xref: /openbmc/linux/net/ipv6/addrconf.c (revision 8e8e676d0b3c7f074c719c7c05b20296b9b0b0b1)
1 /*
2  *	IPv6 Address [auto]configuration
3  *	Linux INET6 implementation
4  *
5  *	Authors:
6  *	Pedro Roque		<roque@di.fc.ul.pt>
7  *	Alexey Kuznetsov	<kuznet@ms2.inr.ac.ru>
8  *
9  *	This program is free software; you can redistribute it and/or
10  *      modify it under the terms of the GNU General Public License
11  *      as published by the Free Software Foundation; either version
12  *      2 of the License, or (at your option) any later version.
13  */
14 
15 /*
16  *	Changes:
17  *
18  *	Janos Farkas			:	delete timer on ifdown
19  *	<chexum@bankinf.banki.hu>
20  *	Andi Kleen			:	kill double kfree on module
21  *						unload.
22  *	Maciej W. Rozycki		:	FDDI support
23  *	sekiya@USAGI			:	Don't send too many RS
24  *						packets.
25  *	yoshfuji@USAGI			:       Fixed interval between DAD
26  *						packets.
27  *	YOSHIFUJI Hideaki @USAGI	:	improved accuracy of
28  *						address validation timer.
29  *	YOSHIFUJI Hideaki @USAGI	:	Privacy Extensions (RFC3041)
30  *						support.
31  *	Yuji SEKIYA @USAGI		:	Don't assign a same IPv6
32  *						address on a same interface.
33  *	YOSHIFUJI Hideaki @USAGI	:	ARCnet support
34  *	YOSHIFUJI Hideaki @USAGI	:	convert /proc/net/if_inet6 to
35  *						seq_file.
36  *	YOSHIFUJI Hideaki @USAGI	:	improved source address
37  *						selection; consider scope,
38  *						status etc.
39  */
40 
41 #define pr_fmt(fmt) "IPv6: " fmt
42 
43 #include <linux/errno.h>
44 #include <linux/types.h>
45 #include <linux/kernel.h>
46 #include <linux/socket.h>
47 #include <linux/sockios.h>
48 #include <linux/net.h>
49 #include <linux/inet.h>
50 #include <linux/in6.h>
51 #include <linux/netdevice.h>
52 #include <linux/if_addr.h>
53 #include <linux/if_arp.h>
54 #include <linux/if_arcnet.h>
55 #include <linux/if_infiniband.h>
56 #include <linux/route.h>
57 #include <linux/inetdevice.h>
58 #include <linux/init.h>
59 #include <linux/slab.h>
60 #ifdef CONFIG_SYSCTL
61 #include <linux/sysctl.h>
62 #endif
63 #include <linux/capability.h>
64 #include <linux/delay.h>
65 #include <linux/notifier.h>
66 #include <linux/string.h>
67 #include <linux/hash.h>
68 
69 #include <net/net_namespace.h>
70 #include <net/sock.h>
71 #include <net/snmp.h>
72 
73 #include <net/af_ieee802154.h>
74 #include <net/firewire.h>
75 #include <net/ipv6.h>
76 #include <net/protocol.h>
77 #include <net/ndisc.h>
78 #include <net/ip6_route.h>
79 #include <net/addrconf.h>
80 #include <net/tcp.h>
81 #include <net/ip.h>
82 #include <net/netlink.h>
83 #include <net/pkt_sched.h>
84 #include <linux/if_tunnel.h>
85 #include <linux/rtnetlink.h>
86 #include <linux/netconf.h>
87 #include <linux/random.h>
88 #include <linux/uaccess.h>
89 #include <asm/unaligned.h>
90 
91 #include <linux/proc_fs.h>
92 #include <linux/seq_file.h>
93 #include <linux/export.h>
94 
95 /* Set to 3 to get tracing... */
96 #define ACONF_DEBUG 2
97 
98 #if ACONF_DEBUG >= 3
99 #define ADBG(fmt, ...) printk(fmt, ##__VA_ARGS__)
100 #else
101 #define ADBG(fmt, ...) do { if (0) printk(fmt, ##__VA_ARGS__); } while (0)
102 #endif
103 
104 #define	INFINITY_LIFE_TIME	0xFFFFFFFF
105 
106 #define IPV6_MAX_STRLEN \
107 	sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255")
108 
109 static inline u32 cstamp_delta(unsigned long cstamp)
110 {
111 	return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
112 }
113 
114 #ifdef CONFIG_SYSCTL
115 static int addrconf_sysctl_register(struct inet6_dev *idev);
116 static void addrconf_sysctl_unregister(struct inet6_dev *idev);
117 #else
118 static inline int addrconf_sysctl_register(struct inet6_dev *idev)
119 {
120 	return 0;
121 }
122 
123 static inline void addrconf_sysctl_unregister(struct inet6_dev *idev)
124 {
125 }
126 #endif
127 
128 static void __ipv6_regen_rndid(struct inet6_dev *idev);
129 static void __ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr);
130 static void ipv6_regen_rndid(unsigned long data);
131 
132 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev);
133 static int ipv6_count_addresses(struct inet6_dev *idev);
134 static int ipv6_generate_stable_address(struct in6_addr *addr,
135 					u8 dad_count,
136 					const struct inet6_dev *idev);
137 
138 /*
139  *	Configured unicast address hash table
140  */
141 static struct hlist_head inet6_addr_lst[IN6_ADDR_HSIZE];
142 static DEFINE_SPINLOCK(addrconf_hash_lock);
143 
144 static void addrconf_verify(void);
145 static void addrconf_verify_rtnl(void);
146 static void addrconf_verify_work(struct work_struct *);
147 
148 static struct workqueue_struct *addrconf_wq;
149 static DECLARE_DELAYED_WORK(addr_chk_work, addrconf_verify_work);
150 
151 static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
152 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
153 
154 static void addrconf_type_change(struct net_device *dev,
155 				 unsigned long event);
156 static int addrconf_ifdown(struct net_device *dev, int how);
157 
158 static struct rt6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
159 						  int plen,
160 						  const struct net_device *dev,
161 						  u32 flags, u32 noflags);
162 
163 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
164 static void addrconf_dad_work(struct work_struct *w);
165 static void addrconf_dad_completed(struct inet6_ifaddr *ifp);
166 static void addrconf_dad_run(struct inet6_dev *idev);
167 static void addrconf_rs_timer(unsigned long data);
168 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
169 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
170 
171 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
172 				struct prefix_info *pinfo);
173 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
174 			       struct net_device *dev);
175 
176 static struct ipv6_devconf ipv6_devconf __read_mostly = {
177 	.forwarding		= 0,
178 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
179 	.mtu6			= IPV6_MIN_MTU,
180 	.accept_ra		= 1,
181 	.accept_redirects	= 1,
182 	.autoconf		= 1,
183 	.force_mld_version	= 0,
184 	.mldv1_unsolicited_report_interval = 10 * HZ,
185 	.mldv2_unsolicited_report_interval = HZ,
186 	.dad_transmits		= 1,
187 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
188 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
189 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
190 	.use_tempaddr		= 0,
191 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
192 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
193 	.regen_max_retry	= REGEN_MAX_RETRY,
194 	.max_desync_factor	= MAX_DESYNC_FACTOR,
195 	.max_addresses		= IPV6_MAX_ADDRESSES,
196 	.accept_ra_defrtr	= 1,
197 	.accept_ra_from_local	= 0,
198 	.accept_ra_pinfo	= 1,
199 #ifdef CONFIG_IPV6_ROUTER_PREF
200 	.accept_ra_rtr_pref	= 1,
201 	.rtr_probe_interval	= 60 * HZ,
202 #ifdef CONFIG_IPV6_ROUTE_INFO
203 	.accept_ra_rt_info_max_plen = 0,
204 #endif
205 #endif
206 	.proxy_ndp		= 0,
207 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
208 	.disable_ipv6		= 0,
209 	.accept_dad		= 1,
210 	.suppress_frag_ndisc	= 1,
211 	.accept_ra_mtu		= 1,
212 	.stable_secret		= {
213 		.initialized = false,
214 	}
215 };
216 
217 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
218 	.forwarding		= 0,
219 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
220 	.mtu6			= IPV6_MIN_MTU,
221 	.accept_ra		= 1,
222 	.accept_redirects	= 1,
223 	.autoconf		= 1,
224 	.force_mld_version	= 0,
225 	.mldv1_unsolicited_report_interval = 10 * HZ,
226 	.mldv2_unsolicited_report_interval = HZ,
227 	.dad_transmits		= 1,
228 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
229 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
230 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
231 	.use_tempaddr		= 0,
232 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
233 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
234 	.regen_max_retry	= REGEN_MAX_RETRY,
235 	.max_desync_factor	= MAX_DESYNC_FACTOR,
236 	.max_addresses		= IPV6_MAX_ADDRESSES,
237 	.accept_ra_defrtr	= 1,
238 	.accept_ra_from_local	= 0,
239 	.accept_ra_pinfo	= 1,
240 #ifdef CONFIG_IPV6_ROUTER_PREF
241 	.accept_ra_rtr_pref	= 1,
242 	.rtr_probe_interval	= 60 * HZ,
243 #ifdef CONFIG_IPV6_ROUTE_INFO
244 	.accept_ra_rt_info_max_plen = 0,
245 #endif
246 #endif
247 	.proxy_ndp		= 0,
248 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
249 	.disable_ipv6		= 0,
250 	.accept_dad		= 1,
251 	.suppress_frag_ndisc	= 1,
252 	.accept_ra_mtu		= 1,
253 	.stable_secret		= {
254 		.initialized = false,
255 	},
256 };
257 
258 /* Check if a valid qdisc is available */
259 static inline bool addrconf_qdisc_ok(const struct net_device *dev)
260 {
261 	return !qdisc_tx_is_noop(dev);
262 }
263 
264 static void addrconf_del_rs_timer(struct inet6_dev *idev)
265 {
266 	if (del_timer(&idev->rs_timer))
267 		__in6_dev_put(idev);
268 }
269 
270 static void addrconf_del_dad_work(struct inet6_ifaddr *ifp)
271 {
272 	if (cancel_delayed_work(&ifp->dad_work))
273 		__in6_ifa_put(ifp);
274 }
275 
276 static void addrconf_mod_rs_timer(struct inet6_dev *idev,
277 				  unsigned long when)
278 {
279 	if (!timer_pending(&idev->rs_timer))
280 		in6_dev_hold(idev);
281 	mod_timer(&idev->rs_timer, jiffies + when);
282 }
283 
284 static void addrconf_mod_dad_work(struct inet6_ifaddr *ifp,
285 				   unsigned long delay)
286 {
287 	if (!delayed_work_pending(&ifp->dad_work))
288 		in6_ifa_hold(ifp);
289 	mod_delayed_work(addrconf_wq, &ifp->dad_work, delay);
290 }
291 
292 static int snmp6_alloc_dev(struct inet6_dev *idev)
293 {
294 	int i;
295 
296 	idev->stats.ipv6 = alloc_percpu(struct ipstats_mib);
297 	if (!idev->stats.ipv6)
298 		goto err_ip;
299 
300 	for_each_possible_cpu(i) {
301 		struct ipstats_mib *addrconf_stats;
302 		addrconf_stats = per_cpu_ptr(idev->stats.ipv6, i);
303 		u64_stats_init(&addrconf_stats->syncp);
304 	}
305 
306 
307 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
308 					GFP_KERNEL);
309 	if (!idev->stats.icmpv6dev)
310 		goto err_icmp;
311 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
312 					   GFP_KERNEL);
313 	if (!idev->stats.icmpv6msgdev)
314 		goto err_icmpmsg;
315 
316 	return 0;
317 
318 err_icmpmsg:
319 	kfree(idev->stats.icmpv6dev);
320 err_icmp:
321 	free_percpu(idev->stats.ipv6);
322 err_ip:
323 	return -ENOMEM;
324 }
325 
326 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
327 {
328 	struct inet6_dev *ndev;
329 	int err = -ENOMEM;
330 
331 	ASSERT_RTNL();
332 
333 	if (dev->mtu < IPV6_MIN_MTU)
334 		return ERR_PTR(-EINVAL);
335 
336 	ndev = kzalloc(sizeof(struct inet6_dev), GFP_KERNEL);
337 	if (ndev == NULL)
338 		return ERR_PTR(err);
339 
340 	rwlock_init(&ndev->lock);
341 	ndev->dev = dev;
342 	INIT_LIST_HEAD(&ndev->addr_list);
343 	setup_timer(&ndev->rs_timer, addrconf_rs_timer,
344 		    (unsigned long)ndev);
345 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
346 	ndev->cnf.mtu6 = dev->mtu;
347 	ndev->cnf.sysctl = NULL;
348 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
349 	if (ndev->nd_parms == NULL) {
350 		kfree(ndev);
351 		return ERR_PTR(err);
352 	}
353 	if (ndev->cnf.forwarding)
354 		dev_disable_lro(dev);
355 	/* We refer to the device */
356 	dev_hold(dev);
357 
358 	if (snmp6_alloc_dev(ndev) < 0) {
359 		ADBG(KERN_WARNING
360 			"%s: cannot allocate memory for statistics; dev=%s.\n",
361 			__func__, dev->name);
362 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
363 		dev_put(dev);
364 		kfree(ndev);
365 		return ERR_PTR(err);
366 	}
367 
368 	if (snmp6_register_dev(ndev) < 0) {
369 		ADBG(KERN_WARNING
370 			"%s: cannot create /proc/net/dev_snmp6/%s\n",
371 			__func__, dev->name);
372 		goto err_release;
373 	}
374 
375 	/* One reference from device.  We must do this before
376 	 * we invoke __ipv6_regen_rndid().
377 	 */
378 	in6_dev_hold(ndev);
379 
380 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
381 		ndev->cnf.accept_dad = -1;
382 
383 #if IS_ENABLED(CONFIG_IPV6_SIT)
384 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
385 		pr_info("%s: Disabled Multicast RS\n", dev->name);
386 		ndev->cnf.rtr_solicits = 0;
387 	}
388 #endif
389 
390 	INIT_LIST_HEAD(&ndev->tempaddr_list);
391 	setup_timer(&ndev->regen_timer, ipv6_regen_rndid, (unsigned long)ndev);
392 	if ((dev->flags&IFF_LOOPBACK) ||
393 	    dev->type == ARPHRD_TUNNEL ||
394 	    dev->type == ARPHRD_TUNNEL6 ||
395 	    dev->type == ARPHRD_SIT ||
396 	    dev->type == ARPHRD_NONE) {
397 		ndev->cnf.use_tempaddr = -1;
398 	} else {
399 		in6_dev_hold(ndev);
400 		ipv6_regen_rndid((unsigned long) ndev);
401 	}
402 
403 	ndev->token = in6addr_any;
404 
405 	if (netif_running(dev) && addrconf_qdisc_ok(dev))
406 		ndev->if_flags |= IF_READY;
407 
408 	ipv6_mc_init_dev(ndev);
409 	ndev->tstamp = jiffies;
410 	err = addrconf_sysctl_register(ndev);
411 	if (err) {
412 		ipv6_mc_destroy_dev(ndev);
413 		del_timer(&ndev->regen_timer);
414 		goto err_release;
415 	}
416 	/* protected by rtnl_lock */
417 	rcu_assign_pointer(dev->ip6_ptr, ndev);
418 
419 	/* Join interface-local all-node multicast group */
420 	ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes);
421 
422 	/* Join all-node multicast group */
423 	ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
424 
425 	/* Join all-router multicast group if forwarding is set */
426 	if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
427 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
428 
429 	return ndev;
430 
431 err_release:
432 	neigh_parms_release(&nd_tbl, ndev->nd_parms);
433 	ndev->dead = 1;
434 	in6_dev_finish_destroy(ndev);
435 	return ERR_PTR(err);
436 }
437 
438 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
439 {
440 	struct inet6_dev *idev;
441 
442 	ASSERT_RTNL();
443 
444 	idev = __in6_dev_get(dev);
445 	if (!idev) {
446 		idev = ipv6_add_dev(dev);
447 		if (IS_ERR(idev))
448 			return NULL;
449 	}
450 
451 	if (dev->flags&IFF_UP)
452 		ipv6_mc_up(idev);
453 	return idev;
454 }
455 
456 static int inet6_netconf_msgsize_devconf(int type)
457 {
458 	int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
459 		    + nla_total_size(4);	/* NETCONFA_IFINDEX */
460 
461 	/* type -1 is used for ALL */
462 	if (type == -1 || type == NETCONFA_FORWARDING)
463 		size += nla_total_size(4);
464 #ifdef CONFIG_IPV6_MROUTE
465 	if (type == -1 || type == NETCONFA_MC_FORWARDING)
466 		size += nla_total_size(4);
467 #endif
468 	if (type == -1 || type == NETCONFA_PROXY_NEIGH)
469 		size += nla_total_size(4);
470 
471 	return size;
472 }
473 
474 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
475 				      struct ipv6_devconf *devconf, u32 portid,
476 				      u32 seq, int event, unsigned int flags,
477 				      int type)
478 {
479 	struct nlmsghdr  *nlh;
480 	struct netconfmsg *ncm;
481 
482 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
483 			flags);
484 	if (nlh == NULL)
485 		return -EMSGSIZE;
486 
487 	ncm = nlmsg_data(nlh);
488 	ncm->ncm_family = AF_INET6;
489 
490 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
491 		goto nla_put_failure;
492 
493 	/* type -1 is used for ALL */
494 	if ((type == -1 || type == NETCONFA_FORWARDING) &&
495 	    nla_put_s32(skb, NETCONFA_FORWARDING, devconf->forwarding) < 0)
496 		goto nla_put_failure;
497 #ifdef CONFIG_IPV6_MROUTE
498 	if ((type == -1 || type == NETCONFA_MC_FORWARDING) &&
499 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
500 			devconf->mc_forwarding) < 0)
501 		goto nla_put_failure;
502 #endif
503 	if ((type == -1 || type == NETCONFA_PROXY_NEIGH) &&
504 	    nla_put_s32(skb, NETCONFA_PROXY_NEIGH, devconf->proxy_ndp) < 0)
505 		goto nla_put_failure;
506 
507 	nlmsg_end(skb, nlh);
508 	return 0;
509 
510 nla_put_failure:
511 	nlmsg_cancel(skb, nlh);
512 	return -EMSGSIZE;
513 }
514 
515 void inet6_netconf_notify_devconf(struct net *net, int type, int ifindex,
516 				  struct ipv6_devconf *devconf)
517 {
518 	struct sk_buff *skb;
519 	int err = -ENOBUFS;
520 
521 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_ATOMIC);
522 	if (skb == NULL)
523 		goto errout;
524 
525 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
526 					 RTM_NEWNETCONF, 0, type);
527 	if (err < 0) {
528 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
529 		WARN_ON(err == -EMSGSIZE);
530 		kfree_skb(skb);
531 		goto errout;
532 	}
533 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_ATOMIC);
534 	return;
535 errout:
536 	rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
537 }
538 
539 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
540 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
541 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
542 	[NETCONFA_PROXY_NEIGH]	= { .len = sizeof(int) },
543 };
544 
545 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
546 				     struct nlmsghdr *nlh)
547 {
548 	struct net *net = sock_net(in_skb->sk);
549 	struct nlattr *tb[NETCONFA_MAX+1];
550 	struct netconfmsg *ncm;
551 	struct sk_buff *skb;
552 	struct ipv6_devconf *devconf;
553 	struct inet6_dev *in6_dev;
554 	struct net_device *dev;
555 	int ifindex;
556 	int err;
557 
558 	err = nlmsg_parse(nlh, sizeof(*ncm), tb, NETCONFA_MAX,
559 			  devconf_ipv6_policy);
560 	if (err < 0)
561 		goto errout;
562 
563 	err = EINVAL;
564 	if (!tb[NETCONFA_IFINDEX])
565 		goto errout;
566 
567 	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
568 	switch (ifindex) {
569 	case NETCONFA_IFINDEX_ALL:
570 		devconf = net->ipv6.devconf_all;
571 		break;
572 	case NETCONFA_IFINDEX_DEFAULT:
573 		devconf = net->ipv6.devconf_dflt;
574 		break;
575 	default:
576 		dev = __dev_get_by_index(net, ifindex);
577 		if (dev == NULL)
578 			goto errout;
579 		in6_dev = __in6_dev_get(dev);
580 		if (in6_dev == NULL)
581 			goto errout;
582 		devconf = &in6_dev->cnf;
583 		break;
584 	}
585 
586 	err = -ENOBUFS;
587 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(-1), GFP_ATOMIC);
588 	if (skb == NULL)
589 		goto errout;
590 
591 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
592 					 NETLINK_CB(in_skb).portid,
593 					 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
594 					 -1);
595 	if (err < 0) {
596 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
597 		WARN_ON(err == -EMSGSIZE);
598 		kfree_skb(skb);
599 		goto errout;
600 	}
601 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
602 errout:
603 	return err;
604 }
605 
606 static int inet6_netconf_dump_devconf(struct sk_buff *skb,
607 				      struct netlink_callback *cb)
608 {
609 	struct net *net = sock_net(skb->sk);
610 	int h, s_h;
611 	int idx, s_idx;
612 	struct net_device *dev;
613 	struct inet6_dev *idev;
614 	struct hlist_head *head;
615 
616 	s_h = cb->args[0];
617 	s_idx = idx = cb->args[1];
618 
619 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
620 		idx = 0;
621 		head = &net->dev_index_head[h];
622 		rcu_read_lock();
623 		cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^
624 			  net->dev_base_seq;
625 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
626 			if (idx < s_idx)
627 				goto cont;
628 			idev = __in6_dev_get(dev);
629 			if (!idev)
630 				goto cont;
631 
632 			if (inet6_netconf_fill_devconf(skb, dev->ifindex,
633 						       &idev->cnf,
634 						       NETLINK_CB(cb->skb).portid,
635 						       cb->nlh->nlmsg_seq,
636 						       RTM_NEWNETCONF,
637 						       NLM_F_MULTI,
638 						       -1) < 0) {
639 				rcu_read_unlock();
640 				goto done;
641 			}
642 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
643 cont:
644 			idx++;
645 		}
646 		rcu_read_unlock();
647 	}
648 	if (h == NETDEV_HASHENTRIES) {
649 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
650 					       net->ipv6.devconf_all,
651 					       NETLINK_CB(cb->skb).portid,
652 					       cb->nlh->nlmsg_seq,
653 					       RTM_NEWNETCONF, NLM_F_MULTI,
654 					       -1) < 0)
655 			goto done;
656 		else
657 			h++;
658 	}
659 	if (h == NETDEV_HASHENTRIES + 1) {
660 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
661 					       net->ipv6.devconf_dflt,
662 					       NETLINK_CB(cb->skb).portid,
663 					       cb->nlh->nlmsg_seq,
664 					       RTM_NEWNETCONF, NLM_F_MULTI,
665 					       -1) < 0)
666 			goto done;
667 		else
668 			h++;
669 	}
670 done:
671 	cb->args[0] = h;
672 	cb->args[1] = idx;
673 
674 	return skb->len;
675 }
676 
677 #ifdef CONFIG_SYSCTL
678 static void dev_forward_change(struct inet6_dev *idev)
679 {
680 	struct net_device *dev;
681 	struct inet6_ifaddr *ifa;
682 
683 	if (!idev)
684 		return;
685 	dev = idev->dev;
686 	if (idev->cnf.forwarding)
687 		dev_disable_lro(dev);
688 	if (dev->flags & IFF_MULTICAST) {
689 		if (idev->cnf.forwarding) {
690 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
691 			ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
692 			ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters);
693 		} else {
694 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
695 			ipv6_dev_mc_dec(dev, &in6addr_interfacelocal_allrouters);
696 			ipv6_dev_mc_dec(dev, &in6addr_sitelocal_allrouters);
697 		}
698 	}
699 
700 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
701 		if (ifa->flags&IFA_F_TENTATIVE)
702 			continue;
703 		if (idev->cnf.forwarding)
704 			addrconf_join_anycast(ifa);
705 		else
706 			addrconf_leave_anycast(ifa);
707 	}
708 	inet6_netconf_notify_devconf(dev_net(dev), NETCONFA_FORWARDING,
709 				     dev->ifindex, &idev->cnf);
710 }
711 
712 
713 static void addrconf_forward_change(struct net *net, __s32 newf)
714 {
715 	struct net_device *dev;
716 	struct inet6_dev *idev;
717 
718 	for_each_netdev(net, dev) {
719 		idev = __in6_dev_get(dev);
720 		if (idev) {
721 			int changed = (!idev->cnf.forwarding) ^ (!newf);
722 			idev->cnf.forwarding = newf;
723 			if (changed)
724 				dev_forward_change(idev);
725 		}
726 	}
727 }
728 
729 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int newf)
730 {
731 	struct net *net;
732 	int old;
733 
734 	if (!rtnl_trylock())
735 		return restart_syscall();
736 
737 	net = (struct net *)table->extra2;
738 	old = *p;
739 	*p = newf;
740 
741 	if (p == &net->ipv6.devconf_dflt->forwarding) {
742 		if ((!newf) ^ (!old))
743 			inet6_netconf_notify_devconf(net, NETCONFA_FORWARDING,
744 						     NETCONFA_IFINDEX_DEFAULT,
745 						     net->ipv6.devconf_dflt);
746 		rtnl_unlock();
747 		return 0;
748 	}
749 
750 	if (p == &net->ipv6.devconf_all->forwarding) {
751 		net->ipv6.devconf_dflt->forwarding = newf;
752 		addrconf_forward_change(net, newf);
753 		if ((!newf) ^ (!old))
754 			inet6_netconf_notify_devconf(net, NETCONFA_FORWARDING,
755 						     NETCONFA_IFINDEX_ALL,
756 						     net->ipv6.devconf_all);
757 	} else if ((!newf) ^ (!old))
758 		dev_forward_change((struct inet6_dev *)table->extra1);
759 	rtnl_unlock();
760 
761 	if (newf)
762 		rt6_purge_dflt_routers(net);
763 	return 1;
764 }
765 #endif
766 
767 /* Nobody refers to this ifaddr, destroy it */
768 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
769 {
770 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
771 
772 #ifdef NET_REFCNT_DEBUG
773 	pr_debug("%s\n", __func__);
774 #endif
775 
776 	in6_dev_put(ifp->idev);
777 
778 	if (cancel_delayed_work(&ifp->dad_work))
779 		pr_notice("delayed DAD work was pending while freeing ifa=%p\n",
780 			  ifp);
781 
782 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
783 		pr_warn("Freeing alive inet6 address %p\n", ifp);
784 		return;
785 	}
786 	ip6_rt_put(ifp->rt);
787 
788 	kfree_rcu(ifp, rcu);
789 }
790 
791 static void
792 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
793 {
794 	struct list_head *p;
795 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
796 
797 	/*
798 	 * Each device address list is sorted in order of scope -
799 	 * global before linklocal.
800 	 */
801 	list_for_each(p, &idev->addr_list) {
802 		struct inet6_ifaddr *ifa
803 			= list_entry(p, struct inet6_ifaddr, if_list);
804 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
805 			break;
806 	}
807 
808 	list_add_tail(&ifp->if_list, p);
809 }
810 
811 static u32 inet6_addr_hash(const struct in6_addr *addr)
812 {
813 	return hash_32(ipv6_addr_hash(addr), IN6_ADDR_HSIZE_SHIFT);
814 }
815 
816 /* On success it returns ifp with increased reference count */
817 
818 static struct inet6_ifaddr *
819 ipv6_add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
820 	      const struct in6_addr *peer_addr, int pfxlen,
821 	      int scope, u32 flags, u32 valid_lft, u32 prefered_lft)
822 {
823 	struct inet6_ifaddr *ifa = NULL;
824 	struct rt6_info *rt;
825 	unsigned int hash;
826 	int err = 0;
827 	int addr_type = ipv6_addr_type(addr);
828 
829 	if (addr_type == IPV6_ADDR_ANY ||
830 	    addr_type & IPV6_ADDR_MULTICAST ||
831 	    (!(idev->dev->flags & IFF_LOOPBACK) &&
832 	     addr_type & IPV6_ADDR_LOOPBACK))
833 		return ERR_PTR(-EADDRNOTAVAIL);
834 
835 	rcu_read_lock_bh();
836 	if (idev->dead) {
837 		err = -ENODEV;			/*XXX*/
838 		goto out2;
839 	}
840 
841 	if (idev->cnf.disable_ipv6) {
842 		err = -EACCES;
843 		goto out2;
844 	}
845 
846 	spin_lock(&addrconf_hash_lock);
847 
848 	/* Ignore adding duplicate addresses on an interface */
849 	if (ipv6_chk_same_addr(dev_net(idev->dev), addr, idev->dev)) {
850 		ADBG("ipv6_add_addr: already assigned\n");
851 		err = -EEXIST;
852 		goto out;
853 	}
854 
855 	ifa = kzalloc(sizeof(struct inet6_ifaddr), GFP_ATOMIC);
856 
857 	if (ifa == NULL) {
858 		ADBG("ipv6_add_addr: malloc failed\n");
859 		err = -ENOBUFS;
860 		goto out;
861 	}
862 
863 	rt = addrconf_dst_alloc(idev, addr, false);
864 	if (IS_ERR(rt)) {
865 		err = PTR_ERR(rt);
866 		goto out;
867 	}
868 
869 	neigh_parms_data_state_setall(idev->nd_parms);
870 
871 	ifa->addr = *addr;
872 	if (peer_addr)
873 		ifa->peer_addr = *peer_addr;
874 
875 	spin_lock_init(&ifa->lock);
876 	INIT_DELAYED_WORK(&ifa->dad_work, addrconf_dad_work);
877 	INIT_HLIST_NODE(&ifa->addr_lst);
878 	ifa->scope = scope;
879 	ifa->prefix_len = pfxlen;
880 	ifa->flags = flags | IFA_F_TENTATIVE;
881 	ifa->valid_lft = valid_lft;
882 	ifa->prefered_lft = prefered_lft;
883 	ifa->cstamp = ifa->tstamp = jiffies;
884 	ifa->tokenized = false;
885 
886 	ifa->rt = rt;
887 
888 	ifa->idev = idev;
889 	in6_dev_hold(idev);
890 	/* For caller */
891 	in6_ifa_hold(ifa);
892 
893 	/* Add to big hash table */
894 	hash = inet6_addr_hash(addr);
895 
896 	hlist_add_head_rcu(&ifa->addr_lst, &inet6_addr_lst[hash]);
897 	spin_unlock(&addrconf_hash_lock);
898 
899 	write_lock(&idev->lock);
900 	/* Add to inet6_dev unicast addr list. */
901 	ipv6_link_dev_addr(idev, ifa);
902 
903 	if (ifa->flags&IFA_F_TEMPORARY) {
904 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
905 		in6_ifa_hold(ifa);
906 	}
907 
908 	in6_ifa_hold(ifa);
909 	write_unlock(&idev->lock);
910 out2:
911 	rcu_read_unlock_bh();
912 
913 	if (likely(err == 0))
914 		inet6addr_notifier_call_chain(NETDEV_UP, ifa);
915 	else {
916 		kfree(ifa);
917 		ifa = ERR_PTR(err);
918 	}
919 
920 	return ifa;
921 out:
922 	spin_unlock(&addrconf_hash_lock);
923 	goto out2;
924 }
925 
926 enum cleanup_prefix_rt_t {
927 	CLEANUP_PREFIX_RT_NOP,    /* no cleanup action for prefix route */
928 	CLEANUP_PREFIX_RT_DEL,    /* delete the prefix route */
929 	CLEANUP_PREFIX_RT_EXPIRE, /* update the lifetime of the prefix route */
930 };
931 
932 /*
933  * Check, whether the prefix for ifp would still need a prefix route
934  * after deleting ifp. The function returns one of the CLEANUP_PREFIX_RT_*
935  * constants.
936  *
937  * 1) we don't purge prefix if address was not permanent.
938  *    prefix is managed by its own lifetime.
939  * 2) we also don't purge, if the address was IFA_F_NOPREFIXROUTE.
940  * 3) if there are no addresses, delete prefix.
941  * 4) if there are still other permanent address(es),
942  *    corresponding prefix is still permanent.
943  * 5) if there are still other addresses with IFA_F_NOPREFIXROUTE,
944  *    don't purge the prefix, assume user space is managing it.
945  * 6) otherwise, update prefix lifetime to the
946  *    longest valid lifetime among the corresponding
947  *    addresses on the device.
948  *    Note: subsequent RA will update lifetime.
949  **/
950 static enum cleanup_prefix_rt_t
951 check_cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long *expires)
952 {
953 	struct inet6_ifaddr *ifa;
954 	struct inet6_dev *idev = ifp->idev;
955 	unsigned long lifetime;
956 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_DEL;
957 
958 	*expires = jiffies;
959 
960 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
961 		if (ifa == ifp)
962 			continue;
963 		if (!ipv6_prefix_equal(&ifa->addr, &ifp->addr,
964 				       ifp->prefix_len))
965 			continue;
966 		if (ifa->flags & (IFA_F_PERMANENT | IFA_F_NOPREFIXROUTE))
967 			return CLEANUP_PREFIX_RT_NOP;
968 
969 		action = CLEANUP_PREFIX_RT_EXPIRE;
970 
971 		spin_lock(&ifa->lock);
972 
973 		lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
974 		/*
975 		 * Note: Because this address is
976 		 * not permanent, lifetime <
977 		 * LONG_MAX / HZ here.
978 		 */
979 		if (time_before(*expires, ifa->tstamp + lifetime * HZ))
980 			*expires = ifa->tstamp + lifetime * HZ;
981 		spin_unlock(&ifa->lock);
982 	}
983 
984 	return action;
985 }
986 
987 static void
988 cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long expires, bool del_rt)
989 {
990 	struct rt6_info *rt;
991 
992 	rt = addrconf_get_prefix_route(&ifp->addr,
993 				       ifp->prefix_len,
994 				       ifp->idev->dev,
995 				       0, RTF_GATEWAY | RTF_DEFAULT);
996 	if (rt) {
997 		if (del_rt)
998 			ip6_del_rt(rt);
999 		else {
1000 			if (!(rt->rt6i_flags & RTF_EXPIRES))
1001 				rt6_set_expires(rt, expires);
1002 			ip6_rt_put(rt);
1003 		}
1004 	}
1005 }
1006 
1007 
1008 /* This function wants to get referenced ifp and releases it before return */
1009 
1010 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
1011 {
1012 	int state;
1013 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_NOP;
1014 	unsigned long expires;
1015 
1016 	ASSERT_RTNL();
1017 
1018 	spin_lock_bh(&ifp->lock);
1019 	state = ifp->state;
1020 	ifp->state = INET6_IFADDR_STATE_DEAD;
1021 	spin_unlock_bh(&ifp->lock);
1022 
1023 	if (state == INET6_IFADDR_STATE_DEAD)
1024 		goto out;
1025 
1026 	spin_lock_bh(&addrconf_hash_lock);
1027 	hlist_del_init_rcu(&ifp->addr_lst);
1028 	spin_unlock_bh(&addrconf_hash_lock);
1029 
1030 	write_lock_bh(&ifp->idev->lock);
1031 
1032 	if (ifp->flags&IFA_F_TEMPORARY) {
1033 		list_del(&ifp->tmp_list);
1034 		if (ifp->ifpub) {
1035 			in6_ifa_put(ifp->ifpub);
1036 			ifp->ifpub = NULL;
1037 		}
1038 		__in6_ifa_put(ifp);
1039 	}
1040 
1041 	if (ifp->flags & IFA_F_PERMANENT && !(ifp->flags & IFA_F_NOPREFIXROUTE))
1042 		action = check_cleanup_prefix_route(ifp, &expires);
1043 
1044 	list_del_init(&ifp->if_list);
1045 	__in6_ifa_put(ifp);
1046 
1047 	write_unlock_bh(&ifp->idev->lock);
1048 
1049 	addrconf_del_dad_work(ifp);
1050 
1051 	ipv6_ifa_notify(RTM_DELADDR, ifp);
1052 
1053 	inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);
1054 
1055 	if (action != CLEANUP_PREFIX_RT_NOP) {
1056 		cleanup_prefix_route(ifp, expires,
1057 			action == CLEANUP_PREFIX_RT_DEL);
1058 	}
1059 
1060 	/* clean up prefsrc entries */
1061 	rt6_remove_prefsrc(ifp);
1062 out:
1063 	in6_ifa_put(ifp);
1064 }
1065 
1066 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp, struct inet6_ifaddr *ift)
1067 {
1068 	struct inet6_dev *idev = ifp->idev;
1069 	struct in6_addr addr, *tmpaddr;
1070 	unsigned long tmp_prefered_lft, tmp_valid_lft, tmp_tstamp, age;
1071 	unsigned long regen_advance;
1072 	int tmp_plen;
1073 	int ret = 0;
1074 	u32 addr_flags;
1075 	unsigned long now = jiffies;
1076 
1077 	write_lock_bh(&idev->lock);
1078 	if (ift) {
1079 		spin_lock_bh(&ift->lock);
1080 		memcpy(&addr.s6_addr[8], &ift->addr.s6_addr[8], 8);
1081 		spin_unlock_bh(&ift->lock);
1082 		tmpaddr = &addr;
1083 	} else {
1084 		tmpaddr = NULL;
1085 	}
1086 retry:
1087 	in6_dev_hold(idev);
1088 	if (idev->cnf.use_tempaddr <= 0) {
1089 		write_unlock_bh(&idev->lock);
1090 		pr_info("%s: use_tempaddr is disabled\n", __func__);
1091 		in6_dev_put(idev);
1092 		ret = -1;
1093 		goto out;
1094 	}
1095 	spin_lock_bh(&ifp->lock);
1096 	if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
1097 		idev->cnf.use_tempaddr = -1;	/*XXX*/
1098 		spin_unlock_bh(&ifp->lock);
1099 		write_unlock_bh(&idev->lock);
1100 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1101 			__func__);
1102 		in6_dev_put(idev);
1103 		ret = -1;
1104 		goto out;
1105 	}
1106 	in6_ifa_hold(ifp);
1107 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1108 	__ipv6_try_regen_rndid(idev, tmpaddr);
1109 	memcpy(&addr.s6_addr[8], idev->rndid, 8);
1110 	age = (now - ifp->tstamp) / HZ;
1111 	tmp_valid_lft = min_t(__u32,
1112 			      ifp->valid_lft,
1113 			      idev->cnf.temp_valid_lft + age);
1114 	tmp_prefered_lft = min_t(__u32,
1115 				 ifp->prefered_lft,
1116 				 idev->cnf.temp_prefered_lft + age -
1117 				 idev->cnf.max_desync_factor);
1118 	tmp_plen = ifp->prefix_len;
1119 	tmp_tstamp = ifp->tstamp;
1120 	spin_unlock_bh(&ifp->lock);
1121 
1122 	regen_advance = idev->cnf.regen_max_retry *
1123 			idev->cnf.dad_transmits *
1124 			NEIGH_VAR(idev->nd_parms, RETRANS_TIME) / HZ;
1125 	write_unlock_bh(&idev->lock);
1126 
1127 	/* A temporary address is created only if this calculated Preferred
1128 	 * Lifetime is greater than REGEN_ADVANCE time units.  In particular,
1129 	 * an implementation must not create a temporary address with a zero
1130 	 * Preferred Lifetime.
1131 	 * Use age calculation as in addrconf_verify to avoid unnecessary
1132 	 * temporary addresses being generated.
1133 	 */
1134 	age = (now - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
1135 	if (tmp_prefered_lft <= regen_advance + age) {
1136 		in6_ifa_put(ifp);
1137 		in6_dev_put(idev);
1138 		ret = -1;
1139 		goto out;
1140 	}
1141 
1142 	addr_flags = IFA_F_TEMPORARY;
1143 	/* set in addrconf_prefix_rcv() */
1144 	if (ifp->flags & IFA_F_OPTIMISTIC)
1145 		addr_flags |= IFA_F_OPTIMISTIC;
1146 
1147 	ift = ipv6_add_addr(idev, &addr, NULL, tmp_plen,
1148 			    ipv6_addr_scope(&addr), addr_flags,
1149 			    tmp_valid_lft, tmp_prefered_lft);
1150 	if (IS_ERR(ift)) {
1151 		in6_ifa_put(ifp);
1152 		in6_dev_put(idev);
1153 		pr_info("%s: retry temporary address regeneration\n", __func__);
1154 		tmpaddr = &addr;
1155 		write_lock_bh(&idev->lock);
1156 		goto retry;
1157 	}
1158 
1159 	spin_lock_bh(&ift->lock);
1160 	ift->ifpub = ifp;
1161 	ift->cstamp = now;
1162 	ift->tstamp = tmp_tstamp;
1163 	spin_unlock_bh(&ift->lock);
1164 
1165 	addrconf_dad_start(ift);
1166 	in6_ifa_put(ift);
1167 	in6_dev_put(idev);
1168 out:
1169 	return ret;
1170 }
1171 
1172 /*
1173  *	Choose an appropriate source address (RFC3484)
1174  */
1175 enum {
1176 	IPV6_SADDR_RULE_INIT = 0,
1177 	IPV6_SADDR_RULE_LOCAL,
1178 	IPV6_SADDR_RULE_SCOPE,
1179 	IPV6_SADDR_RULE_PREFERRED,
1180 #ifdef CONFIG_IPV6_MIP6
1181 	IPV6_SADDR_RULE_HOA,
1182 #endif
1183 	IPV6_SADDR_RULE_OIF,
1184 	IPV6_SADDR_RULE_LABEL,
1185 	IPV6_SADDR_RULE_PRIVACY,
1186 	IPV6_SADDR_RULE_ORCHID,
1187 	IPV6_SADDR_RULE_PREFIX,
1188 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1189 	IPV6_SADDR_RULE_NOT_OPTIMISTIC,
1190 #endif
1191 	IPV6_SADDR_RULE_MAX
1192 };
1193 
1194 struct ipv6_saddr_score {
1195 	int			rule;
1196 	int			addr_type;
1197 	struct inet6_ifaddr	*ifa;
1198 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1199 	int			scopedist;
1200 	int			matchlen;
1201 };
1202 
1203 struct ipv6_saddr_dst {
1204 	const struct in6_addr *addr;
1205 	int ifindex;
1206 	int scope;
1207 	int label;
1208 	unsigned int prefs;
1209 };
1210 
1211 static inline int ipv6_saddr_preferred(int type)
1212 {
1213 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1214 		return 1;
1215 	return 0;
1216 }
1217 
1218 static inline bool ipv6_use_optimistic_addr(struct inet6_dev *idev)
1219 {
1220 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1221 	return idev && idev->cnf.optimistic_dad && idev->cnf.use_optimistic;
1222 #else
1223 	return false;
1224 #endif
1225 }
1226 
1227 static int ipv6_get_saddr_eval(struct net *net,
1228 			       struct ipv6_saddr_score *score,
1229 			       struct ipv6_saddr_dst *dst,
1230 			       int i)
1231 {
1232 	int ret;
1233 
1234 	if (i <= score->rule) {
1235 		switch (i) {
1236 		case IPV6_SADDR_RULE_SCOPE:
1237 			ret = score->scopedist;
1238 			break;
1239 		case IPV6_SADDR_RULE_PREFIX:
1240 			ret = score->matchlen;
1241 			break;
1242 		default:
1243 			ret = !!test_bit(i, score->scorebits);
1244 		}
1245 		goto out;
1246 	}
1247 
1248 	switch (i) {
1249 	case IPV6_SADDR_RULE_INIT:
1250 		/* Rule 0: remember if hiscore is not ready yet */
1251 		ret = !!score->ifa;
1252 		break;
1253 	case IPV6_SADDR_RULE_LOCAL:
1254 		/* Rule 1: Prefer same address */
1255 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1256 		break;
1257 	case IPV6_SADDR_RULE_SCOPE:
1258 		/* Rule 2: Prefer appropriate scope
1259 		 *
1260 		 *      ret
1261 		 *       ^
1262 		 *    -1 |  d 15
1263 		 *    ---+--+-+---> scope
1264 		 *       |
1265 		 *       |             d is scope of the destination.
1266 		 *  B-d  |  \
1267 		 *       |   \      <- smaller scope is better if
1268 		 *  B-15 |    \        if scope is enough for destination.
1269 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1270 		 * d-C-1 | /
1271 		 *       |/         <- greater is better
1272 		 *   -C  /             if scope is not enough for destination.
1273 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1274 		 *
1275 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1276 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1277 		 * Assume B = 0 and we get C > 29.
1278 		 */
1279 		ret = __ipv6_addr_src_scope(score->addr_type);
1280 		if (ret >= dst->scope)
1281 			ret = -ret;
1282 		else
1283 			ret -= 128;	/* 30 is enough */
1284 		score->scopedist = ret;
1285 		break;
1286 	case IPV6_SADDR_RULE_PREFERRED:
1287 	    {
1288 		/* Rule 3: Avoid deprecated and optimistic addresses */
1289 		u8 avoid = IFA_F_DEPRECATED;
1290 
1291 		if (!ipv6_use_optimistic_addr(score->ifa->idev))
1292 			avoid |= IFA_F_OPTIMISTIC;
1293 		ret = ipv6_saddr_preferred(score->addr_type) ||
1294 		      !(score->ifa->flags & avoid);
1295 		break;
1296 	    }
1297 #ifdef CONFIG_IPV6_MIP6
1298 	case IPV6_SADDR_RULE_HOA:
1299 	    {
1300 		/* Rule 4: Prefer home address */
1301 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1302 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1303 		break;
1304 	    }
1305 #endif
1306 	case IPV6_SADDR_RULE_OIF:
1307 		/* Rule 5: Prefer outgoing interface */
1308 		ret = (!dst->ifindex ||
1309 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1310 		break;
1311 	case IPV6_SADDR_RULE_LABEL:
1312 		/* Rule 6: Prefer matching label */
1313 		ret = ipv6_addr_label(net,
1314 				      &score->ifa->addr, score->addr_type,
1315 				      score->ifa->idev->dev->ifindex) == dst->label;
1316 		break;
1317 	case IPV6_SADDR_RULE_PRIVACY:
1318 	    {
1319 		/* Rule 7: Prefer public address
1320 		 * Note: prefer temporary address if use_tempaddr >= 2
1321 		 */
1322 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1323 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1324 				score->ifa->idev->cnf.use_tempaddr >= 2;
1325 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1326 		break;
1327 	    }
1328 	case IPV6_SADDR_RULE_ORCHID:
1329 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1330 		 *	    non-ORCHID vs non-ORCHID
1331 		 */
1332 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1333 			ipv6_addr_orchid(dst->addr));
1334 		break;
1335 	case IPV6_SADDR_RULE_PREFIX:
1336 		/* Rule 8: Use longest matching prefix */
1337 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1338 		if (ret > score->ifa->prefix_len)
1339 			ret = score->ifa->prefix_len;
1340 		score->matchlen = ret;
1341 		break;
1342 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1343 	case IPV6_SADDR_RULE_NOT_OPTIMISTIC:
1344 		/* Optimistic addresses still have lower precedence than other
1345 		 * preferred addresses.
1346 		 */
1347 		ret = !(score->ifa->flags & IFA_F_OPTIMISTIC);
1348 		break;
1349 #endif
1350 	default:
1351 		ret = 0;
1352 	}
1353 
1354 	if (ret)
1355 		__set_bit(i, score->scorebits);
1356 	score->rule = i;
1357 out:
1358 	return ret;
1359 }
1360 
1361 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1362 		       const struct in6_addr *daddr, unsigned int prefs,
1363 		       struct in6_addr *saddr)
1364 {
1365 	struct ipv6_saddr_score scores[2],
1366 				*score = &scores[0], *hiscore = &scores[1];
1367 	struct ipv6_saddr_dst dst;
1368 	struct net_device *dev;
1369 	int dst_type;
1370 
1371 	dst_type = __ipv6_addr_type(daddr);
1372 	dst.addr = daddr;
1373 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1374 	dst.scope = __ipv6_addr_src_scope(dst_type);
1375 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1376 	dst.prefs = prefs;
1377 
1378 	hiscore->rule = -1;
1379 	hiscore->ifa = NULL;
1380 
1381 	rcu_read_lock();
1382 
1383 	for_each_netdev_rcu(net, dev) {
1384 		struct inet6_dev *idev;
1385 
1386 		/* Candidate Source Address (section 4)
1387 		 *  - multicast and link-local destination address,
1388 		 *    the set of candidate source address MUST only
1389 		 *    include addresses assigned to interfaces
1390 		 *    belonging to the same link as the outgoing
1391 		 *    interface.
1392 		 * (- For site-local destination addresses, the
1393 		 *    set of candidate source addresses MUST only
1394 		 *    include addresses assigned to interfaces
1395 		 *    belonging to the same site as the outgoing
1396 		 *    interface.)
1397 		 */
1398 		if (((dst_type & IPV6_ADDR_MULTICAST) ||
1399 		     dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL) &&
1400 		    dst.ifindex && dev->ifindex != dst.ifindex)
1401 			continue;
1402 
1403 		idev = __in6_dev_get(dev);
1404 		if (!idev)
1405 			continue;
1406 
1407 		read_lock_bh(&idev->lock);
1408 		list_for_each_entry(score->ifa, &idev->addr_list, if_list) {
1409 			int i;
1410 
1411 			/*
1412 			 * - Tentative Address (RFC2462 section 5.4)
1413 			 *  - A tentative address is not considered
1414 			 *    "assigned to an interface" in the traditional
1415 			 *    sense, unless it is also flagged as optimistic.
1416 			 * - Candidate Source Address (section 4)
1417 			 *  - In any case, anycast addresses, multicast
1418 			 *    addresses, and the unspecified address MUST
1419 			 *    NOT be included in a candidate set.
1420 			 */
1421 			if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1422 			    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1423 				continue;
1424 
1425 			score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1426 
1427 			if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1428 				     score->addr_type & IPV6_ADDR_MULTICAST)) {
1429 				net_dbg_ratelimited("ADDRCONF: unspecified / multicast address assigned as unicast address on %s",
1430 						    dev->name);
1431 				continue;
1432 			}
1433 
1434 			score->rule = -1;
1435 			bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1436 
1437 			for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1438 				int minihiscore, miniscore;
1439 
1440 				minihiscore = ipv6_get_saddr_eval(net, hiscore, &dst, i);
1441 				miniscore = ipv6_get_saddr_eval(net, score, &dst, i);
1442 
1443 				if (minihiscore > miniscore) {
1444 					if (i == IPV6_SADDR_RULE_SCOPE &&
1445 					    score->scopedist > 0) {
1446 						/*
1447 						 * special case:
1448 						 * each remaining entry
1449 						 * has too small (not enough)
1450 						 * scope, because ifa entries
1451 						 * are sorted by their scope
1452 						 * values.
1453 						 */
1454 						goto try_nextdev;
1455 					}
1456 					break;
1457 				} else if (minihiscore < miniscore) {
1458 					if (hiscore->ifa)
1459 						in6_ifa_put(hiscore->ifa);
1460 
1461 					in6_ifa_hold(score->ifa);
1462 
1463 					swap(hiscore, score);
1464 
1465 					/* restore our iterator */
1466 					score->ifa = hiscore->ifa;
1467 
1468 					break;
1469 				}
1470 			}
1471 		}
1472 try_nextdev:
1473 		read_unlock_bh(&idev->lock);
1474 	}
1475 	rcu_read_unlock();
1476 
1477 	if (!hiscore->ifa)
1478 		return -EADDRNOTAVAIL;
1479 
1480 	*saddr = hiscore->ifa->addr;
1481 	in6_ifa_put(hiscore->ifa);
1482 	return 0;
1483 }
1484 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1485 
1486 int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr,
1487 		      u32 banned_flags)
1488 {
1489 	struct inet6_ifaddr *ifp;
1490 	int err = -EADDRNOTAVAIL;
1491 
1492 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1493 		if (ifp->scope > IFA_LINK)
1494 			break;
1495 		if (ifp->scope == IFA_LINK &&
1496 		    !(ifp->flags & banned_flags)) {
1497 			*addr = ifp->addr;
1498 			err = 0;
1499 			break;
1500 		}
1501 	}
1502 	return err;
1503 }
1504 
1505 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1506 		    u32 banned_flags)
1507 {
1508 	struct inet6_dev *idev;
1509 	int err = -EADDRNOTAVAIL;
1510 
1511 	rcu_read_lock();
1512 	idev = __in6_dev_get(dev);
1513 	if (idev) {
1514 		read_lock_bh(&idev->lock);
1515 		err = __ipv6_get_lladdr(idev, addr, banned_flags);
1516 		read_unlock_bh(&idev->lock);
1517 	}
1518 	rcu_read_unlock();
1519 	return err;
1520 }
1521 
1522 static int ipv6_count_addresses(struct inet6_dev *idev)
1523 {
1524 	int cnt = 0;
1525 	struct inet6_ifaddr *ifp;
1526 
1527 	read_lock_bh(&idev->lock);
1528 	list_for_each_entry(ifp, &idev->addr_list, if_list)
1529 		cnt++;
1530 	read_unlock_bh(&idev->lock);
1531 	return cnt;
1532 }
1533 
1534 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1535 		  const struct net_device *dev, int strict)
1536 {
1537 	return ipv6_chk_addr_and_flags(net, addr, dev, strict, IFA_F_TENTATIVE);
1538 }
1539 EXPORT_SYMBOL(ipv6_chk_addr);
1540 
1541 int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
1542 			    const struct net_device *dev, int strict,
1543 			    u32 banned_flags)
1544 {
1545 	struct inet6_ifaddr *ifp;
1546 	unsigned int hash = inet6_addr_hash(addr);
1547 	u32 ifp_flags;
1548 
1549 	rcu_read_lock_bh();
1550 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
1551 		if (!net_eq(dev_net(ifp->idev->dev), net))
1552 			continue;
1553 		/* Decouple optimistic from tentative for evaluation here.
1554 		 * Ban optimistic addresses explicitly, when required.
1555 		 */
1556 		ifp_flags = (ifp->flags&IFA_F_OPTIMISTIC)
1557 			    ? (ifp->flags&~IFA_F_TENTATIVE)
1558 			    : ifp->flags;
1559 		if (ipv6_addr_equal(&ifp->addr, addr) &&
1560 		    !(ifp_flags&banned_flags) &&
1561 		    (dev == NULL || ifp->idev->dev == dev ||
1562 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1563 			rcu_read_unlock_bh();
1564 			return 1;
1565 		}
1566 	}
1567 
1568 	rcu_read_unlock_bh();
1569 	return 0;
1570 }
1571 EXPORT_SYMBOL(ipv6_chk_addr_and_flags);
1572 
1573 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
1574 			       struct net_device *dev)
1575 {
1576 	unsigned int hash = inet6_addr_hash(addr);
1577 	struct inet6_ifaddr *ifp;
1578 
1579 	hlist_for_each_entry(ifp, &inet6_addr_lst[hash], addr_lst) {
1580 		if (!net_eq(dev_net(ifp->idev->dev), net))
1581 			continue;
1582 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1583 			if (dev == NULL || ifp->idev->dev == dev)
1584 				return true;
1585 		}
1586 	}
1587 	return false;
1588 }
1589 
1590 /* Compares an address/prefix_len with addresses on device @dev.
1591  * If one is found it returns true.
1592  */
1593 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
1594 	const unsigned int prefix_len, struct net_device *dev)
1595 {
1596 	struct inet6_dev *idev;
1597 	struct inet6_ifaddr *ifa;
1598 	bool ret = false;
1599 
1600 	rcu_read_lock();
1601 	idev = __in6_dev_get(dev);
1602 	if (idev) {
1603 		read_lock_bh(&idev->lock);
1604 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
1605 			ret = ipv6_prefix_equal(addr, &ifa->addr, prefix_len);
1606 			if (ret)
1607 				break;
1608 		}
1609 		read_unlock_bh(&idev->lock);
1610 	}
1611 	rcu_read_unlock();
1612 
1613 	return ret;
1614 }
1615 EXPORT_SYMBOL(ipv6_chk_custom_prefix);
1616 
1617 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
1618 {
1619 	struct inet6_dev *idev;
1620 	struct inet6_ifaddr *ifa;
1621 	int	onlink;
1622 
1623 	onlink = 0;
1624 	rcu_read_lock();
1625 	idev = __in6_dev_get(dev);
1626 	if (idev) {
1627 		read_lock_bh(&idev->lock);
1628 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
1629 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
1630 						   ifa->prefix_len);
1631 			if (onlink)
1632 				break;
1633 		}
1634 		read_unlock_bh(&idev->lock);
1635 	}
1636 	rcu_read_unlock();
1637 	return onlink;
1638 }
1639 EXPORT_SYMBOL(ipv6_chk_prefix);
1640 
1641 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
1642 				     struct net_device *dev, int strict)
1643 {
1644 	struct inet6_ifaddr *ifp, *result = NULL;
1645 	unsigned int hash = inet6_addr_hash(addr);
1646 
1647 	rcu_read_lock_bh();
1648 	hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[hash], addr_lst) {
1649 		if (!net_eq(dev_net(ifp->idev->dev), net))
1650 			continue;
1651 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1652 			if (dev == NULL || ifp->idev->dev == dev ||
1653 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
1654 				result = ifp;
1655 				in6_ifa_hold(ifp);
1656 				break;
1657 			}
1658 		}
1659 	}
1660 	rcu_read_unlock_bh();
1661 
1662 	return result;
1663 }
1664 
1665 /* Gets referenced address, destroys ifaddr */
1666 
1667 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
1668 {
1669 	if (ifp->flags&IFA_F_PERMANENT) {
1670 		spin_lock_bh(&ifp->lock);
1671 		addrconf_del_dad_work(ifp);
1672 		ifp->flags |= IFA_F_TENTATIVE;
1673 		if (dad_failed)
1674 			ifp->flags |= IFA_F_DADFAILED;
1675 		spin_unlock_bh(&ifp->lock);
1676 		if (dad_failed)
1677 			ipv6_ifa_notify(0, ifp);
1678 		in6_ifa_put(ifp);
1679 	} else if (ifp->flags&IFA_F_TEMPORARY) {
1680 		struct inet6_ifaddr *ifpub;
1681 		spin_lock_bh(&ifp->lock);
1682 		ifpub = ifp->ifpub;
1683 		if (ifpub) {
1684 			in6_ifa_hold(ifpub);
1685 			spin_unlock_bh(&ifp->lock);
1686 			ipv6_create_tempaddr(ifpub, ifp);
1687 			in6_ifa_put(ifpub);
1688 		} else {
1689 			spin_unlock_bh(&ifp->lock);
1690 		}
1691 		ipv6_del_addr(ifp);
1692 	} else {
1693 		ipv6_del_addr(ifp);
1694 	}
1695 }
1696 
1697 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
1698 {
1699 	int err = -ENOENT;
1700 
1701 	spin_lock_bh(&ifp->lock);
1702 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
1703 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
1704 		err = 0;
1705 	}
1706 	spin_unlock_bh(&ifp->lock);
1707 
1708 	return err;
1709 }
1710 
1711 void addrconf_dad_failure(struct inet6_ifaddr *ifp)
1712 {
1713 	struct inet6_dev *idev = ifp->idev;
1714 
1715 	if (addrconf_dad_end(ifp)) {
1716 		in6_ifa_put(ifp);
1717 		return;
1718 	}
1719 
1720 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c detected!\n",
1721 			     ifp->idev->dev->name, &ifp->addr);
1722 
1723 	if (idev->cnf.accept_dad > 1 && !idev->cnf.disable_ipv6) {
1724 		struct in6_addr addr;
1725 
1726 		addr.s6_addr32[0] = htonl(0xfe800000);
1727 		addr.s6_addr32[1] = 0;
1728 
1729 		if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
1730 		    ipv6_addr_equal(&ifp->addr, &addr)) {
1731 			/* DAD failed for link-local based on MAC address */
1732 			idev->cnf.disable_ipv6 = 1;
1733 
1734 			pr_info("%s: IPv6 being disabled!\n",
1735 				ifp->idev->dev->name);
1736 		}
1737 	}
1738 
1739 	spin_lock_bh(&ifp->lock);
1740 	/* transition from _POSTDAD to _ERRDAD */
1741 	ifp->state = INET6_IFADDR_STATE_ERRDAD;
1742 	spin_unlock_bh(&ifp->lock);
1743 
1744 	addrconf_mod_dad_work(ifp, 0);
1745 }
1746 
1747 /* Join to solicited addr multicast group.
1748  * caller must hold RTNL */
1749 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
1750 {
1751 	struct in6_addr maddr;
1752 
1753 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
1754 		return;
1755 
1756 	addrconf_addr_solict_mult(addr, &maddr);
1757 	ipv6_dev_mc_inc(dev, &maddr);
1758 }
1759 
1760 /* caller must hold RTNL */
1761 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
1762 {
1763 	struct in6_addr maddr;
1764 
1765 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
1766 		return;
1767 
1768 	addrconf_addr_solict_mult(addr, &maddr);
1769 	__ipv6_dev_mc_dec(idev, &maddr);
1770 }
1771 
1772 /* caller must hold RTNL */
1773 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
1774 {
1775 	struct in6_addr addr;
1776 
1777 	if (ifp->prefix_len >= 127) /* RFC 6164 */
1778 		return;
1779 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
1780 	if (ipv6_addr_any(&addr))
1781 		return;
1782 	__ipv6_dev_ac_inc(ifp->idev, &addr);
1783 }
1784 
1785 /* caller must hold RTNL */
1786 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
1787 {
1788 	struct in6_addr addr;
1789 
1790 	if (ifp->prefix_len >= 127) /* RFC 6164 */
1791 		return;
1792 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
1793 	if (ipv6_addr_any(&addr))
1794 		return;
1795 	__ipv6_dev_ac_dec(ifp->idev, &addr);
1796 }
1797 
1798 static int addrconf_ifid_eui48(u8 *eui, struct net_device *dev)
1799 {
1800 	if (dev->addr_len != ETH_ALEN)
1801 		return -1;
1802 	memcpy(eui, dev->dev_addr, 3);
1803 	memcpy(eui + 5, dev->dev_addr + 3, 3);
1804 
1805 	/*
1806 	 * The zSeries OSA network cards can be shared among various
1807 	 * OS instances, but the OSA cards have only one MAC address.
1808 	 * This leads to duplicate address conflicts in conjunction
1809 	 * with IPv6 if more than one instance uses the same card.
1810 	 *
1811 	 * The driver for these cards can deliver a unique 16-bit
1812 	 * identifier for each instance sharing the same card.  It is
1813 	 * placed instead of 0xFFFE in the interface identifier.  The
1814 	 * "u" bit of the interface identifier is not inverted in this
1815 	 * case.  Hence the resulting interface identifier has local
1816 	 * scope according to RFC2373.
1817 	 */
1818 	if (dev->dev_id) {
1819 		eui[3] = (dev->dev_id >> 8) & 0xFF;
1820 		eui[4] = dev->dev_id & 0xFF;
1821 	} else {
1822 		eui[3] = 0xFF;
1823 		eui[4] = 0xFE;
1824 		eui[0] ^= 2;
1825 	}
1826 	return 0;
1827 }
1828 
1829 static int addrconf_ifid_eui64(u8 *eui, struct net_device *dev)
1830 {
1831 	if (dev->addr_len != IEEE802154_ADDR_LEN)
1832 		return -1;
1833 	memcpy(eui, dev->dev_addr, 8);
1834 	eui[0] ^= 2;
1835 	return 0;
1836 }
1837 
1838 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
1839 {
1840 	union fwnet_hwaddr *ha;
1841 
1842 	if (dev->addr_len != FWNET_ALEN)
1843 		return -1;
1844 
1845 	ha = (union fwnet_hwaddr *)dev->dev_addr;
1846 
1847 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
1848 	eui[0] ^= 2;
1849 	return 0;
1850 }
1851 
1852 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
1853 {
1854 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
1855 	if (dev->addr_len != ARCNET_ALEN)
1856 		return -1;
1857 	memset(eui, 0, 7);
1858 	eui[7] = *(u8 *)dev->dev_addr;
1859 	return 0;
1860 }
1861 
1862 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
1863 {
1864 	if (dev->addr_len != INFINIBAND_ALEN)
1865 		return -1;
1866 	memcpy(eui, dev->dev_addr + 12, 8);
1867 	eui[0] |= 2;
1868 	return 0;
1869 }
1870 
1871 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
1872 {
1873 	if (addr == 0)
1874 		return -1;
1875 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
1876 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
1877 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
1878 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
1879 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
1880 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
1881 	eui[1] = 0;
1882 	eui[2] = 0x5E;
1883 	eui[3] = 0xFE;
1884 	memcpy(eui + 4, &addr, 4);
1885 	return 0;
1886 }
1887 
1888 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
1889 {
1890 	if (dev->priv_flags & IFF_ISATAP)
1891 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
1892 	return -1;
1893 }
1894 
1895 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
1896 {
1897 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
1898 }
1899 
1900 static int addrconf_ifid_ip6tnl(u8 *eui, struct net_device *dev)
1901 {
1902 	memcpy(eui, dev->perm_addr, 3);
1903 	memcpy(eui + 5, dev->perm_addr + 3, 3);
1904 	eui[3] = 0xFF;
1905 	eui[4] = 0xFE;
1906 	eui[0] ^= 2;
1907 	return 0;
1908 }
1909 
1910 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
1911 {
1912 	switch (dev->type) {
1913 	case ARPHRD_ETHER:
1914 	case ARPHRD_FDDI:
1915 		return addrconf_ifid_eui48(eui, dev);
1916 	case ARPHRD_ARCNET:
1917 		return addrconf_ifid_arcnet(eui, dev);
1918 	case ARPHRD_INFINIBAND:
1919 		return addrconf_ifid_infiniband(eui, dev);
1920 	case ARPHRD_SIT:
1921 		return addrconf_ifid_sit(eui, dev);
1922 	case ARPHRD_IPGRE:
1923 		return addrconf_ifid_gre(eui, dev);
1924 	case ARPHRD_6LOWPAN:
1925 	case ARPHRD_IEEE802154:
1926 		return addrconf_ifid_eui64(eui, dev);
1927 	case ARPHRD_IEEE1394:
1928 		return addrconf_ifid_ieee1394(eui, dev);
1929 	case ARPHRD_TUNNEL6:
1930 		return addrconf_ifid_ip6tnl(eui, dev);
1931 	}
1932 	return -1;
1933 }
1934 
1935 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
1936 {
1937 	int err = -1;
1938 	struct inet6_ifaddr *ifp;
1939 
1940 	read_lock_bh(&idev->lock);
1941 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1942 		if (ifp->scope > IFA_LINK)
1943 			break;
1944 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
1945 			memcpy(eui, ifp->addr.s6_addr+8, 8);
1946 			err = 0;
1947 			break;
1948 		}
1949 	}
1950 	read_unlock_bh(&idev->lock);
1951 	return err;
1952 }
1953 
1954 /* (re)generation of randomized interface identifier (RFC 3041 3.2, 3.5) */
1955 static void __ipv6_regen_rndid(struct inet6_dev *idev)
1956 {
1957 regen:
1958 	get_random_bytes(idev->rndid, sizeof(idev->rndid));
1959 	idev->rndid[0] &= ~0x02;
1960 
1961 	/*
1962 	 * <draft-ietf-ipngwg-temp-addresses-v2-00.txt>:
1963 	 * check if generated address is not inappropriate
1964 	 *
1965 	 *  - Reserved subnet anycast (RFC 2526)
1966 	 *	11111101 11....11 1xxxxxxx
1967 	 *  - ISATAP (RFC4214) 6.1
1968 	 *	00-00-5E-FE-xx-xx-xx-xx
1969 	 *  - value 0
1970 	 *  - XXX: already assigned to an address on the device
1971 	 */
1972 	if (idev->rndid[0] == 0xfd &&
1973 	    (idev->rndid[1]&idev->rndid[2]&idev->rndid[3]&idev->rndid[4]&idev->rndid[5]&idev->rndid[6]) == 0xff &&
1974 	    (idev->rndid[7]&0x80))
1975 		goto regen;
1976 	if ((idev->rndid[0]|idev->rndid[1]) == 0) {
1977 		if (idev->rndid[2] == 0x5e && idev->rndid[3] == 0xfe)
1978 			goto regen;
1979 		if ((idev->rndid[2]|idev->rndid[3]|idev->rndid[4]|idev->rndid[5]|idev->rndid[6]|idev->rndid[7]) == 0x00)
1980 			goto regen;
1981 	}
1982 }
1983 
1984 static void ipv6_regen_rndid(unsigned long data)
1985 {
1986 	struct inet6_dev *idev = (struct inet6_dev *) data;
1987 	unsigned long expires;
1988 
1989 	rcu_read_lock_bh();
1990 	write_lock_bh(&idev->lock);
1991 
1992 	if (idev->dead)
1993 		goto out;
1994 
1995 	__ipv6_regen_rndid(idev);
1996 
1997 	expires = jiffies +
1998 		idev->cnf.temp_prefered_lft * HZ -
1999 		idev->cnf.regen_max_retry * idev->cnf.dad_transmits *
2000 		NEIGH_VAR(idev->nd_parms, RETRANS_TIME) -
2001 		idev->cnf.max_desync_factor * HZ;
2002 	if (time_before(expires, jiffies)) {
2003 		pr_warn("%s: too short regeneration interval; timer disabled for %s\n",
2004 			__func__, idev->dev->name);
2005 		goto out;
2006 	}
2007 
2008 	if (!mod_timer(&idev->regen_timer, expires))
2009 		in6_dev_hold(idev);
2010 
2011 out:
2012 	write_unlock_bh(&idev->lock);
2013 	rcu_read_unlock_bh();
2014 	in6_dev_put(idev);
2015 }
2016 
2017 static void  __ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr)
2018 {
2019 	if (tmpaddr && memcmp(idev->rndid, &tmpaddr->s6_addr[8], 8) == 0)
2020 		__ipv6_regen_rndid(idev);
2021 }
2022 
2023 /*
2024  *	Add prefix route.
2025  */
2026 
2027 static void
2028 addrconf_prefix_route(struct in6_addr *pfx, int plen, struct net_device *dev,
2029 		      unsigned long expires, u32 flags)
2030 {
2031 	struct fib6_config cfg = {
2032 		.fc_table = RT6_TABLE_PREFIX,
2033 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2034 		.fc_ifindex = dev->ifindex,
2035 		.fc_expires = expires,
2036 		.fc_dst_len = plen,
2037 		.fc_flags = RTF_UP | flags,
2038 		.fc_nlinfo.nl_net = dev_net(dev),
2039 		.fc_protocol = RTPROT_KERNEL,
2040 	};
2041 
2042 	cfg.fc_dst = *pfx;
2043 
2044 	/* Prevent useless cloning on PtP SIT.
2045 	   This thing is done here expecting that the whole
2046 	   class of non-broadcast devices need not cloning.
2047 	 */
2048 #if IS_ENABLED(CONFIG_IPV6_SIT)
2049 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
2050 		cfg.fc_flags |= RTF_NONEXTHOP;
2051 #endif
2052 
2053 	ip6_route_add(&cfg);
2054 }
2055 
2056 
2057 static struct rt6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
2058 						  int plen,
2059 						  const struct net_device *dev,
2060 						  u32 flags, u32 noflags)
2061 {
2062 	struct fib6_node *fn;
2063 	struct rt6_info *rt = NULL;
2064 	struct fib6_table *table;
2065 
2066 	table = fib6_get_table(dev_net(dev), RT6_TABLE_PREFIX);
2067 	if (table == NULL)
2068 		return NULL;
2069 
2070 	read_lock_bh(&table->tb6_lock);
2071 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0);
2072 	if (!fn)
2073 		goto out;
2074 	for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
2075 		if (rt->dst.dev->ifindex != dev->ifindex)
2076 			continue;
2077 		if ((rt->rt6i_flags & flags) != flags)
2078 			continue;
2079 		if ((rt->rt6i_flags & noflags) != 0)
2080 			continue;
2081 		dst_hold(&rt->dst);
2082 		break;
2083 	}
2084 out:
2085 	read_unlock_bh(&table->tb6_lock);
2086 	return rt;
2087 }
2088 
2089 
2090 /* Create "default" multicast route to the interface */
2091 
2092 static void addrconf_add_mroute(struct net_device *dev)
2093 {
2094 	struct fib6_config cfg = {
2095 		.fc_table = RT6_TABLE_LOCAL,
2096 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2097 		.fc_ifindex = dev->ifindex,
2098 		.fc_dst_len = 8,
2099 		.fc_flags = RTF_UP,
2100 		.fc_nlinfo.nl_net = dev_net(dev),
2101 	};
2102 
2103 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
2104 
2105 	ip6_route_add(&cfg);
2106 }
2107 
2108 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2109 {
2110 	struct inet6_dev *idev;
2111 
2112 	ASSERT_RTNL();
2113 
2114 	idev = ipv6_find_idev(dev);
2115 	if (!idev)
2116 		return ERR_PTR(-ENOBUFS);
2117 
2118 	if (idev->cnf.disable_ipv6)
2119 		return ERR_PTR(-EACCES);
2120 
2121 	/* Add default multicast route */
2122 	if (!(dev->flags & IFF_LOOPBACK))
2123 		addrconf_add_mroute(dev);
2124 
2125 	return idev;
2126 }
2127 
2128 static void manage_tempaddrs(struct inet6_dev *idev,
2129 			     struct inet6_ifaddr *ifp,
2130 			     __u32 valid_lft, __u32 prefered_lft,
2131 			     bool create, unsigned long now)
2132 {
2133 	u32 flags;
2134 	struct inet6_ifaddr *ift;
2135 
2136 	read_lock_bh(&idev->lock);
2137 	/* update all temporary addresses in the list */
2138 	list_for_each_entry(ift, &idev->tempaddr_list, tmp_list) {
2139 		int age, max_valid, max_prefered;
2140 
2141 		if (ifp != ift->ifpub)
2142 			continue;
2143 
2144 		/* RFC 4941 section 3.3:
2145 		 * If a received option will extend the lifetime of a public
2146 		 * address, the lifetimes of temporary addresses should
2147 		 * be extended, subject to the overall constraint that no
2148 		 * temporary addresses should ever remain "valid" or "preferred"
2149 		 * for a time longer than (TEMP_VALID_LIFETIME) or
2150 		 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR), respectively.
2151 		 */
2152 		age = (now - ift->cstamp) / HZ;
2153 		max_valid = idev->cnf.temp_valid_lft - age;
2154 		if (max_valid < 0)
2155 			max_valid = 0;
2156 
2157 		max_prefered = idev->cnf.temp_prefered_lft -
2158 			       idev->cnf.max_desync_factor - age;
2159 		if (max_prefered < 0)
2160 			max_prefered = 0;
2161 
2162 		if (valid_lft > max_valid)
2163 			valid_lft = max_valid;
2164 
2165 		if (prefered_lft > max_prefered)
2166 			prefered_lft = max_prefered;
2167 
2168 		spin_lock(&ift->lock);
2169 		flags = ift->flags;
2170 		ift->valid_lft = valid_lft;
2171 		ift->prefered_lft = prefered_lft;
2172 		ift->tstamp = now;
2173 		if (prefered_lft > 0)
2174 			ift->flags &= ~IFA_F_DEPRECATED;
2175 
2176 		spin_unlock(&ift->lock);
2177 		if (!(flags&IFA_F_TENTATIVE))
2178 			ipv6_ifa_notify(0, ift);
2179 	}
2180 
2181 	if ((create || list_empty(&idev->tempaddr_list)) &&
2182 	    idev->cnf.use_tempaddr > 0) {
2183 		/* When a new public address is created as described
2184 		 * in [ADDRCONF], also create a new temporary address.
2185 		 * Also create a temporary address if it's enabled but
2186 		 * no temporary address currently exists.
2187 		 */
2188 		read_unlock_bh(&idev->lock);
2189 		ipv6_create_tempaddr(ifp, NULL);
2190 	} else {
2191 		read_unlock_bh(&idev->lock);
2192 	}
2193 }
2194 
2195 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2196 {
2197 	struct prefix_info *pinfo;
2198 	__u32 valid_lft;
2199 	__u32 prefered_lft;
2200 	int addr_type;
2201 	u32 addr_flags = 0;
2202 	struct inet6_dev *in6_dev;
2203 	struct net *net = dev_net(dev);
2204 
2205 	pinfo = (struct prefix_info *) opt;
2206 
2207 	if (len < sizeof(struct prefix_info)) {
2208 		ADBG("addrconf: prefix option too short\n");
2209 		return;
2210 	}
2211 
2212 	/*
2213 	 *	Validation checks ([ADDRCONF], page 19)
2214 	 */
2215 
2216 	addr_type = ipv6_addr_type(&pinfo->prefix);
2217 
2218 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2219 		return;
2220 
2221 	valid_lft = ntohl(pinfo->valid);
2222 	prefered_lft = ntohl(pinfo->prefered);
2223 
2224 	if (prefered_lft > valid_lft) {
2225 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2226 		return;
2227 	}
2228 
2229 	in6_dev = in6_dev_get(dev);
2230 
2231 	if (in6_dev == NULL) {
2232 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2233 				    dev->name);
2234 		return;
2235 	}
2236 
2237 	/*
2238 	 *	Two things going on here:
2239 	 *	1) Add routes for on-link prefixes
2240 	 *	2) Configure prefixes with the auto flag set
2241 	 */
2242 
2243 	if (pinfo->onlink) {
2244 		struct rt6_info *rt;
2245 		unsigned long rt_expires;
2246 
2247 		/* Avoid arithmetic overflow. Really, we could
2248 		 * save rt_expires in seconds, likely valid_lft,
2249 		 * but it would require division in fib gc, that it
2250 		 * not good.
2251 		 */
2252 		if (HZ > USER_HZ)
2253 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2254 		else
2255 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2256 
2257 		if (addrconf_finite_timeout(rt_expires))
2258 			rt_expires *= HZ;
2259 
2260 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2261 					       pinfo->prefix_len,
2262 					       dev,
2263 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2264 					       RTF_GATEWAY | RTF_DEFAULT);
2265 
2266 		if (rt) {
2267 			/* Autoconf prefix route */
2268 			if (valid_lft == 0) {
2269 				ip6_del_rt(rt);
2270 				rt = NULL;
2271 			} else if (addrconf_finite_timeout(rt_expires)) {
2272 				/* not infinity */
2273 				rt6_set_expires(rt, jiffies + rt_expires);
2274 			} else {
2275 				rt6_clean_expires(rt);
2276 			}
2277 		} else if (valid_lft) {
2278 			clock_t expires = 0;
2279 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2280 			if (addrconf_finite_timeout(rt_expires)) {
2281 				/* not infinity */
2282 				flags |= RTF_EXPIRES;
2283 				expires = jiffies_to_clock_t(rt_expires);
2284 			}
2285 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2286 					      dev, expires, flags);
2287 		}
2288 		ip6_rt_put(rt);
2289 	}
2290 
2291 	/* Try to figure out our local address for this prefix */
2292 
2293 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
2294 		struct inet6_ifaddr *ifp;
2295 		struct in6_addr addr;
2296 		int create = 0, update_lft = 0;
2297 		bool tokenized = false;
2298 
2299 		if (pinfo->prefix_len == 64) {
2300 			memcpy(&addr, &pinfo->prefix, 8);
2301 
2302 			if (!ipv6_addr_any(&in6_dev->token)) {
2303 				read_lock_bh(&in6_dev->lock);
2304 				memcpy(addr.s6_addr + 8,
2305 				       in6_dev->token.s6_addr + 8, 8);
2306 				read_unlock_bh(&in6_dev->lock);
2307 				tokenized = true;
2308 			} else if (in6_dev->addr_gen_mode ==
2309 				   IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
2310 				   !ipv6_generate_stable_address(&addr, 0,
2311 								 in6_dev)) {
2312 				addr_flags |= IFA_F_STABLE_PRIVACY;
2313 				goto ok;
2314 			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2315 				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2316 				in6_dev_put(in6_dev);
2317 				return;
2318 			}
2319 			goto ok;
2320 		}
2321 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2322 				    pinfo->prefix_len);
2323 		in6_dev_put(in6_dev);
2324 		return;
2325 
2326 ok:
2327 
2328 		ifp = ipv6_get_ifaddr(net, &addr, dev, 1);
2329 
2330 		if (ifp == NULL && valid_lft) {
2331 			int max_addresses = in6_dev->cnf.max_addresses;
2332 
2333 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2334 			if (in6_dev->cnf.optimistic_dad &&
2335 			    !net->ipv6.devconf_all->forwarding && sllao)
2336 				addr_flags = IFA_F_OPTIMISTIC;
2337 #endif
2338 
2339 			/* Do not allow to create too much of autoconfigured
2340 			 * addresses; this would be too easy way to crash kernel.
2341 			 */
2342 			if (!max_addresses ||
2343 			    ipv6_count_addresses(in6_dev) < max_addresses)
2344 				ifp = ipv6_add_addr(in6_dev, &addr, NULL,
2345 						    pinfo->prefix_len,
2346 						    addr_type&IPV6_ADDR_SCOPE_MASK,
2347 						    addr_flags, valid_lft,
2348 						    prefered_lft);
2349 
2350 			if (IS_ERR_OR_NULL(ifp)) {
2351 				in6_dev_put(in6_dev);
2352 				return;
2353 			}
2354 
2355 			update_lft = 0;
2356 			create = 1;
2357 			spin_lock_bh(&ifp->lock);
2358 			ifp->flags |= IFA_F_MANAGETEMPADDR;
2359 			ifp->cstamp = jiffies;
2360 			ifp->tokenized = tokenized;
2361 			spin_unlock_bh(&ifp->lock);
2362 			addrconf_dad_start(ifp);
2363 		}
2364 
2365 		if (ifp) {
2366 			u32 flags;
2367 			unsigned long now;
2368 			u32 stored_lft;
2369 
2370 			/* update lifetime (RFC2462 5.5.3 e) */
2371 			spin_lock_bh(&ifp->lock);
2372 			now = jiffies;
2373 			if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2374 				stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2375 			else
2376 				stored_lft = 0;
2377 			if (!update_lft && !create && stored_lft) {
2378 				const u32 minimum_lft = min_t(u32,
2379 					stored_lft, MIN_VALID_LIFETIME);
2380 				valid_lft = max(valid_lft, minimum_lft);
2381 
2382 				/* RFC4862 Section 5.5.3e:
2383 				 * "Note that the preferred lifetime of the
2384 				 *  corresponding address is always reset to
2385 				 *  the Preferred Lifetime in the received
2386 				 *  Prefix Information option, regardless of
2387 				 *  whether the valid lifetime is also reset or
2388 				 *  ignored."
2389 				 *
2390 				 * So we should always update prefered_lft here.
2391 				 */
2392 				update_lft = 1;
2393 			}
2394 
2395 			if (update_lft) {
2396 				ifp->valid_lft = valid_lft;
2397 				ifp->prefered_lft = prefered_lft;
2398 				ifp->tstamp = now;
2399 				flags = ifp->flags;
2400 				ifp->flags &= ~IFA_F_DEPRECATED;
2401 				spin_unlock_bh(&ifp->lock);
2402 
2403 				if (!(flags&IFA_F_TENTATIVE))
2404 					ipv6_ifa_notify(0, ifp);
2405 			} else
2406 				spin_unlock_bh(&ifp->lock);
2407 
2408 			manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
2409 					 create, now);
2410 
2411 			in6_ifa_put(ifp);
2412 			addrconf_verify();
2413 		}
2414 	}
2415 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2416 	in6_dev_put(in6_dev);
2417 }
2418 
2419 /*
2420  *	Set destination address.
2421  *	Special case for SIT interfaces where we create a new "virtual"
2422  *	device.
2423  */
2424 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2425 {
2426 	struct in6_ifreq ireq;
2427 	struct net_device *dev;
2428 	int err = -EINVAL;
2429 
2430 	rtnl_lock();
2431 
2432 	err = -EFAULT;
2433 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2434 		goto err_exit;
2435 
2436 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2437 
2438 	err = -ENODEV;
2439 	if (dev == NULL)
2440 		goto err_exit;
2441 
2442 #if IS_ENABLED(CONFIG_IPV6_SIT)
2443 	if (dev->type == ARPHRD_SIT) {
2444 		const struct net_device_ops *ops = dev->netdev_ops;
2445 		struct ifreq ifr;
2446 		struct ip_tunnel_parm p;
2447 
2448 		err = -EADDRNOTAVAIL;
2449 		if (!(ipv6_addr_type(&ireq.ifr6_addr) & IPV6_ADDR_COMPATv4))
2450 			goto err_exit;
2451 
2452 		memset(&p, 0, sizeof(p));
2453 		p.iph.daddr = ireq.ifr6_addr.s6_addr32[3];
2454 		p.iph.saddr = 0;
2455 		p.iph.version = 4;
2456 		p.iph.ihl = 5;
2457 		p.iph.protocol = IPPROTO_IPV6;
2458 		p.iph.ttl = 64;
2459 		ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
2460 
2461 		if (ops->ndo_do_ioctl) {
2462 			mm_segment_t oldfs = get_fs();
2463 
2464 			set_fs(KERNEL_DS);
2465 			err = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
2466 			set_fs(oldfs);
2467 		} else
2468 			err = -EOPNOTSUPP;
2469 
2470 		if (err == 0) {
2471 			err = -ENOBUFS;
2472 			dev = __dev_get_by_name(net, p.name);
2473 			if (!dev)
2474 				goto err_exit;
2475 			err = dev_open(dev);
2476 		}
2477 	}
2478 #endif
2479 
2480 err_exit:
2481 	rtnl_unlock();
2482 	return err;
2483 }
2484 
2485 static int ipv6_mc_config(struct sock *sk, bool join,
2486 			  const struct in6_addr *addr, int ifindex)
2487 {
2488 	int ret;
2489 
2490 	ASSERT_RTNL();
2491 
2492 	lock_sock(sk);
2493 	if (join)
2494 		ret = ipv6_sock_mc_join(sk, ifindex, addr);
2495 	else
2496 		ret = ipv6_sock_mc_drop(sk, ifindex, addr);
2497 	release_sock(sk);
2498 
2499 	return ret;
2500 }
2501 
2502 /*
2503  *	Manual configuration of address on an interface
2504  */
2505 static int inet6_addr_add(struct net *net, int ifindex,
2506 			  const struct in6_addr *pfx,
2507 			  const struct in6_addr *peer_pfx,
2508 			  unsigned int plen, __u32 ifa_flags,
2509 			  __u32 prefered_lft, __u32 valid_lft)
2510 {
2511 	struct inet6_ifaddr *ifp;
2512 	struct inet6_dev *idev;
2513 	struct net_device *dev;
2514 	unsigned long timeout;
2515 	clock_t expires;
2516 	int scope;
2517 	u32 flags;
2518 
2519 	ASSERT_RTNL();
2520 
2521 	if (plen > 128)
2522 		return -EINVAL;
2523 
2524 	/* check the lifetime */
2525 	if (!valid_lft || prefered_lft > valid_lft)
2526 		return -EINVAL;
2527 
2528 	if (ifa_flags & IFA_F_MANAGETEMPADDR && plen != 64)
2529 		return -EINVAL;
2530 
2531 	dev = __dev_get_by_index(net, ifindex);
2532 	if (!dev)
2533 		return -ENODEV;
2534 
2535 	idev = addrconf_add_dev(dev);
2536 	if (IS_ERR(idev))
2537 		return PTR_ERR(idev);
2538 
2539 	if (ifa_flags & IFA_F_MCAUTOJOIN) {
2540 		int ret = ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2541 					 true, pfx, ifindex);
2542 
2543 		if (ret < 0)
2544 			return ret;
2545 	}
2546 
2547 	scope = ipv6_addr_scope(pfx);
2548 
2549 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
2550 	if (addrconf_finite_timeout(timeout)) {
2551 		expires = jiffies_to_clock_t(timeout * HZ);
2552 		valid_lft = timeout;
2553 		flags = RTF_EXPIRES;
2554 	} else {
2555 		expires = 0;
2556 		flags = 0;
2557 		ifa_flags |= IFA_F_PERMANENT;
2558 	}
2559 
2560 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
2561 	if (addrconf_finite_timeout(timeout)) {
2562 		if (timeout == 0)
2563 			ifa_flags |= IFA_F_DEPRECATED;
2564 		prefered_lft = timeout;
2565 	}
2566 
2567 	ifp = ipv6_add_addr(idev, pfx, peer_pfx, plen, scope, ifa_flags,
2568 			    valid_lft, prefered_lft);
2569 
2570 	if (!IS_ERR(ifp)) {
2571 		if (!(ifa_flags & IFA_F_NOPREFIXROUTE)) {
2572 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len, dev,
2573 					      expires, flags);
2574 		}
2575 
2576 		/*
2577 		 * Note that section 3.1 of RFC 4429 indicates
2578 		 * that the Optimistic flag should not be set for
2579 		 * manually configured addresses
2580 		 */
2581 		addrconf_dad_start(ifp);
2582 		if (ifa_flags & IFA_F_MANAGETEMPADDR)
2583 			manage_tempaddrs(idev, ifp, valid_lft, prefered_lft,
2584 					 true, jiffies);
2585 		in6_ifa_put(ifp);
2586 		addrconf_verify_rtnl();
2587 		return 0;
2588 	} else if (ifa_flags & IFA_F_MCAUTOJOIN) {
2589 		ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2590 			       false, pfx, ifindex);
2591 	}
2592 
2593 	return PTR_ERR(ifp);
2594 }
2595 
2596 static int inet6_addr_del(struct net *net, int ifindex, u32 ifa_flags,
2597 			  const struct in6_addr *pfx, unsigned int plen)
2598 {
2599 	struct inet6_ifaddr *ifp;
2600 	struct inet6_dev *idev;
2601 	struct net_device *dev;
2602 
2603 	if (plen > 128)
2604 		return -EINVAL;
2605 
2606 	dev = __dev_get_by_index(net, ifindex);
2607 	if (!dev)
2608 		return -ENODEV;
2609 
2610 	idev = __in6_dev_get(dev);
2611 	if (idev == NULL)
2612 		return -ENXIO;
2613 
2614 	read_lock_bh(&idev->lock);
2615 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
2616 		if (ifp->prefix_len == plen &&
2617 		    ipv6_addr_equal(pfx, &ifp->addr)) {
2618 			in6_ifa_hold(ifp);
2619 			read_unlock_bh(&idev->lock);
2620 
2621 			if (!(ifp->flags & IFA_F_TEMPORARY) &&
2622 			    (ifa_flags & IFA_F_MANAGETEMPADDR))
2623 				manage_tempaddrs(idev, ifp, 0, 0, false,
2624 						 jiffies);
2625 			ipv6_del_addr(ifp);
2626 			addrconf_verify_rtnl();
2627 			if (ipv6_addr_is_multicast(pfx)) {
2628 				ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2629 					       false, pfx, dev->ifindex);
2630 			}
2631 			return 0;
2632 		}
2633 	}
2634 	read_unlock_bh(&idev->lock);
2635 	return -EADDRNOTAVAIL;
2636 }
2637 
2638 
2639 int addrconf_add_ifaddr(struct net *net, void __user *arg)
2640 {
2641 	struct in6_ifreq ireq;
2642 	int err;
2643 
2644 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2645 		return -EPERM;
2646 
2647 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2648 		return -EFAULT;
2649 
2650 	rtnl_lock();
2651 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &ireq.ifr6_addr, NULL,
2652 			     ireq.ifr6_prefixlen, IFA_F_PERMANENT,
2653 			     INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
2654 	rtnl_unlock();
2655 	return err;
2656 }
2657 
2658 int addrconf_del_ifaddr(struct net *net, void __user *arg)
2659 {
2660 	struct in6_ifreq ireq;
2661 	int err;
2662 
2663 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2664 		return -EPERM;
2665 
2666 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2667 		return -EFAULT;
2668 
2669 	rtnl_lock();
2670 	err = inet6_addr_del(net, ireq.ifr6_ifindex, 0, &ireq.ifr6_addr,
2671 			     ireq.ifr6_prefixlen);
2672 	rtnl_unlock();
2673 	return err;
2674 }
2675 
2676 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
2677 		     int plen, int scope)
2678 {
2679 	struct inet6_ifaddr *ifp;
2680 
2681 	ifp = ipv6_add_addr(idev, addr, NULL, plen,
2682 			    scope, IFA_F_PERMANENT,
2683 			    INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
2684 	if (!IS_ERR(ifp)) {
2685 		spin_lock_bh(&ifp->lock);
2686 		ifp->flags &= ~IFA_F_TENTATIVE;
2687 		spin_unlock_bh(&ifp->lock);
2688 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
2689 		in6_ifa_put(ifp);
2690 	}
2691 }
2692 
2693 #if IS_ENABLED(CONFIG_IPV6_SIT)
2694 static void sit_add_v4_addrs(struct inet6_dev *idev)
2695 {
2696 	struct in6_addr addr;
2697 	struct net_device *dev;
2698 	struct net *net = dev_net(idev->dev);
2699 	int scope, plen;
2700 	u32 pflags = 0;
2701 
2702 	ASSERT_RTNL();
2703 
2704 	memset(&addr, 0, sizeof(struct in6_addr));
2705 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
2706 
2707 	if (idev->dev->flags&IFF_POINTOPOINT) {
2708 		addr.s6_addr32[0] = htonl(0xfe800000);
2709 		scope = IFA_LINK;
2710 		plen = 64;
2711 	} else {
2712 		scope = IPV6_ADDR_COMPATv4;
2713 		plen = 96;
2714 		pflags |= RTF_NONEXTHOP;
2715 	}
2716 
2717 	if (addr.s6_addr32[3]) {
2718 		add_addr(idev, &addr, plen, scope);
2719 		addrconf_prefix_route(&addr, plen, idev->dev, 0, pflags);
2720 		return;
2721 	}
2722 
2723 	for_each_netdev(net, dev) {
2724 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
2725 		if (in_dev && (dev->flags & IFF_UP)) {
2726 			struct in_ifaddr *ifa;
2727 
2728 			int flag = scope;
2729 
2730 			for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
2731 
2732 				addr.s6_addr32[3] = ifa->ifa_local;
2733 
2734 				if (ifa->ifa_scope == RT_SCOPE_LINK)
2735 					continue;
2736 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
2737 					if (idev->dev->flags&IFF_POINTOPOINT)
2738 						continue;
2739 					flag |= IFA_HOST;
2740 				}
2741 
2742 				add_addr(idev, &addr, plen, flag);
2743 				addrconf_prefix_route(&addr, plen, idev->dev, 0,
2744 						      pflags);
2745 			}
2746 		}
2747 	}
2748 }
2749 #endif
2750 
2751 static void init_loopback(struct net_device *dev)
2752 {
2753 	struct inet6_dev  *idev;
2754 	struct net_device *sp_dev;
2755 	struct inet6_ifaddr *sp_ifa;
2756 	struct rt6_info *sp_rt;
2757 
2758 	/* ::1 */
2759 
2760 	ASSERT_RTNL();
2761 
2762 	idev = ipv6_find_idev(dev);
2763 	if (idev == NULL) {
2764 		pr_debug("%s: add_dev failed\n", __func__);
2765 		return;
2766 	}
2767 
2768 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST);
2769 
2770 	/* Add routes to other interface's IPv6 addresses */
2771 	for_each_netdev(dev_net(dev), sp_dev) {
2772 		if (!strcmp(sp_dev->name, dev->name))
2773 			continue;
2774 
2775 		idev = __in6_dev_get(sp_dev);
2776 		if (!idev)
2777 			continue;
2778 
2779 		read_lock_bh(&idev->lock);
2780 		list_for_each_entry(sp_ifa, &idev->addr_list, if_list) {
2781 
2782 			if (sp_ifa->flags & (IFA_F_DADFAILED | IFA_F_TENTATIVE))
2783 				continue;
2784 
2785 			if (sp_ifa->rt) {
2786 				/* This dst has been added to garbage list when
2787 				 * lo device down, release this obsolete dst and
2788 				 * reallocate a new router for ifa.
2789 				 */
2790 				if (sp_ifa->rt->dst.obsolete > 0) {
2791 					ip6_rt_put(sp_ifa->rt);
2792 					sp_ifa->rt = NULL;
2793 				} else {
2794 					continue;
2795 				}
2796 			}
2797 
2798 			sp_rt = addrconf_dst_alloc(idev, &sp_ifa->addr, false);
2799 
2800 			/* Failure cases are ignored */
2801 			if (!IS_ERR(sp_rt)) {
2802 				sp_ifa->rt = sp_rt;
2803 				ip6_ins_rt(sp_rt);
2804 			}
2805 		}
2806 		read_unlock_bh(&idev->lock);
2807 	}
2808 }
2809 
2810 static void addrconf_add_linklocal(struct inet6_dev *idev,
2811 				   const struct in6_addr *addr, u32 flags)
2812 {
2813 	struct inet6_ifaddr *ifp;
2814 	u32 addr_flags = flags | IFA_F_PERMANENT;
2815 
2816 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2817 	if (idev->cnf.optimistic_dad &&
2818 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
2819 		addr_flags |= IFA_F_OPTIMISTIC;
2820 #endif
2821 
2822 	ifp = ipv6_add_addr(idev, addr, NULL, 64, IFA_LINK, addr_flags,
2823 			    INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
2824 	if (!IS_ERR(ifp)) {
2825 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, idev->dev, 0, 0);
2826 		addrconf_dad_start(ifp);
2827 		in6_ifa_put(ifp);
2828 	}
2829 }
2830 
2831 static bool ipv6_reserved_interfaceid(struct in6_addr address)
2832 {
2833 	if ((address.s6_addr32[2] | address.s6_addr32[3]) == 0)
2834 		return true;
2835 
2836 	if (address.s6_addr32[2] == htonl(0x02005eff) &&
2837 	    ((address.s6_addr32[3] & htonl(0xfe000000)) == htonl(0xfe000000)))
2838 		return true;
2839 
2840 	if (address.s6_addr32[2] == htonl(0xfdffffff) &&
2841 	    ((address.s6_addr32[3] & htonl(0xffffff80)) == htonl(0xffffff80)))
2842 		return true;
2843 
2844 	return false;
2845 }
2846 
2847 static int ipv6_generate_stable_address(struct in6_addr *address,
2848 					u8 dad_count,
2849 					const struct inet6_dev *idev)
2850 {
2851 	static const int idgen_retries = 3;
2852 
2853 	static DEFINE_SPINLOCK(lock);
2854 	static __u32 digest[SHA_DIGEST_WORDS];
2855 	static __u32 workspace[SHA_WORKSPACE_WORDS];
2856 
2857 	static union {
2858 		char __data[SHA_MESSAGE_BYTES];
2859 		struct {
2860 			struct in6_addr secret;
2861 			__be64 prefix;
2862 			unsigned char hwaddr[MAX_ADDR_LEN];
2863 			u8 dad_count;
2864 		} __packed;
2865 	} data;
2866 
2867 	struct in6_addr secret;
2868 	struct in6_addr temp;
2869 	struct net *net = dev_net(idev->dev);
2870 
2871 	BUILD_BUG_ON(sizeof(data.__data) != sizeof(data));
2872 
2873 	if (idev->cnf.stable_secret.initialized)
2874 		secret = idev->cnf.stable_secret.secret;
2875 	else if (net->ipv6.devconf_dflt->stable_secret.initialized)
2876 		secret = net->ipv6.devconf_dflt->stable_secret.secret;
2877 	else
2878 		return -1;
2879 
2880 retry:
2881 	spin_lock_bh(&lock);
2882 
2883 	sha_init(digest);
2884 	memset(&data, 0, sizeof(data));
2885 	memset(workspace, 0, sizeof(workspace));
2886 	memcpy(data.hwaddr, idev->dev->perm_addr, idev->dev->addr_len);
2887 	data.prefix = ((__be64)address->s6_addr32[0] << 32) |
2888 		       (__be64)address->s6_addr32[1];
2889 	data.secret = secret;
2890 	data.dad_count = dad_count;
2891 
2892 	sha_transform(digest, data.__data, workspace);
2893 
2894 	temp = *address;
2895 	temp.s6_addr32[2] = digest[0];
2896 	temp.s6_addr32[3] = digest[1];
2897 
2898 	spin_unlock_bh(&lock);
2899 
2900 	if (ipv6_reserved_interfaceid(temp)) {
2901 		dad_count++;
2902 		if (dad_count > idgen_retries)
2903 			return -1;
2904 		goto retry;
2905 	}
2906 
2907 	*address = temp;
2908 	return 0;
2909 }
2910 
2911 static void addrconf_addr_gen(struct inet6_dev *idev, bool prefix_route)
2912 {
2913 	struct in6_addr addr;
2914 
2915 	ipv6_addr_set(&addr, htonl(0xFE800000), 0, 0, 0);
2916 
2917 	if (idev->addr_gen_mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY) {
2918 		if (!ipv6_generate_stable_address(&addr, 0, idev))
2919 			addrconf_add_linklocal(idev, &addr,
2920 					       IFA_F_STABLE_PRIVACY);
2921 		else if (prefix_route)
2922 			addrconf_prefix_route(&addr, 64, idev->dev, 0, 0);
2923 	} else if (idev->addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64) {
2924 		/* addrconf_add_linklocal also adds a prefix_route and we
2925 		 * only need to care about prefix routes if ipv6_generate_eui64
2926 		 * couldn't generate one.
2927 		 */
2928 		if (ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) == 0)
2929 			addrconf_add_linklocal(idev, &addr, 0);
2930 		else if (prefix_route)
2931 			addrconf_prefix_route(&addr, 64, idev->dev, 0, 0);
2932 	}
2933 }
2934 
2935 static void addrconf_dev_config(struct net_device *dev)
2936 {
2937 	struct inet6_dev *idev;
2938 
2939 	ASSERT_RTNL();
2940 
2941 	if ((dev->type != ARPHRD_ETHER) &&
2942 	    (dev->type != ARPHRD_FDDI) &&
2943 	    (dev->type != ARPHRD_ARCNET) &&
2944 	    (dev->type != ARPHRD_INFINIBAND) &&
2945 	    (dev->type != ARPHRD_IEEE802154) &&
2946 	    (dev->type != ARPHRD_IEEE1394) &&
2947 	    (dev->type != ARPHRD_TUNNEL6) &&
2948 	    (dev->type != ARPHRD_6LOWPAN)) {
2949 		/* Alas, we support only Ethernet autoconfiguration. */
2950 		return;
2951 	}
2952 
2953 	idev = addrconf_add_dev(dev);
2954 	if (IS_ERR(idev))
2955 		return;
2956 
2957 	addrconf_addr_gen(idev, false);
2958 }
2959 
2960 #if IS_ENABLED(CONFIG_IPV6_SIT)
2961 static void addrconf_sit_config(struct net_device *dev)
2962 {
2963 	struct inet6_dev *idev;
2964 
2965 	ASSERT_RTNL();
2966 
2967 	/*
2968 	 * Configure the tunnel with one of our IPv4
2969 	 * addresses... we should configure all of
2970 	 * our v4 addrs in the tunnel
2971 	 */
2972 
2973 	idev = ipv6_find_idev(dev);
2974 	if (idev == NULL) {
2975 		pr_debug("%s: add_dev failed\n", __func__);
2976 		return;
2977 	}
2978 
2979 	if (dev->priv_flags & IFF_ISATAP) {
2980 		addrconf_addr_gen(idev, false);
2981 		return;
2982 	}
2983 
2984 	sit_add_v4_addrs(idev);
2985 
2986 	if (dev->flags&IFF_POINTOPOINT)
2987 		addrconf_add_mroute(dev);
2988 }
2989 #endif
2990 
2991 #if IS_ENABLED(CONFIG_NET_IPGRE)
2992 static void addrconf_gre_config(struct net_device *dev)
2993 {
2994 	struct inet6_dev *idev;
2995 
2996 	ASSERT_RTNL();
2997 
2998 	idev = ipv6_find_idev(dev);
2999 	if (idev == NULL) {
3000 		pr_debug("%s: add_dev failed\n", __func__);
3001 		return;
3002 	}
3003 
3004 	addrconf_addr_gen(idev, true);
3005 }
3006 #endif
3007 
3008 static int addrconf_notify(struct notifier_block *this, unsigned long event,
3009 			   void *ptr)
3010 {
3011 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3012 	struct inet6_dev *idev = __in6_dev_get(dev);
3013 	int run_pending = 0;
3014 	int err;
3015 
3016 	switch (event) {
3017 	case NETDEV_REGISTER:
3018 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
3019 			idev = ipv6_add_dev(dev);
3020 			if (IS_ERR(idev))
3021 				return notifier_from_errno(PTR_ERR(idev));
3022 		}
3023 		break;
3024 
3025 	case NETDEV_UP:
3026 	case NETDEV_CHANGE:
3027 		if (dev->flags & IFF_SLAVE)
3028 			break;
3029 
3030 		if (idev && idev->cnf.disable_ipv6)
3031 			break;
3032 
3033 		if (event == NETDEV_UP) {
3034 			if (!addrconf_qdisc_ok(dev)) {
3035 				/* device is not ready yet. */
3036 				pr_info("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
3037 					dev->name);
3038 				break;
3039 			}
3040 
3041 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
3042 				idev = ipv6_add_dev(dev);
3043 
3044 			if (!IS_ERR_OR_NULL(idev)) {
3045 				idev->if_flags |= IF_READY;
3046 				run_pending = 1;
3047 			}
3048 		} else {
3049 			if (!addrconf_qdisc_ok(dev)) {
3050 				/* device is still not ready. */
3051 				break;
3052 			}
3053 
3054 			if (idev) {
3055 				if (idev->if_flags & IF_READY)
3056 					/* device is already configured. */
3057 					break;
3058 				idev->if_flags |= IF_READY;
3059 			}
3060 
3061 			pr_info("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
3062 				dev->name);
3063 
3064 			run_pending = 1;
3065 		}
3066 
3067 		switch (dev->type) {
3068 #if IS_ENABLED(CONFIG_IPV6_SIT)
3069 		case ARPHRD_SIT:
3070 			addrconf_sit_config(dev);
3071 			break;
3072 #endif
3073 #if IS_ENABLED(CONFIG_NET_IPGRE)
3074 		case ARPHRD_IPGRE:
3075 			addrconf_gre_config(dev);
3076 			break;
3077 #endif
3078 		case ARPHRD_LOOPBACK:
3079 			init_loopback(dev);
3080 			break;
3081 
3082 		default:
3083 			addrconf_dev_config(dev);
3084 			break;
3085 		}
3086 
3087 		if (!IS_ERR_OR_NULL(idev)) {
3088 			if (run_pending)
3089 				addrconf_dad_run(idev);
3090 
3091 			/*
3092 			 * If the MTU changed during the interface down,
3093 			 * when the interface up, the changed MTU must be
3094 			 * reflected in the idev as well as routers.
3095 			 */
3096 			if (idev->cnf.mtu6 != dev->mtu &&
3097 			    dev->mtu >= IPV6_MIN_MTU) {
3098 				rt6_mtu_change(dev, dev->mtu);
3099 				idev->cnf.mtu6 = dev->mtu;
3100 			}
3101 			idev->tstamp = jiffies;
3102 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
3103 
3104 			/*
3105 			 * If the changed mtu during down is lower than
3106 			 * IPV6_MIN_MTU stop IPv6 on this interface.
3107 			 */
3108 			if (dev->mtu < IPV6_MIN_MTU)
3109 				addrconf_ifdown(dev, 1);
3110 		}
3111 		break;
3112 
3113 	case NETDEV_CHANGEMTU:
3114 		if (idev && dev->mtu >= IPV6_MIN_MTU) {
3115 			rt6_mtu_change(dev, dev->mtu);
3116 			idev->cnf.mtu6 = dev->mtu;
3117 			break;
3118 		}
3119 
3120 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
3121 			idev = ipv6_add_dev(dev);
3122 			if (!IS_ERR(idev))
3123 				break;
3124 		}
3125 
3126 		/*
3127 		 * if MTU under IPV6_MIN_MTU.
3128 		 * Stop IPv6 on this interface.
3129 		 */
3130 
3131 	case NETDEV_DOWN:
3132 	case NETDEV_UNREGISTER:
3133 		/*
3134 		 *	Remove all addresses from this interface.
3135 		 */
3136 		addrconf_ifdown(dev, event != NETDEV_DOWN);
3137 		break;
3138 
3139 	case NETDEV_CHANGENAME:
3140 		if (idev) {
3141 			snmp6_unregister_dev(idev);
3142 			addrconf_sysctl_unregister(idev);
3143 			err = addrconf_sysctl_register(idev);
3144 			if (err)
3145 				return notifier_from_errno(err);
3146 			err = snmp6_register_dev(idev);
3147 			if (err) {
3148 				addrconf_sysctl_unregister(idev);
3149 				return notifier_from_errno(err);
3150 			}
3151 		}
3152 		break;
3153 
3154 	case NETDEV_PRE_TYPE_CHANGE:
3155 	case NETDEV_POST_TYPE_CHANGE:
3156 		addrconf_type_change(dev, event);
3157 		break;
3158 	}
3159 
3160 	return NOTIFY_OK;
3161 }
3162 
3163 /*
3164  *	addrconf module should be notified of a device going up
3165  */
3166 static struct notifier_block ipv6_dev_notf = {
3167 	.notifier_call = addrconf_notify,
3168 };
3169 
3170 static void addrconf_type_change(struct net_device *dev, unsigned long event)
3171 {
3172 	struct inet6_dev *idev;
3173 	ASSERT_RTNL();
3174 
3175 	idev = __in6_dev_get(dev);
3176 
3177 	if (event == NETDEV_POST_TYPE_CHANGE)
3178 		ipv6_mc_remap(idev);
3179 	else if (event == NETDEV_PRE_TYPE_CHANGE)
3180 		ipv6_mc_unmap(idev);
3181 }
3182 
3183 static int addrconf_ifdown(struct net_device *dev, int how)
3184 {
3185 	struct net *net = dev_net(dev);
3186 	struct inet6_dev *idev;
3187 	struct inet6_ifaddr *ifa;
3188 	int state, i;
3189 
3190 	ASSERT_RTNL();
3191 
3192 	rt6_ifdown(net, dev);
3193 	neigh_ifdown(&nd_tbl, dev);
3194 
3195 	idev = __in6_dev_get(dev);
3196 	if (idev == NULL)
3197 		return -ENODEV;
3198 
3199 	/*
3200 	 * Step 1: remove reference to ipv6 device from parent device.
3201 	 *	   Do not dev_put!
3202 	 */
3203 	if (how) {
3204 		idev->dead = 1;
3205 
3206 		/* protected by rtnl_lock */
3207 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
3208 
3209 		/* Step 1.5: remove snmp6 entry */
3210 		snmp6_unregister_dev(idev);
3211 
3212 	}
3213 
3214 	/* Step 2: clear hash table */
3215 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3216 		struct hlist_head *h = &inet6_addr_lst[i];
3217 
3218 		spin_lock_bh(&addrconf_hash_lock);
3219 restart:
3220 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
3221 			if (ifa->idev == idev) {
3222 				hlist_del_init_rcu(&ifa->addr_lst);
3223 				addrconf_del_dad_work(ifa);
3224 				goto restart;
3225 			}
3226 		}
3227 		spin_unlock_bh(&addrconf_hash_lock);
3228 	}
3229 
3230 	write_lock_bh(&idev->lock);
3231 
3232 	addrconf_del_rs_timer(idev);
3233 
3234 	/* Step 2: clear flags for stateless addrconf */
3235 	if (!how)
3236 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3237 
3238 	if (how && del_timer(&idev->regen_timer))
3239 		in6_dev_put(idev);
3240 
3241 	/* Step 3: clear tempaddr list */
3242 	while (!list_empty(&idev->tempaddr_list)) {
3243 		ifa = list_first_entry(&idev->tempaddr_list,
3244 				       struct inet6_ifaddr, tmp_list);
3245 		list_del(&ifa->tmp_list);
3246 		write_unlock_bh(&idev->lock);
3247 		spin_lock_bh(&ifa->lock);
3248 
3249 		if (ifa->ifpub) {
3250 			in6_ifa_put(ifa->ifpub);
3251 			ifa->ifpub = NULL;
3252 		}
3253 		spin_unlock_bh(&ifa->lock);
3254 		in6_ifa_put(ifa);
3255 		write_lock_bh(&idev->lock);
3256 	}
3257 
3258 	while (!list_empty(&idev->addr_list)) {
3259 		ifa = list_first_entry(&idev->addr_list,
3260 				       struct inet6_ifaddr, if_list);
3261 		addrconf_del_dad_work(ifa);
3262 
3263 		list_del(&ifa->if_list);
3264 
3265 		write_unlock_bh(&idev->lock);
3266 
3267 		spin_lock_bh(&ifa->lock);
3268 		state = ifa->state;
3269 		ifa->state = INET6_IFADDR_STATE_DEAD;
3270 		spin_unlock_bh(&ifa->lock);
3271 
3272 		if (state != INET6_IFADDR_STATE_DEAD) {
3273 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
3274 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
3275 		}
3276 		in6_ifa_put(ifa);
3277 
3278 		write_lock_bh(&idev->lock);
3279 	}
3280 
3281 	write_unlock_bh(&idev->lock);
3282 
3283 	/* Step 5: Discard anycast and multicast list */
3284 	if (how) {
3285 		ipv6_ac_destroy_dev(idev);
3286 		ipv6_mc_destroy_dev(idev);
3287 	} else {
3288 		ipv6_mc_down(idev);
3289 	}
3290 
3291 	idev->tstamp = jiffies;
3292 
3293 	/* Last: Shot the device (if unregistered) */
3294 	if (how) {
3295 		addrconf_sysctl_unregister(idev);
3296 		neigh_parms_release(&nd_tbl, idev->nd_parms);
3297 		neigh_ifdown(&nd_tbl, dev);
3298 		in6_dev_put(idev);
3299 	}
3300 	return 0;
3301 }
3302 
3303 static void addrconf_rs_timer(unsigned long data)
3304 {
3305 	struct inet6_dev *idev = (struct inet6_dev *)data;
3306 	struct net_device *dev = idev->dev;
3307 	struct in6_addr lladdr;
3308 
3309 	write_lock(&idev->lock);
3310 	if (idev->dead || !(idev->if_flags & IF_READY))
3311 		goto out;
3312 
3313 	if (!ipv6_accept_ra(idev))
3314 		goto out;
3315 
3316 	/* Announcement received after solicitation was sent */
3317 	if (idev->if_flags & IF_RA_RCVD)
3318 		goto out;
3319 
3320 	if (idev->rs_probes++ < idev->cnf.rtr_solicits) {
3321 		write_unlock(&idev->lock);
3322 		if (!ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
3323 			ndisc_send_rs(dev, &lladdr,
3324 				      &in6addr_linklocal_allrouters);
3325 		else
3326 			goto put;
3327 
3328 		write_lock(&idev->lock);
3329 		/* The wait after the last probe can be shorter */
3330 		addrconf_mod_rs_timer(idev, (idev->rs_probes ==
3331 					     idev->cnf.rtr_solicits) ?
3332 				      idev->cnf.rtr_solicit_delay :
3333 				      idev->cnf.rtr_solicit_interval);
3334 	} else {
3335 		/*
3336 		 * Note: we do not support deprecated "all on-link"
3337 		 * assumption any longer.
3338 		 */
3339 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
3340 	}
3341 
3342 out:
3343 	write_unlock(&idev->lock);
3344 put:
3345 	in6_dev_put(idev);
3346 }
3347 
3348 /*
3349  *	Duplicate Address Detection
3350  */
3351 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
3352 {
3353 	unsigned long rand_num;
3354 	struct inet6_dev *idev = ifp->idev;
3355 
3356 	if (ifp->flags & IFA_F_OPTIMISTIC)
3357 		rand_num = 0;
3358 	else
3359 		rand_num = prandom_u32() % (idev->cnf.rtr_solicit_delay ? : 1);
3360 
3361 	ifp->dad_probes = idev->cnf.dad_transmits;
3362 	addrconf_mod_dad_work(ifp, rand_num);
3363 }
3364 
3365 static void addrconf_dad_begin(struct inet6_ifaddr *ifp)
3366 {
3367 	struct inet6_dev *idev = ifp->idev;
3368 	struct net_device *dev = idev->dev;
3369 
3370 	addrconf_join_solict(dev, &ifp->addr);
3371 
3372 	prandom_seed((__force u32) ifp->addr.s6_addr32[3]);
3373 
3374 	read_lock_bh(&idev->lock);
3375 	spin_lock(&ifp->lock);
3376 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
3377 		goto out;
3378 
3379 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
3380 	    idev->cnf.accept_dad < 1 ||
3381 	    !(ifp->flags&IFA_F_TENTATIVE) ||
3382 	    ifp->flags & IFA_F_NODAD) {
3383 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3384 		spin_unlock(&ifp->lock);
3385 		read_unlock_bh(&idev->lock);
3386 
3387 		addrconf_dad_completed(ifp);
3388 		return;
3389 	}
3390 
3391 	if (!(idev->if_flags & IF_READY)) {
3392 		spin_unlock(&ifp->lock);
3393 		read_unlock_bh(&idev->lock);
3394 		/*
3395 		 * If the device is not ready:
3396 		 * - keep it tentative if it is a permanent address.
3397 		 * - otherwise, kill it.
3398 		 */
3399 		in6_ifa_hold(ifp);
3400 		addrconf_dad_stop(ifp, 0);
3401 		return;
3402 	}
3403 
3404 	/*
3405 	 * Optimistic nodes can start receiving
3406 	 * Frames right away
3407 	 */
3408 	if (ifp->flags & IFA_F_OPTIMISTIC) {
3409 		ip6_ins_rt(ifp->rt);
3410 		if (ipv6_use_optimistic_addr(idev)) {
3411 			/* Because optimistic nodes can use this address,
3412 			 * notify listeners. If DAD fails, RTM_DELADDR is sent.
3413 			 */
3414 			ipv6_ifa_notify(RTM_NEWADDR, ifp);
3415 		}
3416 	}
3417 
3418 	addrconf_dad_kick(ifp);
3419 out:
3420 	spin_unlock(&ifp->lock);
3421 	read_unlock_bh(&idev->lock);
3422 }
3423 
3424 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
3425 {
3426 	bool begin_dad = false;
3427 
3428 	spin_lock_bh(&ifp->lock);
3429 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
3430 		ifp->state = INET6_IFADDR_STATE_PREDAD;
3431 		begin_dad = true;
3432 	}
3433 	spin_unlock_bh(&ifp->lock);
3434 
3435 	if (begin_dad)
3436 		addrconf_mod_dad_work(ifp, 0);
3437 }
3438 
3439 static void addrconf_dad_work(struct work_struct *w)
3440 {
3441 	struct inet6_ifaddr *ifp = container_of(to_delayed_work(w),
3442 						struct inet6_ifaddr,
3443 						dad_work);
3444 	struct inet6_dev *idev = ifp->idev;
3445 	struct in6_addr mcaddr;
3446 
3447 	enum {
3448 		DAD_PROCESS,
3449 		DAD_BEGIN,
3450 		DAD_ABORT,
3451 	} action = DAD_PROCESS;
3452 
3453 	rtnl_lock();
3454 
3455 	spin_lock_bh(&ifp->lock);
3456 	if (ifp->state == INET6_IFADDR_STATE_PREDAD) {
3457 		action = DAD_BEGIN;
3458 		ifp->state = INET6_IFADDR_STATE_DAD;
3459 	} else if (ifp->state == INET6_IFADDR_STATE_ERRDAD) {
3460 		action = DAD_ABORT;
3461 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
3462 	}
3463 	spin_unlock_bh(&ifp->lock);
3464 
3465 	if (action == DAD_BEGIN) {
3466 		addrconf_dad_begin(ifp);
3467 		goto out;
3468 	} else if (action == DAD_ABORT) {
3469 		addrconf_dad_stop(ifp, 1);
3470 		goto out;
3471 	}
3472 
3473 	if (!ifp->dad_probes && addrconf_dad_end(ifp))
3474 		goto out;
3475 
3476 	write_lock_bh(&idev->lock);
3477 	if (idev->dead || !(idev->if_flags & IF_READY)) {
3478 		write_unlock_bh(&idev->lock);
3479 		goto out;
3480 	}
3481 
3482 	spin_lock(&ifp->lock);
3483 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
3484 		spin_unlock(&ifp->lock);
3485 		write_unlock_bh(&idev->lock);
3486 		goto out;
3487 	}
3488 
3489 	if (ifp->dad_probes == 0) {
3490 		/*
3491 		 * DAD was successful
3492 		 */
3493 
3494 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3495 		spin_unlock(&ifp->lock);
3496 		write_unlock_bh(&idev->lock);
3497 
3498 		addrconf_dad_completed(ifp);
3499 
3500 		goto out;
3501 	}
3502 
3503 	ifp->dad_probes--;
3504 	addrconf_mod_dad_work(ifp,
3505 			      NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME));
3506 	spin_unlock(&ifp->lock);
3507 	write_unlock_bh(&idev->lock);
3508 
3509 	/* send a neighbour solicitation for our addr */
3510 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
3511 	ndisc_send_ns(ifp->idev->dev, NULL, &ifp->addr, &mcaddr, &in6addr_any);
3512 out:
3513 	in6_ifa_put(ifp);
3514 	rtnl_unlock();
3515 }
3516 
3517 /* ifp->idev must be at least read locked */
3518 static bool ipv6_lonely_lladdr(struct inet6_ifaddr *ifp)
3519 {
3520 	struct inet6_ifaddr *ifpiter;
3521 	struct inet6_dev *idev = ifp->idev;
3522 
3523 	list_for_each_entry_reverse(ifpiter, &idev->addr_list, if_list) {
3524 		if (ifpiter->scope > IFA_LINK)
3525 			break;
3526 		if (ifp != ifpiter && ifpiter->scope == IFA_LINK &&
3527 		    (ifpiter->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE|
3528 				       IFA_F_OPTIMISTIC|IFA_F_DADFAILED)) ==
3529 		    IFA_F_PERMANENT)
3530 			return false;
3531 	}
3532 	return true;
3533 }
3534 
3535 static void addrconf_dad_completed(struct inet6_ifaddr *ifp)
3536 {
3537 	struct net_device *dev = ifp->idev->dev;
3538 	struct in6_addr lladdr;
3539 	bool send_rs, send_mld;
3540 
3541 	addrconf_del_dad_work(ifp);
3542 
3543 	/*
3544 	 *	Configure the address for reception. Now it is valid.
3545 	 */
3546 
3547 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
3548 
3549 	/* If added prefix is link local and we are prepared to process
3550 	   router advertisements, start sending router solicitations.
3551 	 */
3552 
3553 	read_lock_bh(&ifp->idev->lock);
3554 	send_mld = ifp->scope == IFA_LINK && ipv6_lonely_lladdr(ifp);
3555 	send_rs = send_mld &&
3556 		  ipv6_accept_ra(ifp->idev) &&
3557 		  ifp->idev->cnf.rtr_solicits > 0 &&
3558 		  (dev->flags&IFF_LOOPBACK) == 0;
3559 	read_unlock_bh(&ifp->idev->lock);
3560 
3561 	/* While dad is in progress mld report's source address is in6_addrany.
3562 	 * Resend with proper ll now.
3563 	 */
3564 	if (send_mld)
3565 		ipv6_mc_dad_complete(ifp->idev);
3566 
3567 	if (send_rs) {
3568 		/*
3569 		 *	If a host as already performed a random delay
3570 		 *	[...] as part of DAD [...] there is no need
3571 		 *	to delay again before sending the first RS
3572 		 */
3573 		if (ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
3574 			return;
3575 		ndisc_send_rs(dev, &lladdr, &in6addr_linklocal_allrouters);
3576 
3577 		write_lock_bh(&ifp->idev->lock);
3578 		spin_lock(&ifp->lock);
3579 		ifp->idev->rs_probes = 1;
3580 		ifp->idev->if_flags |= IF_RS_SENT;
3581 		addrconf_mod_rs_timer(ifp->idev,
3582 				      ifp->idev->cnf.rtr_solicit_interval);
3583 		spin_unlock(&ifp->lock);
3584 		write_unlock_bh(&ifp->idev->lock);
3585 	}
3586 }
3587 
3588 static void addrconf_dad_run(struct inet6_dev *idev)
3589 {
3590 	struct inet6_ifaddr *ifp;
3591 
3592 	read_lock_bh(&idev->lock);
3593 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
3594 		spin_lock(&ifp->lock);
3595 		if (ifp->flags & IFA_F_TENTATIVE &&
3596 		    ifp->state == INET6_IFADDR_STATE_DAD)
3597 			addrconf_dad_kick(ifp);
3598 		spin_unlock(&ifp->lock);
3599 	}
3600 	read_unlock_bh(&idev->lock);
3601 }
3602 
3603 #ifdef CONFIG_PROC_FS
3604 struct if6_iter_state {
3605 	struct seq_net_private p;
3606 	int bucket;
3607 	int offset;
3608 };
3609 
3610 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
3611 {
3612 	struct inet6_ifaddr *ifa = NULL;
3613 	struct if6_iter_state *state = seq->private;
3614 	struct net *net = seq_file_net(seq);
3615 	int p = 0;
3616 
3617 	/* initial bucket if pos is 0 */
3618 	if (pos == 0) {
3619 		state->bucket = 0;
3620 		state->offset = 0;
3621 	}
3622 
3623 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
3624 		hlist_for_each_entry_rcu_bh(ifa, &inet6_addr_lst[state->bucket],
3625 					 addr_lst) {
3626 			if (!net_eq(dev_net(ifa->idev->dev), net))
3627 				continue;
3628 			/* sync with offset */
3629 			if (p < state->offset) {
3630 				p++;
3631 				continue;
3632 			}
3633 			state->offset++;
3634 			return ifa;
3635 		}
3636 
3637 		/* prepare for next bucket */
3638 		state->offset = 0;
3639 		p = 0;
3640 	}
3641 	return NULL;
3642 }
3643 
3644 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
3645 					 struct inet6_ifaddr *ifa)
3646 {
3647 	struct if6_iter_state *state = seq->private;
3648 	struct net *net = seq_file_net(seq);
3649 
3650 	hlist_for_each_entry_continue_rcu_bh(ifa, addr_lst) {
3651 		if (!net_eq(dev_net(ifa->idev->dev), net))
3652 			continue;
3653 		state->offset++;
3654 		return ifa;
3655 	}
3656 
3657 	while (++state->bucket < IN6_ADDR_HSIZE) {
3658 		state->offset = 0;
3659 		hlist_for_each_entry_rcu_bh(ifa,
3660 				     &inet6_addr_lst[state->bucket], addr_lst) {
3661 			if (!net_eq(dev_net(ifa->idev->dev), net))
3662 				continue;
3663 			state->offset++;
3664 			return ifa;
3665 		}
3666 	}
3667 
3668 	return NULL;
3669 }
3670 
3671 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
3672 	__acquires(rcu_bh)
3673 {
3674 	rcu_read_lock_bh();
3675 	return if6_get_first(seq, *pos);
3676 }
3677 
3678 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3679 {
3680 	struct inet6_ifaddr *ifa;
3681 
3682 	ifa = if6_get_next(seq, v);
3683 	++*pos;
3684 	return ifa;
3685 }
3686 
3687 static void if6_seq_stop(struct seq_file *seq, void *v)
3688 	__releases(rcu_bh)
3689 {
3690 	rcu_read_unlock_bh();
3691 }
3692 
3693 static int if6_seq_show(struct seq_file *seq, void *v)
3694 {
3695 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
3696 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
3697 		   &ifp->addr,
3698 		   ifp->idev->dev->ifindex,
3699 		   ifp->prefix_len,
3700 		   ifp->scope,
3701 		   (u8) ifp->flags,
3702 		   ifp->idev->dev->name);
3703 	return 0;
3704 }
3705 
3706 static const struct seq_operations if6_seq_ops = {
3707 	.start	= if6_seq_start,
3708 	.next	= if6_seq_next,
3709 	.show	= if6_seq_show,
3710 	.stop	= if6_seq_stop,
3711 };
3712 
3713 static int if6_seq_open(struct inode *inode, struct file *file)
3714 {
3715 	return seq_open_net(inode, file, &if6_seq_ops,
3716 			    sizeof(struct if6_iter_state));
3717 }
3718 
3719 static const struct file_operations if6_fops = {
3720 	.owner		= THIS_MODULE,
3721 	.open		= if6_seq_open,
3722 	.read		= seq_read,
3723 	.llseek		= seq_lseek,
3724 	.release	= seq_release_net,
3725 };
3726 
3727 static int __net_init if6_proc_net_init(struct net *net)
3728 {
3729 	if (!proc_create("if_inet6", S_IRUGO, net->proc_net, &if6_fops))
3730 		return -ENOMEM;
3731 	return 0;
3732 }
3733 
3734 static void __net_exit if6_proc_net_exit(struct net *net)
3735 {
3736 	remove_proc_entry("if_inet6", net->proc_net);
3737 }
3738 
3739 static struct pernet_operations if6_proc_net_ops = {
3740 	.init = if6_proc_net_init,
3741 	.exit = if6_proc_net_exit,
3742 };
3743 
3744 int __init if6_proc_init(void)
3745 {
3746 	return register_pernet_subsys(&if6_proc_net_ops);
3747 }
3748 
3749 void if6_proc_exit(void)
3750 {
3751 	unregister_pernet_subsys(&if6_proc_net_ops);
3752 }
3753 #endif	/* CONFIG_PROC_FS */
3754 
3755 #if IS_ENABLED(CONFIG_IPV6_MIP6)
3756 /* Check if address is a home address configured on any interface. */
3757 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
3758 {
3759 	int ret = 0;
3760 	struct inet6_ifaddr *ifp = NULL;
3761 	unsigned int hash = inet6_addr_hash(addr);
3762 
3763 	rcu_read_lock_bh();
3764 	hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[hash], addr_lst) {
3765 		if (!net_eq(dev_net(ifp->idev->dev), net))
3766 			continue;
3767 		if (ipv6_addr_equal(&ifp->addr, addr) &&
3768 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
3769 			ret = 1;
3770 			break;
3771 		}
3772 	}
3773 	rcu_read_unlock_bh();
3774 	return ret;
3775 }
3776 #endif
3777 
3778 /*
3779  *	Periodic address status verification
3780  */
3781 
3782 static void addrconf_verify_rtnl(void)
3783 {
3784 	unsigned long now, next, next_sec, next_sched;
3785 	struct inet6_ifaddr *ifp;
3786 	int i;
3787 
3788 	ASSERT_RTNL();
3789 
3790 	rcu_read_lock_bh();
3791 	now = jiffies;
3792 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
3793 
3794 	cancel_delayed_work(&addr_chk_work);
3795 
3796 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3797 restart:
3798 		hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[i], addr_lst) {
3799 			unsigned long age;
3800 
3801 			/* When setting preferred_lft to a value not zero or
3802 			 * infinity, while valid_lft is infinity
3803 			 * IFA_F_PERMANENT has a non-infinity life time.
3804 			 */
3805 			if ((ifp->flags & IFA_F_PERMANENT) &&
3806 			    (ifp->prefered_lft == INFINITY_LIFE_TIME))
3807 				continue;
3808 
3809 			spin_lock(&ifp->lock);
3810 			/* We try to batch several events at once. */
3811 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
3812 
3813 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
3814 			    age >= ifp->valid_lft) {
3815 				spin_unlock(&ifp->lock);
3816 				in6_ifa_hold(ifp);
3817 				ipv6_del_addr(ifp);
3818 				goto restart;
3819 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
3820 				spin_unlock(&ifp->lock);
3821 				continue;
3822 			} else if (age >= ifp->prefered_lft) {
3823 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
3824 				int deprecate = 0;
3825 
3826 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
3827 					deprecate = 1;
3828 					ifp->flags |= IFA_F_DEPRECATED;
3829 				}
3830 
3831 				if ((ifp->valid_lft != INFINITY_LIFE_TIME) &&
3832 				    (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)))
3833 					next = ifp->tstamp + ifp->valid_lft * HZ;
3834 
3835 				spin_unlock(&ifp->lock);
3836 
3837 				if (deprecate) {
3838 					in6_ifa_hold(ifp);
3839 
3840 					ipv6_ifa_notify(0, ifp);
3841 					in6_ifa_put(ifp);
3842 					goto restart;
3843 				}
3844 			} else if ((ifp->flags&IFA_F_TEMPORARY) &&
3845 				   !(ifp->flags&IFA_F_TENTATIVE)) {
3846 				unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
3847 					ifp->idev->cnf.dad_transmits *
3848 					NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME) / HZ;
3849 
3850 				if (age >= ifp->prefered_lft - regen_advance) {
3851 					struct inet6_ifaddr *ifpub = ifp->ifpub;
3852 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
3853 						next = ifp->tstamp + ifp->prefered_lft * HZ;
3854 					if (!ifp->regen_count && ifpub) {
3855 						ifp->regen_count++;
3856 						in6_ifa_hold(ifp);
3857 						in6_ifa_hold(ifpub);
3858 						spin_unlock(&ifp->lock);
3859 
3860 						spin_lock(&ifpub->lock);
3861 						ifpub->regen_count = 0;
3862 						spin_unlock(&ifpub->lock);
3863 						ipv6_create_tempaddr(ifpub, ifp);
3864 						in6_ifa_put(ifpub);
3865 						in6_ifa_put(ifp);
3866 						goto restart;
3867 					}
3868 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
3869 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
3870 				spin_unlock(&ifp->lock);
3871 			} else {
3872 				/* ifp->prefered_lft <= ifp->valid_lft */
3873 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
3874 					next = ifp->tstamp + ifp->prefered_lft * HZ;
3875 				spin_unlock(&ifp->lock);
3876 			}
3877 		}
3878 	}
3879 
3880 	next_sec = round_jiffies_up(next);
3881 	next_sched = next;
3882 
3883 	/* If rounded timeout is accurate enough, accept it. */
3884 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
3885 		next_sched = next_sec;
3886 
3887 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
3888 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
3889 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
3890 
3891 	ADBG(KERN_DEBUG "now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
3892 	      now, next, next_sec, next_sched);
3893 	mod_delayed_work(addrconf_wq, &addr_chk_work, next_sched - now);
3894 	rcu_read_unlock_bh();
3895 }
3896 
3897 static void addrconf_verify_work(struct work_struct *w)
3898 {
3899 	rtnl_lock();
3900 	addrconf_verify_rtnl();
3901 	rtnl_unlock();
3902 }
3903 
3904 static void addrconf_verify(void)
3905 {
3906 	mod_delayed_work(addrconf_wq, &addr_chk_work, 0);
3907 }
3908 
3909 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
3910 				     struct in6_addr **peer_pfx)
3911 {
3912 	struct in6_addr *pfx = NULL;
3913 
3914 	*peer_pfx = NULL;
3915 
3916 	if (addr)
3917 		pfx = nla_data(addr);
3918 
3919 	if (local) {
3920 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
3921 			*peer_pfx = pfx;
3922 		pfx = nla_data(local);
3923 	}
3924 
3925 	return pfx;
3926 }
3927 
3928 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
3929 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
3930 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
3931 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
3932 	[IFA_FLAGS]		= { .len = sizeof(u32) },
3933 };
3934 
3935 static int
3936 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh)
3937 {
3938 	struct net *net = sock_net(skb->sk);
3939 	struct ifaddrmsg *ifm;
3940 	struct nlattr *tb[IFA_MAX+1];
3941 	struct in6_addr *pfx, *peer_pfx;
3942 	u32 ifa_flags;
3943 	int err;
3944 
3945 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
3946 	if (err < 0)
3947 		return err;
3948 
3949 	ifm = nlmsg_data(nlh);
3950 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
3951 	if (pfx == NULL)
3952 		return -EINVAL;
3953 
3954 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
3955 
3956 	/* We ignore other flags so far. */
3957 	ifa_flags &= IFA_F_MANAGETEMPADDR;
3958 
3959 	return inet6_addr_del(net, ifm->ifa_index, ifa_flags, pfx,
3960 			      ifm->ifa_prefixlen);
3961 }
3962 
3963 static int inet6_addr_modify(struct inet6_ifaddr *ifp, u32 ifa_flags,
3964 			     u32 prefered_lft, u32 valid_lft)
3965 {
3966 	u32 flags;
3967 	clock_t expires;
3968 	unsigned long timeout;
3969 	bool was_managetempaddr;
3970 	bool had_prefixroute;
3971 
3972 	ASSERT_RTNL();
3973 
3974 	if (!valid_lft || (prefered_lft > valid_lft))
3975 		return -EINVAL;
3976 
3977 	if (ifa_flags & IFA_F_MANAGETEMPADDR &&
3978 	    (ifp->flags & IFA_F_TEMPORARY || ifp->prefix_len != 64))
3979 		return -EINVAL;
3980 
3981 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
3982 	if (addrconf_finite_timeout(timeout)) {
3983 		expires = jiffies_to_clock_t(timeout * HZ);
3984 		valid_lft = timeout;
3985 		flags = RTF_EXPIRES;
3986 	} else {
3987 		expires = 0;
3988 		flags = 0;
3989 		ifa_flags |= IFA_F_PERMANENT;
3990 	}
3991 
3992 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
3993 	if (addrconf_finite_timeout(timeout)) {
3994 		if (timeout == 0)
3995 			ifa_flags |= IFA_F_DEPRECATED;
3996 		prefered_lft = timeout;
3997 	}
3998 
3999 	spin_lock_bh(&ifp->lock);
4000 	was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;
4001 	had_prefixroute = ifp->flags & IFA_F_PERMANENT &&
4002 			  !(ifp->flags & IFA_F_NOPREFIXROUTE);
4003 	ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |
4004 			IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4005 			IFA_F_NOPREFIXROUTE);
4006 	ifp->flags |= ifa_flags;
4007 	ifp->tstamp = jiffies;
4008 	ifp->valid_lft = valid_lft;
4009 	ifp->prefered_lft = prefered_lft;
4010 
4011 	spin_unlock_bh(&ifp->lock);
4012 	if (!(ifp->flags&IFA_F_TENTATIVE))
4013 		ipv6_ifa_notify(0, ifp);
4014 
4015 	if (!(ifa_flags & IFA_F_NOPREFIXROUTE)) {
4016 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, ifp->idev->dev,
4017 				      expires, flags);
4018 	} else if (had_prefixroute) {
4019 		enum cleanup_prefix_rt_t action;
4020 		unsigned long rt_expires;
4021 
4022 		write_lock_bh(&ifp->idev->lock);
4023 		action = check_cleanup_prefix_route(ifp, &rt_expires);
4024 		write_unlock_bh(&ifp->idev->lock);
4025 
4026 		if (action != CLEANUP_PREFIX_RT_NOP) {
4027 			cleanup_prefix_route(ifp, rt_expires,
4028 				action == CLEANUP_PREFIX_RT_DEL);
4029 		}
4030 	}
4031 
4032 	if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {
4033 		if (was_managetempaddr && !(ifp->flags & IFA_F_MANAGETEMPADDR))
4034 			valid_lft = prefered_lft = 0;
4035 		manage_tempaddrs(ifp->idev, ifp, valid_lft, prefered_lft,
4036 				 !was_managetempaddr, jiffies);
4037 	}
4038 
4039 	addrconf_verify_rtnl();
4040 
4041 	return 0;
4042 }
4043 
4044 static int
4045 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh)
4046 {
4047 	struct net *net = sock_net(skb->sk);
4048 	struct ifaddrmsg *ifm;
4049 	struct nlattr *tb[IFA_MAX+1];
4050 	struct in6_addr *pfx, *peer_pfx;
4051 	struct inet6_ifaddr *ifa;
4052 	struct net_device *dev;
4053 	u32 valid_lft = INFINITY_LIFE_TIME, preferred_lft = INFINITY_LIFE_TIME;
4054 	u32 ifa_flags;
4055 	int err;
4056 
4057 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
4058 	if (err < 0)
4059 		return err;
4060 
4061 	ifm = nlmsg_data(nlh);
4062 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4063 	if (pfx == NULL)
4064 		return -EINVAL;
4065 
4066 	if (tb[IFA_CACHEINFO]) {
4067 		struct ifa_cacheinfo *ci;
4068 
4069 		ci = nla_data(tb[IFA_CACHEINFO]);
4070 		valid_lft = ci->ifa_valid;
4071 		preferred_lft = ci->ifa_prefered;
4072 	} else {
4073 		preferred_lft = INFINITY_LIFE_TIME;
4074 		valid_lft = INFINITY_LIFE_TIME;
4075 	}
4076 
4077 	dev =  __dev_get_by_index(net, ifm->ifa_index);
4078 	if (dev == NULL)
4079 		return -ENODEV;
4080 
4081 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
4082 
4083 	/* We ignore other flags so far. */
4084 	ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4085 		     IFA_F_NOPREFIXROUTE | IFA_F_MCAUTOJOIN;
4086 
4087 	ifa = ipv6_get_ifaddr(net, pfx, dev, 1);
4088 	if (ifa == NULL) {
4089 		/*
4090 		 * It would be best to check for !NLM_F_CREATE here but
4091 		 * userspace already relies on not having to provide this.
4092 		 */
4093 		return inet6_addr_add(net, ifm->ifa_index, pfx, peer_pfx,
4094 				      ifm->ifa_prefixlen, ifa_flags,
4095 				      preferred_lft, valid_lft);
4096 	}
4097 
4098 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
4099 	    !(nlh->nlmsg_flags & NLM_F_REPLACE))
4100 		err = -EEXIST;
4101 	else
4102 		err = inet6_addr_modify(ifa, ifa_flags, preferred_lft, valid_lft);
4103 
4104 	in6_ifa_put(ifa);
4105 
4106 	return err;
4107 }
4108 
4109 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u32 flags,
4110 			  u8 scope, int ifindex)
4111 {
4112 	struct ifaddrmsg *ifm;
4113 
4114 	ifm = nlmsg_data(nlh);
4115 	ifm->ifa_family = AF_INET6;
4116 	ifm->ifa_prefixlen = prefixlen;
4117 	ifm->ifa_flags = flags;
4118 	ifm->ifa_scope = scope;
4119 	ifm->ifa_index = ifindex;
4120 }
4121 
4122 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
4123 			 unsigned long tstamp, u32 preferred, u32 valid)
4124 {
4125 	struct ifa_cacheinfo ci;
4126 
4127 	ci.cstamp = cstamp_delta(cstamp);
4128 	ci.tstamp = cstamp_delta(tstamp);
4129 	ci.ifa_prefered = preferred;
4130 	ci.ifa_valid = valid;
4131 
4132 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
4133 }
4134 
4135 static inline int rt_scope(int ifa_scope)
4136 {
4137 	if (ifa_scope & IFA_HOST)
4138 		return RT_SCOPE_HOST;
4139 	else if (ifa_scope & IFA_LINK)
4140 		return RT_SCOPE_LINK;
4141 	else if (ifa_scope & IFA_SITE)
4142 		return RT_SCOPE_SITE;
4143 	else
4144 		return RT_SCOPE_UNIVERSE;
4145 }
4146 
4147 static inline int inet6_ifaddr_msgsize(void)
4148 {
4149 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
4150 	       + nla_total_size(16) /* IFA_LOCAL */
4151 	       + nla_total_size(16) /* IFA_ADDRESS */
4152 	       + nla_total_size(sizeof(struct ifa_cacheinfo))
4153 	       + nla_total_size(4)  /* IFA_FLAGS */;
4154 }
4155 
4156 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
4157 			     u32 portid, u32 seq, int event, unsigned int flags)
4158 {
4159 	struct nlmsghdr  *nlh;
4160 	u32 preferred, valid;
4161 
4162 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4163 	if (nlh == NULL)
4164 		return -EMSGSIZE;
4165 
4166 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
4167 		      ifa->idev->dev->ifindex);
4168 
4169 	if (!((ifa->flags&IFA_F_PERMANENT) &&
4170 	      (ifa->prefered_lft == INFINITY_LIFE_TIME))) {
4171 		preferred = ifa->prefered_lft;
4172 		valid = ifa->valid_lft;
4173 		if (preferred != INFINITY_LIFE_TIME) {
4174 			long tval = (jiffies - ifa->tstamp)/HZ;
4175 			if (preferred > tval)
4176 				preferred -= tval;
4177 			else
4178 				preferred = 0;
4179 			if (valid != INFINITY_LIFE_TIME) {
4180 				if (valid > tval)
4181 					valid -= tval;
4182 				else
4183 					valid = 0;
4184 			}
4185 		}
4186 	} else {
4187 		preferred = INFINITY_LIFE_TIME;
4188 		valid = INFINITY_LIFE_TIME;
4189 	}
4190 
4191 	if (!ipv6_addr_any(&ifa->peer_addr)) {
4192 		if (nla_put(skb, IFA_LOCAL, 16, &ifa->addr) < 0 ||
4193 		    nla_put(skb, IFA_ADDRESS, 16, &ifa->peer_addr) < 0)
4194 			goto error;
4195 	} else
4196 		if (nla_put(skb, IFA_ADDRESS, 16, &ifa->addr) < 0)
4197 			goto error;
4198 
4199 	if (put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0)
4200 		goto error;
4201 
4202 	if (nla_put_u32(skb, IFA_FLAGS, ifa->flags) < 0)
4203 		goto error;
4204 
4205 	nlmsg_end(skb, nlh);
4206 	return 0;
4207 
4208 error:
4209 	nlmsg_cancel(skb, nlh);
4210 	return -EMSGSIZE;
4211 }
4212 
4213 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
4214 				u32 portid, u32 seq, int event, u16 flags)
4215 {
4216 	struct nlmsghdr  *nlh;
4217 	u8 scope = RT_SCOPE_UNIVERSE;
4218 	int ifindex = ifmca->idev->dev->ifindex;
4219 
4220 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
4221 		scope = RT_SCOPE_SITE;
4222 
4223 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4224 	if (nlh == NULL)
4225 		return -EMSGSIZE;
4226 
4227 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4228 	if (nla_put(skb, IFA_MULTICAST, 16, &ifmca->mca_addr) < 0 ||
4229 	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
4230 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4231 		nlmsg_cancel(skb, nlh);
4232 		return -EMSGSIZE;
4233 	}
4234 
4235 	nlmsg_end(skb, nlh);
4236 	return 0;
4237 }
4238 
4239 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
4240 				u32 portid, u32 seq, int event, unsigned int flags)
4241 {
4242 	struct nlmsghdr  *nlh;
4243 	u8 scope = RT_SCOPE_UNIVERSE;
4244 	int ifindex = ifaca->aca_idev->dev->ifindex;
4245 
4246 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
4247 		scope = RT_SCOPE_SITE;
4248 
4249 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4250 	if (nlh == NULL)
4251 		return -EMSGSIZE;
4252 
4253 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4254 	if (nla_put(skb, IFA_ANYCAST, 16, &ifaca->aca_addr) < 0 ||
4255 	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
4256 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4257 		nlmsg_cancel(skb, nlh);
4258 		return -EMSGSIZE;
4259 	}
4260 
4261 	nlmsg_end(skb, nlh);
4262 	return 0;
4263 }
4264 
4265 enum addr_type_t {
4266 	UNICAST_ADDR,
4267 	MULTICAST_ADDR,
4268 	ANYCAST_ADDR,
4269 };
4270 
4271 /* called with rcu_read_lock() */
4272 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
4273 			  struct netlink_callback *cb, enum addr_type_t type,
4274 			  int s_ip_idx, int *p_ip_idx)
4275 {
4276 	struct ifmcaddr6 *ifmca;
4277 	struct ifacaddr6 *ifaca;
4278 	int err = 1;
4279 	int ip_idx = *p_ip_idx;
4280 
4281 	read_lock_bh(&idev->lock);
4282 	switch (type) {
4283 	case UNICAST_ADDR: {
4284 		struct inet6_ifaddr *ifa;
4285 
4286 		/* unicast address incl. temp addr */
4287 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
4288 			if (++ip_idx < s_ip_idx)
4289 				continue;
4290 			err = inet6_fill_ifaddr(skb, ifa,
4291 						NETLINK_CB(cb->skb).portid,
4292 						cb->nlh->nlmsg_seq,
4293 						RTM_NEWADDR,
4294 						NLM_F_MULTI);
4295 			if (err < 0)
4296 				break;
4297 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
4298 		}
4299 		break;
4300 	}
4301 	case MULTICAST_ADDR:
4302 		/* multicast address */
4303 		for (ifmca = idev->mc_list; ifmca;
4304 		     ifmca = ifmca->next, ip_idx++) {
4305 			if (ip_idx < s_ip_idx)
4306 				continue;
4307 			err = inet6_fill_ifmcaddr(skb, ifmca,
4308 						  NETLINK_CB(cb->skb).portid,
4309 						  cb->nlh->nlmsg_seq,
4310 						  RTM_GETMULTICAST,
4311 						  NLM_F_MULTI);
4312 			if (err < 0)
4313 				break;
4314 		}
4315 		break;
4316 	case ANYCAST_ADDR:
4317 		/* anycast address */
4318 		for (ifaca = idev->ac_list; ifaca;
4319 		     ifaca = ifaca->aca_next, ip_idx++) {
4320 			if (ip_idx < s_ip_idx)
4321 				continue;
4322 			err = inet6_fill_ifacaddr(skb, ifaca,
4323 						  NETLINK_CB(cb->skb).portid,
4324 						  cb->nlh->nlmsg_seq,
4325 						  RTM_GETANYCAST,
4326 						  NLM_F_MULTI);
4327 			if (err < 0)
4328 				break;
4329 		}
4330 		break;
4331 	default:
4332 		break;
4333 	}
4334 	read_unlock_bh(&idev->lock);
4335 	*p_ip_idx = ip_idx;
4336 	return err;
4337 }
4338 
4339 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
4340 			   enum addr_type_t type)
4341 {
4342 	struct net *net = sock_net(skb->sk);
4343 	int h, s_h;
4344 	int idx, ip_idx;
4345 	int s_idx, s_ip_idx;
4346 	struct net_device *dev;
4347 	struct inet6_dev *idev;
4348 	struct hlist_head *head;
4349 
4350 	s_h = cb->args[0];
4351 	s_idx = idx = cb->args[1];
4352 	s_ip_idx = ip_idx = cb->args[2];
4353 
4354 	rcu_read_lock();
4355 	cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^ net->dev_base_seq;
4356 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
4357 		idx = 0;
4358 		head = &net->dev_index_head[h];
4359 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
4360 			if (idx < s_idx)
4361 				goto cont;
4362 			if (h > s_h || idx > s_idx)
4363 				s_ip_idx = 0;
4364 			ip_idx = 0;
4365 			idev = __in6_dev_get(dev);
4366 			if (!idev)
4367 				goto cont;
4368 
4369 			if (in6_dump_addrs(idev, skb, cb, type,
4370 					   s_ip_idx, &ip_idx) < 0)
4371 				goto done;
4372 cont:
4373 			idx++;
4374 		}
4375 	}
4376 done:
4377 	rcu_read_unlock();
4378 	cb->args[0] = h;
4379 	cb->args[1] = idx;
4380 	cb->args[2] = ip_idx;
4381 
4382 	return skb->len;
4383 }
4384 
4385 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
4386 {
4387 	enum addr_type_t type = UNICAST_ADDR;
4388 
4389 	return inet6_dump_addr(skb, cb, type);
4390 }
4391 
4392 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
4393 {
4394 	enum addr_type_t type = MULTICAST_ADDR;
4395 
4396 	return inet6_dump_addr(skb, cb, type);
4397 }
4398 
4399 
4400 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
4401 {
4402 	enum addr_type_t type = ANYCAST_ADDR;
4403 
4404 	return inet6_dump_addr(skb, cb, type);
4405 }
4406 
4407 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh)
4408 {
4409 	struct net *net = sock_net(in_skb->sk);
4410 	struct ifaddrmsg *ifm;
4411 	struct nlattr *tb[IFA_MAX+1];
4412 	struct in6_addr *addr = NULL, *peer;
4413 	struct net_device *dev = NULL;
4414 	struct inet6_ifaddr *ifa;
4415 	struct sk_buff *skb;
4416 	int err;
4417 
4418 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
4419 	if (err < 0)
4420 		goto errout;
4421 
4422 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
4423 	if (addr == NULL) {
4424 		err = -EINVAL;
4425 		goto errout;
4426 	}
4427 
4428 	ifm = nlmsg_data(nlh);
4429 	if (ifm->ifa_index)
4430 		dev = __dev_get_by_index(net, ifm->ifa_index);
4431 
4432 	ifa = ipv6_get_ifaddr(net, addr, dev, 1);
4433 	if (!ifa) {
4434 		err = -EADDRNOTAVAIL;
4435 		goto errout;
4436 	}
4437 
4438 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
4439 	if (!skb) {
4440 		err = -ENOBUFS;
4441 		goto errout_ifa;
4442 	}
4443 
4444 	err = inet6_fill_ifaddr(skb, ifa, NETLINK_CB(in_skb).portid,
4445 				nlh->nlmsg_seq, RTM_NEWADDR, 0);
4446 	if (err < 0) {
4447 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
4448 		WARN_ON(err == -EMSGSIZE);
4449 		kfree_skb(skb);
4450 		goto errout_ifa;
4451 	}
4452 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
4453 errout_ifa:
4454 	in6_ifa_put(ifa);
4455 errout:
4456 	return err;
4457 }
4458 
4459 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
4460 {
4461 	struct sk_buff *skb;
4462 	struct net *net = dev_net(ifa->idev->dev);
4463 	int err = -ENOBUFS;
4464 
4465 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
4466 	if (skb == NULL)
4467 		goto errout;
4468 
4469 	err = inet6_fill_ifaddr(skb, ifa, 0, 0, event, 0);
4470 	if (err < 0) {
4471 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
4472 		WARN_ON(err == -EMSGSIZE);
4473 		kfree_skb(skb);
4474 		goto errout;
4475 	}
4476 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
4477 	return;
4478 errout:
4479 	if (err < 0)
4480 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
4481 }
4482 
4483 static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
4484 				__s32 *array, int bytes)
4485 {
4486 	BUG_ON(bytes < (DEVCONF_MAX * 4));
4487 
4488 	memset(array, 0, bytes);
4489 	array[DEVCONF_FORWARDING] = cnf->forwarding;
4490 	array[DEVCONF_HOPLIMIT] = cnf->hop_limit;
4491 	array[DEVCONF_MTU6] = cnf->mtu6;
4492 	array[DEVCONF_ACCEPT_RA] = cnf->accept_ra;
4493 	array[DEVCONF_ACCEPT_REDIRECTS] = cnf->accept_redirects;
4494 	array[DEVCONF_AUTOCONF] = cnf->autoconf;
4495 	array[DEVCONF_DAD_TRANSMITS] = cnf->dad_transmits;
4496 	array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
4497 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
4498 		jiffies_to_msecs(cnf->rtr_solicit_interval);
4499 	array[DEVCONF_RTR_SOLICIT_DELAY] =
4500 		jiffies_to_msecs(cnf->rtr_solicit_delay);
4501 	array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;
4502 	array[DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL] =
4503 		jiffies_to_msecs(cnf->mldv1_unsolicited_report_interval);
4504 	array[DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL] =
4505 		jiffies_to_msecs(cnf->mldv2_unsolicited_report_interval);
4506 	array[DEVCONF_USE_TEMPADDR] = cnf->use_tempaddr;
4507 	array[DEVCONF_TEMP_VALID_LFT] = cnf->temp_valid_lft;
4508 	array[DEVCONF_TEMP_PREFERED_LFT] = cnf->temp_prefered_lft;
4509 	array[DEVCONF_REGEN_MAX_RETRY] = cnf->regen_max_retry;
4510 	array[DEVCONF_MAX_DESYNC_FACTOR] = cnf->max_desync_factor;
4511 	array[DEVCONF_MAX_ADDRESSES] = cnf->max_addresses;
4512 	array[DEVCONF_ACCEPT_RA_DEFRTR] = cnf->accept_ra_defrtr;
4513 	array[DEVCONF_ACCEPT_RA_PINFO] = cnf->accept_ra_pinfo;
4514 #ifdef CONFIG_IPV6_ROUTER_PREF
4515 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = cnf->accept_ra_rtr_pref;
4516 	array[DEVCONF_RTR_PROBE_INTERVAL] =
4517 		jiffies_to_msecs(cnf->rtr_probe_interval);
4518 #ifdef CONFIG_IPV6_ROUTE_INFO
4519 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
4520 #endif
4521 #endif
4522 	array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
4523 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
4524 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
4525 	array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
4526 	array[DEVCONF_USE_OPTIMISTIC] = cnf->use_optimistic;
4527 #endif
4528 #ifdef CONFIG_IPV6_MROUTE
4529 	array[DEVCONF_MC_FORWARDING] = cnf->mc_forwarding;
4530 #endif
4531 	array[DEVCONF_DISABLE_IPV6] = cnf->disable_ipv6;
4532 	array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad;
4533 	array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao;
4534 	array[DEVCONF_NDISC_NOTIFY] = cnf->ndisc_notify;
4535 	array[DEVCONF_SUPPRESS_FRAG_NDISC] = cnf->suppress_frag_ndisc;
4536 	array[DEVCONF_ACCEPT_RA_FROM_LOCAL] = cnf->accept_ra_from_local;
4537 	array[DEVCONF_ACCEPT_RA_MTU] = cnf->accept_ra_mtu;
4538 	/* we omit DEVCONF_STABLE_SECRET for now */
4539 }
4540 
4541 static inline size_t inet6_ifla6_size(void)
4542 {
4543 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
4544 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
4545 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
4546 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
4547 	     + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
4548 	     + nla_total_size(sizeof(struct in6_addr)); /* IFLA_INET6_TOKEN */
4549 }
4550 
4551 static inline size_t inet6_if_nlmsg_size(void)
4552 {
4553 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
4554 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
4555 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
4556 	       + nla_total_size(4) /* IFLA_MTU */
4557 	       + nla_total_size(4) /* IFLA_LINK */
4558 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
4559 }
4560 
4561 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
4562 				      int items, int bytes)
4563 {
4564 	int i;
4565 	int pad = bytes - sizeof(u64) * items;
4566 	BUG_ON(pad < 0);
4567 
4568 	/* Use put_unaligned() because stats may not be aligned for u64. */
4569 	put_unaligned(items, &stats[0]);
4570 	for (i = 1; i < items; i++)
4571 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
4572 
4573 	memset(&stats[items], 0, pad);
4574 }
4575 
4576 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu *mib,
4577 				      int items, int bytes, size_t syncpoff)
4578 {
4579 	int i;
4580 	int pad = bytes - sizeof(u64) * items;
4581 	BUG_ON(pad < 0);
4582 
4583 	/* Use put_unaligned() because stats may not be aligned for u64. */
4584 	put_unaligned(items, &stats[0]);
4585 	for (i = 1; i < items; i++)
4586 		put_unaligned(snmp_fold_field64(mib, i, syncpoff), &stats[i]);
4587 
4588 	memset(&stats[items], 0, pad);
4589 }
4590 
4591 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
4592 			     int bytes)
4593 {
4594 	switch (attrtype) {
4595 	case IFLA_INET6_STATS:
4596 		__snmp6_fill_stats64(stats, idev->stats.ipv6,
4597 				     IPSTATS_MIB_MAX, bytes, offsetof(struct ipstats_mib, syncp));
4598 		break;
4599 	case IFLA_INET6_ICMP6STATS:
4600 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, ICMP6_MIB_MAX, bytes);
4601 		break;
4602 	}
4603 }
4604 
4605 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev)
4606 {
4607 	struct nlattr *nla;
4608 	struct ifla_cacheinfo ci;
4609 
4610 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, idev->if_flags))
4611 		goto nla_put_failure;
4612 	ci.max_reasm_len = IPV6_MAXPLEN;
4613 	ci.tstamp = cstamp_delta(idev->tstamp);
4614 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
4615 	ci.retrans_time = jiffies_to_msecs(NEIGH_VAR(idev->nd_parms, RETRANS_TIME));
4616 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
4617 		goto nla_put_failure;
4618 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
4619 	if (nla == NULL)
4620 		goto nla_put_failure;
4621 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
4622 
4623 	/* XXX - MC not implemented */
4624 
4625 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
4626 	if (nla == NULL)
4627 		goto nla_put_failure;
4628 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
4629 
4630 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
4631 	if (nla == NULL)
4632 		goto nla_put_failure;
4633 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
4634 
4635 	nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
4636 	if (nla == NULL)
4637 		goto nla_put_failure;
4638 
4639 	if (nla_put_u8(skb, IFLA_INET6_ADDR_GEN_MODE, idev->addr_gen_mode))
4640 		goto nla_put_failure;
4641 
4642 	read_lock_bh(&idev->lock);
4643 	memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
4644 	read_unlock_bh(&idev->lock);
4645 
4646 	return 0;
4647 
4648 nla_put_failure:
4649 	return -EMSGSIZE;
4650 }
4651 
4652 static size_t inet6_get_link_af_size(const struct net_device *dev)
4653 {
4654 	if (!__in6_dev_get(dev))
4655 		return 0;
4656 
4657 	return inet6_ifla6_size();
4658 }
4659 
4660 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev)
4661 {
4662 	struct inet6_dev *idev = __in6_dev_get(dev);
4663 
4664 	if (!idev)
4665 		return -ENODATA;
4666 
4667 	if (inet6_fill_ifla6_attrs(skb, idev) < 0)
4668 		return -EMSGSIZE;
4669 
4670 	return 0;
4671 }
4672 
4673 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token)
4674 {
4675 	struct inet6_ifaddr *ifp;
4676 	struct net_device *dev = idev->dev;
4677 	bool update_rs = false;
4678 	struct in6_addr ll_addr;
4679 
4680 	ASSERT_RTNL();
4681 
4682 	if (token == NULL)
4683 		return -EINVAL;
4684 	if (ipv6_addr_any(token))
4685 		return -EINVAL;
4686 	if (dev->flags & (IFF_LOOPBACK | IFF_NOARP))
4687 		return -EINVAL;
4688 	if (!ipv6_accept_ra(idev))
4689 		return -EINVAL;
4690 	if (idev->cnf.rtr_solicits <= 0)
4691 		return -EINVAL;
4692 
4693 	write_lock_bh(&idev->lock);
4694 
4695 	BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
4696 	memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
4697 
4698 	write_unlock_bh(&idev->lock);
4699 
4700 	if (!idev->dead && (idev->if_flags & IF_READY) &&
4701 	    !ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
4702 			     IFA_F_OPTIMISTIC)) {
4703 
4704 		/* If we're not ready, then normal ifup will take care
4705 		 * of this. Otherwise, we need to request our rs here.
4706 		 */
4707 		ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
4708 		update_rs = true;
4709 	}
4710 
4711 	write_lock_bh(&idev->lock);
4712 
4713 	if (update_rs) {
4714 		idev->if_flags |= IF_RS_SENT;
4715 		idev->rs_probes = 1;
4716 		addrconf_mod_rs_timer(idev, idev->cnf.rtr_solicit_interval);
4717 	}
4718 
4719 	/* Well, that's kinda nasty ... */
4720 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
4721 		spin_lock(&ifp->lock);
4722 		if (ifp->tokenized) {
4723 			ifp->valid_lft = 0;
4724 			ifp->prefered_lft = 0;
4725 		}
4726 		spin_unlock(&ifp->lock);
4727 	}
4728 
4729 	write_unlock_bh(&idev->lock);
4730 	inet6_ifinfo_notify(RTM_NEWLINK, idev);
4731 	addrconf_verify_rtnl();
4732 	return 0;
4733 }
4734 
4735 static const struct nla_policy inet6_af_policy[IFLA_INET6_MAX + 1] = {
4736 	[IFLA_INET6_ADDR_GEN_MODE]	= { .type = NLA_U8 },
4737 	[IFLA_INET6_TOKEN]		= { .len = sizeof(struct in6_addr) },
4738 };
4739 
4740 static int inet6_validate_link_af(const struct net_device *dev,
4741 				  const struct nlattr *nla)
4742 {
4743 	struct nlattr *tb[IFLA_INET6_MAX + 1];
4744 
4745 	if (dev && !__in6_dev_get(dev))
4746 		return -EAFNOSUPPORT;
4747 
4748 	return nla_parse_nested(tb, IFLA_INET6_MAX, nla, inet6_af_policy);
4749 }
4750 
4751 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla)
4752 {
4753 	int err = -EINVAL;
4754 	struct inet6_dev *idev = __in6_dev_get(dev);
4755 	struct nlattr *tb[IFLA_INET6_MAX + 1];
4756 
4757 	if (!idev)
4758 		return -EAFNOSUPPORT;
4759 
4760 	if (nla_parse_nested(tb, IFLA_INET6_MAX, nla, NULL) < 0)
4761 		BUG();
4762 
4763 	if (tb[IFLA_INET6_TOKEN]) {
4764 		err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]));
4765 		if (err)
4766 			return err;
4767 	}
4768 
4769 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
4770 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
4771 
4772 		if (mode != IN6_ADDR_GEN_MODE_EUI64 &&
4773 		    mode != IN6_ADDR_GEN_MODE_NONE &&
4774 		    mode != IN6_ADDR_GEN_MODE_STABLE_PRIVACY)
4775 			return -EINVAL;
4776 
4777 		if (mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
4778 		    !idev->cnf.stable_secret.initialized &&
4779 		    !dev_net(dev)->ipv6.devconf_dflt->stable_secret.initialized)
4780 			return -EINVAL;
4781 
4782 		idev->addr_gen_mode = mode;
4783 		err = 0;
4784 	}
4785 
4786 	return err;
4787 }
4788 
4789 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
4790 			     u32 portid, u32 seq, int event, unsigned int flags)
4791 {
4792 	struct net_device *dev = idev->dev;
4793 	struct ifinfomsg *hdr;
4794 	struct nlmsghdr *nlh;
4795 	void *protoinfo;
4796 
4797 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
4798 	if (nlh == NULL)
4799 		return -EMSGSIZE;
4800 
4801 	hdr = nlmsg_data(nlh);
4802 	hdr->ifi_family = AF_INET6;
4803 	hdr->__ifi_pad = 0;
4804 	hdr->ifi_type = dev->type;
4805 	hdr->ifi_index = dev->ifindex;
4806 	hdr->ifi_flags = dev_get_flags(dev);
4807 	hdr->ifi_change = 0;
4808 
4809 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
4810 	    (dev->addr_len &&
4811 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
4812 	    nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
4813 	    (dev->ifindex != dev->iflink &&
4814 	     nla_put_u32(skb, IFLA_LINK, dev->iflink)))
4815 		goto nla_put_failure;
4816 	protoinfo = nla_nest_start(skb, IFLA_PROTINFO);
4817 	if (protoinfo == NULL)
4818 		goto nla_put_failure;
4819 
4820 	if (inet6_fill_ifla6_attrs(skb, idev) < 0)
4821 		goto nla_put_failure;
4822 
4823 	nla_nest_end(skb, protoinfo);
4824 	nlmsg_end(skb, nlh);
4825 	return 0;
4826 
4827 nla_put_failure:
4828 	nlmsg_cancel(skb, nlh);
4829 	return -EMSGSIZE;
4830 }
4831 
4832 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
4833 {
4834 	struct net *net = sock_net(skb->sk);
4835 	int h, s_h;
4836 	int idx = 0, s_idx;
4837 	struct net_device *dev;
4838 	struct inet6_dev *idev;
4839 	struct hlist_head *head;
4840 
4841 	s_h = cb->args[0];
4842 	s_idx = cb->args[1];
4843 
4844 	rcu_read_lock();
4845 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
4846 		idx = 0;
4847 		head = &net->dev_index_head[h];
4848 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
4849 			if (idx < s_idx)
4850 				goto cont;
4851 			idev = __in6_dev_get(dev);
4852 			if (!idev)
4853 				goto cont;
4854 			if (inet6_fill_ifinfo(skb, idev,
4855 					      NETLINK_CB(cb->skb).portid,
4856 					      cb->nlh->nlmsg_seq,
4857 					      RTM_NEWLINK, NLM_F_MULTI) < 0)
4858 				goto out;
4859 cont:
4860 			idx++;
4861 		}
4862 	}
4863 out:
4864 	rcu_read_unlock();
4865 	cb->args[1] = idx;
4866 	cb->args[0] = h;
4867 
4868 	return skb->len;
4869 }
4870 
4871 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
4872 {
4873 	struct sk_buff *skb;
4874 	struct net *net = dev_net(idev->dev);
4875 	int err = -ENOBUFS;
4876 
4877 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
4878 	if (skb == NULL)
4879 		goto errout;
4880 
4881 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
4882 	if (err < 0) {
4883 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
4884 		WARN_ON(err == -EMSGSIZE);
4885 		kfree_skb(skb);
4886 		goto errout;
4887 	}
4888 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
4889 	return;
4890 errout:
4891 	if (err < 0)
4892 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
4893 }
4894 
4895 static inline size_t inet6_prefix_nlmsg_size(void)
4896 {
4897 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
4898 	       + nla_total_size(sizeof(struct in6_addr))
4899 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
4900 }
4901 
4902 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
4903 			     struct prefix_info *pinfo, u32 portid, u32 seq,
4904 			     int event, unsigned int flags)
4905 {
4906 	struct prefixmsg *pmsg;
4907 	struct nlmsghdr *nlh;
4908 	struct prefix_cacheinfo	ci;
4909 
4910 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
4911 	if (nlh == NULL)
4912 		return -EMSGSIZE;
4913 
4914 	pmsg = nlmsg_data(nlh);
4915 	pmsg->prefix_family = AF_INET6;
4916 	pmsg->prefix_pad1 = 0;
4917 	pmsg->prefix_pad2 = 0;
4918 	pmsg->prefix_ifindex = idev->dev->ifindex;
4919 	pmsg->prefix_len = pinfo->prefix_len;
4920 	pmsg->prefix_type = pinfo->type;
4921 	pmsg->prefix_pad3 = 0;
4922 	pmsg->prefix_flags = 0;
4923 	if (pinfo->onlink)
4924 		pmsg->prefix_flags |= IF_PREFIX_ONLINK;
4925 	if (pinfo->autoconf)
4926 		pmsg->prefix_flags |= IF_PREFIX_AUTOCONF;
4927 
4928 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
4929 		goto nla_put_failure;
4930 	ci.preferred_time = ntohl(pinfo->prefered);
4931 	ci.valid_time = ntohl(pinfo->valid);
4932 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
4933 		goto nla_put_failure;
4934 	nlmsg_end(skb, nlh);
4935 	return 0;
4936 
4937 nla_put_failure:
4938 	nlmsg_cancel(skb, nlh);
4939 	return -EMSGSIZE;
4940 }
4941 
4942 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
4943 			 struct prefix_info *pinfo)
4944 {
4945 	struct sk_buff *skb;
4946 	struct net *net = dev_net(idev->dev);
4947 	int err = -ENOBUFS;
4948 
4949 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
4950 	if (skb == NULL)
4951 		goto errout;
4952 
4953 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
4954 	if (err < 0) {
4955 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
4956 		WARN_ON(err == -EMSGSIZE);
4957 		kfree_skb(skb);
4958 		goto errout;
4959 	}
4960 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
4961 	return;
4962 errout:
4963 	if (err < 0)
4964 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
4965 }
4966 
4967 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
4968 {
4969 	struct net *net = dev_net(ifp->idev->dev);
4970 
4971 	if (event)
4972 		ASSERT_RTNL();
4973 
4974 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
4975 
4976 	switch (event) {
4977 	case RTM_NEWADDR:
4978 		/*
4979 		 * If the address was optimistic
4980 		 * we inserted the route at the start of
4981 		 * our DAD process, so we don't need
4982 		 * to do it again
4983 		 */
4984 		if (!(ifp->rt->rt6i_node))
4985 			ip6_ins_rt(ifp->rt);
4986 		if (ifp->idev->cnf.forwarding)
4987 			addrconf_join_anycast(ifp);
4988 		if (!ipv6_addr_any(&ifp->peer_addr))
4989 			addrconf_prefix_route(&ifp->peer_addr, 128,
4990 					      ifp->idev->dev, 0, 0);
4991 		break;
4992 	case RTM_DELADDR:
4993 		if (ifp->idev->cnf.forwarding)
4994 			addrconf_leave_anycast(ifp);
4995 		addrconf_leave_solict(ifp->idev, &ifp->addr);
4996 		if (!ipv6_addr_any(&ifp->peer_addr)) {
4997 			struct rt6_info *rt;
4998 
4999 			rt = addrconf_get_prefix_route(&ifp->peer_addr, 128,
5000 						       ifp->idev->dev, 0, 0);
5001 			if (rt && ip6_del_rt(rt))
5002 				dst_free(&rt->dst);
5003 		}
5004 		dst_hold(&ifp->rt->dst);
5005 
5006 		if (ip6_del_rt(ifp->rt))
5007 			dst_free(&ifp->rt->dst);
5008 
5009 		rt_genid_bump_ipv6(net);
5010 		break;
5011 	}
5012 	atomic_inc(&net->ipv6.dev_addr_genid);
5013 }
5014 
5015 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
5016 {
5017 	rcu_read_lock_bh();
5018 	if (likely(ifp->idev->dead == 0))
5019 		__ipv6_ifa_notify(event, ifp);
5020 	rcu_read_unlock_bh();
5021 }
5022 
5023 #ifdef CONFIG_SYSCTL
5024 
5025 static
5026 int addrconf_sysctl_forward(struct ctl_table *ctl, int write,
5027 			   void __user *buffer, size_t *lenp, loff_t *ppos)
5028 {
5029 	int *valp = ctl->data;
5030 	int val = *valp;
5031 	loff_t pos = *ppos;
5032 	struct ctl_table lctl;
5033 	int ret;
5034 
5035 	/*
5036 	 * ctl->data points to idev->cnf.forwarding, we should
5037 	 * not modify it until we get the rtnl lock.
5038 	 */
5039 	lctl = *ctl;
5040 	lctl.data = &val;
5041 
5042 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5043 
5044 	if (write)
5045 		ret = addrconf_fixup_forwarding(ctl, valp, val);
5046 	if (ret)
5047 		*ppos = pos;
5048 	return ret;
5049 }
5050 
5051 static
5052 int addrconf_sysctl_mtu(struct ctl_table *ctl, int write,
5053 			void __user *buffer, size_t *lenp, loff_t *ppos)
5054 {
5055 	struct inet6_dev *idev = ctl->extra1;
5056 	int min_mtu = IPV6_MIN_MTU;
5057 	struct ctl_table lctl;
5058 
5059 	lctl = *ctl;
5060 	lctl.extra1 = &min_mtu;
5061 	lctl.extra2 = idev ? &idev->dev->mtu : NULL;
5062 
5063 	return proc_dointvec_minmax(&lctl, write, buffer, lenp, ppos);
5064 }
5065 
5066 static void dev_disable_change(struct inet6_dev *idev)
5067 {
5068 	struct netdev_notifier_info info;
5069 
5070 	if (!idev || !idev->dev)
5071 		return;
5072 
5073 	netdev_notifier_info_init(&info, idev->dev);
5074 	if (idev->cnf.disable_ipv6)
5075 		addrconf_notify(NULL, NETDEV_DOWN, &info);
5076 	else
5077 		addrconf_notify(NULL, NETDEV_UP, &info);
5078 }
5079 
5080 static void addrconf_disable_change(struct net *net, __s32 newf)
5081 {
5082 	struct net_device *dev;
5083 	struct inet6_dev *idev;
5084 
5085 	rcu_read_lock();
5086 	for_each_netdev_rcu(net, dev) {
5087 		idev = __in6_dev_get(dev);
5088 		if (idev) {
5089 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
5090 			idev->cnf.disable_ipv6 = newf;
5091 			if (changed)
5092 				dev_disable_change(idev);
5093 		}
5094 	}
5095 	rcu_read_unlock();
5096 }
5097 
5098 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
5099 {
5100 	struct net *net;
5101 	int old;
5102 
5103 	if (!rtnl_trylock())
5104 		return restart_syscall();
5105 
5106 	net = (struct net *)table->extra2;
5107 	old = *p;
5108 	*p = newf;
5109 
5110 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
5111 		rtnl_unlock();
5112 		return 0;
5113 	}
5114 
5115 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
5116 		net->ipv6.devconf_dflt->disable_ipv6 = newf;
5117 		addrconf_disable_change(net, newf);
5118 	} else if ((!newf) ^ (!old))
5119 		dev_disable_change((struct inet6_dev *)table->extra1);
5120 
5121 	rtnl_unlock();
5122 	return 0;
5123 }
5124 
5125 static
5126 int addrconf_sysctl_disable(struct ctl_table *ctl, int write,
5127 			    void __user *buffer, size_t *lenp, loff_t *ppos)
5128 {
5129 	int *valp = ctl->data;
5130 	int val = *valp;
5131 	loff_t pos = *ppos;
5132 	struct ctl_table lctl;
5133 	int ret;
5134 
5135 	/*
5136 	 * ctl->data points to idev->cnf.disable_ipv6, we should
5137 	 * not modify it until we get the rtnl lock.
5138 	 */
5139 	lctl = *ctl;
5140 	lctl.data = &val;
5141 
5142 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5143 
5144 	if (write)
5145 		ret = addrconf_disable_ipv6(ctl, valp, val);
5146 	if (ret)
5147 		*ppos = pos;
5148 	return ret;
5149 }
5150 
5151 static
5152 int addrconf_sysctl_proxy_ndp(struct ctl_table *ctl, int write,
5153 			      void __user *buffer, size_t *lenp, loff_t *ppos)
5154 {
5155 	int *valp = ctl->data;
5156 	int ret;
5157 	int old, new;
5158 
5159 	old = *valp;
5160 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
5161 	new = *valp;
5162 
5163 	if (write && old != new) {
5164 		struct net *net = ctl->extra2;
5165 
5166 		if (!rtnl_trylock())
5167 			return restart_syscall();
5168 
5169 		if (valp == &net->ipv6.devconf_dflt->proxy_ndp)
5170 			inet6_netconf_notify_devconf(net, NETCONFA_PROXY_NEIGH,
5171 						     NETCONFA_IFINDEX_DEFAULT,
5172 						     net->ipv6.devconf_dflt);
5173 		else if (valp == &net->ipv6.devconf_all->proxy_ndp)
5174 			inet6_netconf_notify_devconf(net, NETCONFA_PROXY_NEIGH,
5175 						     NETCONFA_IFINDEX_ALL,
5176 						     net->ipv6.devconf_all);
5177 		else {
5178 			struct inet6_dev *idev = ctl->extra1;
5179 
5180 			inet6_netconf_notify_devconf(net, NETCONFA_PROXY_NEIGH,
5181 						     idev->dev->ifindex,
5182 						     &idev->cnf);
5183 		}
5184 		rtnl_unlock();
5185 	}
5186 
5187 	return ret;
5188 }
5189 
5190 static int addrconf_sysctl_stable_secret(struct ctl_table *ctl, int write,
5191 					 void __user *buffer, size_t *lenp,
5192 					 loff_t *ppos)
5193 {
5194 	int err;
5195 	struct in6_addr addr;
5196 	char str[IPV6_MAX_STRLEN];
5197 	struct ctl_table lctl = *ctl;
5198 	struct net *net = ctl->extra2;
5199 	struct ipv6_stable_secret *secret = ctl->data;
5200 
5201 	if (&net->ipv6.devconf_all->stable_secret == ctl->data)
5202 		return -EIO;
5203 
5204 	lctl.maxlen = IPV6_MAX_STRLEN;
5205 	lctl.data = str;
5206 
5207 	if (!rtnl_trylock())
5208 		return restart_syscall();
5209 
5210 	if (!write && !secret->initialized) {
5211 		err = -EIO;
5212 		goto out;
5213 	}
5214 
5215 	if (!write) {
5216 		err = snprintf(str, sizeof(str), "%pI6",
5217 			       &secret->secret);
5218 		if (err >= sizeof(str)) {
5219 			err = -EIO;
5220 			goto out;
5221 		}
5222 	}
5223 
5224 	err = proc_dostring(&lctl, write, buffer, lenp, ppos);
5225 	if (err || !write)
5226 		goto out;
5227 
5228 	if (in6_pton(str, -1, addr.in6_u.u6_addr8, -1, NULL) != 1) {
5229 		err = -EIO;
5230 		goto out;
5231 	}
5232 
5233 	secret->initialized = true;
5234 	secret->secret = addr;
5235 
5236 	if (&net->ipv6.devconf_dflt->stable_secret == ctl->data) {
5237 		struct net_device *dev;
5238 
5239 		for_each_netdev(net, dev) {
5240 			struct inet6_dev *idev = __in6_dev_get(dev);
5241 
5242 			if (idev) {
5243 				idev->addr_gen_mode =
5244 					IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
5245 			}
5246 		}
5247 	} else {
5248 		struct inet6_dev *idev = ctl->extra1;
5249 
5250 		idev->addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
5251 	}
5252 
5253 out:
5254 	rtnl_unlock();
5255 
5256 	return err;
5257 }
5258 
5259 static struct addrconf_sysctl_table
5260 {
5261 	struct ctl_table_header *sysctl_header;
5262 	struct ctl_table addrconf_vars[DEVCONF_MAX+1];
5263 } addrconf_sysctl __read_mostly = {
5264 	.sysctl_header = NULL,
5265 	.addrconf_vars = {
5266 		{
5267 			.procname	= "forwarding",
5268 			.data		= &ipv6_devconf.forwarding,
5269 			.maxlen		= sizeof(int),
5270 			.mode		= 0644,
5271 			.proc_handler	= addrconf_sysctl_forward,
5272 		},
5273 		{
5274 			.procname	= "hop_limit",
5275 			.data		= &ipv6_devconf.hop_limit,
5276 			.maxlen		= sizeof(int),
5277 			.mode		= 0644,
5278 			.proc_handler	= proc_dointvec,
5279 		},
5280 		{
5281 			.procname	= "mtu",
5282 			.data		= &ipv6_devconf.mtu6,
5283 			.maxlen		= sizeof(int),
5284 			.mode		= 0644,
5285 			.proc_handler	= addrconf_sysctl_mtu,
5286 		},
5287 		{
5288 			.procname	= "accept_ra",
5289 			.data		= &ipv6_devconf.accept_ra,
5290 			.maxlen		= sizeof(int),
5291 			.mode		= 0644,
5292 			.proc_handler	= proc_dointvec,
5293 		},
5294 		{
5295 			.procname	= "accept_redirects",
5296 			.data		= &ipv6_devconf.accept_redirects,
5297 			.maxlen		= sizeof(int),
5298 			.mode		= 0644,
5299 			.proc_handler	= proc_dointvec,
5300 		},
5301 		{
5302 			.procname	= "autoconf",
5303 			.data		= &ipv6_devconf.autoconf,
5304 			.maxlen		= sizeof(int),
5305 			.mode		= 0644,
5306 			.proc_handler	= proc_dointvec,
5307 		},
5308 		{
5309 			.procname	= "dad_transmits",
5310 			.data		= &ipv6_devconf.dad_transmits,
5311 			.maxlen		= sizeof(int),
5312 			.mode		= 0644,
5313 			.proc_handler	= proc_dointvec,
5314 		},
5315 		{
5316 			.procname	= "router_solicitations",
5317 			.data		= &ipv6_devconf.rtr_solicits,
5318 			.maxlen		= sizeof(int),
5319 			.mode		= 0644,
5320 			.proc_handler	= proc_dointvec,
5321 		},
5322 		{
5323 			.procname	= "router_solicitation_interval",
5324 			.data		= &ipv6_devconf.rtr_solicit_interval,
5325 			.maxlen		= sizeof(int),
5326 			.mode		= 0644,
5327 			.proc_handler	= proc_dointvec_jiffies,
5328 		},
5329 		{
5330 			.procname	= "router_solicitation_delay",
5331 			.data		= &ipv6_devconf.rtr_solicit_delay,
5332 			.maxlen		= sizeof(int),
5333 			.mode		= 0644,
5334 			.proc_handler	= proc_dointvec_jiffies,
5335 		},
5336 		{
5337 			.procname	= "force_mld_version",
5338 			.data		= &ipv6_devconf.force_mld_version,
5339 			.maxlen		= sizeof(int),
5340 			.mode		= 0644,
5341 			.proc_handler	= proc_dointvec,
5342 		},
5343 		{
5344 			.procname	= "mldv1_unsolicited_report_interval",
5345 			.data		=
5346 				&ipv6_devconf.mldv1_unsolicited_report_interval,
5347 			.maxlen		= sizeof(int),
5348 			.mode		= 0644,
5349 			.proc_handler	= proc_dointvec_ms_jiffies,
5350 		},
5351 		{
5352 			.procname	= "mldv2_unsolicited_report_interval",
5353 			.data		=
5354 				&ipv6_devconf.mldv2_unsolicited_report_interval,
5355 			.maxlen		= sizeof(int),
5356 			.mode		= 0644,
5357 			.proc_handler	= proc_dointvec_ms_jiffies,
5358 		},
5359 		{
5360 			.procname	= "use_tempaddr",
5361 			.data		= &ipv6_devconf.use_tempaddr,
5362 			.maxlen		= sizeof(int),
5363 			.mode		= 0644,
5364 			.proc_handler	= proc_dointvec,
5365 		},
5366 		{
5367 			.procname	= "temp_valid_lft",
5368 			.data		= &ipv6_devconf.temp_valid_lft,
5369 			.maxlen		= sizeof(int),
5370 			.mode		= 0644,
5371 			.proc_handler	= proc_dointvec,
5372 		},
5373 		{
5374 			.procname	= "temp_prefered_lft",
5375 			.data		= &ipv6_devconf.temp_prefered_lft,
5376 			.maxlen		= sizeof(int),
5377 			.mode		= 0644,
5378 			.proc_handler	= proc_dointvec,
5379 		},
5380 		{
5381 			.procname	= "regen_max_retry",
5382 			.data		= &ipv6_devconf.regen_max_retry,
5383 			.maxlen		= sizeof(int),
5384 			.mode		= 0644,
5385 			.proc_handler	= proc_dointvec,
5386 		},
5387 		{
5388 			.procname	= "max_desync_factor",
5389 			.data		= &ipv6_devconf.max_desync_factor,
5390 			.maxlen		= sizeof(int),
5391 			.mode		= 0644,
5392 			.proc_handler	= proc_dointvec,
5393 		},
5394 		{
5395 			.procname	= "max_addresses",
5396 			.data		= &ipv6_devconf.max_addresses,
5397 			.maxlen		= sizeof(int),
5398 			.mode		= 0644,
5399 			.proc_handler	= proc_dointvec,
5400 		},
5401 		{
5402 			.procname	= "accept_ra_defrtr",
5403 			.data		= &ipv6_devconf.accept_ra_defrtr,
5404 			.maxlen		= sizeof(int),
5405 			.mode		= 0644,
5406 			.proc_handler	= proc_dointvec,
5407 		},
5408 		{
5409 			.procname	= "accept_ra_pinfo",
5410 			.data		= &ipv6_devconf.accept_ra_pinfo,
5411 			.maxlen		= sizeof(int),
5412 			.mode		= 0644,
5413 			.proc_handler	= proc_dointvec,
5414 		},
5415 #ifdef CONFIG_IPV6_ROUTER_PREF
5416 		{
5417 			.procname	= "accept_ra_rtr_pref",
5418 			.data		= &ipv6_devconf.accept_ra_rtr_pref,
5419 			.maxlen		= sizeof(int),
5420 			.mode		= 0644,
5421 			.proc_handler	= proc_dointvec,
5422 		},
5423 		{
5424 			.procname	= "router_probe_interval",
5425 			.data		= &ipv6_devconf.rtr_probe_interval,
5426 			.maxlen		= sizeof(int),
5427 			.mode		= 0644,
5428 			.proc_handler	= proc_dointvec_jiffies,
5429 		},
5430 #ifdef CONFIG_IPV6_ROUTE_INFO
5431 		{
5432 			.procname	= "accept_ra_rt_info_max_plen",
5433 			.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
5434 			.maxlen		= sizeof(int),
5435 			.mode		= 0644,
5436 			.proc_handler	= proc_dointvec,
5437 		},
5438 #endif
5439 #endif
5440 		{
5441 			.procname	= "proxy_ndp",
5442 			.data		= &ipv6_devconf.proxy_ndp,
5443 			.maxlen		= sizeof(int),
5444 			.mode		= 0644,
5445 			.proc_handler	= addrconf_sysctl_proxy_ndp,
5446 		},
5447 		{
5448 			.procname	= "accept_source_route",
5449 			.data		= &ipv6_devconf.accept_source_route,
5450 			.maxlen		= sizeof(int),
5451 			.mode		= 0644,
5452 			.proc_handler	= proc_dointvec,
5453 		},
5454 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
5455 		{
5456 			.procname       = "optimistic_dad",
5457 			.data           = &ipv6_devconf.optimistic_dad,
5458 			.maxlen         = sizeof(int),
5459 			.mode           = 0644,
5460 			.proc_handler   = proc_dointvec,
5461 
5462 		},
5463 		{
5464 			.procname       = "use_optimistic",
5465 			.data           = &ipv6_devconf.use_optimistic,
5466 			.maxlen         = sizeof(int),
5467 			.mode           = 0644,
5468 			.proc_handler   = proc_dointvec,
5469 
5470 		},
5471 #endif
5472 #ifdef CONFIG_IPV6_MROUTE
5473 		{
5474 			.procname	= "mc_forwarding",
5475 			.data		= &ipv6_devconf.mc_forwarding,
5476 			.maxlen		= sizeof(int),
5477 			.mode		= 0444,
5478 			.proc_handler	= proc_dointvec,
5479 		},
5480 #endif
5481 		{
5482 			.procname	= "disable_ipv6",
5483 			.data		= &ipv6_devconf.disable_ipv6,
5484 			.maxlen		= sizeof(int),
5485 			.mode		= 0644,
5486 			.proc_handler	= addrconf_sysctl_disable,
5487 		},
5488 		{
5489 			.procname	= "accept_dad",
5490 			.data		= &ipv6_devconf.accept_dad,
5491 			.maxlen		= sizeof(int),
5492 			.mode		= 0644,
5493 			.proc_handler	= proc_dointvec,
5494 		},
5495 		{
5496 			.procname       = "force_tllao",
5497 			.data           = &ipv6_devconf.force_tllao,
5498 			.maxlen         = sizeof(int),
5499 			.mode           = 0644,
5500 			.proc_handler   = proc_dointvec
5501 		},
5502 		{
5503 			.procname       = "ndisc_notify",
5504 			.data           = &ipv6_devconf.ndisc_notify,
5505 			.maxlen         = sizeof(int),
5506 			.mode           = 0644,
5507 			.proc_handler   = proc_dointvec
5508 		},
5509 		{
5510 			.procname	= "suppress_frag_ndisc",
5511 			.data		= &ipv6_devconf.suppress_frag_ndisc,
5512 			.maxlen		= sizeof(int),
5513 			.mode		= 0644,
5514 			.proc_handler	= proc_dointvec
5515 		},
5516 		{
5517 			.procname	= "accept_ra_from_local",
5518 			.data		= &ipv6_devconf.accept_ra_from_local,
5519 			.maxlen		= sizeof(int),
5520 			.mode		= 0644,
5521 			.proc_handler	= proc_dointvec,
5522 		},
5523 		{
5524 			.procname	= "accept_ra_mtu",
5525 			.data		= &ipv6_devconf.accept_ra_mtu,
5526 			.maxlen		= sizeof(int),
5527 			.mode		= 0644,
5528 			.proc_handler	= proc_dointvec,
5529 		},
5530 		{
5531 			.procname	= "stable_secret",
5532 			.data		= &ipv6_devconf.stable_secret,
5533 			.maxlen		= IPV6_MAX_STRLEN,
5534 			.mode		= 0600,
5535 			.proc_handler	= addrconf_sysctl_stable_secret,
5536 		},
5537 		{
5538 			/* sentinel */
5539 		}
5540 	},
5541 };
5542 
5543 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
5544 		struct inet6_dev *idev, struct ipv6_devconf *p)
5545 {
5546 	int i;
5547 	struct addrconf_sysctl_table *t;
5548 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
5549 
5550 	t = kmemdup(&addrconf_sysctl, sizeof(*t), GFP_KERNEL);
5551 	if (t == NULL)
5552 		goto out;
5553 
5554 	for (i = 0; t->addrconf_vars[i].data; i++) {
5555 		t->addrconf_vars[i].data += (char *)p - (char *)&ipv6_devconf;
5556 		t->addrconf_vars[i].extra1 = idev; /* embedded; no ref */
5557 		t->addrconf_vars[i].extra2 = net;
5558 	}
5559 
5560 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
5561 
5562 	t->sysctl_header = register_net_sysctl(net, path, t->addrconf_vars);
5563 	if (t->sysctl_header == NULL)
5564 		goto free;
5565 
5566 	p->sysctl = t;
5567 	return 0;
5568 
5569 free:
5570 	kfree(t);
5571 out:
5572 	return -ENOBUFS;
5573 }
5574 
5575 static void __addrconf_sysctl_unregister(struct ipv6_devconf *p)
5576 {
5577 	struct addrconf_sysctl_table *t;
5578 
5579 	if (p->sysctl == NULL)
5580 		return;
5581 
5582 	t = p->sysctl;
5583 	p->sysctl = NULL;
5584 	unregister_net_sysctl_table(t->sysctl_header);
5585 	kfree(t);
5586 }
5587 
5588 static int addrconf_sysctl_register(struct inet6_dev *idev)
5589 {
5590 	int err;
5591 
5592 	if (!sysctl_dev_name_is_allowed(idev->dev->name))
5593 		return -EINVAL;
5594 
5595 	err = neigh_sysctl_register(idev->dev, idev->nd_parms,
5596 				    &ndisc_ifinfo_sysctl_change);
5597 	if (err)
5598 		return err;
5599 	err = __addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
5600 					 idev, &idev->cnf);
5601 	if (err)
5602 		neigh_sysctl_unregister(idev->nd_parms);
5603 
5604 	return err;
5605 }
5606 
5607 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
5608 {
5609 	__addrconf_sysctl_unregister(&idev->cnf);
5610 	neigh_sysctl_unregister(idev->nd_parms);
5611 }
5612 
5613 
5614 #endif
5615 
5616 static int __net_init addrconf_init_net(struct net *net)
5617 {
5618 	int err = -ENOMEM;
5619 	struct ipv6_devconf *all, *dflt;
5620 
5621 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
5622 	if (all == NULL)
5623 		goto err_alloc_all;
5624 
5625 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
5626 	if (dflt == NULL)
5627 		goto err_alloc_dflt;
5628 
5629 	/* these will be inherited by all namespaces */
5630 	dflt->autoconf = ipv6_defaults.autoconf;
5631 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
5632 
5633 	dflt->stable_secret.initialized = false;
5634 	all->stable_secret.initialized = false;
5635 
5636 	net->ipv6.devconf_all = all;
5637 	net->ipv6.devconf_dflt = dflt;
5638 
5639 #ifdef CONFIG_SYSCTL
5640 	err = __addrconf_sysctl_register(net, "all", NULL, all);
5641 	if (err < 0)
5642 		goto err_reg_all;
5643 
5644 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
5645 	if (err < 0)
5646 		goto err_reg_dflt;
5647 #endif
5648 	return 0;
5649 
5650 #ifdef CONFIG_SYSCTL
5651 err_reg_dflt:
5652 	__addrconf_sysctl_unregister(all);
5653 err_reg_all:
5654 	kfree(dflt);
5655 #endif
5656 err_alloc_dflt:
5657 	kfree(all);
5658 err_alloc_all:
5659 	return err;
5660 }
5661 
5662 static void __net_exit addrconf_exit_net(struct net *net)
5663 {
5664 #ifdef CONFIG_SYSCTL
5665 	__addrconf_sysctl_unregister(net->ipv6.devconf_dflt);
5666 	__addrconf_sysctl_unregister(net->ipv6.devconf_all);
5667 #endif
5668 	kfree(net->ipv6.devconf_dflt);
5669 	kfree(net->ipv6.devconf_all);
5670 }
5671 
5672 static struct pernet_operations addrconf_ops = {
5673 	.init = addrconf_init_net,
5674 	.exit = addrconf_exit_net,
5675 };
5676 
5677 static struct rtnl_af_ops inet6_ops __read_mostly = {
5678 	.family		  = AF_INET6,
5679 	.fill_link_af	  = inet6_fill_link_af,
5680 	.get_link_af_size = inet6_get_link_af_size,
5681 	.validate_link_af = inet6_validate_link_af,
5682 	.set_link_af	  = inet6_set_link_af,
5683 };
5684 
5685 /*
5686  *	Init / cleanup code
5687  */
5688 
5689 int __init addrconf_init(void)
5690 {
5691 	struct inet6_dev *idev;
5692 	int i, err;
5693 
5694 	err = ipv6_addr_label_init();
5695 	if (err < 0) {
5696 		pr_crit("%s: cannot initialize default policy table: %d\n",
5697 			__func__, err);
5698 		goto out;
5699 	}
5700 
5701 	err = register_pernet_subsys(&addrconf_ops);
5702 	if (err < 0)
5703 		goto out_addrlabel;
5704 
5705 	addrconf_wq = create_workqueue("ipv6_addrconf");
5706 	if (!addrconf_wq) {
5707 		err = -ENOMEM;
5708 		goto out_nowq;
5709 	}
5710 
5711 	/* The addrconf netdev notifier requires that loopback_dev
5712 	 * has it's ipv6 private information allocated and setup
5713 	 * before it can bring up and give link-local addresses
5714 	 * to other devices which are up.
5715 	 *
5716 	 * Unfortunately, loopback_dev is not necessarily the first
5717 	 * entry in the global dev_base list of net devices.  In fact,
5718 	 * it is likely to be the very last entry on that list.
5719 	 * So this causes the notifier registry below to try and
5720 	 * give link-local addresses to all devices besides loopback_dev
5721 	 * first, then loopback_dev, which cases all the non-loopback_dev
5722 	 * devices to fail to get a link-local address.
5723 	 *
5724 	 * So, as a temporary fix, allocate the ipv6 structure for
5725 	 * loopback_dev first by hand.
5726 	 * Longer term, all of the dependencies ipv6 has upon the loopback
5727 	 * device and it being up should be removed.
5728 	 */
5729 	rtnl_lock();
5730 	idev = ipv6_add_dev(init_net.loopback_dev);
5731 	rtnl_unlock();
5732 	if (IS_ERR(idev)) {
5733 		err = PTR_ERR(idev);
5734 		goto errlo;
5735 	}
5736 
5737 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
5738 		INIT_HLIST_HEAD(&inet6_addr_lst[i]);
5739 
5740 	register_netdevice_notifier(&ipv6_dev_notf);
5741 
5742 	addrconf_verify();
5743 
5744 	rtnl_af_register(&inet6_ops);
5745 
5746 	err = __rtnl_register(PF_INET6, RTM_GETLINK, NULL, inet6_dump_ifinfo,
5747 			      NULL);
5748 	if (err < 0)
5749 		goto errout;
5750 
5751 	/* Only the first call to __rtnl_register can fail */
5752 	__rtnl_register(PF_INET6, RTM_NEWADDR, inet6_rtm_newaddr, NULL, NULL);
5753 	__rtnl_register(PF_INET6, RTM_DELADDR, inet6_rtm_deladdr, NULL, NULL);
5754 	__rtnl_register(PF_INET6, RTM_GETADDR, inet6_rtm_getaddr,
5755 			inet6_dump_ifaddr, NULL);
5756 	__rtnl_register(PF_INET6, RTM_GETMULTICAST, NULL,
5757 			inet6_dump_ifmcaddr, NULL);
5758 	__rtnl_register(PF_INET6, RTM_GETANYCAST, NULL,
5759 			inet6_dump_ifacaddr, NULL);
5760 	__rtnl_register(PF_INET6, RTM_GETNETCONF, inet6_netconf_get_devconf,
5761 			inet6_netconf_dump_devconf, NULL);
5762 
5763 	ipv6_addr_label_rtnl_register();
5764 
5765 	return 0;
5766 errout:
5767 	rtnl_af_unregister(&inet6_ops);
5768 	unregister_netdevice_notifier(&ipv6_dev_notf);
5769 errlo:
5770 	destroy_workqueue(addrconf_wq);
5771 out_nowq:
5772 	unregister_pernet_subsys(&addrconf_ops);
5773 out_addrlabel:
5774 	ipv6_addr_label_cleanup();
5775 out:
5776 	return err;
5777 }
5778 
5779 void addrconf_cleanup(void)
5780 {
5781 	struct net_device *dev;
5782 	int i;
5783 
5784 	unregister_netdevice_notifier(&ipv6_dev_notf);
5785 	unregister_pernet_subsys(&addrconf_ops);
5786 	ipv6_addr_label_cleanup();
5787 
5788 	rtnl_lock();
5789 
5790 	__rtnl_af_unregister(&inet6_ops);
5791 
5792 	/* clean dev list */
5793 	for_each_netdev(&init_net, dev) {
5794 		if (__in6_dev_get(dev) == NULL)
5795 			continue;
5796 		addrconf_ifdown(dev, 1);
5797 	}
5798 	addrconf_ifdown(init_net.loopback_dev, 2);
5799 
5800 	/*
5801 	 *	Check hash table.
5802 	 */
5803 	spin_lock_bh(&addrconf_hash_lock);
5804 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
5805 		WARN_ON(!hlist_empty(&inet6_addr_lst[i]));
5806 	spin_unlock_bh(&addrconf_hash_lock);
5807 	cancel_delayed_work(&addr_chk_work);
5808 	rtnl_unlock();
5809 
5810 	destroy_workqueue(addrconf_wq);
5811 }
5812