_DOWN, &info);
6074 	else
6075 		addrconf_notify(NULL, NETDEV_UP, &info);
6076 }
6077 
6078 static void addrconf_disable_change(struct net *net, __s32 newf)
6079 {
6080 	struct net_device *dev;
6081 	struct inet6_dev *idev;
6082 
6083 	for_each_netdev(net, dev) {
6084 		idev = __in6_dev_get(dev);
6085 		if (idev) {
6086 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
6087 			idev->cnf.disable_ipv6 = newf;
6088 			if (changed)
6089 				dev_disable_change(idev);
6090 		}
6091 	}
6092 }
6093 
6094 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
6095 {
6096 	struct net *net;
6097 	int old;
6098 
6099 	if (!rtnl_trylock())
6100 		return restart_syscall();
6101 
6102 	net = (struct net *)table->extra2;
6103 	old = *p;
6104 	*p = newf;
6105 
6106 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
6107 		rtnl_unlock();
6108 		return 0;
6109 	}
6110 
6111 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
6112 		net->ipv6.devconf_dflt->disable_ipv6 = newf;
6113 		addrconf_disable_change(net, newf);
6114 	} else if ((!newf) ^ (!old))
6115 		dev_disable_change((struct inet6_dev *)table->extra1);
6116 
6117 	rtnl_unlock();
6118 	return 0;
6119 }
6120 
6121 static
6122 int addrconf_sysctl_disable(struct ctl_table *ctl, int write,
6123 			    void __user *buffer, size_t *lenp, 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 	/*
6132 	 * ctl->data points to idev->cnf.disable_ipv6, we should
6133 	 * not modify it until we get the rtnl lock.
6134 	 */
6135 	lctl = *ctl;
6136 	lctl.data = &val;
6137 
6138 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6139 
6140 	if (write)
6141 		ret = addrconf_disable_ipv6(ctl, valp, val);
6142 	if (ret)
6143 		*ppos = pos;
6144 	return ret;
6145 }
6146 
6147 static
6148 int addrconf_sysctl_proxy_ndp(struct ctl_table *ctl, int write,
6149 			      void __user *buffer, size_t *lenp, loff_t *ppos)
6150 {
6151 	int *valp = ctl->data;
6152 	int ret;
6153 	int old, new;
6154 
6155 	old = *valp;
6156 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
6157 	new = *valp;
6158 
6159 	if (write && old != new) {
6160 		struct net *net = ctl->extra2;
6161 
6162 		if (!rtnl_trylock())
6163 			return restart_syscall();
6164 
6165 		if (valp == &net->ipv6.devconf_dflt->proxy_ndp)
6166 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6167 						     NETCONFA_PROXY_NEIGH,
6168 						     NETCONFA_IFINDEX_DEFAULT,
6169 						     net->ipv6.devconf_dflt);
6170 		else if (valp == &net->ipv6.devconf_all->proxy_ndp)
6171 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6172 						     NETCONFA_PROXY_NEIGH,
6173 						     NETCONFA_IFINDEX_ALL,
6174 						     net->ipv6.devconf_all);
6175 		else {
6176 			struct inet6_dev *idev = ctl->extra1;
6177 
6178 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6179 						     NETCONFA_PROXY_NEIGH,
6180 						     idev->dev->ifindex,
6181 						     &idev->cnf);
6182 		}
6183 		rtnl_unlock();
6184 	}
6185 
6186 	return ret;
6187 }
6188 
6189 static int addrconf_sysctl_addr_gen_mode(struct ctl_table *ctl, int write,
6190 					 void __user *buffer, size_t *lenp,
6191 					 loff_t *ppos)
6192 {
6193 	int ret = 0;
6194 	u32 new_val;
6195 	struct inet6_dev *idev = (struct inet6_dev *)ctl->extra1;
6196 	struct net *net = (struct net *)ctl->extra2;
6197 	struct ctl_table tmp = {
6198 		.data = &new_val,
6199 		.maxlen = sizeof(new_val),
6200 		.mode = ctl->mode,
6201 	};
6202 
6203 	if (!rtnl_trylock())
6204 		return restart_syscall();
6205 
6206 	new_val = *((u32 *)ctl->data);
6207 
6208 	ret = proc_douintvec(&tmp, write, buffer, lenp, ppos);
6209 	if (ret != 0)
6210 		goto out;
6211 
6212 	if (write) {
6213 		if (check_addr_gen_mode(new_val) < 0) {
6214 			ret = -EINVAL;
6215 			goto out;
6216 		}
6217 
6218 		if (idev) {
6219 			if (check_stable_privacy(idev, net, new_val) < 0) {
6220 				ret = -EINVAL;
6221 				goto out;
6222 			}
6223 
6224 			if (idev->cnf.addr_gen_mode != new_val) {
6225 				idev->cnf.addr_gen_mode = new_val;
6226 				addrconf_dev_config(idev->dev);
6227 			}
6228 		} else if (&net->ipv6.devconf_all->addr_gen_mode == ctl->data) {
6229 			struct net_device *dev;
6230 
6231 			net->ipv6.devconf_dflt->addr_gen_mode = new_val;
6232 			for_each_netdev(net, dev) {
6233 				idev = __in6_dev_get(dev);
6234 				if (idev &&
6235 				    idev->cnf.addr_gen_mode != new_val) {
6236 					idev->cnf.addr_gen_mode = new_val;
6237 					addrconf_dev_config(idev->dev);
6238 				}
6239 			}
6240 		}
6241 
6242 		*((u32 *)ctl->data) = new_val;
6243 	}
6244 
6245 out:
6246 	rtnl_unlock();
6247 
6248 	return ret;
6249 }
6250 
6251 static int addrconf_sysctl_stable_secret(struct ctl_table *ctl, int write,
6252 					 void __user *buffer, size_t *lenp,
6253 					 loff_t *ppos)
6254 {
6255 	int err;
6256 	struct in6_addr addr;
6257 	char str[IPV6_MAX_STRLEN];
6258 	struct ctl_table lctl = *ctl;
6259 	struct net *net = ctl->extra2;
6260 	struct ipv6_stable_secret *secret = ctl->data;
6261 
6262 	if (&net->ipv6.devconf_all->stable_secret == ctl->data)
6263 		return -EIO;
6264 
6265 	lctl.maxlen = IPV6_MAX_STRLEN;
6266 	lctl.data = str;
6267 
6268 	if (!rtnl_trylock())
6269 		return restart_syscall();
6270 
6271 	if (!write && !secret->initialized) {
6272 		err = -EIO;
6273 		goto out;
6274 	}
6275 
6276 	err = snprintf(str, sizeof(str), "%pI6", &secret->secret);
6277 	if (err >= sizeof(str)) {
6278 		err = -EIO;
6279 		goto out;
6280 	}
6281 
6282 	err = proc_dostring(&lctl, write, buffer, lenp, ppos);
6283 	if (err || !write)
6284 		goto out;
6285 
6286 	if (in6_pton(str, -1, addr.in6_u.u6_addr8, -1, NULL) != 1) {
6287 		err = -EIO;
6288 		goto out;
6289 	}
6290 
6291 	secret->initialized = true;
6292 	secret->secret = addr;
6293 
6294 	if (&net->ipv6.devconf_dflt->stable_secret == ctl->data) {
6295 		struct net_device *dev;
6296 
6297 		for_each_netdev(net, dev) {
6298 			struct inet6_dev *idev = __in6_dev_get(dev);
6299 
6300 			if (idev) {
6301 				idev->cnf.addr_gen_mode =
6302 					IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
6303 			}
6304 		}
6305 	} else {
6306 		struct inet6_dev *idev = ctl->extra1;
6307 
6308 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
6309 	}
6310 
6311 out:
6312 	rtnl_unlock();
6313 
6314 	return err;
6315 }
6316 
6317 static
6318 int addrconf_sysctl_ignore_routes_with_linkdown(struct ctl_table *ctl,
6319 						int write,
6320 						void __user *buffer,
6321 						size_t *lenp,
6322 						loff_t *ppos)
6323 {
6324 	int *valp = ctl->data;
6325 	int val = *valp;
6326 	loff_t pos = *ppos;
6327 	struct ctl_table lctl;
6328 	int ret;
6329 
6330 	/* ctl->data points to idev->cnf.ignore_routes_when_linkdown
6331 	 * we should not modify it until we get the rtnl lock.
6332 	 */
6333 	lctl = *ctl;
6334 	lctl.data = &val;
6335 
6336 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6337 
6338 	if (write)
6339 		ret = addrconf_fixup_linkdown(ctl, valp, val);
6340 	if (ret)
6341 		*ppos = pos;
6342 	return ret;
6343 }
6344 
6345 static
6346 void addrconf_set_nopolicy(struct rt6_info *rt, int action)
6347 {
6348 	if (rt) {
6349 		if (action)
6350 			rt->dst.flags |= DST_NOPOLICY;
6351 		else
6352 			rt->dst.flags &= ~DST_NOPOLICY;
6353 	}
6354 }
6355 
6356 static
6357 void addrconf_disable_policy_idev(struct inet6_dev *idev, int val)
6358 {
6359 	struct inet6_ifaddr *ifa;
6360 
6361 	read_lock_bh(&idev->lock);
6362 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
6363 		spin_lock(&ifa->lock);
6364 		if (ifa->rt) {
6365 			/* host routes only use builtin fib6_nh */
6366 			struct fib6_nh *nh = ifa->rt->fib6_nh;
6367 			int cpu;
6368 
6369 			rcu_read_lock();
6370 			ifa->rt->dst_nopolicy = val ? true : false;
6371 			if (nh->rt6i_pcpu) {
6372 				for_each_possible_cpu(cpu) {
6373 					struct rt6_info **rtp;
6374 
6375 					rtp = per_cpu_ptr(nh->rt6i_pcpu, cpu);
6376 					addrconf_set_nopolicy(*rtp, val);
6377 				}
6378 			}
6379 			rcu_read_unlock();
6380 		}
6381 		spin_unlock(&ifa->lock);
6382 	}
6383 	read_unlock_bh(&idev->lock);
6384 }
6385 
6386 static
6387 int addrconf_disable_policy(struct ctl_table *ctl, int *valp, int val)
6388 {
6389 	struct inet6_dev *idev;
6390 	struct net *net;
6391 
6392 	if (!rtnl_trylock())
6393 		return restart_syscall();
6394 
6395 	*valp = val;
6396 
6397 	net = (struct net *)ctl->extra2;
6398 	if (valp == &net->ipv6.devconf_dflt->disable_policy) {
6399 		rtnl_unlock();
6400 		return 0;
6401 	}
6402 
6403 	if (valp == &net->ipv6.devconf_all->disable_policy)  {
6404 		struct net_device *dev;
6405 
6406 		for_each_netdev(net, dev) {
6407 			idev = __in6_dev_get(dev);
6408 			if (idev)
6409 				addrconf_disable_policy_idev(idev, val);
6410 		}
6411 	} else {
6412 		idev = (struct inet6_dev *)ctl->extra1;
6413 		addrconf_disable_policy_idev(idev, val);
6414 	}
6415 
6416 	rtnl_unlock();
6417 	return 0;
6418 }
6419 
6420 static
6421 int addrconf_sysctl_disable_policy(struct ctl_table *ctl, int write,
6422 				   void __user *buffer, size_t *lenp,
6423 				   loff_t *ppos)
6424 {
6425 	int *valp = ctl->data;
6426 	int val = *valp;
6427 	loff_t pos = *ppos;
6428 	struct ctl_table lctl;
6429 	int ret;
6430 
6431 	lctl = *ctl;
6432 	lctl.data = &val;
6433 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6434 
6435 	if (write && (*valp != val))
6436 		ret = addrconf_disable_policy(ctl, valp, val);
6437 
6438 	if (ret)
6439 		*ppos = pos;
6440 
6441 	return ret;
6442 }
6443 
6444 static int minus_one = -1;
6445 static const int two_five_five = 255;
6446 
6447 static const struct ctl_table addrconf_sysctl[] = {
6448 	{
6449 		.procname	= "forwarding",
6450 		.data		= &ipv6_devconf.forwarding,
6451 		.maxlen		= sizeof(int),
6452 		.mode		= 0644,
6453 		.proc_handler	= addrconf_sysctl_forward,
6454 	},
6455 	{
6456 		.procname	= "hop_limit",
6457 		.data		= &ipv6_devconf.hop_limit,
6458 		.maxlen		= sizeof(int),
6459 		.mode		= 0644,
6460 		.proc_handler	= proc_dointvec_minmax,
6461 		.extra1		= (void *)SYSCTL_ONE,
6462 		.extra2		= (void *)&two_five_five,
6463 	},
6464 	{
6465 		.procname	= "mtu",
6466 		.data		= &ipv6_devconf.mtu6,
6467 		.maxlen		= sizeof(int),
6468 		.mode		= 0644,
6469 		.proc_handler	= addrconf_sysctl_mtu,
6470 	},
6471 	{
6472 		.procname	= "accept_ra",
6473 		.data		= &ipv6_devconf.accept_ra,
6474 		.maxlen		= sizeof(int),
6475 		.mode		= 0644,
6476 		.proc_handler	= proc_dointvec,
6477 	},
6478 	{
6479 		.procname	= "accept_redirects",
6480 		.data		= &ipv6_devconf.accept_redirects,
6481 		.maxlen		= sizeof(int),
6482 		.mode		= 0644,
6483 		.proc_handler	= proc_dointvec,
6484 	},
6485 	{
6486 		.procname	= "autoconf",
6487 		.data		= &ipv6_devconf.autoconf,
6488 		.maxlen		= sizeof(int),
6489 		.mode		= 0644,
6490 		.proc_handler	= proc_dointvec,
6491 	},
6492 	{
6493 		.procname	= "dad_transmits",
6494 		.data		= &ipv6_devconf.dad_transmits,
6495 		.maxlen		= sizeof(int),
6496 		.mode		= 0644,
6497 		.proc_handler	= proc_dointvec,
6498 	},
6499 	{
6500 		.procname	= "router_solicitations",
6501 		.data		= &ipv6_devconf.rtr_solicits,
6502 		.maxlen		= sizeof(int),
6503 		.mode		= 0644,
6504 		.proc_handler	= proc_dointvec_minmax,
6505 		.extra1		= &minus_one,
6506 	},
6507 	{
6508 		.procname	= "router_solicitation_interval",
6509 		.data		= &ipv6_devconf.rtr_solicit_interval,
6510 		.maxlen		= sizeof(int),
6511 		.mode		= 0644,
6512 		.proc_handler	= proc_dointvec_jiffies,
6513 	},
6514 	{
6515 		.procname	= "router_solicitation_max_interval",
6516 		.data		= &ipv6_devconf.rtr_solicit_max_interval,
6517 		.maxlen		= sizeof(int),
6518 		.mode		= 0644,
6519 		.proc_handler	= proc_dointvec_jiffies,
6520 	},
6521 	{
6522 		.procname	= "router_solicitation_delay",
6523 		.data		= &ipv6_devconf.rtr_solicit_delay,
6524 		.maxlen		= sizeof(int),
6525 		.mode		= 0644,
6526 		.proc_handler	= proc_dointvec_jiffies,
6527 	},
6528 	{
6529 		.procname	= "force_mld_version",
6530 		.data		= &ipv6_devconf.force_mld_version,
6531 		.maxlen		= sizeof(int),
6532 		.mode		= 0644,
6533 		.proc_handler	= proc_dointvec,
6534 	},
6535 	{
6536 		.procname	= "mldv1_unsolicited_report_interval",
6537 		.data		=
6538 			&ipv6_devconf.mldv1_unsolicited_report_interval,
6539 		.maxlen		= sizeof(int),
6540 		.mode		= 0644,
6541 		.proc_handler	= proc_dointvec_ms_jiffies,
6542 	},
6543 	{
6544 		.procname	= "mldv2_unsolicited_report_interval",
6545 		.data		=
6546 			&ipv6_devconf.mldv2_unsolicited_report_interval,
6547 		.maxlen		= sizeof(int),
6548 		.mode		= 0644,
6549 		.proc_handler	= proc_dointvec_ms_jiffies,
6550 	},
6551 	{
6552 		.procname	= "use_tempaddr",
6553 		.data		= &ipv6_devconf.use_tempaddr,
6554 		.maxlen		= sizeof(int),
6555 		.mode		= 0644,
6556 		.proc_handler	= proc_dointvec,
6557 	},
6558 	{
6559 		.procname	= "temp_valid_lft",
6560 		.data		= &ipv6_devconf.temp_valid_lft,
6561 		.maxlen		= sizeof(int),
6562 		.mode		= 0644,
6563 		.proc_handler	= proc_dointvec,
6564 	},
6565 	{
6566 		.procname	= "temp_prefered_lft",
6567 		.data		= &ipv6_devconf.temp_prefered_lft,
6568 		.maxlen		= sizeof(int),
6569 		.mode		= 0644,
6570 		.proc_handler	= proc_dointvec,
6571 	},
6572 	{
6573 		.procname	= "regen_max_retry",
6574 		.data		= &ipv6_devconf.regen_max_retry,
6575 		.maxlen		= sizeof(int),
6576 		.mode		= 0644,
6577 		.proc_handler	= proc_dointvec,
6578 	},
6579 	{
6580 		.procname	= "max_desync_factor",
6581 		.data		= &ipv6_devconf.max_desync_factor,
6582 		.maxlen		= sizeof(int),
6583 		.mode		= 0644,
6584 		.proc_handler	= proc_dointvec,
6585 	},
6586 	{
6587 		.procname	= "max_addresses",
6588 		.data		= &ipv6_devconf.max_addresses,
6589 		.maxlen		= sizeof(int),
6590 		.mode		= 0644,
6591 		.proc_handler	= proc_dointvec,
6592 	},
6593 	{
6594 		.procname	= "accept_ra_defrtr",
6595 		.data		= &ipv6_devconf.accept_ra_defrtr,
6596 		.maxlen		= sizeof(int),
6597 		.mode		= 0644,
6598 		.proc_handler	= proc_dointvec,
6599 	},
6600 	{
6601 		.procname	= "accept_ra_min_hop_limit",
6602 		.data		= &ipv6_devconf.accept_ra_min_hop_limit,
6603 		.maxlen		= sizeof(int),
6604 		.mode		= 0644,
6605 		.proc_handler	= proc_dointvec,
6606 	},
6607 	{
6608 		.procname	= "accept_ra_pinfo",
6609 		.data		= &ipv6_devconf.accept_ra_pinfo,
6610 		.maxlen		= sizeof(int),
6611 		.mode		= 0644,
6612 		.proc_handler	= proc_dointvec,
6613 	},
6614 #ifdef CONFIG_IPV6_ROUTER_PREF
6615 	{
6616 		.procname	= "accept_ra_rtr_pref",
6617 		.data		= &ipv6_devconf.accept_ra_rtr_pref,
6618 		.maxlen		= sizeof(int),
6619 		.mode		= 0644,
6620 		.proc_handler	= proc_dointvec,
6621 	},
6622 	{
6623 		.procname	= "router_probe_interval",
6624 		.data		= &ipv6_devconf.rtr_probe_interval,
6625 		.maxlen		= sizeof(int),
6626 		.mode		= 0644,
6627 		.proc_handler	= proc_dointvec_jiffies,
6628 	},
6629 #ifdef CONFIG_IPV6_ROUTE_INFO
6630 	{
6631 		.procname	= "accept_ra_rt_info_min_plen",
6632 		.data		= &ipv6_devconf.accept_ra_rt_info_min_plen,
6633 		.maxlen		= sizeof(int),
6634 		.mode		= 0644,
6635 		.proc_handler	= proc_dointvec,
6636 	},
6637 	{
6638 		.procname	= "accept_ra_rt_info_max_plen",
6639 		.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
6640 		.maxlen		= sizeof(int),
6641 		.mode		= 0644,
6642 		.proc_handler	= proc_dointvec,
6643 	},
6644 #endif
6645 #endif
6646 	{
6647 		.procname	= "proxy_ndp",
6648 		.data		= &ipv6_devconf.proxy_ndp,
6649 		.maxlen		= sizeof(int),
6650 		.mode		= 0644,
6651 		.proc_handler	= addrconf_sysctl_proxy_ndp,
6652 	},
6653 	{
6654 		.procname	= "accept_source_route",
6655 		.data		= &ipv6_devconf.accept_source_route,
6656 		.maxlen		= sizeof(int),
6657 		.mode		= 0644,
6658 		.proc_handler	= proc_dointvec,
6659 	},
6660 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
6661 	{
6662 		.procname	= "optimistic_dad",
6663 		.data		= &ipv6_devconf.optimistic_dad,
6664 		.maxlen		= sizeof(int),
6665 		.mode		= 0644,
6666 		.proc_handler   = proc_dointvec,
6667 	},
6668 	{
6669 		.procname	= "use_optimistic",
6670 		.data		= &ipv6_devconf.use_optimistic,
6671 		.maxlen		= sizeof(int),
6672 		.mode		= 0644,
6673 		.proc_handler	= proc_dointvec,
6674 	},
6675 #endif
6676 #ifdef CONFIG_IPV6_MROUTE
6677 	{
6678 		.procname	= "mc_forwarding",
6679 		.data		= &ipv6_devconf.mc_forwarding,
6680 		.maxlen		= sizeof(int),
6681 		.mode		= 0444,
6682 		.proc_handler	= proc_dointvec,
6683 	},
6684 #endif
6685 	{
6686 		.procname	= "disable_ipv6",
6687 		.data		= &ipv6_devconf.disable_ipv6,
6688 		.maxlen		= sizeof(int),
6689 		.mode		= 0644,
6690 		.proc_handler	= addrconf_sysctl_disable,
6691 	},
6692 	{
6693 		.procname	= "accept_dad",
6694 		.data		= &ipv6_devconf.accept_dad,
6695 		.maxlen		= sizeof(int),
6696 		.mode		= 0644,
6697 		.proc_handler	= proc_dointvec,
6698 	},
6699 	{
6700 		.procname	= "force_tllao",
6701 		.data		= &ipv6_devconf.force_tllao,
6702 		.maxlen		= sizeof(int),
6703 		.mode		= 0644,
6704 		.proc_handler	= proc_dointvec
6705 	},
6706 	{
6707 		.procname	= "ndisc_notify",
6708 		.data		= &ipv6_devconf.ndisc_notify,
6709 		.maxlen		= sizeof(int),
6710 		.mode		= 0644,
6711 		.proc_handler	= proc_dointvec
6712 	},
6713 	{
6714 		.procname	= "suppress_frag_ndisc",
6715 		.data		= &ipv6_devconf.suppress_frag_ndisc,
6716 		.maxlen		= sizeof(int),
6717 		.mode		= 0644,
6718 		.proc_handler	= proc_dointvec
6719 	},
6720 	{
6721 		.procname	= "accept_ra_from_local",
6722 		.data		= &ipv6_devconf.accept_ra_from_local,
6723 		.maxlen		= sizeof(int),
6724 		.mode		= 0644,
6725 		.proc_handler	= proc_dointvec,
6726 	},
6727 	{
6728 		.procname	= "accept_ra_mtu",
6729 		.data		= &ipv6_devconf.accept_ra_mtu,
6730 		.maxlen		= sizeof(int),
6731 		.mode		= 0644,
6732 		.proc_handler	= proc_dointvec,
6733 	},
6734 	{
6735 		.procname	= "stable_secret",
6736 		.data		= &ipv6_devconf.stable_secret,
6737 		.maxlen		= IPV6_MAX_STRLEN,
6738 		.mode		= 0600,
6739 		.proc_handler	= addrconf_sysctl_stable_secret,
6740 	},
6741 	{
6742 		.procname	= "use_oif_addrs_only",
6743 		.data		= &ipv6_devconf.use_oif_addrs_only,
6744 		.maxlen		= sizeof(int),
6745 		.mode		= 0644,
6746 		.proc_handler	= proc_dointvec,
6747 	},
6748 	{
6749 		.procname	= "ignore_routes_with_linkdown",
6750 		.data		= &ipv6_devconf.ignore_routes_with_linkdown,
6751 		.maxlen		= sizeof(int),
6752 		.mode		= 0644,
6753 		.proc_handler	= addrconf_sysctl_ignore_routes_with_linkdown,
6754 	},
6755 	{
6756 		.procname	= "drop_unicast_in_l2_multicast",
6757 		.data		= &ipv6_devconf.drop_unicast_in_l2_multicast,
6758 		.maxlen		= sizeof(int),
6759 		.mode		= 0644,
6760 		.proc_handler	= proc_dointvec,
6761 	},
6762 	{
6763 		.procname	= "drop_unsolicited_na",
6764 		.data		= &ipv6_devconf.drop_unsolicited_na,
6765 		.maxlen		= sizeof(int),
6766 		.mode		= 0644,
6767 		.proc_handler	= proc_dointvec,
6768 	},
6769 	{
6770 		.procname	= "keep_addr_on_down",
6771 		.data		= &ipv6_devconf.keep_addr_on_down,
6772 		.maxlen		= sizeof(int),
6773 		.mode		= 0644,
6774 		.proc_handler	= proc_dointvec,
6775 
6776 	},
6777 	{
6778 		.procname	= "seg6_enabled",
6779 		.data		= &ipv6_devconf.seg6_enabled,
6780 		.maxlen		= sizeof(int),
6781 		.mode		= 0644,
6782 		.proc_handler	= proc_dointvec,
6783 	},
6784 #ifdef CONFIG_IPV6_SEG6_HMAC
6785 	{
6786 		.procname	= "seg6_require_hmac",
6787 		.data		= &ipv6_devconf.seg6_require_hmac,
6788 		.maxlen		= sizeof(int),
6789 		.mode		= 0644,
6790 		.proc_handler	= proc_dointvec,
6791 	},
6792 #endif
6793 	{
6794 		.procname       = "enhanced_dad",
6795 		.data           = &ipv6_devconf.enhanced_dad,
6796 		.maxlen         = sizeof(int),
6797 		.mode           = 0644,
6798 		.proc_handler   = proc_dointvec,
6799 	},
6800 	{
6801 		.procname		= "addr_gen_mode",
6802 		.data			= &ipv6_devconf.addr_gen_mode,
6803 		.maxlen			= sizeof(int),
6804 		.mode			= 0644,
6805 		.proc_handler	= addrconf_sysctl_addr_gen_mode,
6806 	},
6807 	{
6808 		.procname       = "disable_policy",
6809 		.data           = &ipv6_devconf.disable_policy,
6810 		.maxlen         = sizeof(int),
6811 		.mode           = 0644,
6812 		.proc_handler   = addrconf_sysctl_disable_policy,
6813 	},
6814 	{
6815 		.procname	= "ndisc_tclass",
6816 		.data		= &ipv6_devconf.ndisc_tclass,
6817 		.maxlen		= sizeof(int),
6818 		.mode		= 0644,
6819 		.proc_handler	= proc_dointvec_minmax,
6820 		.extra1		= (void *)SYSCTL_ZERO,
6821 		.extra2		= (void *)&two_five_five,
6822 	},
6823 	{
6824 		/* sentinel */
6825 	}
6826 };
6827 
6828 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
6829 		struct inet6_dev *idev, struct ipv6_devconf *p)
6830 {
6831 	int i, ifindex;
6832 	struct ctl_table *table;
6833 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
6834 
6835 	table = kmemdup(addrconf_sysctl, sizeof(addrconf_sysctl), GFP_KERNEL);
6836 	if (!table)
6837 		goto out;
6838 
6839 	for (i = 0; table[i].data; i++) {
6840 		table[i].data += (char *)p - (char *)&ipv6_devconf;
6841 		/* If one of these is already set, then it is not safe to
6842 		 * overwrite either of them: this makes proc_dointvec_minmax
6843 		 * usable.
6844 		 */
6845 		if (!table[i].extra1 && !table[i].extra2) {
6846 			table[i].extra1 = idev; /* embedded; no ref */
6847 			table[i].extra2 = net;
6848 		}
6849 	}
6850 
6851 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
6852 
6853 	p->sysctl_header = register_net_sysctl(net, path, table);
6854 	if (!p->sysctl_header)
6855 		goto free;
6856 
6857 	if (!strcmp(dev_name, "all"))
6858 		ifindex = NETCONFA_IFINDEX_ALL;
6859 	else if (!strcmp(dev_name, "default"))
6860 		ifindex = NETCONFA_IFINDEX_DEFAULT;
6861 	else
6862 		ifindex = idev->dev->ifindex;
6863 	inet6_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL,
6864 				     ifindex, p);
6865 	return 0;
6866 
6867 free:
6868 	kfree(table);
6869 out:
6870 	return -ENOBUFS;
6871 }
6872 
6873 static void __addrconf_sysctl_unregister(struct net *net,
6874 					 struct ipv6_devconf *p, int ifindex)
6875 {
6876 	struct ctl_table *table;
6877 
6878 	if (!p->sysctl_header)
6879 		return;
6880 
6881 	table = p->sysctl_header->ctl_table_arg;
6882 	unregister_net_sysctl_table(p->sysctl_header);
6883 	p->sysctl_header = NULL;
6884 	kfree(table);
6885 
6886 	inet6_netconf_notify_devconf(net, RTM_DELNETCONF, 0, ifindex, NULL);
6887 }
6888 
6889 static int addrconf_sysctl_register(struct inet6_dev *idev)
6890 {
6891 	int err;
6892 
6893 	if (!sysctl_dev_name_is_allowed(idev->dev->name))
6894 		return -EINVAL;
6895 
6896 	err = neigh_sysctl_register(idev->dev, idev->nd_parms,
6897 				    &ndisc_ifinfo_sysctl_change);
6898 	if (err)
6899 		return err;
6900 	err = __addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
6901 					 idev, &idev->cnf);
6902 	if (err)
6903 		neigh_sysctl_unregister(idev->nd_parms);
6904 
6905 	return err;
6906 }
6907 
6908 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
6909 {
6910 	__addrconf_sysctl_unregister(dev_net(idev->dev), &idev->cnf,
6911 				     idev->dev->ifindex);
6912 	neigh_sysctl_unregister(idev->nd_parms);
6913 }
6914 
6915 
6916 #endif
6917 
6918 static int __net_init addrconf_init_net(struct net *net)
6919 {
6920 	int err = -ENOMEM;
6921 	struct ipv6_devconf *all, *dflt;
6922 
6923 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
6924 	if (!all)
6925 		goto err_alloc_all;
6926 
6927 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
6928 	if (!dflt)
6929 		goto err_alloc_dflt;
6930 
6931 	if (IS_ENABLED(CONFIG_SYSCTL) &&
6932 	    sysctl_devconf_inherit_init_net == 1 && !net_eq(net, &init_net)) {
6933 		memcpy(all, init_net.ipv6.devconf_all, sizeof(ipv6_devconf));
6934 		memcpy(dflt, init_net.ipv6.devconf_dflt, sizeof(ipv6_devconf_dflt));
6935 	}
6936 
6937 	/* these will be inherited by all namespaces */
6938 	dflt->autoconf = ipv6_defaults.autoconf;
6939 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
6940 
6941 	dflt->stable_secret.initialized = false;
6942 	all->stable_secret.initialized = false;
6943 
6944 	net->ipv6.devconf_all = all;
6945 	net->ipv6.devconf_dflt = dflt;
6946 
6947 #ifdef CONFIG_SYSCTL
6948 	err = __addrconf_sysctl_register(net, "all", NULL, all);
6949 	if (err < 0)
6950 		goto err_reg_all;
6951 
6952 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
6953 	if (err < 0)
6954 		goto err_reg_dflt;
6955 #endif
6956 	return 0;
6957 
6958 #ifdef CONFIG_SYSCTL
6959 err_reg_dflt:
6960 	__addrconf_sysctl_unregister(net, all, NETCONFA_IFINDEX_ALL);
6961 err_reg_all:
6962 	kfree(dflt);
6963 #endif
6964 err_alloc_dflt:
6965 	kfree(all);
6966 err_alloc_all:
6967 	return err;
6968 }
6969 
6970 static void __net_exit addrconf_exit_net(struct net *net)
6971 {
6972 #ifdef CONFIG_SYSCTL
6973 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_dflt,
6974 				     NETCONFA_IFINDEX_DEFAULT);
6975 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_all,
6976 				     NETCONFA_IFINDEX_ALL);
6977 #endif
6978 	kfree(net->ipv6.devconf_dflt);
6979 	kfree(net->ipv6.devconf_all);
6980 }
6981 
6982 static struct pernet_operations addrconf_ops = {
6983 	.init = addrconf_init_net,
6984 	.exit = addrconf_exit_net,
6985 };
6986 
6987 static struct rtnl_af_ops inet6_ops __read_mostly = {
6988 	.family		  = AF_INET6,
6989 	.fill_link_af	  = inet6_fill_link_af,
6990 	.get_link_af_size = inet6_get_link_af_size,
6991 	.validate_link_af = inet6_validate_link_af,
6992 	.set_link_af	  = inet6_set_link_af,
6993 };
6994 
6995 /*
6996  *	Init / cleanup code
6997  */
6998 
6999 int __init addrconf_init(void)
7000 {
7001 	struct inet6_dev *idev;
7002 	int i, err;
7003 
7004 	err = ipv6_addr_label_init();
7005 	if (err < 0) {
7006 		pr_crit("%s: cannot initialize default policy table: %d\n",
7007 			__func__, err);
7008 		goto out;
7009 	}
7010 
7011 	err = register_pernet_subsys(&addrconf_ops);
7012 	if (err < 0)
7013 		goto out_addrlabel;
7014 
7015 	addrconf_wq = create_workqueue("ipv6_addrconf");
7016 	if (!addrconf_wq) {
7017 		err = -ENOMEM;
7018 		goto out_nowq;
7019 	}
7020 
7021 	/* The addrconf netdev notifier requires that loopback_dev
7022 	 * has it's ipv6 private information allocated and setup
7023 	 * before it can bring up and give link-local addresses
7024 	 * to other devices which are up.
7025 	 *
7026 	 * Unfortunately, loopback_dev is not necessarily the first
7027 	 * entry in the global dev_base list of net devices.  In fact,
7028 	 * it is likely to be the very last entry on that list.
7029 	 * So this causes the notifier registry below to try and
7030 	 * give link-local addresses to all devices besides loopback_dev
7031 	 * first, then loopback_dev, which cases all the non-loopback_dev
7032 	 * devices to fail to get a link-local address.
7033 	 *
7034 	 * So, as a temporary fix, allocate the ipv6 structure for
7035 	 * loopback_dev first by hand.
7036 	 * Longer term, all of the dependencies ipv6 has upon the loopback
7037 	 * device and it being up should be removed.
7038 	 */
7039 	rtnl_lock();
7040 	idev = ipv6_add_dev(init_net.loopback_dev);
7041 	rtnl_unlock();
7042 	if (IS_ERR(idev)) {
7043 		err = PTR_ERR(idev);
7044 		goto errlo;
7045 	}
7046 
7047 	ip6_route_init_special_entries();
7048 
7049 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
7050 		INIT_HLIST_HEAD(&inet6_addr_lst[i]);
7051 
7052 	register_netdevice_notifier(&ipv6_dev_notf);
7053 
7054 	addrconf_verify();
7055 
7056 	rtnl_af_register(&inet6_ops);
7057 
7058 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETLINK,
7059 				   NULL, inet6_dump_ifinfo, 0);
7060 	if (err < 0)
7061 		goto errout;
7062 
7063 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_NEWADDR,
7064 				   inet6_rtm_newaddr, NULL, 0);
7065 	if (err < 0)
7066 		goto errout;
7067 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_DELADDR,
7068 				   inet6_rtm_deladdr, NULL, 0);
7069 	if (err < 0)
7070 		goto errout;
7071 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETADDR,
7072 				   inet6_rtm_getaddr, inet6_dump_ifaddr,
7073 				   RTNL_FLAG_DOIT_UNLOCKED);
7074 	if (err < 0)
7075 		goto errout;
7076 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETMULTICAST,
7077 				   NULL, inet6_dump_ifmcaddr, 0);
7078 	if (err < 0)
7079 		goto errout;
7080 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETANYCAST,
7081 				   NULL, inet6_dump_ifacaddr, 0);
7082 	if (err < 0)
7083 		goto errout;
7084 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETNETCONF,
7085 				   inet6_netconf_get_devconf,
7086 				   inet6_netconf_dump_devconf,
7087 				   RTNL_FLAG_DOIT_UNLOCKED);
7088 	if (err < 0)
7089 		goto errout;
7090 	err = ipv6_addr_label_rtnl_register();
7091 	if (err < 0)
7092 		goto errout;
7093 
7094 	return 0;
7095 errout:
7096 	rtnl_unregister_all(PF_INET6);
7097 	rtnl_af_unregister(&inet6_ops);
7098 	unregister_netdevice_notifier(&ipv6_dev_notf);
7099 errlo:
7100 	destroy_workqueue(addrconf_wq);
7101 out_nowq:
7102 	unregister_pernet_subsys(&addrconf_ops);
7103 out_addrlabel:
7104 	ipv6_addr_label_cleanup();
7105 out:
7106 	return err;
7107 }
7108 
7109 void addrconf_cleanup(void)
7110 {
7111 	struct net_device *dev;
7112 	int i;
7113 
7114 	unregister_netdevice_notifier(&ipv6_dev_notf);
7115 	unregister_pernet_subsys(&addrconf_ops);
7116 	ipv6_addr_label_cleanup();
7117 
7118 	rtnl_af_unregister(&inet6_ops);
7119 
7120 	rtnl_lock();
7121 
7122 	/* clean dev list */
7123 	for_each_netdev(&init_net, dev) {
7124 		if (__in6_dev_get(dev) == NULL)
7125 			continue;
7126 		addrconf_ifdown(dev, 1);
7127 	}
7128 	addrconf_ifdown(init_net.loopback_dev, 2);
7129 
7130 	/*
7131 	 *	Check hash table.
7132 	 */
7133 	spin_lock_bh(&addrconf_hash_lock);
7134 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
7135 		WARN_ON(!hlist_empty(&inet6_addr_lst[i]));
7136 	spin_unlock_bh(&addrconf_hash_lock);
7137 	cancel_delayed_work(&addr_chk_work);
7138 	rtnl_unlock();
7139 
7140 	destroy_workqueue(addrconf_wq);
7141 }
7142