xref: /openbmc/linux/net/ipv6/addrconf.c (revision 930beb5a)
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/in6.h>
50 #include <linux/netdevice.h>
51 #include <linux/if_addr.h>
52 #include <linux/if_arp.h>
53 #include <linux/if_arcnet.h>
54 #include <linux/if_infiniband.h>
55 #include <linux/route.h>
56 #include <linux/inetdevice.h>
57 #include <linux/init.h>
58 #include <linux/slab.h>
59 #ifdef CONFIG_SYSCTL
60 #include <linux/sysctl.h>
61 #endif
62 #include <linux/capability.h>
63 #include <linux/delay.h>
64 #include <linux/notifier.h>
65 #include <linux/string.h>
66 #include <linux/hash.h>
67 
68 #include <net/net_namespace.h>
69 #include <net/sock.h>
70 #include <net/snmp.h>
71 
72 #include <net/af_ieee802154.h>
73 #include <net/firewire.h>
74 #include <net/ipv6.h>
75 #include <net/protocol.h>
76 #include <net/ndisc.h>
77 #include <net/ip6_route.h>
78 #include <net/addrconf.h>
79 #include <net/tcp.h>
80 #include <net/ip.h>
81 #include <net/netlink.h>
82 #include <net/pkt_sched.h>
83 #include <linux/if_tunnel.h>
84 #include <linux/rtnetlink.h>
85 #include <linux/netconf.h>
86 #include <linux/random.h>
87 #include <linux/uaccess.h>
88 #include <asm/unaligned.h>
89 
90 #include <linux/proc_fs.h>
91 #include <linux/seq_file.h>
92 #include <linux/export.h>
93 
94 /* Set to 3 to get tracing... */
95 #define ACONF_DEBUG 2
96 
97 #if ACONF_DEBUG >= 3
98 #define ADBG(fmt, ...) printk(fmt, ##__VA_ARGS__)
99 #else
100 #define ADBG(fmt, ...) do { if (0) printk(fmt, ##__VA_ARGS__); } while (0)
101 #endif
102 
103 #define	INFINITY_LIFE_TIME	0xFFFFFFFF
104 
105 static inline u32 cstamp_delta(unsigned long cstamp)
106 {
107 	return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
108 }
109 
110 #ifdef CONFIG_SYSCTL
111 static void addrconf_sysctl_register(struct inet6_dev *idev);
112 static void addrconf_sysctl_unregister(struct inet6_dev *idev);
113 #else
114 static inline void addrconf_sysctl_register(struct inet6_dev *idev)
115 {
116 }
117 
118 static inline void addrconf_sysctl_unregister(struct inet6_dev *idev)
119 {
120 }
121 #endif
122 
123 static void __ipv6_regen_rndid(struct inet6_dev *idev);
124 static void __ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr);
125 static void ipv6_regen_rndid(unsigned long data);
126 
127 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev);
128 static int ipv6_count_addresses(struct inet6_dev *idev);
129 
130 /*
131  *	Configured unicast address hash table
132  */
133 static struct hlist_head inet6_addr_lst[IN6_ADDR_HSIZE];
134 static DEFINE_SPINLOCK(addrconf_hash_lock);
135 
136 static void addrconf_verify(unsigned long);
137 
138 static DEFINE_TIMER(addr_chk_timer, addrconf_verify, 0, 0);
139 static DEFINE_SPINLOCK(addrconf_verify_lock);
140 
141 static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
142 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
143 
144 static void addrconf_type_change(struct net_device *dev,
145 				 unsigned long event);
146 static int addrconf_ifdown(struct net_device *dev, int how);
147 
148 static struct rt6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
149 						  int plen,
150 						  const struct net_device *dev,
151 						  u32 flags, u32 noflags);
152 
153 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
154 static void addrconf_dad_timer(unsigned long data);
155 static void addrconf_dad_completed(struct inet6_ifaddr *ifp);
156 static void addrconf_dad_run(struct inet6_dev *idev);
157 static void addrconf_rs_timer(unsigned long data);
158 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
159 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
160 
161 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
162 				struct prefix_info *pinfo);
163 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
164 			       struct net_device *dev);
165 
166 static struct ipv6_devconf ipv6_devconf __read_mostly = {
167 	.forwarding		= 0,
168 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
169 	.mtu6			= IPV6_MIN_MTU,
170 	.accept_ra		= 1,
171 	.accept_redirects	= 1,
172 	.autoconf		= 1,
173 	.force_mld_version	= 0,
174 	.mldv1_unsolicited_report_interval = 10 * HZ,
175 	.mldv2_unsolicited_report_interval = HZ,
176 	.dad_transmits		= 1,
177 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
178 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
179 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
180 	.use_tempaddr 		= 0,
181 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
182 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
183 	.regen_max_retry	= REGEN_MAX_RETRY,
184 	.max_desync_factor	= MAX_DESYNC_FACTOR,
185 	.max_addresses		= IPV6_MAX_ADDRESSES,
186 	.accept_ra_defrtr	= 1,
187 	.accept_ra_pinfo	= 1,
188 #ifdef CONFIG_IPV6_ROUTER_PREF
189 	.accept_ra_rtr_pref	= 1,
190 	.rtr_probe_interval	= 60 * HZ,
191 #ifdef CONFIG_IPV6_ROUTE_INFO
192 	.accept_ra_rt_info_max_plen = 0,
193 #endif
194 #endif
195 	.proxy_ndp		= 0,
196 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
197 	.disable_ipv6		= 0,
198 	.accept_dad		= 1,
199 	.suppress_frag_ndisc	= 1,
200 };
201 
202 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
203 	.forwarding		= 0,
204 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
205 	.mtu6			= IPV6_MIN_MTU,
206 	.accept_ra		= 1,
207 	.accept_redirects	= 1,
208 	.autoconf		= 1,
209 	.force_mld_version	= 0,
210 	.mldv1_unsolicited_report_interval = 10 * HZ,
211 	.mldv2_unsolicited_report_interval = HZ,
212 	.dad_transmits		= 1,
213 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
214 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
215 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
216 	.use_tempaddr		= 0,
217 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
218 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
219 	.regen_max_retry	= REGEN_MAX_RETRY,
220 	.max_desync_factor	= MAX_DESYNC_FACTOR,
221 	.max_addresses		= IPV6_MAX_ADDRESSES,
222 	.accept_ra_defrtr	= 1,
223 	.accept_ra_pinfo	= 1,
224 #ifdef CONFIG_IPV6_ROUTER_PREF
225 	.accept_ra_rtr_pref	= 1,
226 	.rtr_probe_interval	= 60 * HZ,
227 #ifdef CONFIG_IPV6_ROUTE_INFO
228 	.accept_ra_rt_info_max_plen = 0,
229 #endif
230 #endif
231 	.proxy_ndp		= 0,
232 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
233 	.disable_ipv6		= 0,
234 	.accept_dad		= 1,
235 	.suppress_frag_ndisc	= 1,
236 };
237 
238 /* Check if a valid qdisc is available */
239 static inline bool addrconf_qdisc_ok(const struct net_device *dev)
240 {
241 	return !qdisc_tx_is_noop(dev);
242 }
243 
244 static void addrconf_del_rs_timer(struct inet6_dev *idev)
245 {
246 	if (del_timer(&idev->rs_timer))
247 		__in6_dev_put(idev);
248 }
249 
250 static void addrconf_del_dad_timer(struct inet6_ifaddr *ifp)
251 {
252 	if (del_timer(&ifp->dad_timer))
253 		__in6_ifa_put(ifp);
254 }
255 
256 static void addrconf_mod_rs_timer(struct inet6_dev *idev,
257 				  unsigned long when)
258 {
259 	if (!timer_pending(&idev->rs_timer))
260 		in6_dev_hold(idev);
261 	mod_timer(&idev->rs_timer, jiffies + when);
262 }
263 
264 static void addrconf_mod_dad_timer(struct inet6_ifaddr *ifp,
265 				   unsigned long when)
266 {
267 	if (!timer_pending(&ifp->dad_timer))
268 		in6_ifa_hold(ifp);
269 	mod_timer(&ifp->dad_timer, jiffies + when);
270 }
271 
272 static int snmp6_alloc_dev(struct inet6_dev *idev)
273 {
274 	int i;
275 
276 	if (snmp_mib_init((void __percpu **)idev->stats.ipv6,
277 			  sizeof(struct ipstats_mib),
278 			  __alignof__(struct ipstats_mib)) < 0)
279 		goto err_ip;
280 
281 	for_each_possible_cpu(i) {
282 		struct ipstats_mib *addrconf_stats;
283 		addrconf_stats = per_cpu_ptr(idev->stats.ipv6[0], i);
284 		u64_stats_init(&addrconf_stats->syncp);
285 #if SNMP_ARRAY_SZ == 2
286 		addrconf_stats = per_cpu_ptr(idev->stats.ipv6[1], i);
287 		u64_stats_init(&addrconf_stats->syncp);
288 #endif
289 	}
290 
291 
292 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
293 					GFP_KERNEL);
294 	if (!idev->stats.icmpv6dev)
295 		goto err_icmp;
296 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
297 					   GFP_KERNEL);
298 	if (!idev->stats.icmpv6msgdev)
299 		goto err_icmpmsg;
300 
301 	return 0;
302 
303 err_icmpmsg:
304 	kfree(idev->stats.icmpv6dev);
305 err_icmp:
306 	snmp_mib_free((void __percpu **)idev->stats.ipv6);
307 err_ip:
308 	return -ENOMEM;
309 }
310 
311 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
312 {
313 	struct inet6_dev *ndev;
314 
315 	ASSERT_RTNL();
316 
317 	if (dev->mtu < IPV6_MIN_MTU)
318 		return NULL;
319 
320 	ndev = kzalloc(sizeof(struct inet6_dev), GFP_KERNEL);
321 
322 	if (ndev == NULL)
323 		return NULL;
324 
325 	rwlock_init(&ndev->lock);
326 	ndev->dev = dev;
327 	INIT_LIST_HEAD(&ndev->addr_list);
328 	setup_timer(&ndev->rs_timer, addrconf_rs_timer,
329 		    (unsigned long)ndev);
330 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
331 	ndev->cnf.mtu6 = dev->mtu;
332 	ndev->cnf.sysctl = NULL;
333 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
334 	if (ndev->nd_parms == NULL) {
335 		kfree(ndev);
336 		return NULL;
337 	}
338 	if (ndev->cnf.forwarding)
339 		dev_disable_lro(dev);
340 	/* We refer to the device */
341 	dev_hold(dev);
342 
343 	if (snmp6_alloc_dev(ndev) < 0) {
344 		ADBG(KERN_WARNING
345 			"%s: cannot allocate memory for statistics; dev=%s.\n",
346 			__func__, dev->name);
347 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
348 		dev_put(dev);
349 		kfree(ndev);
350 		return NULL;
351 	}
352 
353 	if (snmp6_register_dev(ndev) < 0) {
354 		ADBG(KERN_WARNING
355 			"%s: cannot create /proc/net/dev_snmp6/%s\n",
356 			__func__, dev->name);
357 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
358 		ndev->dead = 1;
359 		in6_dev_finish_destroy(ndev);
360 		return NULL;
361 	}
362 
363 	/* One reference from device.  We must do this before
364 	 * we invoke __ipv6_regen_rndid().
365 	 */
366 	in6_dev_hold(ndev);
367 
368 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
369 		ndev->cnf.accept_dad = -1;
370 
371 #if IS_ENABLED(CONFIG_IPV6_SIT)
372 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
373 		pr_info("%s: Disabled Multicast RS\n", dev->name);
374 		ndev->cnf.rtr_solicits = 0;
375 	}
376 #endif
377 
378 	INIT_LIST_HEAD(&ndev->tempaddr_list);
379 	setup_timer(&ndev->regen_timer, ipv6_regen_rndid, (unsigned long)ndev);
380 	if ((dev->flags&IFF_LOOPBACK) ||
381 	    dev->type == ARPHRD_TUNNEL ||
382 	    dev->type == ARPHRD_TUNNEL6 ||
383 	    dev->type == ARPHRD_SIT ||
384 	    dev->type == ARPHRD_NONE) {
385 		ndev->cnf.use_tempaddr = -1;
386 	} else {
387 		in6_dev_hold(ndev);
388 		ipv6_regen_rndid((unsigned long) ndev);
389 	}
390 
391 	ndev->token = in6addr_any;
392 
393 	if (netif_running(dev) && addrconf_qdisc_ok(dev))
394 		ndev->if_flags |= IF_READY;
395 
396 	ipv6_mc_init_dev(ndev);
397 	ndev->tstamp = jiffies;
398 	addrconf_sysctl_register(ndev);
399 	/* protected by rtnl_lock */
400 	rcu_assign_pointer(dev->ip6_ptr, ndev);
401 
402 	/* Join interface-local all-node multicast group */
403 	ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes);
404 
405 	/* Join all-node multicast group */
406 	ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
407 
408 	/* Join all-router multicast group if forwarding is set */
409 	if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
410 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
411 
412 	return ndev;
413 }
414 
415 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
416 {
417 	struct inet6_dev *idev;
418 
419 	ASSERT_RTNL();
420 
421 	idev = __in6_dev_get(dev);
422 	if (!idev) {
423 		idev = ipv6_add_dev(dev);
424 		if (!idev)
425 			return NULL;
426 	}
427 
428 	if (dev->flags&IFF_UP)
429 		ipv6_mc_up(idev);
430 	return idev;
431 }
432 
433 static int inet6_netconf_msgsize_devconf(int type)
434 {
435 	int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
436 		    + nla_total_size(4);	/* NETCONFA_IFINDEX */
437 
438 	/* type -1 is used for ALL */
439 	if (type == -1 || type == NETCONFA_FORWARDING)
440 		size += nla_total_size(4);
441 #ifdef CONFIG_IPV6_MROUTE
442 	if (type == -1 || type == NETCONFA_MC_FORWARDING)
443 		size += nla_total_size(4);
444 #endif
445 
446 	return size;
447 }
448 
449 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
450 				      struct ipv6_devconf *devconf, u32 portid,
451 				      u32 seq, int event, unsigned int flags,
452 				      int type)
453 {
454 	struct nlmsghdr  *nlh;
455 	struct netconfmsg *ncm;
456 
457 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
458 			flags);
459 	if (nlh == NULL)
460 		return -EMSGSIZE;
461 
462 	ncm = nlmsg_data(nlh);
463 	ncm->ncm_family = AF_INET6;
464 
465 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
466 		goto nla_put_failure;
467 
468 	/* type -1 is used for ALL */
469 	if ((type == -1 || type == NETCONFA_FORWARDING) &&
470 	    nla_put_s32(skb, NETCONFA_FORWARDING, devconf->forwarding) < 0)
471 		goto nla_put_failure;
472 #ifdef CONFIG_IPV6_MROUTE
473 	if ((type == -1 || type == NETCONFA_MC_FORWARDING) &&
474 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
475 			devconf->mc_forwarding) < 0)
476 		goto nla_put_failure;
477 #endif
478 	return nlmsg_end(skb, nlh);
479 
480 nla_put_failure:
481 	nlmsg_cancel(skb, nlh);
482 	return -EMSGSIZE;
483 }
484 
485 void inet6_netconf_notify_devconf(struct net *net, int type, int ifindex,
486 				  struct ipv6_devconf *devconf)
487 {
488 	struct sk_buff *skb;
489 	int err = -ENOBUFS;
490 
491 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_ATOMIC);
492 	if (skb == NULL)
493 		goto errout;
494 
495 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
496 					 RTM_NEWNETCONF, 0, type);
497 	if (err < 0) {
498 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
499 		WARN_ON(err == -EMSGSIZE);
500 		kfree_skb(skb);
501 		goto errout;
502 	}
503 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_ATOMIC);
504 	return;
505 errout:
506 	rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
507 }
508 
509 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
510 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
511 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
512 };
513 
514 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
515 				     struct nlmsghdr *nlh)
516 {
517 	struct net *net = sock_net(in_skb->sk);
518 	struct nlattr *tb[NETCONFA_MAX+1];
519 	struct netconfmsg *ncm;
520 	struct sk_buff *skb;
521 	struct ipv6_devconf *devconf;
522 	struct inet6_dev *in6_dev;
523 	struct net_device *dev;
524 	int ifindex;
525 	int err;
526 
527 	err = nlmsg_parse(nlh, sizeof(*ncm), tb, NETCONFA_MAX,
528 			  devconf_ipv6_policy);
529 	if (err < 0)
530 		goto errout;
531 
532 	err = EINVAL;
533 	if (!tb[NETCONFA_IFINDEX])
534 		goto errout;
535 
536 	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
537 	switch (ifindex) {
538 	case NETCONFA_IFINDEX_ALL:
539 		devconf = net->ipv6.devconf_all;
540 		break;
541 	case NETCONFA_IFINDEX_DEFAULT:
542 		devconf = net->ipv6.devconf_dflt;
543 		break;
544 	default:
545 		dev = __dev_get_by_index(net, ifindex);
546 		if (dev == NULL)
547 			goto errout;
548 		in6_dev = __in6_dev_get(dev);
549 		if (in6_dev == NULL)
550 			goto errout;
551 		devconf = &in6_dev->cnf;
552 		break;
553 	}
554 
555 	err = -ENOBUFS;
556 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(-1), GFP_ATOMIC);
557 	if (skb == NULL)
558 		goto errout;
559 
560 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
561 					 NETLINK_CB(in_skb).portid,
562 					 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
563 					 -1);
564 	if (err < 0) {
565 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
566 		WARN_ON(err == -EMSGSIZE);
567 		kfree_skb(skb);
568 		goto errout;
569 	}
570 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
571 errout:
572 	return err;
573 }
574 
575 static int inet6_netconf_dump_devconf(struct sk_buff *skb,
576 				      struct netlink_callback *cb)
577 {
578 	struct net *net = sock_net(skb->sk);
579 	int h, s_h;
580 	int idx, s_idx;
581 	struct net_device *dev;
582 	struct inet6_dev *idev;
583 	struct hlist_head *head;
584 
585 	s_h = cb->args[0];
586 	s_idx = idx = cb->args[1];
587 
588 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
589 		idx = 0;
590 		head = &net->dev_index_head[h];
591 		rcu_read_lock();
592 		cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^
593 			  net->dev_base_seq;
594 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
595 			if (idx < s_idx)
596 				goto cont;
597 			idev = __in6_dev_get(dev);
598 			if (!idev)
599 				goto cont;
600 
601 			if (inet6_netconf_fill_devconf(skb, dev->ifindex,
602 						       &idev->cnf,
603 						       NETLINK_CB(cb->skb).portid,
604 						       cb->nlh->nlmsg_seq,
605 						       RTM_NEWNETCONF,
606 						       NLM_F_MULTI,
607 						       -1) <= 0) {
608 				rcu_read_unlock();
609 				goto done;
610 			}
611 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
612 cont:
613 			idx++;
614 		}
615 		rcu_read_unlock();
616 	}
617 	if (h == NETDEV_HASHENTRIES) {
618 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
619 					       net->ipv6.devconf_all,
620 					       NETLINK_CB(cb->skb).portid,
621 					       cb->nlh->nlmsg_seq,
622 					       RTM_NEWNETCONF, NLM_F_MULTI,
623 					       -1) <= 0)
624 			goto done;
625 		else
626 			h++;
627 	}
628 	if (h == NETDEV_HASHENTRIES + 1) {
629 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
630 					       net->ipv6.devconf_dflt,
631 					       NETLINK_CB(cb->skb).portid,
632 					       cb->nlh->nlmsg_seq,
633 					       RTM_NEWNETCONF, NLM_F_MULTI,
634 					       -1) <= 0)
635 			goto done;
636 		else
637 			h++;
638 	}
639 done:
640 	cb->args[0] = h;
641 	cb->args[1] = idx;
642 
643 	return skb->len;
644 }
645 
646 #ifdef CONFIG_SYSCTL
647 static void dev_forward_change(struct inet6_dev *idev)
648 {
649 	struct net_device *dev;
650 	struct inet6_ifaddr *ifa;
651 
652 	if (!idev)
653 		return;
654 	dev = idev->dev;
655 	if (idev->cnf.forwarding)
656 		dev_disable_lro(dev);
657 	if (dev->flags & IFF_MULTICAST) {
658 		if (idev->cnf.forwarding) {
659 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
660 			ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
661 			ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters);
662 		} else {
663 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
664 			ipv6_dev_mc_dec(dev, &in6addr_interfacelocal_allrouters);
665 			ipv6_dev_mc_dec(dev, &in6addr_sitelocal_allrouters);
666 		}
667 	}
668 
669 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
670 		if (ifa->flags&IFA_F_TENTATIVE)
671 			continue;
672 		if (idev->cnf.forwarding)
673 			addrconf_join_anycast(ifa);
674 		else
675 			addrconf_leave_anycast(ifa);
676 	}
677 	inet6_netconf_notify_devconf(dev_net(dev), NETCONFA_FORWARDING,
678 				     dev->ifindex, &idev->cnf);
679 }
680 
681 
682 static void addrconf_forward_change(struct net *net, __s32 newf)
683 {
684 	struct net_device *dev;
685 	struct inet6_dev *idev;
686 
687 	for_each_netdev(net, dev) {
688 		idev = __in6_dev_get(dev);
689 		if (idev) {
690 			int changed = (!idev->cnf.forwarding) ^ (!newf);
691 			idev->cnf.forwarding = newf;
692 			if (changed)
693 				dev_forward_change(idev);
694 		}
695 	}
696 }
697 
698 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int newf)
699 {
700 	struct net *net;
701 	int old;
702 
703 	if (!rtnl_trylock())
704 		return restart_syscall();
705 
706 	net = (struct net *)table->extra2;
707 	old = *p;
708 	*p = newf;
709 
710 	if (p == &net->ipv6.devconf_dflt->forwarding) {
711 		if ((!newf) ^ (!old))
712 			inet6_netconf_notify_devconf(net, NETCONFA_FORWARDING,
713 						     NETCONFA_IFINDEX_DEFAULT,
714 						     net->ipv6.devconf_dflt);
715 		rtnl_unlock();
716 		return 0;
717 	}
718 
719 	if (p == &net->ipv6.devconf_all->forwarding) {
720 		net->ipv6.devconf_dflt->forwarding = newf;
721 		addrconf_forward_change(net, newf);
722 		if ((!newf) ^ (!old))
723 			inet6_netconf_notify_devconf(net, NETCONFA_FORWARDING,
724 						     NETCONFA_IFINDEX_ALL,
725 						     net->ipv6.devconf_all);
726 	} else if ((!newf) ^ (!old))
727 		dev_forward_change((struct inet6_dev *)table->extra1);
728 	rtnl_unlock();
729 
730 	if (newf)
731 		rt6_purge_dflt_routers(net);
732 	return 1;
733 }
734 #endif
735 
736 /* Nobody refers to this ifaddr, destroy it */
737 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
738 {
739 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
740 
741 #ifdef NET_REFCNT_DEBUG
742 	pr_debug("%s\n", __func__);
743 #endif
744 
745 	in6_dev_put(ifp->idev);
746 
747 	if (del_timer(&ifp->dad_timer))
748 		pr_notice("Timer is still running, when freeing ifa=%p\n", ifp);
749 
750 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
751 		pr_warn("Freeing alive inet6 address %p\n", ifp);
752 		return;
753 	}
754 	ip6_rt_put(ifp->rt);
755 
756 	kfree_rcu(ifp, rcu);
757 }
758 
759 static void
760 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
761 {
762 	struct list_head *p;
763 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
764 
765 	/*
766 	 * Each device address list is sorted in order of scope -
767 	 * global before linklocal.
768 	 */
769 	list_for_each(p, &idev->addr_list) {
770 		struct inet6_ifaddr *ifa
771 			= list_entry(p, struct inet6_ifaddr, if_list);
772 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
773 			break;
774 	}
775 
776 	list_add_tail(&ifp->if_list, p);
777 }
778 
779 static u32 inet6_addr_hash(const struct in6_addr *addr)
780 {
781 	return hash_32(ipv6_addr_hash(addr), IN6_ADDR_HSIZE_SHIFT);
782 }
783 
784 /* On success it returns ifp with increased reference count */
785 
786 static struct inet6_ifaddr *
787 ipv6_add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
788 	      const struct in6_addr *peer_addr, int pfxlen,
789 	      int scope, u32 flags, u32 valid_lft, u32 prefered_lft)
790 {
791 	struct inet6_ifaddr *ifa = NULL;
792 	struct rt6_info *rt;
793 	unsigned int hash;
794 	int err = 0;
795 	int addr_type = ipv6_addr_type(addr);
796 
797 	if (addr_type == IPV6_ADDR_ANY ||
798 	    addr_type & IPV6_ADDR_MULTICAST ||
799 	    (!(idev->dev->flags & IFF_LOOPBACK) &&
800 	     addr_type & IPV6_ADDR_LOOPBACK))
801 		return ERR_PTR(-EADDRNOTAVAIL);
802 
803 	rcu_read_lock_bh();
804 	if (idev->dead) {
805 		err = -ENODEV;			/*XXX*/
806 		goto out2;
807 	}
808 
809 	if (idev->cnf.disable_ipv6) {
810 		err = -EACCES;
811 		goto out2;
812 	}
813 
814 	spin_lock(&addrconf_hash_lock);
815 
816 	/* Ignore adding duplicate addresses on an interface */
817 	if (ipv6_chk_same_addr(dev_net(idev->dev), addr, idev->dev)) {
818 		ADBG("ipv6_add_addr: already assigned\n");
819 		err = -EEXIST;
820 		goto out;
821 	}
822 
823 	ifa = kzalloc(sizeof(struct inet6_ifaddr), GFP_ATOMIC);
824 
825 	if (ifa == NULL) {
826 		ADBG("ipv6_add_addr: malloc failed\n");
827 		err = -ENOBUFS;
828 		goto out;
829 	}
830 
831 	rt = addrconf_dst_alloc(idev, addr, false);
832 	if (IS_ERR(rt)) {
833 		err = PTR_ERR(rt);
834 		goto out;
835 	}
836 
837 	ifa->addr = *addr;
838 	if (peer_addr)
839 		ifa->peer_addr = *peer_addr;
840 
841 	spin_lock_init(&ifa->lock);
842 	spin_lock_init(&ifa->state_lock);
843 	setup_timer(&ifa->dad_timer, addrconf_dad_timer,
844 		    (unsigned long)ifa);
845 	INIT_HLIST_NODE(&ifa->addr_lst);
846 	ifa->scope = scope;
847 	ifa->prefix_len = pfxlen;
848 	ifa->flags = flags | IFA_F_TENTATIVE;
849 	ifa->valid_lft = valid_lft;
850 	ifa->prefered_lft = prefered_lft;
851 	ifa->cstamp = ifa->tstamp = jiffies;
852 	ifa->tokenized = false;
853 
854 	ifa->rt = rt;
855 
856 	ifa->idev = idev;
857 	in6_dev_hold(idev);
858 	/* For caller */
859 	in6_ifa_hold(ifa);
860 
861 	/* Add to big hash table */
862 	hash = inet6_addr_hash(addr);
863 
864 	hlist_add_head_rcu(&ifa->addr_lst, &inet6_addr_lst[hash]);
865 	spin_unlock(&addrconf_hash_lock);
866 
867 	write_lock(&idev->lock);
868 	/* Add to inet6_dev unicast addr list. */
869 	ipv6_link_dev_addr(idev, ifa);
870 
871 	if (ifa->flags&IFA_F_TEMPORARY) {
872 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
873 		in6_ifa_hold(ifa);
874 	}
875 
876 	in6_ifa_hold(ifa);
877 	write_unlock(&idev->lock);
878 out2:
879 	rcu_read_unlock_bh();
880 
881 	if (likely(err == 0))
882 		inet6addr_notifier_call_chain(NETDEV_UP, ifa);
883 	else {
884 		kfree(ifa);
885 		ifa = ERR_PTR(err);
886 	}
887 
888 	return ifa;
889 out:
890 	spin_unlock(&addrconf_hash_lock);
891 	goto out2;
892 }
893 
894 /* This function wants to get referenced ifp and releases it before return */
895 
896 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
897 {
898 	struct inet6_ifaddr *ifa, *ifn;
899 	struct inet6_dev *idev = ifp->idev;
900 	int state;
901 	int deleted = 0, onlink = 0;
902 	unsigned long expires = jiffies;
903 
904 	spin_lock_bh(&ifp->state_lock);
905 	state = ifp->state;
906 	ifp->state = INET6_IFADDR_STATE_DEAD;
907 	spin_unlock_bh(&ifp->state_lock);
908 
909 	if (state == INET6_IFADDR_STATE_DEAD)
910 		goto out;
911 
912 	spin_lock_bh(&addrconf_hash_lock);
913 	hlist_del_init_rcu(&ifp->addr_lst);
914 	spin_unlock_bh(&addrconf_hash_lock);
915 
916 	write_lock_bh(&idev->lock);
917 
918 	if (ifp->flags&IFA_F_TEMPORARY) {
919 		list_del(&ifp->tmp_list);
920 		if (ifp->ifpub) {
921 			in6_ifa_put(ifp->ifpub);
922 			ifp->ifpub = NULL;
923 		}
924 		__in6_ifa_put(ifp);
925 	}
926 
927 	list_for_each_entry_safe(ifa, ifn, &idev->addr_list, if_list) {
928 		if (ifa == ifp) {
929 			list_del_init(&ifp->if_list);
930 			__in6_ifa_put(ifp);
931 
932 			if (!(ifp->flags & IFA_F_PERMANENT) || onlink > 0)
933 				break;
934 			deleted = 1;
935 			continue;
936 		} else if (ifp->flags & IFA_F_PERMANENT) {
937 			if (ipv6_prefix_equal(&ifa->addr, &ifp->addr,
938 					      ifp->prefix_len)) {
939 				if (ifa->flags & IFA_F_PERMANENT) {
940 					onlink = 1;
941 					if (deleted)
942 						break;
943 				} else {
944 					unsigned long lifetime;
945 
946 					if (!onlink)
947 						onlink = -1;
948 
949 					spin_lock(&ifa->lock);
950 
951 					lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
952 					/*
953 					 * Note: Because this address is
954 					 * not permanent, lifetime <
955 					 * LONG_MAX / HZ here.
956 					 */
957 					if (time_before(expires,
958 							ifa->tstamp + lifetime * HZ))
959 						expires = ifa->tstamp + lifetime * HZ;
960 					spin_unlock(&ifa->lock);
961 				}
962 			}
963 		}
964 	}
965 	write_unlock_bh(&idev->lock);
966 
967 	addrconf_del_dad_timer(ifp);
968 
969 	ipv6_ifa_notify(RTM_DELADDR, ifp);
970 
971 	inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);
972 
973 	/*
974 	 * Purge or update corresponding prefix
975 	 *
976 	 * 1) we don't purge prefix here if address was not permanent.
977 	 *    prefix is managed by its own lifetime.
978 	 * 2) if there're no addresses, delete prefix.
979 	 * 3) if there're still other permanent address(es),
980 	 *    corresponding prefix is still permanent.
981 	 * 4) otherwise, update prefix lifetime to the
982 	 *    longest valid lifetime among the corresponding
983 	 *    addresses on the device.
984 	 *    Note: subsequent RA will update lifetime.
985 	 *
986 	 * --yoshfuji
987 	 */
988 	if ((ifp->flags & IFA_F_PERMANENT) && onlink < 1) {
989 		struct in6_addr prefix;
990 		struct rt6_info *rt;
991 
992 		ipv6_addr_prefix(&prefix, &ifp->addr, ifp->prefix_len);
993 
994 		rt = addrconf_get_prefix_route(&prefix,
995 					       ifp->prefix_len,
996 					       ifp->idev->dev,
997 					       0, RTF_GATEWAY | RTF_DEFAULT);
998 
999 		if (rt) {
1000 			if (onlink == 0) {
1001 				ip6_del_rt(rt);
1002 				rt = NULL;
1003 			} else if (!(rt->rt6i_flags & RTF_EXPIRES)) {
1004 				rt6_set_expires(rt, expires);
1005 			}
1006 		}
1007 		ip6_rt_put(rt);
1008 	}
1009 
1010 	/* clean up prefsrc entries */
1011 	rt6_remove_prefsrc(ifp);
1012 out:
1013 	in6_ifa_put(ifp);
1014 }
1015 
1016 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp, struct inet6_ifaddr *ift)
1017 {
1018 	struct inet6_dev *idev = ifp->idev;
1019 	struct in6_addr addr, *tmpaddr;
1020 	unsigned long tmp_prefered_lft, tmp_valid_lft, tmp_tstamp, age;
1021 	unsigned long regen_advance;
1022 	int tmp_plen;
1023 	int ret = 0;
1024 	u32 addr_flags;
1025 	unsigned long now = jiffies;
1026 
1027 	write_lock(&idev->lock);
1028 	if (ift) {
1029 		spin_lock_bh(&ift->lock);
1030 		memcpy(&addr.s6_addr[8], &ift->addr.s6_addr[8], 8);
1031 		spin_unlock_bh(&ift->lock);
1032 		tmpaddr = &addr;
1033 	} else {
1034 		tmpaddr = NULL;
1035 	}
1036 retry:
1037 	in6_dev_hold(idev);
1038 	if (idev->cnf.use_tempaddr <= 0) {
1039 		write_unlock(&idev->lock);
1040 		pr_info("%s: use_tempaddr is disabled\n", __func__);
1041 		in6_dev_put(idev);
1042 		ret = -1;
1043 		goto out;
1044 	}
1045 	spin_lock_bh(&ifp->lock);
1046 	if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
1047 		idev->cnf.use_tempaddr = -1;	/*XXX*/
1048 		spin_unlock_bh(&ifp->lock);
1049 		write_unlock(&idev->lock);
1050 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1051 			__func__);
1052 		in6_dev_put(idev);
1053 		ret = -1;
1054 		goto out;
1055 	}
1056 	in6_ifa_hold(ifp);
1057 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1058 	__ipv6_try_regen_rndid(idev, tmpaddr);
1059 	memcpy(&addr.s6_addr[8], idev->rndid, 8);
1060 	age = (now - ifp->tstamp) / HZ;
1061 	tmp_valid_lft = min_t(__u32,
1062 			      ifp->valid_lft,
1063 			      idev->cnf.temp_valid_lft + age);
1064 	tmp_prefered_lft = min_t(__u32,
1065 				 ifp->prefered_lft,
1066 				 idev->cnf.temp_prefered_lft + age -
1067 				 idev->cnf.max_desync_factor);
1068 	tmp_plen = ifp->prefix_len;
1069 	tmp_tstamp = ifp->tstamp;
1070 	spin_unlock_bh(&ifp->lock);
1071 
1072 	regen_advance = idev->cnf.regen_max_retry *
1073 	                idev->cnf.dad_transmits *
1074 	                idev->nd_parms->retrans_time / HZ;
1075 	write_unlock(&idev->lock);
1076 
1077 	/* A temporary address is created only if this calculated Preferred
1078 	 * Lifetime is greater than REGEN_ADVANCE time units.  In particular,
1079 	 * an implementation must not create a temporary address with a zero
1080 	 * Preferred Lifetime.
1081 	 */
1082 	if (tmp_prefered_lft <= regen_advance) {
1083 		in6_ifa_put(ifp);
1084 		in6_dev_put(idev);
1085 		ret = -1;
1086 		goto out;
1087 	}
1088 
1089 	addr_flags = IFA_F_TEMPORARY;
1090 	/* set in addrconf_prefix_rcv() */
1091 	if (ifp->flags & IFA_F_OPTIMISTIC)
1092 		addr_flags |= IFA_F_OPTIMISTIC;
1093 
1094 	ift = ipv6_add_addr(idev, &addr, NULL, tmp_plen,
1095 			    ipv6_addr_scope(&addr), addr_flags,
1096 			    tmp_valid_lft, tmp_prefered_lft);
1097 	if (IS_ERR(ift)) {
1098 		in6_ifa_put(ifp);
1099 		in6_dev_put(idev);
1100 		pr_info("%s: retry temporary address regeneration\n", __func__);
1101 		tmpaddr = &addr;
1102 		write_lock(&idev->lock);
1103 		goto retry;
1104 	}
1105 
1106 	spin_lock_bh(&ift->lock);
1107 	ift->ifpub = ifp;
1108 	ift->cstamp = now;
1109 	ift->tstamp = tmp_tstamp;
1110 	spin_unlock_bh(&ift->lock);
1111 
1112 	addrconf_dad_start(ift);
1113 	in6_ifa_put(ift);
1114 	in6_dev_put(idev);
1115 out:
1116 	return ret;
1117 }
1118 
1119 /*
1120  *	Choose an appropriate source address (RFC3484)
1121  */
1122 enum {
1123 	IPV6_SADDR_RULE_INIT = 0,
1124 	IPV6_SADDR_RULE_LOCAL,
1125 	IPV6_SADDR_RULE_SCOPE,
1126 	IPV6_SADDR_RULE_PREFERRED,
1127 #ifdef CONFIG_IPV6_MIP6
1128 	IPV6_SADDR_RULE_HOA,
1129 #endif
1130 	IPV6_SADDR_RULE_OIF,
1131 	IPV6_SADDR_RULE_LABEL,
1132 	IPV6_SADDR_RULE_PRIVACY,
1133 	IPV6_SADDR_RULE_ORCHID,
1134 	IPV6_SADDR_RULE_PREFIX,
1135 	IPV6_SADDR_RULE_MAX
1136 };
1137 
1138 struct ipv6_saddr_score {
1139 	int			rule;
1140 	int			addr_type;
1141 	struct inet6_ifaddr	*ifa;
1142 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1143 	int			scopedist;
1144 	int			matchlen;
1145 };
1146 
1147 struct ipv6_saddr_dst {
1148 	const struct in6_addr *addr;
1149 	int ifindex;
1150 	int scope;
1151 	int label;
1152 	unsigned int prefs;
1153 };
1154 
1155 static inline int ipv6_saddr_preferred(int type)
1156 {
1157 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1158 		return 1;
1159 	return 0;
1160 }
1161 
1162 static int ipv6_get_saddr_eval(struct net *net,
1163 			       struct ipv6_saddr_score *score,
1164 			       struct ipv6_saddr_dst *dst,
1165 			       int i)
1166 {
1167 	int ret;
1168 
1169 	if (i <= score->rule) {
1170 		switch (i) {
1171 		case IPV6_SADDR_RULE_SCOPE:
1172 			ret = score->scopedist;
1173 			break;
1174 		case IPV6_SADDR_RULE_PREFIX:
1175 			ret = score->matchlen;
1176 			break;
1177 		default:
1178 			ret = !!test_bit(i, score->scorebits);
1179 		}
1180 		goto out;
1181 	}
1182 
1183 	switch (i) {
1184 	case IPV6_SADDR_RULE_INIT:
1185 		/* Rule 0: remember if hiscore is not ready yet */
1186 		ret = !!score->ifa;
1187 		break;
1188 	case IPV6_SADDR_RULE_LOCAL:
1189 		/* Rule 1: Prefer same address */
1190 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1191 		break;
1192 	case IPV6_SADDR_RULE_SCOPE:
1193 		/* Rule 2: Prefer appropriate scope
1194 		 *
1195 		 *      ret
1196 		 *       ^
1197 		 *    -1 |  d 15
1198 		 *    ---+--+-+---> scope
1199 		 *       |
1200 		 *       |             d is scope of the destination.
1201 		 *  B-d  |  \
1202 		 *       |   \      <- smaller scope is better if
1203 		 *  B-15 |    \        if scope is enough for destinaion.
1204 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1205 		 * d-C-1 | /
1206 		 *       |/         <- greater is better
1207 		 *   -C  /             if scope is not enough for destination.
1208 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1209 		 *
1210 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1211 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1212 		 * Assume B = 0 and we get C > 29.
1213 		 */
1214 		ret = __ipv6_addr_src_scope(score->addr_type);
1215 		if (ret >= dst->scope)
1216 			ret = -ret;
1217 		else
1218 			ret -= 128;	/* 30 is enough */
1219 		score->scopedist = ret;
1220 		break;
1221 	case IPV6_SADDR_RULE_PREFERRED:
1222 		/* Rule 3: Avoid deprecated and optimistic addresses */
1223 		ret = ipv6_saddr_preferred(score->addr_type) ||
1224 		      !(score->ifa->flags & (IFA_F_DEPRECATED|IFA_F_OPTIMISTIC));
1225 		break;
1226 #ifdef CONFIG_IPV6_MIP6
1227 	case IPV6_SADDR_RULE_HOA:
1228 	    {
1229 		/* Rule 4: Prefer home address */
1230 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1231 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1232 		break;
1233 	    }
1234 #endif
1235 	case IPV6_SADDR_RULE_OIF:
1236 		/* Rule 5: Prefer outgoing interface */
1237 		ret = (!dst->ifindex ||
1238 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1239 		break;
1240 	case IPV6_SADDR_RULE_LABEL:
1241 		/* Rule 6: Prefer matching label */
1242 		ret = ipv6_addr_label(net,
1243 				      &score->ifa->addr, score->addr_type,
1244 				      score->ifa->idev->dev->ifindex) == dst->label;
1245 		break;
1246 	case IPV6_SADDR_RULE_PRIVACY:
1247 	    {
1248 		/* Rule 7: Prefer public address
1249 		 * Note: prefer temporary address if use_tempaddr >= 2
1250 		 */
1251 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1252 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1253 				score->ifa->idev->cnf.use_tempaddr >= 2;
1254 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1255 		break;
1256 	    }
1257 	case IPV6_SADDR_RULE_ORCHID:
1258 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1259 		 *	    non-ORCHID vs non-ORCHID
1260 		 */
1261 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1262 			ipv6_addr_orchid(dst->addr));
1263 		break;
1264 	case IPV6_SADDR_RULE_PREFIX:
1265 		/* Rule 8: Use longest matching prefix */
1266 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1267 		if (ret > score->ifa->prefix_len)
1268 			ret = score->ifa->prefix_len;
1269 		score->matchlen = ret;
1270 		break;
1271 	default:
1272 		ret = 0;
1273 	}
1274 
1275 	if (ret)
1276 		__set_bit(i, score->scorebits);
1277 	score->rule = i;
1278 out:
1279 	return ret;
1280 }
1281 
1282 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1283 		       const struct in6_addr *daddr, unsigned int prefs,
1284 		       struct in6_addr *saddr)
1285 {
1286 	struct ipv6_saddr_score scores[2],
1287 				*score = &scores[0], *hiscore = &scores[1];
1288 	struct ipv6_saddr_dst dst;
1289 	struct net_device *dev;
1290 	int dst_type;
1291 
1292 	dst_type = __ipv6_addr_type(daddr);
1293 	dst.addr = daddr;
1294 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1295 	dst.scope = __ipv6_addr_src_scope(dst_type);
1296 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1297 	dst.prefs = prefs;
1298 
1299 	hiscore->rule = -1;
1300 	hiscore->ifa = NULL;
1301 
1302 	rcu_read_lock();
1303 
1304 	for_each_netdev_rcu(net, dev) {
1305 		struct inet6_dev *idev;
1306 
1307 		/* Candidate Source Address (section 4)
1308 		 *  - multicast and link-local destination address,
1309 		 *    the set of candidate source address MUST only
1310 		 *    include addresses assigned to interfaces
1311 		 *    belonging to the same link as the outgoing
1312 		 *    interface.
1313 		 * (- For site-local destination addresses, the
1314 		 *    set of candidate source addresses MUST only
1315 		 *    include addresses assigned to interfaces
1316 		 *    belonging to the same site as the outgoing
1317 		 *    interface.)
1318 		 */
1319 		if (((dst_type & IPV6_ADDR_MULTICAST) ||
1320 		     dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL) &&
1321 		    dst.ifindex && dev->ifindex != dst.ifindex)
1322 			continue;
1323 
1324 		idev = __in6_dev_get(dev);
1325 		if (!idev)
1326 			continue;
1327 
1328 		read_lock_bh(&idev->lock);
1329 		list_for_each_entry(score->ifa, &idev->addr_list, if_list) {
1330 			int i;
1331 
1332 			/*
1333 			 * - Tentative Address (RFC2462 section 5.4)
1334 			 *  - A tentative address is not considered
1335 			 *    "assigned to an interface" in the traditional
1336 			 *    sense, unless it is also flagged as optimistic.
1337 			 * - Candidate Source Address (section 4)
1338 			 *  - In any case, anycast addresses, multicast
1339 			 *    addresses, and the unspecified address MUST
1340 			 *    NOT be included in a candidate set.
1341 			 */
1342 			if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1343 			    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1344 				continue;
1345 
1346 			score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1347 
1348 			if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1349 				     score->addr_type & IPV6_ADDR_MULTICAST)) {
1350 				LIMIT_NETDEBUG(KERN_DEBUG
1351 					       "ADDRCONF: unspecified / multicast address "
1352 					       "assigned as unicast address on %s",
1353 					       dev->name);
1354 				continue;
1355 			}
1356 
1357 			score->rule = -1;
1358 			bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1359 
1360 			for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1361 				int minihiscore, miniscore;
1362 
1363 				minihiscore = ipv6_get_saddr_eval(net, hiscore, &dst, i);
1364 				miniscore = ipv6_get_saddr_eval(net, score, &dst, i);
1365 
1366 				if (minihiscore > miniscore) {
1367 					if (i == IPV6_SADDR_RULE_SCOPE &&
1368 					    score->scopedist > 0) {
1369 						/*
1370 						 * special case:
1371 						 * each remaining entry
1372 						 * has too small (not enough)
1373 						 * scope, because ifa entries
1374 						 * are sorted by their scope
1375 						 * values.
1376 						 */
1377 						goto try_nextdev;
1378 					}
1379 					break;
1380 				} else if (minihiscore < miniscore) {
1381 					if (hiscore->ifa)
1382 						in6_ifa_put(hiscore->ifa);
1383 
1384 					in6_ifa_hold(score->ifa);
1385 
1386 					swap(hiscore, score);
1387 
1388 					/* restore our iterator */
1389 					score->ifa = hiscore->ifa;
1390 
1391 					break;
1392 				}
1393 			}
1394 		}
1395 try_nextdev:
1396 		read_unlock_bh(&idev->lock);
1397 	}
1398 	rcu_read_unlock();
1399 
1400 	if (!hiscore->ifa)
1401 		return -EADDRNOTAVAIL;
1402 
1403 	*saddr = hiscore->ifa->addr;
1404 	in6_ifa_put(hiscore->ifa);
1405 	return 0;
1406 }
1407 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1408 
1409 int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr,
1410 		      unsigned char banned_flags)
1411 {
1412 	struct inet6_ifaddr *ifp;
1413 	int err = -EADDRNOTAVAIL;
1414 
1415 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
1416 		if (ifp->scope == IFA_LINK &&
1417 		    !(ifp->flags & banned_flags)) {
1418 			*addr = ifp->addr;
1419 			err = 0;
1420 			break;
1421 		}
1422 	}
1423 	return err;
1424 }
1425 
1426 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1427 		    unsigned char banned_flags)
1428 {
1429 	struct inet6_dev *idev;
1430 	int err = -EADDRNOTAVAIL;
1431 
1432 	rcu_read_lock();
1433 	idev = __in6_dev_get(dev);
1434 	if (idev) {
1435 		read_lock_bh(&idev->lock);
1436 		err = __ipv6_get_lladdr(idev, addr, banned_flags);
1437 		read_unlock_bh(&idev->lock);
1438 	}
1439 	rcu_read_unlock();
1440 	return err;
1441 }
1442 
1443 static int ipv6_count_addresses(struct inet6_dev *idev)
1444 {
1445 	int cnt = 0;
1446 	struct inet6_ifaddr *ifp;
1447 
1448 	read_lock_bh(&idev->lock);
1449 	list_for_each_entry(ifp, &idev->addr_list, if_list)
1450 		cnt++;
1451 	read_unlock_bh(&idev->lock);
1452 	return cnt;
1453 }
1454 
1455 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1456 		  const struct net_device *dev, int strict)
1457 {
1458 	struct inet6_ifaddr *ifp;
1459 	unsigned int hash = inet6_addr_hash(addr);
1460 
1461 	rcu_read_lock_bh();
1462 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
1463 		if (!net_eq(dev_net(ifp->idev->dev), net))
1464 			continue;
1465 		if (ipv6_addr_equal(&ifp->addr, addr) &&
1466 		    !(ifp->flags&IFA_F_TENTATIVE) &&
1467 		    (dev == NULL || ifp->idev->dev == dev ||
1468 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1469 			rcu_read_unlock_bh();
1470 			return 1;
1471 		}
1472 	}
1473 
1474 	rcu_read_unlock_bh();
1475 	return 0;
1476 }
1477 EXPORT_SYMBOL(ipv6_chk_addr);
1478 
1479 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
1480 			       struct net_device *dev)
1481 {
1482 	unsigned int hash = inet6_addr_hash(addr);
1483 	struct inet6_ifaddr *ifp;
1484 
1485 	hlist_for_each_entry(ifp, &inet6_addr_lst[hash], addr_lst) {
1486 		if (!net_eq(dev_net(ifp->idev->dev), net))
1487 			continue;
1488 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1489 			if (dev == NULL || ifp->idev->dev == dev)
1490 				return true;
1491 		}
1492 	}
1493 	return false;
1494 }
1495 
1496 /* Compares an address/prefix_len with addresses on device @dev.
1497  * If one is found it returns true.
1498  */
1499 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
1500 	const unsigned int prefix_len, struct net_device *dev)
1501 {
1502 	struct inet6_dev *idev;
1503 	struct inet6_ifaddr *ifa;
1504 	bool ret = false;
1505 
1506 	rcu_read_lock();
1507 	idev = __in6_dev_get(dev);
1508 	if (idev) {
1509 		read_lock_bh(&idev->lock);
1510 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
1511 			ret = ipv6_prefix_equal(addr, &ifa->addr, prefix_len);
1512 			if (ret)
1513 				break;
1514 		}
1515 		read_unlock_bh(&idev->lock);
1516 	}
1517 	rcu_read_unlock();
1518 
1519 	return ret;
1520 }
1521 EXPORT_SYMBOL(ipv6_chk_custom_prefix);
1522 
1523 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
1524 {
1525 	struct inet6_dev *idev;
1526 	struct inet6_ifaddr *ifa;
1527 	int	onlink;
1528 
1529 	onlink = 0;
1530 	rcu_read_lock();
1531 	idev = __in6_dev_get(dev);
1532 	if (idev) {
1533 		read_lock_bh(&idev->lock);
1534 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
1535 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
1536 						   ifa->prefix_len);
1537 			if (onlink)
1538 				break;
1539 		}
1540 		read_unlock_bh(&idev->lock);
1541 	}
1542 	rcu_read_unlock();
1543 	return onlink;
1544 }
1545 EXPORT_SYMBOL(ipv6_chk_prefix);
1546 
1547 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
1548 				     struct net_device *dev, int strict)
1549 {
1550 	struct inet6_ifaddr *ifp, *result = NULL;
1551 	unsigned int hash = inet6_addr_hash(addr);
1552 
1553 	rcu_read_lock_bh();
1554 	hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[hash], addr_lst) {
1555 		if (!net_eq(dev_net(ifp->idev->dev), net))
1556 			continue;
1557 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1558 			if (dev == NULL || ifp->idev->dev == dev ||
1559 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
1560 				result = ifp;
1561 				in6_ifa_hold(ifp);
1562 				break;
1563 			}
1564 		}
1565 	}
1566 	rcu_read_unlock_bh();
1567 
1568 	return result;
1569 }
1570 
1571 /* Gets referenced address, destroys ifaddr */
1572 
1573 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
1574 {
1575 	if (ifp->flags&IFA_F_PERMANENT) {
1576 		spin_lock_bh(&ifp->lock);
1577 		addrconf_del_dad_timer(ifp);
1578 		ifp->flags |= IFA_F_TENTATIVE;
1579 		if (dad_failed)
1580 			ifp->flags |= IFA_F_DADFAILED;
1581 		spin_unlock_bh(&ifp->lock);
1582 		if (dad_failed)
1583 			ipv6_ifa_notify(0, ifp);
1584 		in6_ifa_put(ifp);
1585 	} else if (ifp->flags&IFA_F_TEMPORARY) {
1586 		struct inet6_ifaddr *ifpub;
1587 		spin_lock_bh(&ifp->lock);
1588 		ifpub = ifp->ifpub;
1589 		if (ifpub) {
1590 			in6_ifa_hold(ifpub);
1591 			spin_unlock_bh(&ifp->lock);
1592 			ipv6_create_tempaddr(ifpub, ifp);
1593 			in6_ifa_put(ifpub);
1594 		} else {
1595 			spin_unlock_bh(&ifp->lock);
1596 		}
1597 		ipv6_del_addr(ifp);
1598 	} else
1599 		ipv6_del_addr(ifp);
1600 }
1601 
1602 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
1603 {
1604 	int err = -ENOENT;
1605 
1606 	spin_lock(&ifp->state_lock);
1607 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
1608 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
1609 		err = 0;
1610 	}
1611 	spin_unlock(&ifp->state_lock);
1612 
1613 	return err;
1614 }
1615 
1616 void addrconf_dad_failure(struct inet6_ifaddr *ifp)
1617 {
1618 	struct inet6_dev *idev = ifp->idev;
1619 
1620 	if (addrconf_dad_end(ifp)) {
1621 		in6_ifa_put(ifp);
1622 		return;
1623 	}
1624 
1625 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c detected!\n",
1626 			     ifp->idev->dev->name, &ifp->addr);
1627 
1628 	if (idev->cnf.accept_dad > 1 && !idev->cnf.disable_ipv6) {
1629 		struct in6_addr addr;
1630 
1631 		addr.s6_addr32[0] = htonl(0xfe800000);
1632 		addr.s6_addr32[1] = 0;
1633 
1634 		if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
1635 		    ipv6_addr_equal(&ifp->addr, &addr)) {
1636 			/* DAD failed for link-local based on MAC address */
1637 			idev->cnf.disable_ipv6 = 1;
1638 
1639 			pr_info("%s: IPv6 being disabled!\n",
1640 				ifp->idev->dev->name);
1641 		}
1642 	}
1643 
1644 	addrconf_dad_stop(ifp, 1);
1645 }
1646 
1647 /* Join to solicited addr multicast group. */
1648 
1649 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
1650 {
1651 	struct in6_addr maddr;
1652 
1653 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
1654 		return;
1655 
1656 	addrconf_addr_solict_mult(addr, &maddr);
1657 	ipv6_dev_mc_inc(dev, &maddr);
1658 }
1659 
1660 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
1661 {
1662 	struct in6_addr maddr;
1663 
1664 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
1665 		return;
1666 
1667 	addrconf_addr_solict_mult(addr, &maddr);
1668 	__ipv6_dev_mc_dec(idev, &maddr);
1669 }
1670 
1671 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
1672 {
1673 	struct in6_addr addr;
1674 	if (ifp->prefix_len >= 127) /* RFC 6164 */
1675 		return;
1676 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
1677 	if (ipv6_addr_any(&addr))
1678 		return;
1679 	ipv6_dev_ac_inc(ifp->idev->dev, &addr);
1680 }
1681 
1682 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
1683 {
1684 	struct in6_addr addr;
1685 	if (ifp->prefix_len >= 127) /* RFC 6164 */
1686 		return;
1687 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
1688 	if (ipv6_addr_any(&addr))
1689 		return;
1690 	__ipv6_dev_ac_dec(ifp->idev, &addr);
1691 }
1692 
1693 static int addrconf_ifid_eui48(u8 *eui, struct net_device *dev)
1694 {
1695 	if (dev->addr_len != ETH_ALEN)
1696 		return -1;
1697 	memcpy(eui, dev->dev_addr, 3);
1698 	memcpy(eui + 5, dev->dev_addr + 3, 3);
1699 
1700 	/*
1701 	 * The zSeries OSA network cards can be shared among various
1702 	 * OS instances, but the OSA cards have only one MAC address.
1703 	 * This leads to duplicate address conflicts in conjunction
1704 	 * with IPv6 if more than one instance uses the same card.
1705 	 *
1706 	 * The driver for these cards can deliver a unique 16-bit
1707 	 * identifier for each instance sharing the same card.  It is
1708 	 * placed instead of 0xFFFE in the interface identifier.  The
1709 	 * "u" bit of the interface identifier is not inverted in this
1710 	 * case.  Hence the resulting interface identifier has local
1711 	 * scope according to RFC2373.
1712 	 */
1713 	if (dev->dev_id) {
1714 		eui[3] = (dev->dev_id >> 8) & 0xFF;
1715 		eui[4] = dev->dev_id & 0xFF;
1716 	} else {
1717 		eui[3] = 0xFF;
1718 		eui[4] = 0xFE;
1719 		eui[0] ^= 2;
1720 	}
1721 	return 0;
1722 }
1723 
1724 static int addrconf_ifid_eui64(u8 *eui, struct net_device *dev)
1725 {
1726 	if (dev->addr_len != IEEE802154_ADDR_LEN)
1727 		return -1;
1728 	memcpy(eui, dev->dev_addr, 8);
1729 	eui[0] ^= 2;
1730 	return 0;
1731 }
1732 
1733 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
1734 {
1735 	union fwnet_hwaddr *ha;
1736 
1737 	if (dev->addr_len != FWNET_ALEN)
1738 		return -1;
1739 
1740 	ha = (union fwnet_hwaddr *)dev->dev_addr;
1741 
1742 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
1743 	eui[0] ^= 2;
1744 	return 0;
1745 }
1746 
1747 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
1748 {
1749 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
1750 	if (dev->addr_len != ARCNET_ALEN)
1751 		return -1;
1752 	memset(eui, 0, 7);
1753 	eui[7] = *(u8 *)dev->dev_addr;
1754 	return 0;
1755 }
1756 
1757 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
1758 {
1759 	if (dev->addr_len != INFINIBAND_ALEN)
1760 		return -1;
1761 	memcpy(eui, dev->dev_addr + 12, 8);
1762 	eui[0] |= 2;
1763 	return 0;
1764 }
1765 
1766 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
1767 {
1768 	if (addr == 0)
1769 		return -1;
1770 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
1771 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
1772 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
1773 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
1774 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
1775 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
1776 	eui[1] = 0;
1777 	eui[2] = 0x5E;
1778 	eui[3] = 0xFE;
1779 	memcpy(eui + 4, &addr, 4);
1780 	return 0;
1781 }
1782 
1783 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
1784 {
1785 	if (dev->priv_flags & IFF_ISATAP)
1786 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
1787 	return -1;
1788 }
1789 
1790 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
1791 {
1792 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
1793 }
1794 
1795 static int addrconf_ifid_ip6tnl(u8 *eui, struct net_device *dev)
1796 {
1797 	memcpy(eui, dev->perm_addr, 3);
1798 	memcpy(eui + 5, dev->perm_addr + 3, 3);
1799 	eui[3] = 0xFF;
1800 	eui[4] = 0xFE;
1801 	eui[0] ^= 2;
1802 	return 0;
1803 }
1804 
1805 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
1806 {
1807 	switch (dev->type) {
1808 	case ARPHRD_ETHER:
1809 	case ARPHRD_FDDI:
1810 		return addrconf_ifid_eui48(eui, dev);
1811 	case ARPHRD_ARCNET:
1812 		return addrconf_ifid_arcnet(eui, dev);
1813 	case ARPHRD_INFINIBAND:
1814 		return addrconf_ifid_infiniband(eui, dev);
1815 	case ARPHRD_SIT:
1816 		return addrconf_ifid_sit(eui, dev);
1817 	case ARPHRD_IPGRE:
1818 		return addrconf_ifid_gre(eui, dev);
1819 	case ARPHRD_IEEE802154:
1820 		return addrconf_ifid_eui64(eui, dev);
1821 	case ARPHRD_IEEE1394:
1822 		return addrconf_ifid_ieee1394(eui, dev);
1823 	case ARPHRD_TUNNEL6:
1824 		return addrconf_ifid_ip6tnl(eui, dev);
1825 	}
1826 	return -1;
1827 }
1828 
1829 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
1830 {
1831 	int err = -1;
1832 	struct inet6_ifaddr *ifp;
1833 
1834 	read_lock_bh(&idev->lock);
1835 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
1836 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
1837 			memcpy(eui, ifp->addr.s6_addr+8, 8);
1838 			err = 0;
1839 			break;
1840 		}
1841 	}
1842 	read_unlock_bh(&idev->lock);
1843 	return err;
1844 }
1845 
1846 /* (re)generation of randomized interface identifier (RFC 3041 3.2, 3.5) */
1847 static void __ipv6_regen_rndid(struct inet6_dev *idev)
1848 {
1849 regen:
1850 	get_random_bytes(idev->rndid, sizeof(idev->rndid));
1851 	idev->rndid[0] &= ~0x02;
1852 
1853 	/*
1854 	 * <draft-ietf-ipngwg-temp-addresses-v2-00.txt>:
1855 	 * check if generated address is not inappropriate
1856 	 *
1857 	 *  - Reserved subnet anycast (RFC 2526)
1858 	 *	11111101 11....11 1xxxxxxx
1859 	 *  - ISATAP (RFC4214) 6.1
1860 	 *	00-00-5E-FE-xx-xx-xx-xx
1861 	 *  - value 0
1862 	 *  - XXX: already assigned to an address on the device
1863 	 */
1864 	if (idev->rndid[0] == 0xfd &&
1865 	    (idev->rndid[1]&idev->rndid[2]&idev->rndid[3]&idev->rndid[4]&idev->rndid[5]&idev->rndid[6]) == 0xff &&
1866 	    (idev->rndid[7]&0x80))
1867 		goto regen;
1868 	if ((idev->rndid[0]|idev->rndid[1]) == 0) {
1869 		if (idev->rndid[2] == 0x5e && idev->rndid[3] == 0xfe)
1870 			goto regen;
1871 		if ((idev->rndid[2]|idev->rndid[3]|idev->rndid[4]|idev->rndid[5]|idev->rndid[6]|idev->rndid[7]) == 0x00)
1872 			goto regen;
1873 	}
1874 }
1875 
1876 static void ipv6_regen_rndid(unsigned long data)
1877 {
1878 	struct inet6_dev *idev = (struct inet6_dev *) data;
1879 	unsigned long expires;
1880 
1881 	rcu_read_lock_bh();
1882 	write_lock_bh(&idev->lock);
1883 
1884 	if (idev->dead)
1885 		goto out;
1886 
1887 	__ipv6_regen_rndid(idev);
1888 
1889 	expires = jiffies +
1890 		idev->cnf.temp_prefered_lft * HZ -
1891 		idev->cnf.regen_max_retry * idev->cnf.dad_transmits * idev->nd_parms->retrans_time -
1892 		idev->cnf.max_desync_factor * HZ;
1893 	if (time_before(expires, jiffies)) {
1894 		pr_warn("%s: too short regeneration interval; timer disabled for %s\n",
1895 			__func__, idev->dev->name);
1896 		goto out;
1897 	}
1898 
1899 	if (!mod_timer(&idev->regen_timer, expires))
1900 		in6_dev_hold(idev);
1901 
1902 out:
1903 	write_unlock_bh(&idev->lock);
1904 	rcu_read_unlock_bh();
1905 	in6_dev_put(idev);
1906 }
1907 
1908 static void  __ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr)
1909 {
1910 	if (tmpaddr && memcmp(idev->rndid, &tmpaddr->s6_addr[8], 8) == 0)
1911 		__ipv6_regen_rndid(idev);
1912 }
1913 
1914 /*
1915  *	Add prefix route.
1916  */
1917 
1918 static void
1919 addrconf_prefix_route(struct in6_addr *pfx, int plen, struct net_device *dev,
1920 		      unsigned long expires, u32 flags)
1921 {
1922 	struct fib6_config cfg = {
1923 		.fc_table = RT6_TABLE_PREFIX,
1924 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
1925 		.fc_ifindex = dev->ifindex,
1926 		.fc_expires = expires,
1927 		.fc_dst_len = plen,
1928 		.fc_flags = RTF_UP | flags,
1929 		.fc_nlinfo.nl_net = dev_net(dev),
1930 		.fc_protocol = RTPROT_KERNEL,
1931 	};
1932 
1933 	cfg.fc_dst = *pfx;
1934 
1935 	/* Prevent useless cloning on PtP SIT.
1936 	   This thing is done here expecting that the whole
1937 	   class of non-broadcast devices need not cloning.
1938 	 */
1939 #if IS_ENABLED(CONFIG_IPV6_SIT)
1940 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
1941 		cfg.fc_flags |= RTF_NONEXTHOP;
1942 #endif
1943 
1944 	ip6_route_add(&cfg);
1945 }
1946 
1947 
1948 static struct rt6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
1949 						  int plen,
1950 						  const struct net_device *dev,
1951 						  u32 flags, u32 noflags)
1952 {
1953 	struct fib6_node *fn;
1954 	struct rt6_info *rt = NULL;
1955 	struct fib6_table *table;
1956 
1957 	table = fib6_get_table(dev_net(dev), RT6_TABLE_PREFIX);
1958 	if (table == NULL)
1959 		return NULL;
1960 
1961 	read_lock_bh(&table->tb6_lock);
1962 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0);
1963 	if (!fn)
1964 		goto out;
1965 	for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
1966 		if (rt->dst.dev->ifindex != dev->ifindex)
1967 			continue;
1968 		if ((rt->rt6i_flags & flags) != flags)
1969 			continue;
1970 		if ((rt->rt6i_flags & noflags) != 0)
1971 			continue;
1972 		dst_hold(&rt->dst);
1973 		break;
1974 	}
1975 out:
1976 	read_unlock_bh(&table->tb6_lock);
1977 	return rt;
1978 }
1979 
1980 
1981 /* Create "default" multicast route to the interface */
1982 
1983 static void addrconf_add_mroute(struct net_device *dev)
1984 {
1985 	struct fib6_config cfg = {
1986 		.fc_table = RT6_TABLE_LOCAL,
1987 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
1988 		.fc_ifindex = dev->ifindex,
1989 		.fc_dst_len = 8,
1990 		.fc_flags = RTF_UP,
1991 		.fc_nlinfo.nl_net = dev_net(dev),
1992 	};
1993 
1994 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
1995 
1996 	ip6_route_add(&cfg);
1997 }
1998 
1999 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2000 {
2001 	struct inet6_dev *idev;
2002 
2003 	ASSERT_RTNL();
2004 
2005 	idev = ipv6_find_idev(dev);
2006 	if (!idev)
2007 		return ERR_PTR(-ENOBUFS);
2008 
2009 	if (idev->cnf.disable_ipv6)
2010 		return ERR_PTR(-EACCES);
2011 
2012 	/* Add default multicast route */
2013 	if (!(dev->flags & IFF_LOOPBACK))
2014 		addrconf_add_mroute(dev);
2015 
2016 	return idev;
2017 }
2018 
2019 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2020 {
2021 	struct prefix_info *pinfo;
2022 	__u32 valid_lft;
2023 	__u32 prefered_lft;
2024 	int addr_type;
2025 	struct inet6_dev *in6_dev;
2026 	struct net *net = dev_net(dev);
2027 
2028 	pinfo = (struct prefix_info *) opt;
2029 
2030 	if (len < sizeof(struct prefix_info)) {
2031 		ADBG("addrconf: prefix option too short\n");
2032 		return;
2033 	}
2034 
2035 	/*
2036 	 *	Validation checks ([ADDRCONF], page 19)
2037 	 */
2038 
2039 	addr_type = ipv6_addr_type(&pinfo->prefix);
2040 
2041 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2042 		return;
2043 
2044 	valid_lft = ntohl(pinfo->valid);
2045 	prefered_lft = ntohl(pinfo->prefered);
2046 
2047 	if (prefered_lft > valid_lft) {
2048 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2049 		return;
2050 	}
2051 
2052 	in6_dev = in6_dev_get(dev);
2053 
2054 	if (in6_dev == NULL) {
2055 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2056 				    dev->name);
2057 		return;
2058 	}
2059 
2060 	/*
2061 	 *	Two things going on here:
2062 	 *	1) Add routes for on-link prefixes
2063 	 *	2) Configure prefixes with the auto flag set
2064 	 */
2065 
2066 	if (pinfo->onlink) {
2067 		struct rt6_info *rt;
2068 		unsigned long rt_expires;
2069 
2070 		/* Avoid arithmetic overflow. Really, we could
2071 		 * save rt_expires in seconds, likely valid_lft,
2072 		 * but it would require division in fib gc, that it
2073 		 * not good.
2074 		 */
2075 		if (HZ > USER_HZ)
2076 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2077 		else
2078 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2079 
2080 		if (addrconf_finite_timeout(rt_expires))
2081 			rt_expires *= HZ;
2082 
2083 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2084 					       pinfo->prefix_len,
2085 					       dev,
2086 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2087 					       RTF_GATEWAY | RTF_DEFAULT);
2088 
2089 		if (rt) {
2090 			/* Autoconf prefix route */
2091 			if (valid_lft == 0) {
2092 				ip6_del_rt(rt);
2093 				rt = NULL;
2094 			} else if (addrconf_finite_timeout(rt_expires)) {
2095 				/* not infinity */
2096 				rt6_set_expires(rt, jiffies + rt_expires);
2097 			} else {
2098 				rt6_clean_expires(rt);
2099 			}
2100 		} else if (valid_lft) {
2101 			clock_t expires = 0;
2102 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2103 			if (addrconf_finite_timeout(rt_expires)) {
2104 				/* not infinity */
2105 				flags |= RTF_EXPIRES;
2106 				expires = jiffies_to_clock_t(rt_expires);
2107 			}
2108 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2109 					      dev, expires, flags);
2110 		}
2111 		ip6_rt_put(rt);
2112 	}
2113 
2114 	/* Try to figure out our local address for this prefix */
2115 
2116 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
2117 		struct inet6_ifaddr *ifp;
2118 		struct in6_addr addr;
2119 		int create = 0, update_lft = 0;
2120 		bool tokenized = false;
2121 
2122 		if (pinfo->prefix_len == 64) {
2123 			memcpy(&addr, &pinfo->prefix, 8);
2124 
2125 			if (!ipv6_addr_any(&in6_dev->token)) {
2126 				read_lock_bh(&in6_dev->lock);
2127 				memcpy(addr.s6_addr + 8,
2128 				       in6_dev->token.s6_addr + 8, 8);
2129 				read_unlock_bh(&in6_dev->lock);
2130 				tokenized = true;
2131 			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2132 				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2133 				in6_dev_put(in6_dev);
2134 				return;
2135 			}
2136 			goto ok;
2137 		}
2138 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2139 				    pinfo->prefix_len);
2140 		in6_dev_put(in6_dev);
2141 		return;
2142 
2143 ok:
2144 
2145 		ifp = ipv6_get_ifaddr(net, &addr, dev, 1);
2146 
2147 		if (ifp == NULL && valid_lft) {
2148 			int max_addresses = in6_dev->cnf.max_addresses;
2149 			u32 addr_flags = 0;
2150 
2151 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2152 			if (in6_dev->cnf.optimistic_dad &&
2153 			    !net->ipv6.devconf_all->forwarding && sllao)
2154 				addr_flags = IFA_F_OPTIMISTIC;
2155 #endif
2156 
2157 			/* Do not allow to create too much of autoconfigured
2158 			 * addresses; this would be too easy way to crash kernel.
2159 			 */
2160 			if (!max_addresses ||
2161 			    ipv6_count_addresses(in6_dev) < max_addresses)
2162 				ifp = ipv6_add_addr(in6_dev, &addr, NULL,
2163 						    pinfo->prefix_len,
2164 						    addr_type&IPV6_ADDR_SCOPE_MASK,
2165 						    addr_flags, valid_lft,
2166 						    prefered_lft);
2167 
2168 			if (IS_ERR_OR_NULL(ifp)) {
2169 				in6_dev_put(in6_dev);
2170 				return;
2171 			}
2172 
2173 			update_lft = 0;
2174 			create = 1;
2175 			ifp->cstamp = jiffies;
2176 			ifp->tokenized = tokenized;
2177 			addrconf_dad_start(ifp);
2178 		}
2179 
2180 		if (ifp) {
2181 			int flags;
2182 			unsigned long now;
2183 			struct inet6_ifaddr *ift;
2184 			u32 stored_lft;
2185 
2186 			/* update lifetime (RFC2462 5.5.3 e) */
2187 			spin_lock(&ifp->lock);
2188 			now = jiffies;
2189 			if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2190 				stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2191 			else
2192 				stored_lft = 0;
2193 			if (!update_lft && !create && stored_lft) {
2194 				const u32 minimum_lft = min(
2195 					stored_lft, (u32)MIN_VALID_LIFETIME);
2196 				valid_lft = max(valid_lft, minimum_lft);
2197 
2198 				/* RFC4862 Section 5.5.3e:
2199 				 * "Note that the preferred lifetime of the
2200 				 *  corresponding address is always reset to
2201 				 *  the Preferred Lifetime in the received
2202 				 *  Prefix Information option, regardless of
2203 				 *  whether the valid lifetime is also reset or
2204 				 *  ignored."
2205 				 *
2206 				 * So we should always update prefered_lft here.
2207 				 */
2208 				update_lft = 1;
2209 			}
2210 
2211 			if (update_lft) {
2212 				ifp->valid_lft = valid_lft;
2213 				ifp->prefered_lft = prefered_lft;
2214 				ifp->tstamp = now;
2215 				flags = ifp->flags;
2216 				ifp->flags &= ~IFA_F_DEPRECATED;
2217 				spin_unlock(&ifp->lock);
2218 
2219 				if (!(flags&IFA_F_TENTATIVE))
2220 					ipv6_ifa_notify(0, ifp);
2221 			} else
2222 				spin_unlock(&ifp->lock);
2223 
2224 			read_lock_bh(&in6_dev->lock);
2225 			/* update all temporary addresses in the list */
2226 			list_for_each_entry(ift, &in6_dev->tempaddr_list,
2227 					    tmp_list) {
2228 				int age, max_valid, max_prefered;
2229 
2230 				if (ifp != ift->ifpub)
2231 					continue;
2232 
2233 				/*
2234 				 * RFC 4941 section 3.3:
2235 				 * If a received option will extend the lifetime
2236 				 * of a public address, the lifetimes of
2237 				 * temporary addresses should be extended,
2238 				 * subject to the overall constraint that no
2239 				 * temporary addresses should ever remain
2240 				 * "valid" or "preferred" for a time longer than
2241 				 * (TEMP_VALID_LIFETIME) or
2242 				 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR),
2243 				 * respectively.
2244 				 */
2245 				age = (now - ift->cstamp) / HZ;
2246 				max_valid = in6_dev->cnf.temp_valid_lft - age;
2247 				if (max_valid < 0)
2248 					max_valid = 0;
2249 
2250 				max_prefered = in6_dev->cnf.temp_prefered_lft -
2251 					       in6_dev->cnf.max_desync_factor -
2252 					       age;
2253 				if (max_prefered < 0)
2254 					max_prefered = 0;
2255 
2256 				if (valid_lft > max_valid)
2257 					valid_lft = max_valid;
2258 
2259 				if (prefered_lft > max_prefered)
2260 					prefered_lft = max_prefered;
2261 
2262 				spin_lock(&ift->lock);
2263 				flags = ift->flags;
2264 				ift->valid_lft = valid_lft;
2265 				ift->prefered_lft = prefered_lft;
2266 				ift->tstamp = now;
2267 				if (prefered_lft > 0)
2268 					ift->flags &= ~IFA_F_DEPRECATED;
2269 
2270 				spin_unlock(&ift->lock);
2271 				if (!(flags&IFA_F_TENTATIVE))
2272 					ipv6_ifa_notify(0, ift);
2273 			}
2274 
2275 			if ((create || list_empty(&in6_dev->tempaddr_list)) && in6_dev->cnf.use_tempaddr > 0) {
2276 				/*
2277 				 * When a new public address is created as
2278 				 * described in [ADDRCONF], also create a new
2279 				 * temporary address. Also create a temporary
2280 				 * address if it's enabled but no temporary
2281 				 * address currently exists.
2282 				 */
2283 				read_unlock_bh(&in6_dev->lock);
2284 				ipv6_create_tempaddr(ifp, NULL);
2285 			} else {
2286 				read_unlock_bh(&in6_dev->lock);
2287 			}
2288 
2289 			in6_ifa_put(ifp);
2290 			addrconf_verify(0);
2291 		}
2292 	}
2293 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2294 	in6_dev_put(in6_dev);
2295 }
2296 
2297 /*
2298  *	Set destination address.
2299  *	Special case for SIT interfaces where we create a new "virtual"
2300  *	device.
2301  */
2302 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2303 {
2304 	struct in6_ifreq ireq;
2305 	struct net_device *dev;
2306 	int err = -EINVAL;
2307 
2308 	rtnl_lock();
2309 
2310 	err = -EFAULT;
2311 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2312 		goto err_exit;
2313 
2314 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2315 
2316 	err = -ENODEV;
2317 	if (dev == NULL)
2318 		goto err_exit;
2319 
2320 #if IS_ENABLED(CONFIG_IPV6_SIT)
2321 	if (dev->type == ARPHRD_SIT) {
2322 		const struct net_device_ops *ops = dev->netdev_ops;
2323 		struct ifreq ifr;
2324 		struct ip_tunnel_parm p;
2325 
2326 		err = -EADDRNOTAVAIL;
2327 		if (!(ipv6_addr_type(&ireq.ifr6_addr) & IPV6_ADDR_COMPATv4))
2328 			goto err_exit;
2329 
2330 		memset(&p, 0, sizeof(p));
2331 		p.iph.daddr = ireq.ifr6_addr.s6_addr32[3];
2332 		p.iph.saddr = 0;
2333 		p.iph.version = 4;
2334 		p.iph.ihl = 5;
2335 		p.iph.protocol = IPPROTO_IPV6;
2336 		p.iph.ttl = 64;
2337 		ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
2338 
2339 		if (ops->ndo_do_ioctl) {
2340 			mm_segment_t oldfs = get_fs();
2341 
2342 			set_fs(KERNEL_DS);
2343 			err = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
2344 			set_fs(oldfs);
2345 		} else
2346 			err = -EOPNOTSUPP;
2347 
2348 		if (err == 0) {
2349 			err = -ENOBUFS;
2350 			dev = __dev_get_by_name(net, p.name);
2351 			if (!dev)
2352 				goto err_exit;
2353 			err = dev_open(dev);
2354 		}
2355 	}
2356 #endif
2357 
2358 err_exit:
2359 	rtnl_unlock();
2360 	return err;
2361 }
2362 
2363 /*
2364  *	Manual configuration of address on an interface
2365  */
2366 static int inet6_addr_add(struct net *net, int ifindex, const struct in6_addr *pfx,
2367 			  const struct in6_addr *peer_pfx,
2368 			  unsigned int plen, __u8 ifa_flags, __u32 prefered_lft,
2369 			  __u32 valid_lft)
2370 {
2371 	struct inet6_ifaddr *ifp;
2372 	struct inet6_dev *idev;
2373 	struct net_device *dev;
2374 	int scope;
2375 	u32 flags;
2376 	clock_t expires;
2377 	unsigned long timeout;
2378 
2379 	ASSERT_RTNL();
2380 
2381 	if (plen > 128)
2382 		return -EINVAL;
2383 
2384 	/* check the lifetime */
2385 	if (!valid_lft || prefered_lft > valid_lft)
2386 		return -EINVAL;
2387 
2388 	dev = __dev_get_by_index(net, ifindex);
2389 	if (!dev)
2390 		return -ENODEV;
2391 
2392 	idev = addrconf_add_dev(dev);
2393 	if (IS_ERR(idev))
2394 		return PTR_ERR(idev);
2395 
2396 	scope = ipv6_addr_scope(pfx);
2397 
2398 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
2399 	if (addrconf_finite_timeout(timeout)) {
2400 		expires = jiffies_to_clock_t(timeout * HZ);
2401 		valid_lft = timeout;
2402 		flags = RTF_EXPIRES;
2403 	} else {
2404 		expires = 0;
2405 		flags = 0;
2406 		ifa_flags |= IFA_F_PERMANENT;
2407 	}
2408 
2409 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
2410 	if (addrconf_finite_timeout(timeout)) {
2411 		if (timeout == 0)
2412 			ifa_flags |= IFA_F_DEPRECATED;
2413 		prefered_lft = timeout;
2414 	}
2415 
2416 	ifp = ipv6_add_addr(idev, pfx, peer_pfx, plen, scope, ifa_flags,
2417 			    valid_lft, prefered_lft);
2418 
2419 	if (!IS_ERR(ifp)) {
2420 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, dev,
2421 				      expires, flags);
2422 		/*
2423 		 * Note that section 3.1 of RFC 4429 indicates
2424 		 * that the Optimistic flag should not be set for
2425 		 * manually configured addresses
2426 		 */
2427 		addrconf_dad_start(ifp);
2428 		in6_ifa_put(ifp);
2429 		addrconf_verify(0);
2430 		return 0;
2431 	}
2432 
2433 	return PTR_ERR(ifp);
2434 }
2435 
2436 static int inet6_addr_del(struct net *net, int ifindex, const struct in6_addr *pfx,
2437 			  unsigned int plen)
2438 {
2439 	struct inet6_ifaddr *ifp;
2440 	struct inet6_dev *idev;
2441 	struct net_device *dev;
2442 
2443 	if (plen > 128)
2444 		return -EINVAL;
2445 
2446 	dev = __dev_get_by_index(net, ifindex);
2447 	if (!dev)
2448 		return -ENODEV;
2449 
2450 	if ((idev = __in6_dev_get(dev)) == NULL)
2451 		return -ENXIO;
2452 
2453 	read_lock_bh(&idev->lock);
2454 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
2455 		if (ifp->prefix_len == plen &&
2456 		    ipv6_addr_equal(pfx, &ifp->addr)) {
2457 			in6_ifa_hold(ifp);
2458 			read_unlock_bh(&idev->lock);
2459 
2460 			ipv6_del_addr(ifp);
2461 			return 0;
2462 		}
2463 	}
2464 	read_unlock_bh(&idev->lock);
2465 	return -EADDRNOTAVAIL;
2466 }
2467 
2468 
2469 int addrconf_add_ifaddr(struct net *net, void __user *arg)
2470 {
2471 	struct in6_ifreq ireq;
2472 	int err;
2473 
2474 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2475 		return -EPERM;
2476 
2477 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2478 		return -EFAULT;
2479 
2480 	rtnl_lock();
2481 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &ireq.ifr6_addr, NULL,
2482 			     ireq.ifr6_prefixlen, IFA_F_PERMANENT,
2483 			     INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
2484 	rtnl_unlock();
2485 	return err;
2486 }
2487 
2488 int addrconf_del_ifaddr(struct net *net, void __user *arg)
2489 {
2490 	struct in6_ifreq ireq;
2491 	int err;
2492 
2493 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2494 		return -EPERM;
2495 
2496 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2497 		return -EFAULT;
2498 
2499 	rtnl_lock();
2500 	err = inet6_addr_del(net, ireq.ifr6_ifindex, &ireq.ifr6_addr,
2501 			     ireq.ifr6_prefixlen);
2502 	rtnl_unlock();
2503 	return err;
2504 }
2505 
2506 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
2507 		     int plen, int scope)
2508 {
2509 	struct inet6_ifaddr *ifp;
2510 
2511 	ifp = ipv6_add_addr(idev, addr, NULL, plen,
2512 			    scope, IFA_F_PERMANENT,
2513 			    INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
2514 	if (!IS_ERR(ifp)) {
2515 		spin_lock_bh(&ifp->lock);
2516 		ifp->flags &= ~IFA_F_TENTATIVE;
2517 		spin_unlock_bh(&ifp->lock);
2518 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
2519 		in6_ifa_put(ifp);
2520 	}
2521 }
2522 
2523 #if IS_ENABLED(CONFIG_IPV6_SIT)
2524 static void sit_add_v4_addrs(struct inet6_dev *idev)
2525 {
2526 	struct in6_addr addr;
2527 	struct net_device *dev;
2528 	struct net *net = dev_net(idev->dev);
2529 	int scope, plen;
2530 	u32 pflags = 0;
2531 
2532 	ASSERT_RTNL();
2533 
2534 	memset(&addr, 0, sizeof(struct in6_addr));
2535 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
2536 
2537 	if (idev->dev->flags&IFF_POINTOPOINT) {
2538 		addr.s6_addr32[0] = htonl(0xfe800000);
2539 		scope = IFA_LINK;
2540 		plen = 64;
2541 	} else {
2542 		scope = IPV6_ADDR_COMPATv4;
2543 		plen = 96;
2544 		pflags |= RTF_NONEXTHOP;
2545 	}
2546 
2547 	if (addr.s6_addr32[3]) {
2548 		add_addr(idev, &addr, plen, scope);
2549 		addrconf_prefix_route(&addr, plen, idev->dev, 0, pflags);
2550 		return;
2551 	}
2552 
2553 	for_each_netdev(net, dev) {
2554 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
2555 		if (in_dev && (dev->flags & IFF_UP)) {
2556 			struct in_ifaddr *ifa;
2557 
2558 			int flag = scope;
2559 
2560 			for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
2561 
2562 				addr.s6_addr32[3] = ifa->ifa_local;
2563 
2564 				if (ifa->ifa_scope == RT_SCOPE_LINK)
2565 					continue;
2566 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
2567 					if (idev->dev->flags&IFF_POINTOPOINT)
2568 						continue;
2569 					flag |= IFA_HOST;
2570 				}
2571 
2572 				add_addr(idev, &addr, plen, flag);
2573 				addrconf_prefix_route(&addr, plen, idev->dev, 0,
2574 						      pflags);
2575 			}
2576 		}
2577 	}
2578 }
2579 #endif
2580 
2581 static void init_loopback(struct net_device *dev)
2582 {
2583 	struct inet6_dev  *idev;
2584 	struct net_device *sp_dev;
2585 	struct inet6_ifaddr *sp_ifa;
2586 	struct rt6_info *sp_rt;
2587 
2588 	/* ::1 */
2589 
2590 	ASSERT_RTNL();
2591 
2592 	if ((idev = ipv6_find_idev(dev)) == NULL) {
2593 		pr_debug("%s: add_dev failed\n", __func__);
2594 		return;
2595 	}
2596 
2597 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST);
2598 
2599 	/* Add routes to other interface's IPv6 addresses */
2600 	for_each_netdev(dev_net(dev), sp_dev) {
2601 		if (!strcmp(sp_dev->name, dev->name))
2602 			continue;
2603 
2604 		idev = __in6_dev_get(sp_dev);
2605 		if (!idev)
2606 			continue;
2607 
2608 		read_lock_bh(&idev->lock);
2609 		list_for_each_entry(sp_ifa, &idev->addr_list, if_list) {
2610 
2611 			if (sp_ifa->flags & (IFA_F_DADFAILED | IFA_F_TENTATIVE))
2612 				continue;
2613 
2614 			if (sp_ifa->rt)
2615 				continue;
2616 
2617 			sp_rt = addrconf_dst_alloc(idev, &sp_ifa->addr, false);
2618 
2619 			/* Failure cases are ignored */
2620 			if (!IS_ERR(sp_rt)) {
2621 				sp_ifa->rt = sp_rt;
2622 				ip6_ins_rt(sp_rt);
2623 			}
2624 		}
2625 		read_unlock_bh(&idev->lock);
2626 	}
2627 }
2628 
2629 static void addrconf_add_linklocal(struct inet6_dev *idev, const struct in6_addr *addr)
2630 {
2631 	struct inet6_ifaddr *ifp;
2632 	u32 addr_flags = IFA_F_PERMANENT;
2633 
2634 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2635 	if (idev->cnf.optimistic_dad &&
2636 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
2637 		addr_flags |= IFA_F_OPTIMISTIC;
2638 #endif
2639 
2640 
2641 	ifp = ipv6_add_addr(idev, addr, NULL, 64, IFA_LINK, addr_flags,
2642 			    INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
2643 	if (!IS_ERR(ifp)) {
2644 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, idev->dev, 0, 0);
2645 		addrconf_dad_start(ifp);
2646 		in6_ifa_put(ifp);
2647 	}
2648 }
2649 
2650 static void addrconf_dev_config(struct net_device *dev)
2651 {
2652 	struct in6_addr addr;
2653 	struct inet6_dev *idev;
2654 
2655 	ASSERT_RTNL();
2656 
2657 	if ((dev->type != ARPHRD_ETHER) &&
2658 	    (dev->type != ARPHRD_FDDI) &&
2659 	    (dev->type != ARPHRD_ARCNET) &&
2660 	    (dev->type != ARPHRD_INFINIBAND) &&
2661 	    (dev->type != ARPHRD_IEEE802154) &&
2662 	    (dev->type != ARPHRD_IEEE1394) &&
2663 	    (dev->type != ARPHRD_TUNNEL6)) {
2664 		/* Alas, we support only Ethernet autoconfiguration. */
2665 		return;
2666 	}
2667 
2668 	idev = addrconf_add_dev(dev);
2669 	if (IS_ERR(idev))
2670 		return;
2671 
2672 	memset(&addr, 0, sizeof(struct in6_addr));
2673 	addr.s6_addr32[0] = htonl(0xFE800000);
2674 
2675 	if (ipv6_generate_eui64(addr.s6_addr + 8, dev) == 0)
2676 		addrconf_add_linklocal(idev, &addr);
2677 }
2678 
2679 #if IS_ENABLED(CONFIG_IPV6_SIT)
2680 static void addrconf_sit_config(struct net_device *dev)
2681 {
2682 	struct inet6_dev *idev;
2683 
2684 	ASSERT_RTNL();
2685 
2686 	/*
2687 	 * Configure the tunnel with one of our IPv4
2688 	 * addresses... we should configure all of
2689 	 * our v4 addrs in the tunnel
2690 	 */
2691 
2692 	if ((idev = ipv6_find_idev(dev)) == NULL) {
2693 		pr_debug("%s: add_dev failed\n", __func__);
2694 		return;
2695 	}
2696 
2697 	if (dev->priv_flags & IFF_ISATAP) {
2698 		struct in6_addr addr;
2699 
2700 		ipv6_addr_set(&addr,  htonl(0xFE800000), 0, 0, 0);
2701 		if (!ipv6_generate_eui64(addr.s6_addr + 8, dev))
2702 			addrconf_add_linklocal(idev, &addr);
2703 		return;
2704 	}
2705 
2706 	sit_add_v4_addrs(idev);
2707 
2708 	if (dev->flags&IFF_POINTOPOINT)
2709 		addrconf_add_mroute(dev);
2710 }
2711 #endif
2712 
2713 #if IS_ENABLED(CONFIG_NET_IPGRE)
2714 static void addrconf_gre_config(struct net_device *dev)
2715 {
2716 	struct inet6_dev *idev;
2717 	struct in6_addr addr;
2718 
2719 	ASSERT_RTNL();
2720 
2721 	if ((idev = ipv6_find_idev(dev)) == NULL) {
2722 		pr_debug("%s: add_dev failed\n", __func__);
2723 		return;
2724 	}
2725 
2726 	ipv6_addr_set(&addr,  htonl(0xFE800000), 0, 0, 0);
2727 	if (!ipv6_generate_eui64(addr.s6_addr + 8, dev))
2728 		addrconf_add_linklocal(idev, &addr);
2729 }
2730 #endif
2731 
2732 static inline int
2733 ipv6_inherit_linklocal(struct inet6_dev *idev, struct net_device *link_dev)
2734 {
2735 	struct in6_addr lladdr;
2736 
2737 	if (!ipv6_get_lladdr(link_dev, &lladdr, IFA_F_TENTATIVE)) {
2738 		addrconf_add_linklocal(idev, &lladdr);
2739 		return 0;
2740 	}
2741 	return -1;
2742 }
2743 
2744 static int addrconf_notify(struct notifier_block *this, unsigned long event,
2745 			   void *ptr)
2746 {
2747 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
2748 	struct inet6_dev *idev = __in6_dev_get(dev);
2749 	int run_pending = 0;
2750 	int err;
2751 
2752 	switch (event) {
2753 	case NETDEV_REGISTER:
2754 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
2755 			idev = ipv6_add_dev(dev);
2756 			if (!idev)
2757 				return notifier_from_errno(-ENOMEM);
2758 		}
2759 		break;
2760 
2761 	case NETDEV_UP:
2762 	case NETDEV_CHANGE:
2763 		if (dev->flags & IFF_SLAVE)
2764 			break;
2765 
2766 		if (event == NETDEV_UP) {
2767 			if (!addrconf_qdisc_ok(dev)) {
2768 				/* device is not ready yet. */
2769 				pr_info("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
2770 					dev->name);
2771 				break;
2772 			}
2773 
2774 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
2775 				idev = ipv6_add_dev(dev);
2776 
2777 			if (idev) {
2778 				idev->if_flags |= IF_READY;
2779 				run_pending = 1;
2780 			}
2781 		} else {
2782 			if (!addrconf_qdisc_ok(dev)) {
2783 				/* device is still not ready. */
2784 				break;
2785 			}
2786 
2787 			if (idev) {
2788 				if (idev->if_flags & IF_READY)
2789 					/* device is already configured. */
2790 					break;
2791 				idev->if_flags |= IF_READY;
2792 			}
2793 
2794 			pr_info("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
2795 				dev->name);
2796 
2797 			run_pending = 1;
2798 		}
2799 
2800 		switch (dev->type) {
2801 #if IS_ENABLED(CONFIG_IPV6_SIT)
2802 		case ARPHRD_SIT:
2803 			addrconf_sit_config(dev);
2804 			break;
2805 #endif
2806 #if IS_ENABLED(CONFIG_NET_IPGRE)
2807 		case ARPHRD_IPGRE:
2808 			addrconf_gre_config(dev);
2809 			break;
2810 #endif
2811 		case ARPHRD_LOOPBACK:
2812 			init_loopback(dev);
2813 			break;
2814 
2815 		default:
2816 			addrconf_dev_config(dev);
2817 			break;
2818 		}
2819 
2820 		if (idev) {
2821 			if (run_pending)
2822 				addrconf_dad_run(idev);
2823 
2824 			/*
2825 			 * If the MTU changed during the interface down,
2826 			 * when the interface up, the changed MTU must be
2827 			 * reflected in the idev as well as routers.
2828 			 */
2829 			if (idev->cnf.mtu6 != dev->mtu &&
2830 			    dev->mtu >= IPV6_MIN_MTU) {
2831 				rt6_mtu_change(dev, dev->mtu);
2832 				idev->cnf.mtu6 = dev->mtu;
2833 			}
2834 			idev->tstamp = jiffies;
2835 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
2836 
2837 			/*
2838 			 * If the changed mtu during down is lower than
2839 			 * IPV6_MIN_MTU stop IPv6 on this interface.
2840 			 */
2841 			if (dev->mtu < IPV6_MIN_MTU)
2842 				addrconf_ifdown(dev, 1);
2843 		}
2844 		break;
2845 
2846 	case NETDEV_CHANGEMTU:
2847 		if (idev && dev->mtu >= IPV6_MIN_MTU) {
2848 			rt6_mtu_change(dev, dev->mtu);
2849 			idev->cnf.mtu6 = dev->mtu;
2850 			break;
2851 		}
2852 
2853 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
2854 			idev = ipv6_add_dev(dev);
2855 			if (idev)
2856 				break;
2857 		}
2858 
2859 		/*
2860 		 * MTU falled under IPV6_MIN_MTU.
2861 		 * Stop IPv6 on this interface.
2862 		 */
2863 
2864 	case NETDEV_DOWN:
2865 	case NETDEV_UNREGISTER:
2866 		/*
2867 		 *	Remove all addresses from this interface.
2868 		 */
2869 		addrconf_ifdown(dev, event != NETDEV_DOWN);
2870 		break;
2871 
2872 	case NETDEV_CHANGENAME:
2873 		if (idev) {
2874 			snmp6_unregister_dev(idev);
2875 			addrconf_sysctl_unregister(idev);
2876 			addrconf_sysctl_register(idev);
2877 			err = snmp6_register_dev(idev);
2878 			if (err)
2879 				return notifier_from_errno(err);
2880 		}
2881 		break;
2882 
2883 	case NETDEV_PRE_TYPE_CHANGE:
2884 	case NETDEV_POST_TYPE_CHANGE:
2885 		addrconf_type_change(dev, event);
2886 		break;
2887 	}
2888 
2889 	return NOTIFY_OK;
2890 }
2891 
2892 /*
2893  *	addrconf module should be notified of a device going up
2894  */
2895 static struct notifier_block ipv6_dev_notf = {
2896 	.notifier_call = addrconf_notify,
2897 };
2898 
2899 static void addrconf_type_change(struct net_device *dev, unsigned long event)
2900 {
2901 	struct inet6_dev *idev;
2902 	ASSERT_RTNL();
2903 
2904 	idev = __in6_dev_get(dev);
2905 
2906 	if (event == NETDEV_POST_TYPE_CHANGE)
2907 		ipv6_mc_remap(idev);
2908 	else if (event == NETDEV_PRE_TYPE_CHANGE)
2909 		ipv6_mc_unmap(idev);
2910 }
2911 
2912 static int addrconf_ifdown(struct net_device *dev, int how)
2913 {
2914 	struct net *net = dev_net(dev);
2915 	struct inet6_dev *idev;
2916 	struct inet6_ifaddr *ifa;
2917 	int state, i;
2918 
2919 	ASSERT_RTNL();
2920 
2921 	rt6_ifdown(net, dev);
2922 	neigh_ifdown(&nd_tbl, dev);
2923 
2924 	idev = __in6_dev_get(dev);
2925 	if (idev == NULL)
2926 		return -ENODEV;
2927 
2928 	/*
2929 	 * Step 1: remove reference to ipv6 device from parent device.
2930 	 *	   Do not dev_put!
2931 	 */
2932 	if (how) {
2933 		idev->dead = 1;
2934 
2935 		/* protected by rtnl_lock */
2936 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
2937 
2938 		/* Step 1.5: remove snmp6 entry */
2939 		snmp6_unregister_dev(idev);
2940 
2941 	}
2942 
2943 	/* Step 2: clear hash table */
2944 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
2945 		struct hlist_head *h = &inet6_addr_lst[i];
2946 
2947 		spin_lock_bh(&addrconf_hash_lock);
2948 	restart:
2949 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
2950 			if (ifa->idev == idev) {
2951 				hlist_del_init_rcu(&ifa->addr_lst);
2952 				addrconf_del_dad_timer(ifa);
2953 				goto restart;
2954 			}
2955 		}
2956 		spin_unlock_bh(&addrconf_hash_lock);
2957 	}
2958 
2959 	write_lock_bh(&idev->lock);
2960 
2961 	addrconf_del_rs_timer(idev);
2962 
2963 	/* Step 2: clear flags for stateless addrconf */
2964 	if (!how)
2965 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
2966 
2967 	if (how && del_timer(&idev->regen_timer))
2968 		in6_dev_put(idev);
2969 
2970 	/* Step 3: clear tempaddr list */
2971 	while (!list_empty(&idev->tempaddr_list)) {
2972 		ifa = list_first_entry(&idev->tempaddr_list,
2973 				       struct inet6_ifaddr, tmp_list);
2974 		list_del(&ifa->tmp_list);
2975 		write_unlock_bh(&idev->lock);
2976 		spin_lock_bh(&ifa->lock);
2977 
2978 		if (ifa->ifpub) {
2979 			in6_ifa_put(ifa->ifpub);
2980 			ifa->ifpub = NULL;
2981 		}
2982 		spin_unlock_bh(&ifa->lock);
2983 		in6_ifa_put(ifa);
2984 		write_lock_bh(&idev->lock);
2985 	}
2986 
2987 	while (!list_empty(&idev->addr_list)) {
2988 		ifa = list_first_entry(&idev->addr_list,
2989 				       struct inet6_ifaddr, if_list);
2990 		addrconf_del_dad_timer(ifa);
2991 
2992 		list_del(&ifa->if_list);
2993 
2994 		write_unlock_bh(&idev->lock);
2995 
2996 		spin_lock_bh(&ifa->state_lock);
2997 		state = ifa->state;
2998 		ifa->state = INET6_IFADDR_STATE_DEAD;
2999 		spin_unlock_bh(&ifa->state_lock);
3000 
3001 		if (state != INET6_IFADDR_STATE_DEAD) {
3002 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
3003 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
3004 		}
3005 		in6_ifa_put(ifa);
3006 
3007 		write_lock_bh(&idev->lock);
3008 	}
3009 
3010 	write_unlock_bh(&idev->lock);
3011 
3012 	/* Step 5: Discard multicast list */
3013 	if (how)
3014 		ipv6_mc_destroy_dev(idev);
3015 	else
3016 		ipv6_mc_down(idev);
3017 
3018 	idev->tstamp = jiffies;
3019 
3020 	/* Last: Shot the device (if unregistered) */
3021 	if (how) {
3022 		addrconf_sysctl_unregister(idev);
3023 		neigh_parms_release(&nd_tbl, idev->nd_parms);
3024 		neigh_ifdown(&nd_tbl, dev);
3025 		in6_dev_put(idev);
3026 	}
3027 	return 0;
3028 }
3029 
3030 static void addrconf_rs_timer(unsigned long data)
3031 {
3032 	struct inet6_dev *idev = (struct inet6_dev *)data;
3033 	struct net_device *dev = idev->dev;
3034 	struct in6_addr lladdr;
3035 
3036 	write_lock(&idev->lock);
3037 	if (idev->dead || !(idev->if_flags & IF_READY))
3038 		goto out;
3039 
3040 	if (!ipv6_accept_ra(idev))
3041 		goto out;
3042 
3043 	/* Announcement received after solicitation was sent */
3044 	if (idev->if_flags & IF_RA_RCVD)
3045 		goto out;
3046 
3047 	if (idev->rs_probes++ < idev->cnf.rtr_solicits) {
3048 		write_unlock(&idev->lock);
3049 		if (!ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
3050 			ndisc_send_rs(dev, &lladdr,
3051 				      &in6addr_linklocal_allrouters);
3052 		else
3053 			goto put;
3054 
3055 		write_lock(&idev->lock);
3056 		/* The wait after the last probe can be shorter */
3057 		addrconf_mod_rs_timer(idev, (idev->rs_probes ==
3058 					     idev->cnf.rtr_solicits) ?
3059 				      idev->cnf.rtr_solicit_delay :
3060 				      idev->cnf.rtr_solicit_interval);
3061 	} else {
3062 		/*
3063 		 * Note: we do not support deprecated "all on-link"
3064 		 * assumption any longer.
3065 		 */
3066 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
3067 	}
3068 
3069 out:
3070 	write_unlock(&idev->lock);
3071 put:
3072 	in6_dev_put(idev);
3073 }
3074 
3075 /*
3076  *	Duplicate Address Detection
3077  */
3078 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
3079 {
3080 	unsigned long rand_num;
3081 	struct inet6_dev *idev = ifp->idev;
3082 
3083 	if (ifp->flags & IFA_F_OPTIMISTIC)
3084 		rand_num = 0;
3085 	else
3086 		rand_num = net_random() % (idev->cnf.rtr_solicit_delay ? : 1);
3087 
3088 	ifp->dad_probes = idev->cnf.dad_transmits;
3089 	addrconf_mod_dad_timer(ifp, rand_num);
3090 }
3091 
3092 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
3093 {
3094 	struct inet6_dev *idev = ifp->idev;
3095 	struct net_device *dev = idev->dev;
3096 
3097 	addrconf_join_solict(dev, &ifp->addr);
3098 
3099 	net_srandom(ifp->addr.s6_addr32[3]);
3100 
3101 	read_lock_bh(&idev->lock);
3102 	spin_lock(&ifp->lock);
3103 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
3104 		goto out;
3105 
3106 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
3107 	    idev->cnf.accept_dad < 1 ||
3108 	    !(ifp->flags&IFA_F_TENTATIVE) ||
3109 	    ifp->flags & IFA_F_NODAD) {
3110 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3111 		spin_unlock(&ifp->lock);
3112 		read_unlock_bh(&idev->lock);
3113 
3114 		addrconf_dad_completed(ifp);
3115 		return;
3116 	}
3117 
3118 	if (!(idev->if_flags & IF_READY)) {
3119 		spin_unlock(&ifp->lock);
3120 		read_unlock_bh(&idev->lock);
3121 		/*
3122 		 * If the device is not ready:
3123 		 * - keep it tentative if it is a permanent address.
3124 		 * - otherwise, kill it.
3125 		 */
3126 		in6_ifa_hold(ifp);
3127 		addrconf_dad_stop(ifp, 0);
3128 		return;
3129 	}
3130 
3131 	/*
3132 	 * Optimistic nodes can start receiving
3133 	 * Frames right away
3134 	 */
3135 	if (ifp->flags & IFA_F_OPTIMISTIC)
3136 		ip6_ins_rt(ifp->rt);
3137 
3138 	addrconf_dad_kick(ifp);
3139 out:
3140 	spin_unlock(&ifp->lock);
3141 	read_unlock_bh(&idev->lock);
3142 }
3143 
3144 static void addrconf_dad_timer(unsigned long data)
3145 {
3146 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *) data;
3147 	struct inet6_dev *idev = ifp->idev;
3148 	struct in6_addr mcaddr;
3149 
3150 	if (!ifp->dad_probes && addrconf_dad_end(ifp))
3151 		goto out;
3152 
3153 	write_lock(&idev->lock);
3154 	if (idev->dead || !(idev->if_flags & IF_READY)) {
3155 		write_unlock(&idev->lock);
3156 		goto out;
3157 	}
3158 
3159 	spin_lock(&ifp->lock);
3160 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
3161 		spin_unlock(&ifp->lock);
3162 		write_unlock(&idev->lock);
3163 		goto out;
3164 	}
3165 
3166 	if (ifp->dad_probes == 0) {
3167 		/*
3168 		 * DAD was successful
3169 		 */
3170 
3171 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3172 		spin_unlock(&ifp->lock);
3173 		write_unlock(&idev->lock);
3174 
3175 		addrconf_dad_completed(ifp);
3176 
3177 		goto out;
3178 	}
3179 
3180 	ifp->dad_probes--;
3181 	addrconf_mod_dad_timer(ifp, ifp->idev->nd_parms->retrans_time);
3182 	spin_unlock(&ifp->lock);
3183 	write_unlock(&idev->lock);
3184 
3185 	/* send a neighbour solicitation for our addr */
3186 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
3187 	ndisc_send_ns(ifp->idev->dev, NULL, &ifp->addr, &mcaddr, &in6addr_any);
3188 out:
3189 	in6_ifa_put(ifp);
3190 }
3191 
3192 static void addrconf_dad_completed(struct inet6_ifaddr *ifp)
3193 {
3194 	struct net_device *dev = ifp->idev->dev;
3195 	struct in6_addr lladdr;
3196 	bool send_rs, send_mld;
3197 
3198 	addrconf_del_dad_timer(ifp);
3199 
3200 	/*
3201 	 *	Configure the address for reception. Now it is valid.
3202 	 */
3203 
3204 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
3205 
3206 	/* If added prefix is link local and we are prepared to process
3207 	   router advertisements, start sending router solicitations.
3208 	 */
3209 
3210 	read_lock_bh(&ifp->idev->lock);
3211 	spin_lock(&ifp->lock);
3212 	send_mld = ipv6_addr_type(&ifp->addr) & IPV6_ADDR_LINKLOCAL &&
3213 		   ifp->idev->valid_ll_addr_cnt == 1;
3214 	send_rs = send_mld &&
3215 		  ipv6_accept_ra(ifp->idev) &&
3216 		  ifp->idev->cnf.rtr_solicits > 0 &&
3217 		  (dev->flags&IFF_LOOPBACK) == 0;
3218 	spin_unlock(&ifp->lock);
3219 	read_unlock_bh(&ifp->idev->lock);
3220 
3221 	/* While dad is in progress mld report's source address is in6_addrany.
3222 	 * Resend with proper ll now.
3223 	 */
3224 	if (send_mld)
3225 		ipv6_mc_dad_complete(ifp->idev);
3226 
3227 	if (send_rs) {
3228 		/*
3229 		 *	If a host as already performed a random delay
3230 		 *	[...] as part of DAD [...] there is no need
3231 		 *	to delay again before sending the first RS
3232 		 */
3233 		if (ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
3234 			return;
3235 		ndisc_send_rs(dev, &lladdr, &in6addr_linklocal_allrouters);
3236 
3237 		write_lock_bh(&ifp->idev->lock);
3238 		spin_lock(&ifp->lock);
3239 		ifp->idev->rs_probes = 1;
3240 		ifp->idev->if_flags |= IF_RS_SENT;
3241 		addrconf_mod_rs_timer(ifp->idev,
3242 				      ifp->idev->cnf.rtr_solicit_interval);
3243 		spin_unlock(&ifp->lock);
3244 		write_unlock_bh(&ifp->idev->lock);
3245 	}
3246 }
3247 
3248 static void addrconf_dad_run(struct inet6_dev *idev)
3249 {
3250 	struct inet6_ifaddr *ifp;
3251 
3252 	read_lock_bh(&idev->lock);
3253 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
3254 		spin_lock(&ifp->lock);
3255 		if (ifp->flags & IFA_F_TENTATIVE &&
3256 		    ifp->state == INET6_IFADDR_STATE_DAD)
3257 			addrconf_dad_kick(ifp);
3258 		spin_unlock(&ifp->lock);
3259 	}
3260 	read_unlock_bh(&idev->lock);
3261 }
3262 
3263 #ifdef CONFIG_PROC_FS
3264 struct if6_iter_state {
3265 	struct seq_net_private p;
3266 	int bucket;
3267 	int offset;
3268 };
3269 
3270 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
3271 {
3272 	struct inet6_ifaddr *ifa = NULL;
3273 	struct if6_iter_state *state = seq->private;
3274 	struct net *net = seq_file_net(seq);
3275 	int p = 0;
3276 
3277 	/* initial bucket if pos is 0 */
3278 	if (pos == 0) {
3279 		state->bucket = 0;
3280 		state->offset = 0;
3281 	}
3282 
3283 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
3284 		hlist_for_each_entry_rcu_bh(ifa, &inet6_addr_lst[state->bucket],
3285 					 addr_lst) {
3286 			if (!net_eq(dev_net(ifa->idev->dev), net))
3287 				continue;
3288 			/* sync with offset */
3289 			if (p < state->offset) {
3290 				p++;
3291 				continue;
3292 			}
3293 			state->offset++;
3294 			return ifa;
3295 		}
3296 
3297 		/* prepare for next bucket */
3298 		state->offset = 0;
3299 		p = 0;
3300 	}
3301 	return NULL;
3302 }
3303 
3304 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
3305 					 struct inet6_ifaddr *ifa)
3306 {
3307 	struct if6_iter_state *state = seq->private;
3308 	struct net *net = seq_file_net(seq);
3309 
3310 	hlist_for_each_entry_continue_rcu_bh(ifa, addr_lst) {
3311 		if (!net_eq(dev_net(ifa->idev->dev), net))
3312 			continue;
3313 		state->offset++;
3314 		return ifa;
3315 	}
3316 
3317 	while (++state->bucket < IN6_ADDR_HSIZE) {
3318 		state->offset = 0;
3319 		hlist_for_each_entry_rcu_bh(ifa,
3320 				     &inet6_addr_lst[state->bucket], addr_lst) {
3321 			if (!net_eq(dev_net(ifa->idev->dev), net))
3322 				continue;
3323 			state->offset++;
3324 			return ifa;
3325 		}
3326 	}
3327 
3328 	return NULL;
3329 }
3330 
3331 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
3332 	__acquires(rcu_bh)
3333 {
3334 	rcu_read_lock_bh();
3335 	return if6_get_first(seq, *pos);
3336 }
3337 
3338 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3339 {
3340 	struct inet6_ifaddr *ifa;
3341 
3342 	ifa = if6_get_next(seq, v);
3343 	++*pos;
3344 	return ifa;
3345 }
3346 
3347 static void if6_seq_stop(struct seq_file *seq, void *v)
3348 	__releases(rcu_bh)
3349 {
3350 	rcu_read_unlock_bh();
3351 }
3352 
3353 static int if6_seq_show(struct seq_file *seq, void *v)
3354 {
3355 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
3356 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
3357 		   &ifp->addr,
3358 		   ifp->idev->dev->ifindex,
3359 		   ifp->prefix_len,
3360 		   ifp->scope,
3361 		   ifp->flags,
3362 		   ifp->idev->dev->name);
3363 	return 0;
3364 }
3365 
3366 static const struct seq_operations if6_seq_ops = {
3367 	.start	= if6_seq_start,
3368 	.next	= if6_seq_next,
3369 	.show	= if6_seq_show,
3370 	.stop	= if6_seq_stop,
3371 };
3372 
3373 static int if6_seq_open(struct inode *inode, struct file *file)
3374 {
3375 	return seq_open_net(inode, file, &if6_seq_ops,
3376 			    sizeof(struct if6_iter_state));
3377 }
3378 
3379 static const struct file_operations if6_fops = {
3380 	.owner		= THIS_MODULE,
3381 	.open		= if6_seq_open,
3382 	.read		= seq_read,
3383 	.llseek		= seq_lseek,
3384 	.release	= seq_release_net,
3385 };
3386 
3387 static int __net_init if6_proc_net_init(struct net *net)
3388 {
3389 	if (!proc_create("if_inet6", S_IRUGO, net->proc_net, &if6_fops))
3390 		return -ENOMEM;
3391 	return 0;
3392 }
3393 
3394 static void __net_exit if6_proc_net_exit(struct net *net)
3395 {
3396 	remove_proc_entry("if_inet6", net->proc_net);
3397 }
3398 
3399 static struct pernet_operations if6_proc_net_ops = {
3400        .init = if6_proc_net_init,
3401        .exit = if6_proc_net_exit,
3402 };
3403 
3404 int __init if6_proc_init(void)
3405 {
3406 	return register_pernet_subsys(&if6_proc_net_ops);
3407 }
3408 
3409 void if6_proc_exit(void)
3410 {
3411 	unregister_pernet_subsys(&if6_proc_net_ops);
3412 }
3413 #endif	/* CONFIG_PROC_FS */
3414 
3415 #if IS_ENABLED(CONFIG_IPV6_MIP6)
3416 /* Check if address is a home address configured on any interface. */
3417 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
3418 {
3419 	int ret = 0;
3420 	struct inet6_ifaddr *ifp = NULL;
3421 	unsigned int hash = inet6_addr_hash(addr);
3422 
3423 	rcu_read_lock_bh();
3424 	hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[hash], addr_lst) {
3425 		if (!net_eq(dev_net(ifp->idev->dev), net))
3426 			continue;
3427 		if (ipv6_addr_equal(&ifp->addr, addr) &&
3428 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
3429 			ret = 1;
3430 			break;
3431 		}
3432 	}
3433 	rcu_read_unlock_bh();
3434 	return ret;
3435 }
3436 #endif
3437 
3438 /*
3439  *	Periodic address status verification
3440  */
3441 
3442 static void addrconf_verify(unsigned long foo)
3443 {
3444 	unsigned long now, next, next_sec, next_sched;
3445 	struct inet6_ifaddr *ifp;
3446 	int i;
3447 
3448 	rcu_read_lock_bh();
3449 	spin_lock(&addrconf_verify_lock);
3450 	now = jiffies;
3451 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
3452 
3453 	del_timer(&addr_chk_timer);
3454 
3455 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3456 restart:
3457 		hlist_for_each_entry_rcu_bh(ifp,
3458 					 &inet6_addr_lst[i], addr_lst) {
3459 			unsigned long age;
3460 
3461 			/* When setting preferred_lft to a value not zero or
3462 			 * infinity, while valid_lft is infinity
3463 			 * IFA_F_PERMANENT has a non-infinity life time.
3464 			 */
3465 			if ((ifp->flags & IFA_F_PERMANENT) &&
3466 			    (ifp->prefered_lft == INFINITY_LIFE_TIME))
3467 				continue;
3468 
3469 			spin_lock(&ifp->lock);
3470 			/* We try to batch several events at once. */
3471 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
3472 
3473 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
3474 			    age >= ifp->valid_lft) {
3475 				spin_unlock(&ifp->lock);
3476 				in6_ifa_hold(ifp);
3477 				ipv6_del_addr(ifp);
3478 				goto restart;
3479 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
3480 				spin_unlock(&ifp->lock);
3481 				continue;
3482 			} else if (age >= ifp->prefered_lft) {
3483 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
3484 				int deprecate = 0;
3485 
3486 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
3487 					deprecate = 1;
3488 					ifp->flags |= IFA_F_DEPRECATED;
3489 				}
3490 
3491 				if ((ifp->valid_lft != INFINITY_LIFE_TIME) &&
3492 				    (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)))
3493 					next = ifp->tstamp + ifp->valid_lft * HZ;
3494 
3495 				spin_unlock(&ifp->lock);
3496 
3497 				if (deprecate) {
3498 					in6_ifa_hold(ifp);
3499 
3500 					ipv6_ifa_notify(0, ifp);
3501 					in6_ifa_put(ifp);
3502 					goto restart;
3503 				}
3504 			} else if ((ifp->flags&IFA_F_TEMPORARY) &&
3505 				   !(ifp->flags&IFA_F_TENTATIVE)) {
3506 				unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
3507 					ifp->idev->cnf.dad_transmits *
3508 					ifp->idev->nd_parms->retrans_time / HZ;
3509 
3510 				if (age >= ifp->prefered_lft - regen_advance) {
3511 					struct inet6_ifaddr *ifpub = ifp->ifpub;
3512 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
3513 						next = ifp->tstamp + ifp->prefered_lft * HZ;
3514 					if (!ifp->regen_count && ifpub) {
3515 						ifp->regen_count++;
3516 						in6_ifa_hold(ifp);
3517 						in6_ifa_hold(ifpub);
3518 						spin_unlock(&ifp->lock);
3519 
3520 						spin_lock(&ifpub->lock);
3521 						ifpub->regen_count = 0;
3522 						spin_unlock(&ifpub->lock);
3523 						ipv6_create_tempaddr(ifpub, ifp);
3524 						in6_ifa_put(ifpub);
3525 						in6_ifa_put(ifp);
3526 						goto restart;
3527 					}
3528 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
3529 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
3530 				spin_unlock(&ifp->lock);
3531 			} else {
3532 				/* ifp->prefered_lft <= ifp->valid_lft */
3533 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
3534 					next = ifp->tstamp + ifp->prefered_lft * HZ;
3535 				spin_unlock(&ifp->lock);
3536 			}
3537 		}
3538 	}
3539 
3540 	next_sec = round_jiffies_up(next);
3541 	next_sched = next;
3542 
3543 	/* If rounded timeout is accurate enough, accept it. */
3544 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
3545 		next_sched = next_sec;
3546 
3547 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
3548 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
3549 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
3550 
3551 	ADBG(KERN_DEBUG "now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
3552 	      now, next, next_sec, next_sched);
3553 
3554 	addr_chk_timer.expires = next_sched;
3555 	add_timer(&addr_chk_timer);
3556 	spin_unlock(&addrconf_verify_lock);
3557 	rcu_read_unlock_bh();
3558 }
3559 
3560 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
3561 				     struct in6_addr **peer_pfx)
3562 {
3563 	struct in6_addr *pfx = NULL;
3564 
3565 	*peer_pfx = NULL;
3566 
3567 	if (addr)
3568 		pfx = nla_data(addr);
3569 
3570 	if (local) {
3571 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
3572 			*peer_pfx = pfx;
3573 		pfx = nla_data(local);
3574 	}
3575 
3576 	return pfx;
3577 }
3578 
3579 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
3580 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
3581 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
3582 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
3583 };
3584 
3585 static int
3586 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh)
3587 {
3588 	struct net *net = sock_net(skb->sk);
3589 	struct ifaddrmsg *ifm;
3590 	struct nlattr *tb[IFA_MAX+1];
3591 	struct in6_addr *pfx, *peer_pfx;
3592 	int err;
3593 
3594 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
3595 	if (err < 0)
3596 		return err;
3597 
3598 	ifm = nlmsg_data(nlh);
3599 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
3600 	if (pfx == NULL)
3601 		return -EINVAL;
3602 
3603 	return inet6_addr_del(net, ifm->ifa_index, pfx, ifm->ifa_prefixlen);
3604 }
3605 
3606 static int inet6_addr_modify(struct inet6_ifaddr *ifp, u8 ifa_flags,
3607 			     u32 prefered_lft, u32 valid_lft)
3608 {
3609 	u32 flags;
3610 	clock_t expires;
3611 	unsigned long timeout;
3612 
3613 	if (!valid_lft || (prefered_lft > valid_lft))
3614 		return -EINVAL;
3615 
3616 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
3617 	if (addrconf_finite_timeout(timeout)) {
3618 		expires = jiffies_to_clock_t(timeout * HZ);
3619 		valid_lft = timeout;
3620 		flags = RTF_EXPIRES;
3621 	} else {
3622 		expires = 0;
3623 		flags = 0;
3624 		ifa_flags |= IFA_F_PERMANENT;
3625 	}
3626 
3627 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
3628 	if (addrconf_finite_timeout(timeout)) {
3629 		if (timeout == 0)
3630 			ifa_flags |= IFA_F_DEPRECATED;
3631 		prefered_lft = timeout;
3632 	}
3633 
3634 	spin_lock_bh(&ifp->lock);
3635 	ifp->flags = (ifp->flags & ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD | IFA_F_HOMEADDRESS)) | ifa_flags;
3636 	ifp->tstamp = jiffies;
3637 	ifp->valid_lft = valid_lft;
3638 	ifp->prefered_lft = prefered_lft;
3639 
3640 	spin_unlock_bh(&ifp->lock);
3641 	if (!(ifp->flags&IFA_F_TENTATIVE))
3642 		ipv6_ifa_notify(0, ifp);
3643 
3644 	addrconf_prefix_route(&ifp->addr, ifp->prefix_len, ifp->idev->dev,
3645 			      expires, flags);
3646 	addrconf_verify(0);
3647 
3648 	return 0;
3649 }
3650 
3651 static int
3652 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh)
3653 {
3654 	struct net *net = sock_net(skb->sk);
3655 	struct ifaddrmsg *ifm;
3656 	struct nlattr *tb[IFA_MAX+1];
3657 	struct in6_addr *pfx, *peer_pfx;
3658 	struct inet6_ifaddr *ifa;
3659 	struct net_device *dev;
3660 	u32 valid_lft = INFINITY_LIFE_TIME, preferred_lft = INFINITY_LIFE_TIME;
3661 	u8 ifa_flags;
3662 	int err;
3663 
3664 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
3665 	if (err < 0)
3666 		return err;
3667 
3668 	ifm = nlmsg_data(nlh);
3669 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
3670 	if (pfx == NULL)
3671 		return -EINVAL;
3672 
3673 	if (tb[IFA_CACHEINFO]) {
3674 		struct ifa_cacheinfo *ci;
3675 
3676 		ci = nla_data(tb[IFA_CACHEINFO]);
3677 		valid_lft = ci->ifa_valid;
3678 		preferred_lft = ci->ifa_prefered;
3679 	} else {
3680 		preferred_lft = INFINITY_LIFE_TIME;
3681 		valid_lft = INFINITY_LIFE_TIME;
3682 	}
3683 
3684 	dev =  __dev_get_by_index(net, ifm->ifa_index);
3685 	if (dev == NULL)
3686 		return -ENODEV;
3687 
3688 	/* We ignore other flags so far. */
3689 	ifa_flags = ifm->ifa_flags & (IFA_F_NODAD | IFA_F_HOMEADDRESS);
3690 
3691 	ifa = ipv6_get_ifaddr(net, pfx, dev, 1);
3692 	if (ifa == NULL) {
3693 		/*
3694 		 * It would be best to check for !NLM_F_CREATE here but
3695 		 * userspace alreay relies on not having to provide this.
3696 		 */
3697 		return inet6_addr_add(net, ifm->ifa_index, pfx, peer_pfx,
3698 				      ifm->ifa_prefixlen, ifa_flags,
3699 				      preferred_lft, valid_lft);
3700 	}
3701 
3702 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
3703 	    !(nlh->nlmsg_flags & NLM_F_REPLACE))
3704 		err = -EEXIST;
3705 	else
3706 		err = inet6_addr_modify(ifa, ifa_flags, preferred_lft, valid_lft);
3707 
3708 	in6_ifa_put(ifa);
3709 
3710 	return err;
3711 }
3712 
3713 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u8 flags,
3714 			  u8 scope, int ifindex)
3715 {
3716 	struct ifaddrmsg *ifm;
3717 
3718 	ifm = nlmsg_data(nlh);
3719 	ifm->ifa_family = AF_INET6;
3720 	ifm->ifa_prefixlen = prefixlen;
3721 	ifm->ifa_flags = flags;
3722 	ifm->ifa_scope = scope;
3723 	ifm->ifa_index = ifindex;
3724 }
3725 
3726 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
3727 			 unsigned long tstamp, u32 preferred, u32 valid)
3728 {
3729 	struct ifa_cacheinfo ci;
3730 
3731 	ci.cstamp = cstamp_delta(cstamp);
3732 	ci.tstamp = cstamp_delta(tstamp);
3733 	ci.ifa_prefered = preferred;
3734 	ci.ifa_valid = valid;
3735 
3736 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
3737 }
3738 
3739 static inline int rt_scope(int ifa_scope)
3740 {
3741 	if (ifa_scope & IFA_HOST)
3742 		return RT_SCOPE_HOST;
3743 	else if (ifa_scope & IFA_LINK)
3744 		return RT_SCOPE_LINK;
3745 	else if (ifa_scope & IFA_SITE)
3746 		return RT_SCOPE_SITE;
3747 	else
3748 		return RT_SCOPE_UNIVERSE;
3749 }
3750 
3751 static inline int inet6_ifaddr_msgsize(void)
3752 {
3753 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
3754 	       + nla_total_size(16) /* IFA_LOCAL */
3755 	       + nla_total_size(16) /* IFA_ADDRESS */
3756 	       + nla_total_size(sizeof(struct ifa_cacheinfo));
3757 }
3758 
3759 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
3760 			     u32 portid, u32 seq, int event, unsigned int flags)
3761 {
3762 	struct nlmsghdr  *nlh;
3763 	u32 preferred, valid;
3764 
3765 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
3766 	if (nlh == NULL)
3767 		return -EMSGSIZE;
3768 
3769 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
3770 		      ifa->idev->dev->ifindex);
3771 
3772 	if (!((ifa->flags&IFA_F_PERMANENT) &&
3773 	      (ifa->prefered_lft == INFINITY_LIFE_TIME))) {
3774 		preferred = ifa->prefered_lft;
3775 		valid = ifa->valid_lft;
3776 		if (preferred != INFINITY_LIFE_TIME) {
3777 			long tval = (jiffies - ifa->tstamp)/HZ;
3778 			if (preferred > tval)
3779 				preferred -= tval;
3780 			else
3781 				preferred = 0;
3782 			if (valid != INFINITY_LIFE_TIME) {
3783 				if (valid > tval)
3784 					valid -= tval;
3785 				else
3786 					valid = 0;
3787 			}
3788 		}
3789 	} else {
3790 		preferred = INFINITY_LIFE_TIME;
3791 		valid = INFINITY_LIFE_TIME;
3792 	}
3793 
3794 	if (!ipv6_addr_any(&ifa->peer_addr)) {
3795 		if (nla_put(skb, IFA_LOCAL, 16, &ifa->addr) < 0 ||
3796 		    nla_put(skb, IFA_ADDRESS, 16, &ifa->peer_addr) < 0)
3797 			goto error;
3798 	} else
3799 		if (nla_put(skb, IFA_ADDRESS, 16, &ifa->addr) < 0)
3800 			goto error;
3801 
3802 	if (put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0)
3803 		goto error;
3804 
3805 	return nlmsg_end(skb, nlh);
3806 
3807 error:
3808 	nlmsg_cancel(skb, nlh);
3809 	return -EMSGSIZE;
3810 }
3811 
3812 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
3813 				u32 portid, u32 seq, int event, u16 flags)
3814 {
3815 	struct nlmsghdr  *nlh;
3816 	u8 scope = RT_SCOPE_UNIVERSE;
3817 	int ifindex = ifmca->idev->dev->ifindex;
3818 
3819 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
3820 		scope = RT_SCOPE_SITE;
3821 
3822 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
3823 	if (nlh == NULL)
3824 		return -EMSGSIZE;
3825 
3826 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
3827 	if (nla_put(skb, IFA_MULTICAST, 16, &ifmca->mca_addr) < 0 ||
3828 	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
3829 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
3830 		nlmsg_cancel(skb, nlh);
3831 		return -EMSGSIZE;
3832 	}
3833 
3834 	return nlmsg_end(skb, nlh);
3835 }
3836 
3837 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
3838 				u32 portid, u32 seq, int event, unsigned int flags)
3839 {
3840 	struct nlmsghdr  *nlh;
3841 	u8 scope = RT_SCOPE_UNIVERSE;
3842 	int ifindex = ifaca->aca_idev->dev->ifindex;
3843 
3844 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
3845 		scope = RT_SCOPE_SITE;
3846 
3847 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
3848 	if (nlh == NULL)
3849 		return -EMSGSIZE;
3850 
3851 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
3852 	if (nla_put(skb, IFA_ANYCAST, 16, &ifaca->aca_addr) < 0 ||
3853 	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
3854 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
3855 		nlmsg_cancel(skb, nlh);
3856 		return -EMSGSIZE;
3857 	}
3858 
3859 	return nlmsg_end(skb, nlh);
3860 }
3861 
3862 enum addr_type_t {
3863 	UNICAST_ADDR,
3864 	MULTICAST_ADDR,
3865 	ANYCAST_ADDR,
3866 };
3867 
3868 /* called with rcu_read_lock() */
3869 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
3870 			  struct netlink_callback *cb, enum addr_type_t type,
3871 			  int s_ip_idx, int *p_ip_idx)
3872 {
3873 	struct ifmcaddr6 *ifmca;
3874 	struct ifacaddr6 *ifaca;
3875 	int err = 1;
3876 	int ip_idx = *p_ip_idx;
3877 
3878 	read_lock_bh(&idev->lock);
3879 	switch (type) {
3880 	case UNICAST_ADDR: {
3881 		struct inet6_ifaddr *ifa;
3882 
3883 		/* unicast address incl. temp addr */
3884 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
3885 			if (++ip_idx < s_ip_idx)
3886 				continue;
3887 			err = inet6_fill_ifaddr(skb, ifa,
3888 						NETLINK_CB(cb->skb).portid,
3889 						cb->nlh->nlmsg_seq,
3890 						RTM_NEWADDR,
3891 						NLM_F_MULTI);
3892 			if (err <= 0)
3893 				break;
3894 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
3895 		}
3896 		break;
3897 	}
3898 	case MULTICAST_ADDR:
3899 		/* multicast address */
3900 		for (ifmca = idev->mc_list; ifmca;
3901 		     ifmca = ifmca->next, ip_idx++) {
3902 			if (ip_idx < s_ip_idx)
3903 				continue;
3904 			err = inet6_fill_ifmcaddr(skb, ifmca,
3905 						  NETLINK_CB(cb->skb).portid,
3906 						  cb->nlh->nlmsg_seq,
3907 						  RTM_GETMULTICAST,
3908 						  NLM_F_MULTI);
3909 			if (err <= 0)
3910 				break;
3911 		}
3912 		break;
3913 	case ANYCAST_ADDR:
3914 		/* anycast address */
3915 		for (ifaca = idev->ac_list; ifaca;
3916 		     ifaca = ifaca->aca_next, ip_idx++) {
3917 			if (ip_idx < s_ip_idx)
3918 				continue;
3919 			err = inet6_fill_ifacaddr(skb, ifaca,
3920 						  NETLINK_CB(cb->skb).portid,
3921 						  cb->nlh->nlmsg_seq,
3922 						  RTM_GETANYCAST,
3923 						  NLM_F_MULTI);
3924 			if (err <= 0)
3925 				break;
3926 		}
3927 		break;
3928 	default:
3929 		break;
3930 	}
3931 	read_unlock_bh(&idev->lock);
3932 	*p_ip_idx = ip_idx;
3933 	return err;
3934 }
3935 
3936 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
3937 			   enum addr_type_t type)
3938 {
3939 	struct net *net = sock_net(skb->sk);
3940 	int h, s_h;
3941 	int idx, ip_idx;
3942 	int s_idx, s_ip_idx;
3943 	struct net_device *dev;
3944 	struct inet6_dev *idev;
3945 	struct hlist_head *head;
3946 
3947 	s_h = cb->args[0];
3948 	s_idx = idx = cb->args[1];
3949 	s_ip_idx = ip_idx = cb->args[2];
3950 
3951 	rcu_read_lock();
3952 	cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^ net->dev_base_seq;
3953 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
3954 		idx = 0;
3955 		head = &net->dev_index_head[h];
3956 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
3957 			if (idx < s_idx)
3958 				goto cont;
3959 			if (h > s_h || idx > s_idx)
3960 				s_ip_idx = 0;
3961 			ip_idx = 0;
3962 			idev = __in6_dev_get(dev);
3963 			if (!idev)
3964 				goto cont;
3965 
3966 			if (in6_dump_addrs(idev, skb, cb, type,
3967 					   s_ip_idx, &ip_idx) <= 0)
3968 				goto done;
3969 cont:
3970 			idx++;
3971 		}
3972 	}
3973 done:
3974 	rcu_read_unlock();
3975 	cb->args[0] = h;
3976 	cb->args[1] = idx;
3977 	cb->args[2] = ip_idx;
3978 
3979 	return skb->len;
3980 }
3981 
3982 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
3983 {
3984 	enum addr_type_t type = UNICAST_ADDR;
3985 
3986 	return inet6_dump_addr(skb, cb, type);
3987 }
3988 
3989 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
3990 {
3991 	enum addr_type_t type = MULTICAST_ADDR;
3992 
3993 	return inet6_dump_addr(skb, cb, type);
3994 }
3995 
3996 
3997 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
3998 {
3999 	enum addr_type_t type = ANYCAST_ADDR;
4000 
4001 	return inet6_dump_addr(skb, cb, type);
4002 }
4003 
4004 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh)
4005 {
4006 	struct net *net = sock_net(in_skb->sk);
4007 	struct ifaddrmsg *ifm;
4008 	struct nlattr *tb[IFA_MAX+1];
4009 	struct in6_addr *addr = NULL, *peer;
4010 	struct net_device *dev = NULL;
4011 	struct inet6_ifaddr *ifa;
4012 	struct sk_buff *skb;
4013 	int err;
4014 
4015 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
4016 	if (err < 0)
4017 		goto errout;
4018 
4019 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
4020 	if (addr == NULL) {
4021 		err = -EINVAL;
4022 		goto errout;
4023 	}
4024 
4025 	ifm = nlmsg_data(nlh);
4026 	if (ifm->ifa_index)
4027 		dev = __dev_get_by_index(net, ifm->ifa_index);
4028 
4029 	ifa = ipv6_get_ifaddr(net, addr, dev, 1);
4030 	if (!ifa) {
4031 		err = -EADDRNOTAVAIL;
4032 		goto errout;
4033 	}
4034 
4035 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
4036 	if (!skb) {
4037 		err = -ENOBUFS;
4038 		goto errout_ifa;
4039 	}
4040 
4041 	err = inet6_fill_ifaddr(skb, ifa, NETLINK_CB(in_skb).portid,
4042 				nlh->nlmsg_seq, RTM_NEWADDR, 0);
4043 	if (err < 0) {
4044 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
4045 		WARN_ON(err == -EMSGSIZE);
4046 		kfree_skb(skb);
4047 		goto errout_ifa;
4048 	}
4049 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
4050 errout_ifa:
4051 	in6_ifa_put(ifa);
4052 errout:
4053 	return err;
4054 }
4055 
4056 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
4057 {
4058 	struct sk_buff *skb;
4059 	struct net *net = dev_net(ifa->idev->dev);
4060 	int err = -ENOBUFS;
4061 
4062 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
4063 	if (skb == NULL)
4064 		goto errout;
4065 
4066 	err = inet6_fill_ifaddr(skb, ifa, 0, 0, event, 0);
4067 	if (err < 0) {
4068 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
4069 		WARN_ON(err == -EMSGSIZE);
4070 		kfree_skb(skb);
4071 		goto errout;
4072 	}
4073 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
4074 	return;
4075 errout:
4076 	if (err < 0)
4077 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
4078 }
4079 
4080 static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
4081 				__s32 *array, int bytes)
4082 {
4083 	BUG_ON(bytes < (DEVCONF_MAX * 4));
4084 
4085 	memset(array, 0, bytes);
4086 	array[DEVCONF_FORWARDING] = cnf->forwarding;
4087 	array[DEVCONF_HOPLIMIT] = cnf->hop_limit;
4088 	array[DEVCONF_MTU6] = cnf->mtu6;
4089 	array[DEVCONF_ACCEPT_RA] = cnf->accept_ra;
4090 	array[DEVCONF_ACCEPT_REDIRECTS] = cnf->accept_redirects;
4091 	array[DEVCONF_AUTOCONF] = cnf->autoconf;
4092 	array[DEVCONF_DAD_TRANSMITS] = cnf->dad_transmits;
4093 	array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
4094 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
4095 		jiffies_to_msecs(cnf->rtr_solicit_interval);
4096 	array[DEVCONF_RTR_SOLICIT_DELAY] =
4097 		jiffies_to_msecs(cnf->rtr_solicit_delay);
4098 	array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;
4099 	array[DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL] =
4100 		jiffies_to_msecs(cnf->mldv1_unsolicited_report_interval);
4101 	array[DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL] =
4102 		jiffies_to_msecs(cnf->mldv2_unsolicited_report_interval);
4103 	array[DEVCONF_USE_TEMPADDR] = cnf->use_tempaddr;
4104 	array[DEVCONF_TEMP_VALID_LFT] = cnf->temp_valid_lft;
4105 	array[DEVCONF_TEMP_PREFERED_LFT] = cnf->temp_prefered_lft;
4106 	array[DEVCONF_REGEN_MAX_RETRY] = cnf->regen_max_retry;
4107 	array[DEVCONF_MAX_DESYNC_FACTOR] = cnf->max_desync_factor;
4108 	array[DEVCONF_MAX_ADDRESSES] = cnf->max_addresses;
4109 	array[DEVCONF_ACCEPT_RA_DEFRTR] = cnf->accept_ra_defrtr;
4110 	array[DEVCONF_ACCEPT_RA_PINFO] = cnf->accept_ra_pinfo;
4111 #ifdef CONFIG_IPV6_ROUTER_PREF
4112 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = cnf->accept_ra_rtr_pref;
4113 	array[DEVCONF_RTR_PROBE_INTERVAL] =
4114 		jiffies_to_msecs(cnf->rtr_probe_interval);
4115 #ifdef CONFIG_IPV6_ROUTE_INFO
4116 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
4117 #endif
4118 #endif
4119 	array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
4120 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
4121 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
4122 	array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
4123 #endif
4124 #ifdef CONFIG_IPV6_MROUTE
4125 	array[DEVCONF_MC_FORWARDING] = cnf->mc_forwarding;
4126 #endif
4127 	array[DEVCONF_DISABLE_IPV6] = cnf->disable_ipv6;
4128 	array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad;
4129 	array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao;
4130 	array[DEVCONF_NDISC_NOTIFY] = cnf->ndisc_notify;
4131 	array[DEVCONF_SUPPRESS_FRAG_NDISC] = cnf->suppress_frag_ndisc;
4132 }
4133 
4134 static inline size_t inet6_ifla6_size(void)
4135 {
4136 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
4137 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
4138 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
4139 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
4140 	     + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
4141 	     + nla_total_size(sizeof(struct in6_addr)); /* IFLA_INET6_TOKEN */
4142 }
4143 
4144 static inline size_t inet6_if_nlmsg_size(void)
4145 {
4146 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
4147 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
4148 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
4149 	       + nla_total_size(4) /* IFLA_MTU */
4150 	       + nla_total_size(4) /* IFLA_LINK */
4151 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
4152 }
4153 
4154 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
4155 				      int items, int bytes)
4156 {
4157 	int i;
4158 	int pad = bytes - sizeof(u64) * items;
4159 	BUG_ON(pad < 0);
4160 
4161 	/* Use put_unaligned() because stats may not be aligned for u64. */
4162 	put_unaligned(items, &stats[0]);
4163 	for (i = 1; i < items; i++)
4164 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
4165 
4166 	memset(&stats[items], 0, pad);
4167 }
4168 
4169 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu **mib,
4170 				      int items, int bytes, size_t syncpoff)
4171 {
4172 	int i;
4173 	int pad = bytes - sizeof(u64) * items;
4174 	BUG_ON(pad < 0);
4175 
4176 	/* Use put_unaligned() because stats may not be aligned for u64. */
4177 	put_unaligned(items, &stats[0]);
4178 	for (i = 1; i < items; i++)
4179 		put_unaligned(snmp_fold_field64(mib, i, syncpoff), &stats[i]);
4180 
4181 	memset(&stats[items], 0, pad);
4182 }
4183 
4184 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
4185 			     int bytes)
4186 {
4187 	switch (attrtype) {
4188 	case IFLA_INET6_STATS:
4189 		__snmp6_fill_stats64(stats, (void __percpu **)idev->stats.ipv6,
4190 				     IPSTATS_MIB_MAX, bytes, offsetof(struct ipstats_mib, syncp));
4191 		break;
4192 	case IFLA_INET6_ICMP6STATS:
4193 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, ICMP6_MIB_MAX, bytes);
4194 		break;
4195 	}
4196 }
4197 
4198 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev)
4199 {
4200 	struct nlattr *nla;
4201 	struct ifla_cacheinfo ci;
4202 
4203 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, idev->if_flags))
4204 		goto nla_put_failure;
4205 	ci.max_reasm_len = IPV6_MAXPLEN;
4206 	ci.tstamp = cstamp_delta(idev->tstamp);
4207 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
4208 	ci.retrans_time = jiffies_to_msecs(idev->nd_parms->retrans_time);
4209 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
4210 		goto nla_put_failure;
4211 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
4212 	if (nla == NULL)
4213 		goto nla_put_failure;
4214 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
4215 
4216 	/* XXX - MC not implemented */
4217 
4218 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
4219 	if (nla == NULL)
4220 		goto nla_put_failure;
4221 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
4222 
4223 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
4224 	if (nla == NULL)
4225 		goto nla_put_failure;
4226 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
4227 
4228 	nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
4229 	if (nla == NULL)
4230 		goto nla_put_failure;
4231 	read_lock_bh(&idev->lock);
4232 	memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
4233 	read_unlock_bh(&idev->lock);
4234 
4235 	return 0;
4236 
4237 nla_put_failure:
4238 	return -EMSGSIZE;
4239 }
4240 
4241 static size_t inet6_get_link_af_size(const struct net_device *dev)
4242 {
4243 	if (!__in6_dev_get(dev))
4244 		return 0;
4245 
4246 	return inet6_ifla6_size();
4247 }
4248 
4249 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev)
4250 {
4251 	struct inet6_dev *idev = __in6_dev_get(dev);
4252 
4253 	if (!idev)
4254 		return -ENODATA;
4255 
4256 	if (inet6_fill_ifla6_attrs(skb, idev) < 0)
4257 		return -EMSGSIZE;
4258 
4259 	return 0;
4260 }
4261 
4262 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token)
4263 {
4264 	struct inet6_ifaddr *ifp;
4265 	struct net_device *dev = idev->dev;
4266 	bool update_rs = false;
4267 	struct in6_addr ll_addr;
4268 
4269 	if (token == NULL)
4270 		return -EINVAL;
4271 	if (ipv6_addr_any(token))
4272 		return -EINVAL;
4273 	if (dev->flags & (IFF_LOOPBACK | IFF_NOARP))
4274 		return -EINVAL;
4275 	if (!ipv6_accept_ra(idev))
4276 		return -EINVAL;
4277 	if (idev->cnf.rtr_solicits <= 0)
4278 		return -EINVAL;
4279 
4280 	write_lock_bh(&idev->lock);
4281 
4282 	BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
4283 	memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
4284 
4285 	write_unlock_bh(&idev->lock);
4286 
4287 	if (!idev->dead && (idev->if_flags & IF_READY) &&
4288 	    !ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
4289 			     IFA_F_OPTIMISTIC)) {
4290 
4291 		/* If we're not ready, then normal ifup will take care
4292 		 * of this. Otherwise, we need to request our rs here.
4293 		 */
4294 		ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
4295 		update_rs = true;
4296 	}
4297 
4298 	write_lock_bh(&idev->lock);
4299 
4300 	if (update_rs) {
4301 		idev->if_flags |= IF_RS_SENT;
4302 		idev->rs_probes = 1;
4303 		addrconf_mod_rs_timer(idev, idev->cnf.rtr_solicit_interval);
4304 	}
4305 
4306 	/* Well, that's kinda nasty ... */
4307 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
4308 		spin_lock(&ifp->lock);
4309 		if (ifp->tokenized) {
4310 			ifp->valid_lft = 0;
4311 			ifp->prefered_lft = 0;
4312 		}
4313 		spin_unlock(&ifp->lock);
4314 	}
4315 
4316 	write_unlock_bh(&idev->lock);
4317 	addrconf_verify(0);
4318 	return 0;
4319 }
4320 
4321 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla)
4322 {
4323 	int err = -EINVAL;
4324 	struct inet6_dev *idev = __in6_dev_get(dev);
4325 	struct nlattr *tb[IFLA_INET6_MAX + 1];
4326 
4327 	if (!idev)
4328 		return -EAFNOSUPPORT;
4329 
4330 	if (nla_parse_nested(tb, IFLA_INET6_MAX, nla, NULL) < 0)
4331 		BUG();
4332 
4333 	if (tb[IFLA_INET6_TOKEN])
4334 		err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]));
4335 
4336 	return err;
4337 }
4338 
4339 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
4340 			     u32 portid, u32 seq, int event, unsigned int flags)
4341 {
4342 	struct net_device *dev = idev->dev;
4343 	struct ifinfomsg *hdr;
4344 	struct nlmsghdr *nlh;
4345 	void *protoinfo;
4346 
4347 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
4348 	if (nlh == NULL)
4349 		return -EMSGSIZE;
4350 
4351 	hdr = nlmsg_data(nlh);
4352 	hdr->ifi_family = AF_INET6;
4353 	hdr->__ifi_pad = 0;
4354 	hdr->ifi_type = dev->type;
4355 	hdr->ifi_index = dev->ifindex;
4356 	hdr->ifi_flags = dev_get_flags(dev);
4357 	hdr->ifi_change = 0;
4358 
4359 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
4360 	    (dev->addr_len &&
4361 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
4362 	    nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
4363 	    (dev->ifindex != dev->iflink &&
4364 	     nla_put_u32(skb, IFLA_LINK, dev->iflink)))
4365 		goto nla_put_failure;
4366 	protoinfo = nla_nest_start(skb, IFLA_PROTINFO);
4367 	if (protoinfo == NULL)
4368 		goto nla_put_failure;
4369 
4370 	if (inet6_fill_ifla6_attrs(skb, idev) < 0)
4371 		goto nla_put_failure;
4372 
4373 	nla_nest_end(skb, protoinfo);
4374 	return nlmsg_end(skb, nlh);
4375 
4376 nla_put_failure:
4377 	nlmsg_cancel(skb, nlh);
4378 	return -EMSGSIZE;
4379 }
4380 
4381 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
4382 {
4383 	struct net *net = sock_net(skb->sk);
4384 	int h, s_h;
4385 	int idx = 0, s_idx;
4386 	struct net_device *dev;
4387 	struct inet6_dev *idev;
4388 	struct hlist_head *head;
4389 
4390 	s_h = cb->args[0];
4391 	s_idx = cb->args[1];
4392 
4393 	rcu_read_lock();
4394 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
4395 		idx = 0;
4396 		head = &net->dev_index_head[h];
4397 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
4398 			if (idx < s_idx)
4399 				goto cont;
4400 			idev = __in6_dev_get(dev);
4401 			if (!idev)
4402 				goto cont;
4403 			if (inet6_fill_ifinfo(skb, idev,
4404 					      NETLINK_CB(cb->skb).portid,
4405 					      cb->nlh->nlmsg_seq,
4406 					      RTM_NEWLINK, NLM_F_MULTI) <= 0)
4407 				goto out;
4408 cont:
4409 			idx++;
4410 		}
4411 	}
4412 out:
4413 	rcu_read_unlock();
4414 	cb->args[1] = idx;
4415 	cb->args[0] = h;
4416 
4417 	return skb->len;
4418 }
4419 
4420 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
4421 {
4422 	struct sk_buff *skb;
4423 	struct net *net = dev_net(idev->dev);
4424 	int err = -ENOBUFS;
4425 
4426 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
4427 	if (skb == NULL)
4428 		goto errout;
4429 
4430 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
4431 	if (err < 0) {
4432 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
4433 		WARN_ON(err == -EMSGSIZE);
4434 		kfree_skb(skb);
4435 		goto errout;
4436 	}
4437 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
4438 	return;
4439 errout:
4440 	if (err < 0)
4441 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
4442 }
4443 
4444 static inline size_t inet6_prefix_nlmsg_size(void)
4445 {
4446 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
4447 	       + nla_total_size(sizeof(struct in6_addr))
4448 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
4449 }
4450 
4451 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
4452 			     struct prefix_info *pinfo, u32 portid, u32 seq,
4453 			     int event, unsigned int flags)
4454 {
4455 	struct prefixmsg *pmsg;
4456 	struct nlmsghdr *nlh;
4457 	struct prefix_cacheinfo	ci;
4458 
4459 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
4460 	if (nlh == NULL)
4461 		return -EMSGSIZE;
4462 
4463 	pmsg = nlmsg_data(nlh);
4464 	pmsg->prefix_family = AF_INET6;
4465 	pmsg->prefix_pad1 = 0;
4466 	pmsg->prefix_pad2 = 0;
4467 	pmsg->prefix_ifindex = idev->dev->ifindex;
4468 	pmsg->prefix_len = pinfo->prefix_len;
4469 	pmsg->prefix_type = pinfo->type;
4470 	pmsg->prefix_pad3 = 0;
4471 	pmsg->prefix_flags = 0;
4472 	if (pinfo->onlink)
4473 		pmsg->prefix_flags |= IF_PREFIX_ONLINK;
4474 	if (pinfo->autoconf)
4475 		pmsg->prefix_flags |= IF_PREFIX_AUTOCONF;
4476 
4477 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
4478 		goto nla_put_failure;
4479 	ci.preferred_time = ntohl(pinfo->prefered);
4480 	ci.valid_time = ntohl(pinfo->valid);
4481 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
4482 		goto nla_put_failure;
4483 	return nlmsg_end(skb, nlh);
4484 
4485 nla_put_failure:
4486 	nlmsg_cancel(skb, nlh);
4487 	return -EMSGSIZE;
4488 }
4489 
4490 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
4491 			 struct prefix_info *pinfo)
4492 {
4493 	struct sk_buff *skb;
4494 	struct net *net = dev_net(idev->dev);
4495 	int err = -ENOBUFS;
4496 
4497 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
4498 	if (skb == NULL)
4499 		goto errout;
4500 
4501 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
4502 	if (err < 0) {
4503 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
4504 		WARN_ON(err == -EMSGSIZE);
4505 		kfree_skb(skb);
4506 		goto errout;
4507 	}
4508 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
4509 	return;
4510 errout:
4511 	if (err < 0)
4512 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
4513 }
4514 
4515 static void update_valid_ll_addr_cnt(struct inet6_ifaddr *ifp, int count)
4516 {
4517 	write_lock_bh(&ifp->idev->lock);
4518 	spin_lock(&ifp->lock);
4519 	if (((ifp->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|
4520 			    IFA_F_DADFAILED)) == IFA_F_PERMANENT) &&
4521 	    (ipv6_addr_type(&ifp->addr) & IPV6_ADDR_LINKLOCAL))
4522 		ifp->idev->valid_ll_addr_cnt += count;
4523 	WARN_ON(ifp->idev->valid_ll_addr_cnt < 0);
4524 	spin_unlock(&ifp->lock);
4525 	write_unlock_bh(&ifp->idev->lock);
4526 }
4527 
4528 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
4529 {
4530 	struct net *net = dev_net(ifp->idev->dev);
4531 
4532 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
4533 
4534 	switch (event) {
4535 	case RTM_NEWADDR:
4536 		update_valid_ll_addr_cnt(ifp, 1);
4537 
4538 		/*
4539 		 * If the address was optimistic
4540 		 * we inserted the route at the start of
4541 		 * our DAD process, so we don't need
4542 		 * to do it again
4543 		 */
4544 		if (!(ifp->rt->rt6i_node))
4545 			ip6_ins_rt(ifp->rt);
4546 		if (ifp->idev->cnf.forwarding)
4547 			addrconf_join_anycast(ifp);
4548 		if (!ipv6_addr_any(&ifp->peer_addr))
4549 			addrconf_prefix_route(&ifp->peer_addr, 128,
4550 					      ifp->idev->dev, 0, 0);
4551 		break;
4552 	case RTM_DELADDR:
4553 		update_valid_ll_addr_cnt(ifp, -1);
4554 
4555 		if (ifp->idev->cnf.forwarding)
4556 			addrconf_leave_anycast(ifp);
4557 		addrconf_leave_solict(ifp->idev, &ifp->addr);
4558 		if (!ipv6_addr_any(&ifp->peer_addr)) {
4559 			struct rt6_info *rt;
4560 			struct net_device *dev = ifp->idev->dev;
4561 
4562 			rt = rt6_lookup(dev_net(dev), &ifp->peer_addr, NULL,
4563 					dev->ifindex, 1);
4564 			if (rt) {
4565 				dst_hold(&rt->dst);
4566 				if (ip6_del_rt(rt))
4567 					dst_free(&rt->dst);
4568 			}
4569 		}
4570 		dst_hold(&ifp->rt->dst);
4571 
4572 		if (ip6_del_rt(ifp->rt))
4573 			dst_free(&ifp->rt->dst);
4574 		break;
4575 	}
4576 	atomic_inc(&net->ipv6.dev_addr_genid);
4577 	rt_genid_bump_ipv6(net);
4578 }
4579 
4580 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
4581 {
4582 	rcu_read_lock_bh();
4583 	if (likely(ifp->idev->dead == 0))
4584 		__ipv6_ifa_notify(event, ifp);
4585 	rcu_read_unlock_bh();
4586 }
4587 
4588 #ifdef CONFIG_SYSCTL
4589 
4590 static
4591 int addrconf_sysctl_forward(struct ctl_table *ctl, int write,
4592 			   void __user *buffer, size_t *lenp, loff_t *ppos)
4593 {
4594 	int *valp = ctl->data;
4595 	int val = *valp;
4596 	loff_t pos = *ppos;
4597 	struct ctl_table lctl;
4598 	int ret;
4599 
4600 	/*
4601 	 * ctl->data points to idev->cnf.forwarding, we should
4602 	 * not modify it until we get the rtnl lock.
4603 	 */
4604 	lctl = *ctl;
4605 	lctl.data = &val;
4606 
4607 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
4608 
4609 	if (write)
4610 		ret = addrconf_fixup_forwarding(ctl, valp, val);
4611 	if (ret)
4612 		*ppos = pos;
4613 	return ret;
4614 }
4615 
4616 static void dev_disable_change(struct inet6_dev *idev)
4617 {
4618 	struct netdev_notifier_info info;
4619 
4620 	if (!idev || !idev->dev)
4621 		return;
4622 
4623 	netdev_notifier_info_init(&info, idev->dev);
4624 	if (idev->cnf.disable_ipv6)
4625 		addrconf_notify(NULL, NETDEV_DOWN, &info);
4626 	else
4627 		addrconf_notify(NULL, NETDEV_UP, &info);
4628 }
4629 
4630 static void addrconf_disable_change(struct net *net, __s32 newf)
4631 {
4632 	struct net_device *dev;
4633 	struct inet6_dev *idev;
4634 
4635 	rcu_read_lock();
4636 	for_each_netdev_rcu(net, dev) {
4637 		idev = __in6_dev_get(dev);
4638 		if (idev) {
4639 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
4640 			idev->cnf.disable_ipv6 = newf;
4641 			if (changed)
4642 				dev_disable_change(idev);
4643 		}
4644 	}
4645 	rcu_read_unlock();
4646 }
4647 
4648 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
4649 {
4650 	struct net *net;
4651 	int old;
4652 
4653 	if (!rtnl_trylock())
4654 		return restart_syscall();
4655 
4656 	net = (struct net *)table->extra2;
4657 	old = *p;
4658 	*p = newf;
4659 
4660 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
4661 		rtnl_unlock();
4662 		return 0;
4663 	}
4664 
4665 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
4666 		net->ipv6.devconf_dflt->disable_ipv6 = newf;
4667 		addrconf_disable_change(net, newf);
4668 	} else if ((!newf) ^ (!old))
4669 		dev_disable_change((struct inet6_dev *)table->extra1);
4670 
4671 	rtnl_unlock();
4672 	return 0;
4673 }
4674 
4675 static
4676 int addrconf_sysctl_disable(struct ctl_table *ctl, int write,
4677 			    void __user *buffer, size_t *lenp, loff_t *ppos)
4678 {
4679 	int *valp = ctl->data;
4680 	int val = *valp;
4681 	loff_t pos = *ppos;
4682 	struct ctl_table lctl;
4683 	int ret;
4684 
4685 	/*
4686 	 * ctl->data points to idev->cnf.disable_ipv6, we should
4687 	 * not modify it until we get the rtnl lock.
4688 	 */
4689 	lctl = *ctl;
4690 	lctl.data = &val;
4691 
4692 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
4693 
4694 	if (write)
4695 		ret = addrconf_disable_ipv6(ctl, valp, val);
4696 	if (ret)
4697 		*ppos = pos;
4698 	return ret;
4699 }
4700 
4701 static struct addrconf_sysctl_table
4702 {
4703 	struct ctl_table_header *sysctl_header;
4704 	struct ctl_table addrconf_vars[DEVCONF_MAX+1];
4705 } addrconf_sysctl __read_mostly = {
4706 	.sysctl_header = NULL,
4707 	.addrconf_vars = {
4708 		{
4709 			.procname	= "forwarding",
4710 			.data		= &ipv6_devconf.forwarding,
4711 			.maxlen		= sizeof(int),
4712 			.mode		= 0644,
4713 			.proc_handler	= addrconf_sysctl_forward,
4714 		},
4715 		{
4716 			.procname	= "hop_limit",
4717 			.data		= &ipv6_devconf.hop_limit,
4718 			.maxlen		= sizeof(int),
4719 			.mode		= 0644,
4720 			.proc_handler	= proc_dointvec,
4721 		},
4722 		{
4723 			.procname	= "mtu",
4724 			.data		= &ipv6_devconf.mtu6,
4725 			.maxlen		= sizeof(int),
4726 			.mode		= 0644,
4727 			.proc_handler	= proc_dointvec,
4728 		},
4729 		{
4730 			.procname	= "accept_ra",
4731 			.data		= &ipv6_devconf.accept_ra,
4732 			.maxlen		= sizeof(int),
4733 			.mode		= 0644,
4734 			.proc_handler	= proc_dointvec,
4735 		},
4736 		{
4737 			.procname	= "accept_redirects",
4738 			.data		= &ipv6_devconf.accept_redirects,
4739 			.maxlen		= sizeof(int),
4740 			.mode		= 0644,
4741 			.proc_handler	= proc_dointvec,
4742 		},
4743 		{
4744 			.procname	= "autoconf",
4745 			.data		= &ipv6_devconf.autoconf,
4746 			.maxlen		= sizeof(int),
4747 			.mode		= 0644,
4748 			.proc_handler	= proc_dointvec,
4749 		},
4750 		{
4751 			.procname	= "dad_transmits",
4752 			.data		= &ipv6_devconf.dad_transmits,
4753 			.maxlen		= sizeof(int),
4754 			.mode		= 0644,
4755 			.proc_handler	= proc_dointvec,
4756 		},
4757 		{
4758 			.procname	= "router_solicitations",
4759 			.data		= &ipv6_devconf.rtr_solicits,
4760 			.maxlen		= sizeof(int),
4761 			.mode		= 0644,
4762 			.proc_handler	= proc_dointvec,
4763 		},
4764 		{
4765 			.procname	= "router_solicitation_interval",
4766 			.data		= &ipv6_devconf.rtr_solicit_interval,
4767 			.maxlen		= sizeof(int),
4768 			.mode		= 0644,
4769 			.proc_handler	= proc_dointvec_jiffies,
4770 		},
4771 		{
4772 			.procname	= "router_solicitation_delay",
4773 			.data		= &ipv6_devconf.rtr_solicit_delay,
4774 			.maxlen		= sizeof(int),
4775 			.mode		= 0644,
4776 			.proc_handler	= proc_dointvec_jiffies,
4777 		},
4778 		{
4779 			.procname	= "force_mld_version",
4780 			.data		= &ipv6_devconf.force_mld_version,
4781 			.maxlen		= sizeof(int),
4782 			.mode		= 0644,
4783 			.proc_handler	= proc_dointvec,
4784 		},
4785 		{
4786 			.procname	= "mldv1_unsolicited_report_interval",
4787 			.data		=
4788 				&ipv6_devconf.mldv1_unsolicited_report_interval,
4789 			.maxlen		= sizeof(int),
4790 			.mode		= 0644,
4791 			.proc_handler	= proc_dointvec_ms_jiffies,
4792 		},
4793 		{
4794 			.procname	= "mldv2_unsolicited_report_interval",
4795 			.data		=
4796 				&ipv6_devconf.mldv2_unsolicited_report_interval,
4797 			.maxlen		= sizeof(int),
4798 			.mode		= 0644,
4799 			.proc_handler	= proc_dointvec_ms_jiffies,
4800 		},
4801 		{
4802 			.procname	= "use_tempaddr",
4803 			.data		= &ipv6_devconf.use_tempaddr,
4804 			.maxlen		= sizeof(int),
4805 			.mode		= 0644,
4806 			.proc_handler	= proc_dointvec,
4807 		},
4808 		{
4809 			.procname	= "temp_valid_lft",
4810 			.data		= &ipv6_devconf.temp_valid_lft,
4811 			.maxlen		= sizeof(int),
4812 			.mode		= 0644,
4813 			.proc_handler	= proc_dointvec,
4814 		},
4815 		{
4816 			.procname	= "temp_prefered_lft",
4817 			.data		= &ipv6_devconf.temp_prefered_lft,
4818 			.maxlen		= sizeof(int),
4819 			.mode		= 0644,
4820 			.proc_handler	= proc_dointvec,
4821 		},
4822 		{
4823 			.procname	= "regen_max_retry",
4824 			.data		= &ipv6_devconf.regen_max_retry,
4825 			.maxlen		= sizeof(int),
4826 			.mode		= 0644,
4827 			.proc_handler	= proc_dointvec,
4828 		},
4829 		{
4830 			.procname	= "max_desync_factor",
4831 			.data		= &ipv6_devconf.max_desync_factor,
4832 			.maxlen		= sizeof(int),
4833 			.mode		= 0644,
4834 			.proc_handler	= proc_dointvec,
4835 		},
4836 		{
4837 			.procname	= "max_addresses",
4838 			.data		= &ipv6_devconf.max_addresses,
4839 			.maxlen		= sizeof(int),
4840 			.mode		= 0644,
4841 			.proc_handler	= proc_dointvec,
4842 		},
4843 		{
4844 			.procname	= "accept_ra_defrtr",
4845 			.data		= &ipv6_devconf.accept_ra_defrtr,
4846 			.maxlen		= sizeof(int),
4847 			.mode		= 0644,
4848 			.proc_handler	= proc_dointvec,
4849 		},
4850 		{
4851 			.procname	= "accept_ra_pinfo",
4852 			.data		= &ipv6_devconf.accept_ra_pinfo,
4853 			.maxlen		= sizeof(int),
4854 			.mode		= 0644,
4855 			.proc_handler	= proc_dointvec,
4856 		},
4857 #ifdef CONFIG_IPV6_ROUTER_PREF
4858 		{
4859 			.procname	= "accept_ra_rtr_pref",
4860 			.data		= &ipv6_devconf.accept_ra_rtr_pref,
4861 			.maxlen		= sizeof(int),
4862 			.mode		= 0644,
4863 			.proc_handler	= proc_dointvec,
4864 		},
4865 		{
4866 			.procname	= "router_probe_interval",
4867 			.data		= &ipv6_devconf.rtr_probe_interval,
4868 			.maxlen		= sizeof(int),
4869 			.mode		= 0644,
4870 			.proc_handler	= proc_dointvec_jiffies,
4871 		},
4872 #ifdef CONFIG_IPV6_ROUTE_INFO
4873 		{
4874 			.procname	= "accept_ra_rt_info_max_plen",
4875 			.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
4876 			.maxlen		= sizeof(int),
4877 			.mode		= 0644,
4878 			.proc_handler	= proc_dointvec,
4879 		},
4880 #endif
4881 #endif
4882 		{
4883 			.procname	= "proxy_ndp",
4884 			.data		= &ipv6_devconf.proxy_ndp,
4885 			.maxlen		= sizeof(int),
4886 			.mode		= 0644,
4887 			.proc_handler	= proc_dointvec,
4888 		},
4889 		{
4890 			.procname	= "accept_source_route",
4891 			.data		= &ipv6_devconf.accept_source_route,
4892 			.maxlen		= sizeof(int),
4893 			.mode		= 0644,
4894 			.proc_handler	= proc_dointvec,
4895 		},
4896 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
4897 		{
4898 			.procname       = "optimistic_dad",
4899 			.data           = &ipv6_devconf.optimistic_dad,
4900 			.maxlen         = sizeof(int),
4901 			.mode           = 0644,
4902 			.proc_handler   = proc_dointvec,
4903 
4904 		},
4905 #endif
4906 #ifdef CONFIG_IPV6_MROUTE
4907 		{
4908 			.procname	= "mc_forwarding",
4909 			.data		= &ipv6_devconf.mc_forwarding,
4910 			.maxlen		= sizeof(int),
4911 			.mode		= 0444,
4912 			.proc_handler	= proc_dointvec,
4913 		},
4914 #endif
4915 		{
4916 			.procname	= "disable_ipv6",
4917 			.data		= &ipv6_devconf.disable_ipv6,
4918 			.maxlen		= sizeof(int),
4919 			.mode		= 0644,
4920 			.proc_handler	= addrconf_sysctl_disable,
4921 		},
4922 		{
4923 			.procname	= "accept_dad",
4924 			.data		= &ipv6_devconf.accept_dad,
4925 			.maxlen		= sizeof(int),
4926 			.mode		= 0644,
4927 			.proc_handler	= proc_dointvec,
4928 		},
4929 		{
4930 			.procname       = "force_tllao",
4931 			.data           = &ipv6_devconf.force_tllao,
4932 			.maxlen         = sizeof(int),
4933 			.mode           = 0644,
4934 			.proc_handler   = proc_dointvec
4935 		},
4936 		{
4937 			.procname       = "ndisc_notify",
4938 			.data           = &ipv6_devconf.ndisc_notify,
4939 			.maxlen         = sizeof(int),
4940 			.mode           = 0644,
4941 			.proc_handler   = proc_dointvec
4942 		},
4943 		{
4944 			.procname	= "suppress_frag_ndisc",
4945 			.data		= &ipv6_devconf.suppress_frag_ndisc,
4946 			.maxlen		= sizeof(int),
4947 			.mode		= 0644,
4948 			.proc_handler	= proc_dointvec
4949 		},
4950 		{
4951 			/* sentinel */
4952 		}
4953 	},
4954 };
4955 
4956 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
4957 		struct inet6_dev *idev, struct ipv6_devconf *p)
4958 {
4959 	int i;
4960 	struct addrconf_sysctl_table *t;
4961 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
4962 
4963 	t = kmemdup(&addrconf_sysctl, sizeof(*t), GFP_KERNEL);
4964 	if (t == NULL)
4965 		goto out;
4966 
4967 	for (i = 0; t->addrconf_vars[i].data; i++) {
4968 		t->addrconf_vars[i].data += (char *)p - (char *)&ipv6_devconf;
4969 		t->addrconf_vars[i].extra1 = idev; /* embedded; no ref */
4970 		t->addrconf_vars[i].extra2 = net;
4971 	}
4972 
4973 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
4974 
4975 	t->sysctl_header = register_net_sysctl(net, path, t->addrconf_vars);
4976 	if (t->sysctl_header == NULL)
4977 		goto free;
4978 
4979 	p->sysctl = t;
4980 	return 0;
4981 
4982 free:
4983 	kfree(t);
4984 out:
4985 	return -ENOBUFS;
4986 }
4987 
4988 static void __addrconf_sysctl_unregister(struct ipv6_devconf *p)
4989 {
4990 	struct addrconf_sysctl_table *t;
4991 
4992 	if (p->sysctl == NULL)
4993 		return;
4994 
4995 	t = p->sysctl;
4996 	p->sysctl = NULL;
4997 	unregister_net_sysctl_table(t->sysctl_header);
4998 	kfree(t);
4999 }
5000 
5001 static void addrconf_sysctl_register(struct inet6_dev *idev)
5002 {
5003 	neigh_sysctl_register(idev->dev, idev->nd_parms, "ipv6",
5004 			      &ndisc_ifinfo_sysctl_change);
5005 	__addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
5006 					idev, &idev->cnf);
5007 }
5008 
5009 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
5010 {
5011 	__addrconf_sysctl_unregister(&idev->cnf);
5012 	neigh_sysctl_unregister(idev->nd_parms);
5013 }
5014 
5015 
5016 #endif
5017 
5018 static int __net_init addrconf_init_net(struct net *net)
5019 {
5020 	int err = -ENOMEM;
5021 	struct ipv6_devconf *all, *dflt;
5022 
5023 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
5024 	if (all == NULL)
5025 		goto err_alloc_all;
5026 
5027 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
5028 	if (dflt == NULL)
5029 		goto err_alloc_dflt;
5030 
5031 	/* these will be inherited by all namespaces */
5032 	dflt->autoconf = ipv6_defaults.autoconf;
5033 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
5034 
5035 	net->ipv6.devconf_all = all;
5036 	net->ipv6.devconf_dflt = dflt;
5037 
5038 #ifdef CONFIG_SYSCTL
5039 	err = __addrconf_sysctl_register(net, "all", NULL, all);
5040 	if (err < 0)
5041 		goto err_reg_all;
5042 
5043 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
5044 	if (err < 0)
5045 		goto err_reg_dflt;
5046 #endif
5047 	return 0;
5048 
5049 #ifdef CONFIG_SYSCTL
5050 err_reg_dflt:
5051 	__addrconf_sysctl_unregister(all);
5052 err_reg_all:
5053 	kfree(dflt);
5054 #endif
5055 err_alloc_dflt:
5056 	kfree(all);
5057 err_alloc_all:
5058 	return err;
5059 }
5060 
5061 static void __net_exit addrconf_exit_net(struct net *net)
5062 {
5063 #ifdef CONFIG_SYSCTL
5064 	__addrconf_sysctl_unregister(net->ipv6.devconf_dflt);
5065 	__addrconf_sysctl_unregister(net->ipv6.devconf_all);
5066 #endif
5067 	if (!net_eq(net, &init_net)) {
5068 		kfree(net->ipv6.devconf_dflt);
5069 		kfree(net->ipv6.devconf_all);
5070 	}
5071 }
5072 
5073 static struct pernet_operations addrconf_ops = {
5074 	.init = addrconf_init_net,
5075 	.exit = addrconf_exit_net,
5076 };
5077 
5078 static struct rtnl_af_ops inet6_ops = {
5079 	.family		  = AF_INET6,
5080 	.fill_link_af	  = inet6_fill_link_af,
5081 	.get_link_af_size = inet6_get_link_af_size,
5082 	.set_link_af	  = inet6_set_link_af,
5083 };
5084 
5085 /*
5086  *	Init / cleanup code
5087  */
5088 
5089 int __init addrconf_init(void)
5090 {
5091 	int i, err;
5092 
5093 	err = ipv6_addr_label_init();
5094 	if (err < 0) {
5095 		pr_crit("%s: cannot initialize default policy table: %d\n",
5096 			__func__, err);
5097 		goto out;
5098 	}
5099 
5100 	err = register_pernet_subsys(&addrconf_ops);
5101 	if (err < 0)
5102 		goto out_addrlabel;
5103 
5104 	/* The addrconf netdev notifier requires that loopback_dev
5105 	 * has it's ipv6 private information allocated and setup
5106 	 * before it can bring up and give link-local addresses
5107 	 * to other devices which are up.
5108 	 *
5109 	 * Unfortunately, loopback_dev is not necessarily the first
5110 	 * entry in the global dev_base list of net devices.  In fact,
5111 	 * it is likely to be the very last entry on that list.
5112 	 * So this causes the notifier registry below to try and
5113 	 * give link-local addresses to all devices besides loopback_dev
5114 	 * first, then loopback_dev, which cases all the non-loopback_dev
5115 	 * devices to fail to get a link-local address.
5116 	 *
5117 	 * So, as a temporary fix, allocate the ipv6 structure for
5118 	 * loopback_dev first by hand.
5119 	 * Longer term, all of the dependencies ipv6 has upon the loopback
5120 	 * device and it being up should be removed.
5121 	 */
5122 	rtnl_lock();
5123 	if (!ipv6_add_dev(init_net.loopback_dev))
5124 		err = -ENOMEM;
5125 	rtnl_unlock();
5126 	if (err)
5127 		goto errlo;
5128 
5129 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
5130 		INIT_HLIST_HEAD(&inet6_addr_lst[i]);
5131 
5132 	register_netdevice_notifier(&ipv6_dev_notf);
5133 
5134 	addrconf_verify(0);
5135 
5136 	err = rtnl_af_register(&inet6_ops);
5137 	if (err < 0)
5138 		goto errout_af;
5139 
5140 	err = __rtnl_register(PF_INET6, RTM_GETLINK, NULL, inet6_dump_ifinfo,
5141 			      NULL);
5142 	if (err < 0)
5143 		goto errout;
5144 
5145 	/* Only the first call to __rtnl_register can fail */
5146 	__rtnl_register(PF_INET6, RTM_NEWADDR, inet6_rtm_newaddr, NULL, NULL);
5147 	__rtnl_register(PF_INET6, RTM_DELADDR, inet6_rtm_deladdr, NULL, NULL);
5148 	__rtnl_register(PF_INET6, RTM_GETADDR, inet6_rtm_getaddr,
5149 			inet6_dump_ifaddr, NULL);
5150 	__rtnl_register(PF_INET6, RTM_GETMULTICAST, NULL,
5151 			inet6_dump_ifmcaddr, NULL);
5152 	__rtnl_register(PF_INET6, RTM_GETANYCAST, NULL,
5153 			inet6_dump_ifacaddr, NULL);
5154 	__rtnl_register(PF_INET6, RTM_GETNETCONF, inet6_netconf_get_devconf,
5155 			inet6_netconf_dump_devconf, NULL);
5156 
5157 	ipv6_addr_label_rtnl_register();
5158 
5159 	return 0;
5160 errout:
5161 	rtnl_af_unregister(&inet6_ops);
5162 errout_af:
5163 	unregister_netdevice_notifier(&ipv6_dev_notf);
5164 errlo:
5165 	unregister_pernet_subsys(&addrconf_ops);
5166 out_addrlabel:
5167 	ipv6_addr_label_cleanup();
5168 out:
5169 	return err;
5170 }
5171 
5172 void addrconf_cleanup(void)
5173 {
5174 	struct net_device *dev;
5175 	int i;
5176 
5177 	unregister_netdevice_notifier(&ipv6_dev_notf);
5178 	unregister_pernet_subsys(&addrconf_ops);
5179 	ipv6_addr_label_cleanup();
5180 
5181 	rtnl_lock();
5182 
5183 	__rtnl_af_unregister(&inet6_ops);
5184 
5185 	/* clean dev list */
5186 	for_each_netdev(&init_net, dev) {
5187 		if (__in6_dev_get(dev) == NULL)
5188 			continue;
5189 		addrconf_ifdown(dev, 1);
5190 	}
5191 	addrconf_ifdown(init_net.loopback_dev, 2);
5192 
5193 	/*
5194 	 *	Check hash table.
5195 	 */
5196 	spin_lock_bh(&addrconf_hash_lock);
5197 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
5198 		WARN_ON(!hlist_empty(&inet6_addr_lst[i]));
5199 	spin_unlock_bh(&addrconf_hash_lock);
5200 
5201 	del_timer(&addr_chk_timer);
5202 	rtnl_unlock();
5203 }
5204