xref: /linux/net/ipv6/addrconf.c (revision c75c5ab575af7db707689cdbb5a5c458e9a034bb)
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/ipv6.h>
74 #include <net/protocol.h>
75 #include <net/ndisc.h>
76 #include <net/ip6_route.h>
77 #include <net/addrconf.h>
78 #include <net/tcp.h>
79 #include <net/ip.h>
80 #include <net/netlink.h>
81 #include <net/pkt_sched.h>
82 #include <linux/if_tunnel.h>
83 #include <linux/rtnetlink.h>
84 #include <linux/netconf.h>
85 
86 #ifdef CONFIG_IPV6_PRIVACY
87 #include <linux/random.h>
88 #endif
89 
90 #include <linux/uaccess.h>
91 #include <asm/unaligned.h>
92 
93 #include <linux/proc_fs.h>
94 #include <linux/seq_file.h>
95 #include <linux/export.h>
96 
97 /* Set to 3 to get tracing... */
98 #define ACONF_DEBUG 2
99 
100 #if ACONF_DEBUG >= 3
101 #define ADBG(x) printk x
102 #else
103 #define ADBG(x)
104 #endif
105 
106 #define	INFINITY_LIFE_TIME	0xFFFFFFFF
107 
108 static inline u32 cstamp_delta(unsigned long cstamp)
109 {
110 	return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
111 }
112 
113 #ifdef CONFIG_SYSCTL
114 static void addrconf_sysctl_register(struct inet6_dev *idev);
115 static void addrconf_sysctl_unregister(struct inet6_dev *idev);
116 #else
117 static inline void addrconf_sysctl_register(struct inet6_dev *idev)
118 {
119 }
120 
121 static inline void addrconf_sysctl_unregister(struct inet6_dev *idev)
122 {
123 }
124 #endif
125 
126 #ifdef CONFIG_IPV6_PRIVACY
127 static void __ipv6_regen_rndid(struct inet6_dev *idev);
128 static void __ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr);
129 static void ipv6_regen_rndid(unsigned long data);
130 #endif
131 
132 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev);
133 static int ipv6_count_addresses(struct inet6_dev *idev);
134 
135 /*
136  *	Configured unicast address hash table
137  */
138 static struct hlist_head inet6_addr_lst[IN6_ADDR_HSIZE];
139 static DEFINE_SPINLOCK(addrconf_hash_lock);
140 
141 static void addrconf_verify(unsigned long);
142 
143 static DEFINE_TIMER(addr_chk_timer, addrconf_verify, 0, 0);
144 static DEFINE_SPINLOCK(addrconf_verify_lock);
145 
146 static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
147 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
148 
149 static void addrconf_type_change(struct net_device *dev,
150 				 unsigned long event);
151 static int addrconf_ifdown(struct net_device *dev, int how);
152 
153 static struct rt6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
154 						  int plen,
155 						  const struct net_device *dev,
156 						  u32 flags, u32 noflags);
157 
158 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
159 static void addrconf_dad_timer(unsigned long data);
160 static void addrconf_dad_completed(struct inet6_ifaddr *ifp);
161 static void addrconf_dad_run(struct inet6_dev *idev);
162 static void addrconf_rs_timer(unsigned long data);
163 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
164 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
165 
166 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
167 				struct prefix_info *pinfo);
168 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
169 			       struct net_device *dev);
170 
171 static struct ipv6_devconf ipv6_devconf __read_mostly = {
172 	.forwarding		= 0,
173 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
174 	.mtu6			= IPV6_MIN_MTU,
175 	.accept_ra		= 1,
176 	.accept_redirects	= 1,
177 	.autoconf		= 1,
178 	.force_mld_version	= 0,
179 	.dad_transmits		= 1,
180 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
181 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
182 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
183 #ifdef CONFIG_IPV6_PRIVACY
184 	.use_tempaddr 		= 0,
185 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
186 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
187 	.regen_max_retry	= REGEN_MAX_RETRY,
188 	.max_desync_factor	= MAX_DESYNC_FACTOR,
189 #endif
190 	.max_addresses		= IPV6_MAX_ADDRESSES,
191 	.accept_ra_defrtr	= 1,
192 	.accept_ra_pinfo	= 1,
193 #ifdef CONFIG_IPV6_ROUTER_PREF
194 	.accept_ra_rtr_pref	= 1,
195 	.rtr_probe_interval	= 60 * HZ,
196 #ifdef CONFIG_IPV6_ROUTE_INFO
197 	.accept_ra_rt_info_max_plen = 0,
198 #endif
199 #endif
200 	.proxy_ndp		= 0,
201 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
202 	.disable_ipv6		= 0,
203 	.accept_dad		= 1,
204 };
205 
206 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
207 	.forwarding		= 0,
208 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
209 	.mtu6			= IPV6_MIN_MTU,
210 	.accept_ra		= 1,
211 	.accept_redirects	= 1,
212 	.autoconf		= 1,
213 	.dad_transmits		= 1,
214 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
215 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
216 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
217 #ifdef CONFIG_IPV6_PRIVACY
218 	.use_tempaddr		= 0,
219 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
220 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
221 	.regen_max_retry	= REGEN_MAX_RETRY,
222 	.max_desync_factor	= MAX_DESYNC_FACTOR,
223 #endif
224 	.max_addresses		= IPV6_MAX_ADDRESSES,
225 	.accept_ra_defrtr	= 1,
226 	.accept_ra_pinfo	= 1,
227 #ifdef CONFIG_IPV6_ROUTER_PREF
228 	.accept_ra_rtr_pref	= 1,
229 	.rtr_probe_interval	= 60 * HZ,
230 #ifdef CONFIG_IPV6_ROUTE_INFO
231 	.accept_ra_rt_info_max_plen = 0,
232 #endif
233 #endif
234 	.proxy_ndp		= 0,
235 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
236 	.disable_ipv6		= 0,
237 	.accept_dad		= 1,
238 };
239 
240 /* IPv6 Wildcard Address and Loopback Address defined by RFC2553 */
241 const struct in6_addr in6addr_any = IN6ADDR_ANY_INIT;
242 const struct in6_addr in6addr_loopback = IN6ADDR_LOOPBACK_INIT;
243 const struct in6_addr in6addr_linklocal_allnodes = IN6ADDR_LINKLOCAL_ALLNODES_INIT;
244 const struct in6_addr in6addr_linklocal_allrouters = IN6ADDR_LINKLOCAL_ALLROUTERS_INIT;
245 const struct in6_addr in6addr_interfacelocal_allnodes = IN6ADDR_INTERFACELOCAL_ALLNODES_INIT;
246 const struct in6_addr in6addr_interfacelocal_allrouters = IN6ADDR_INTERFACELOCAL_ALLROUTERS_INIT;
247 const struct in6_addr in6addr_sitelocal_allrouters = IN6ADDR_SITELOCAL_ALLROUTERS_INIT;
248 
249 /* Check if a valid qdisc is available */
250 static inline bool addrconf_qdisc_ok(const struct net_device *dev)
251 {
252 	return !qdisc_tx_is_noop(dev);
253 }
254 
255 static void addrconf_del_timer(struct inet6_ifaddr *ifp)
256 {
257 	if (del_timer(&ifp->timer))
258 		__in6_ifa_put(ifp);
259 }
260 
261 enum addrconf_timer_t {
262 	AC_NONE,
263 	AC_DAD,
264 	AC_RS,
265 };
266 
267 static void addrconf_mod_timer(struct inet6_ifaddr *ifp,
268 			       enum addrconf_timer_t what,
269 			       unsigned long when)
270 {
271 	if (!del_timer(&ifp->timer))
272 		in6_ifa_hold(ifp);
273 
274 	switch (what) {
275 	case AC_DAD:
276 		ifp->timer.function = addrconf_dad_timer;
277 		break;
278 	case AC_RS:
279 		ifp->timer.function = addrconf_rs_timer;
280 		break;
281 	default:
282 		break;
283 	}
284 	ifp->timer.expires = jiffies + when;
285 	add_timer(&ifp->timer);
286 }
287 
288 static int snmp6_alloc_dev(struct inet6_dev *idev)
289 {
290 	if (snmp_mib_init((void __percpu **)idev->stats.ipv6,
291 			  sizeof(struct ipstats_mib),
292 			  __alignof__(struct ipstats_mib)) < 0)
293 		goto err_ip;
294 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
295 					GFP_KERNEL);
296 	if (!idev->stats.icmpv6dev)
297 		goto err_icmp;
298 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
299 					   GFP_KERNEL);
300 	if (!idev->stats.icmpv6msgdev)
301 		goto err_icmpmsg;
302 
303 	return 0;
304 
305 err_icmpmsg:
306 	kfree(idev->stats.icmpv6dev);
307 err_icmp:
308 	snmp_mib_free((void __percpu **)idev->stats.ipv6);
309 err_ip:
310 	return -ENOMEM;
311 }
312 
313 static void snmp6_free_dev(struct inet6_dev *idev)
314 {
315 	kfree(idev->stats.icmpv6msgdev);
316 	kfree(idev->stats.icmpv6dev);
317 	snmp_mib_free((void __percpu **)idev->stats.ipv6);
318 }
319 
320 /* Nobody refers to this device, we may destroy it. */
321 
322 void in6_dev_finish_destroy(struct inet6_dev *idev)
323 {
324 	struct net_device *dev = idev->dev;
325 
326 	WARN_ON(!list_empty(&idev->addr_list));
327 	WARN_ON(idev->mc_list != NULL);
328 
329 #ifdef NET_REFCNT_DEBUG
330 	pr_debug("%s: %s\n", __func__, dev ? dev->name : "NIL");
331 #endif
332 	dev_put(dev);
333 	if (!idev->dead) {
334 		pr_warn("Freeing alive inet6 device %p\n", idev);
335 		return;
336 	}
337 	snmp6_free_dev(idev);
338 	kfree_rcu(idev, rcu);
339 }
340 EXPORT_SYMBOL(in6_dev_finish_destroy);
341 
342 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
343 {
344 	struct inet6_dev *ndev;
345 
346 	ASSERT_RTNL();
347 
348 	if (dev->mtu < IPV6_MIN_MTU)
349 		return NULL;
350 
351 	ndev = kzalloc(sizeof(struct inet6_dev), GFP_KERNEL);
352 
353 	if (ndev == NULL)
354 		return NULL;
355 
356 	rwlock_init(&ndev->lock);
357 	ndev->dev = dev;
358 	INIT_LIST_HEAD(&ndev->addr_list);
359 
360 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
361 	ndev->cnf.mtu6 = dev->mtu;
362 	ndev->cnf.sysctl = NULL;
363 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
364 	if (ndev->nd_parms == NULL) {
365 		kfree(ndev);
366 		return NULL;
367 	}
368 	if (ndev->cnf.forwarding)
369 		dev_disable_lro(dev);
370 	/* We refer to the device */
371 	dev_hold(dev);
372 
373 	if (snmp6_alloc_dev(ndev) < 0) {
374 		ADBG((KERN_WARNING
375 			"%s: cannot allocate memory for statistics; dev=%s.\n",
376 			__func__, dev->name));
377 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
378 		dev_put(dev);
379 		kfree(ndev);
380 		return NULL;
381 	}
382 
383 	if (snmp6_register_dev(ndev) < 0) {
384 		ADBG((KERN_WARNING
385 			"%s: cannot create /proc/net/dev_snmp6/%s\n",
386 			__func__, dev->name));
387 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
388 		ndev->dead = 1;
389 		in6_dev_finish_destroy(ndev);
390 		return NULL;
391 	}
392 
393 	/* One reference from device.  We must do this before
394 	 * we invoke __ipv6_regen_rndid().
395 	 */
396 	in6_dev_hold(ndev);
397 
398 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
399 		ndev->cnf.accept_dad = -1;
400 
401 #if IS_ENABLED(CONFIG_IPV6_SIT)
402 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
403 		pr_info("%s: Disabled Multicast RS\n", dev->name);
404 		ndev->cnf.rtr_solicits = 0;
405 	}
406 #endif
407 
408 #ifdef CONFIG_IPV6_PRIVACY
409 	INIT_LIST_HEAD(&ndev->tempaddr_list);
410 	setup_timer(&ndev->regen_timer, ipv6_regen_rndid, (unsigned long)ndev);
411 	if ((dev->flags&IFF_LOOPBACK) ||
412 	    dev->type == ARPHRD_TUNNEL ||
413 	    dev->type == ARPHRD_TUNNEL6 ||
414 	    dev->type == ARPHRD_SIT ||
415 	    dev->type == ARPHRD_NONE) {
416 		ndev->cnf.use_tempaddr = -1;
417 	} else {
418 		in6_dev_hold(ndev);
419 		ipv6_regen_rndid((unsigned long) ndev);
420 	}
421 #endif
422 
423 	if (netif_running(dev) && addrconf_qdisc_ok(dev))
424 		ndev->if_flags |= IF_READY;
425 
426 	ipv6_mc_init_dev(ndev);
427 	ndev->tstamp = jiffies;
428 	addrconf_sysctl_register(ndev);
429 	/* protected by rtnl_lock */
430 	rcu_assign_pointer(dev->ip6_ptr, ndev);
431 
432 	/* Join interface-local all-node multicast group */
433 	ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes);
434 
435 	/* Join all-node multicast group */
436 	ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
437 
438 	/* Join all-router multicast group if forwarding is set */
439 	if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
440 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
441 
442 	return ndev;
443 }
444 
445 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
446 {
447 	struct inet6_dev *idev;
448 
449 	ASSERT_RTNL();
450 
451 	idev = __in6_dev_get(dev);
452 	if (!idev) {
453 		idev = ipv6_add_dev(dev);
454 		if (!idev)
455 			return NULL;
456 	}
457 
458 	if (dev->flags&IFF_UP)
459 		ipv6_mc_up(idev);
460 	return idev;
461 }
462 
463 static int inet6_netconf_msgsize_devconf(int type)
464 {
465 	int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
466 		    + nla_total_size(4);	/* NETCONFA_IFINDEX */
467 
468 	/* type -1 is used for ALL */
469 	if (type == -1 || type == NETCONFA_FORWARDING)
470 		size += nla_total_size(4);
471 #ifdef CONFIG_IPV6_MROUTE
472 	if (type == -1 || type == NETCONFA_MC_FORWARDING)
473 		size += nla_total_size(4);
474 #endif
475 
476 	return size;
477 }
478 
479 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
480 				      struct ipv6_devconf *devconf, u32 portid,
481 				      u32 seq, int event, unsigned int flags,
482 				      int type)
483 {
484 	struct nlmsghdr  *nlh;
485 	struct netconfmsg *ncm;
486 
487 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
488 			flags);
489 	if (nlh == NULL)
490 		return -EMSGSIZE;
491 
492 	ncm = nlmsg_data(nlh);
493 	ncm->ncm_family = AF_INET6;
494 
495 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
496 		goto nla_put_failure;
497 
498 	/* type -1 is used for ALL */
499 	if ((type == -1 || type == NETCONFA_FORWARDING) &&
500 	    nla_put_s32(skb, NETCONFA_FORWARDING, devconf->forwarding) < 0)
501 		goto nla_put_failure;
502 #ifdef CONFIG_IPV6_MROUTE
503 	if ((type == -1 || type == NETCONFA_MC_FORWARDING) &&
504 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
505 			devconf->mc_forwarding) < 0)
506 		goto nla_put_failure;
507 #endif
508 	return nlmsg_end(skb, nlh);
509 
510 nla_put_failure:
511 	nlmsg_cancel(skb, nlh);
512 	return -EMSGSIZE;
513 }
514 
515 void inet6_netconf_notify_devconf(struct net *net, int type, int ifindex,
516 				  struct ipv6_devconf *devconf)
517 {
518 	struct sk_buff *skb;
519 	int err = -ENOBUFS;
520 
521 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_ATOMIC);
522 	if (skb == NULL)
523 		goto errout;
524 
525 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
526 					 RTM_NEWNETCONF, 0, type);
527 	if (err < 0) {
528 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
529 		WARN_ON(err == -EMSGSIZE);
530 		kfree_skb(skb);
531 		goto errout;
532 	}
533 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_ATOMIC);
534 	return;
535 errout:
536 	rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
537 }
538 
539 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
540 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
541 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
542 };
543 
544 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
545 				     struct nlmsghdr *nlh,
546 				     void *arg)
547 {
548 	struct net *net = sock_net(in_skb->sk);
549 	struct nlattr *tb[NETCONFA_MAX+1];
550 	struct netconfmsg *ncm;
551 	struct sk_buff *skb;
552 	struct ipv6_devconf *devconf;
553 	struct inet6_dev *in6_dev;
554 	struct net_device *dev;
555 	int ifindex;
556 	int err;
557 
558 	err = nlmsg_parse(nlh, sizeof(*ncm), tb, NETCONFA_MAX,
559 			  devconf_ipv6_policy);
560 	if (err < 0)
561 		goto errout;
562 
563 	err = EINVAL;
564 	if (!tb[NETCONFA_IFINDEX])
565 		goto errout;
566 
567 	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
568 	switch (ifindex) {
569 	case NETCONFA_IFINDEX_ALL:
570 		devconf = net->ipv6.devconf_all;
571 		break;
572 	case NETCONFA_IFINDEX_DEFAULT:
573 		devconf = net->ipv6.devconf_dflt;
574 		break;
575 	default:
576 		dev = __dev_get_by_index(net, ifindex);
577 		if (dev == NULL)
578 			goto errout;
579 		in6_dev = __in6_dev_get(dev);
580 		if (in6_dev == NULL)
581 			goto errout;
582 		devconf = &in6_dev->cnf;
583 		break;
584 	}
585 
586 	err = -ENOBUFS;
587 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(-1), GFP_ATOMIC);
588 	if (skb == NULL)
589 		goto errout;
590 
591 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
592 					 NETLINK_CB(in_skb).portid,
593 					 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
594 					 -1);
595 	if (err < 0) {
596 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
597 		WARN_ON(err == -EMSGSIZE);
598 		kfree_skb(skb);
599 		goto errout;
600 	}
601 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
602 errout:
603 	return err;
604 }
605 
606 #ifdef CONFIG_SYSCTL
607 static void dev_forward_change(struct inet6_dev *idev)
608 {
609 	struct net_device *dev;
610 	struct inet6_ifaddr *ifa;
611 
612 	if (!idev)
613 		return;
614 	dev = idev->dev;
615 	if (idev->cnf.forwarding)
616 		dev_disable_lro(dev);
617 	if (dev->flags & IFF_MULTICAST) {
618 		if (idev->cnf.forwarding) {
619 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
620 			ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
621 			ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters);
622 		} else {
623 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
624 			ipv6_dev_mc_dec(dev, &in6addr_interfacelocal_allrouters);
625 			ipv6_dev_mc_dec(dev, &in6addr_sitelocal_allrouters);
626 		}
627 	}
628 
629 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
630 		if (ifa->flags&IFA_F_TENTATIVE)
631 			continue;
632 		if (idev->cnf.forwarding)
633 			addrconf_join_anycast(ifa);
634 		else
635 			addrconf_leave_anycast(ifa);
636 	}
637 	inet6_netconf_notify_devconf(dev_net(dev), NETCONFA_FORWARDING,
638 				     dev->ifindex, &idev->cnf);
639 }
640 
641 
642 static void addrconf_forward_change(struct net *net, __s32 newf)
643 {
644 	struct net_device *dev;
645 	struct inet6_dev *idev;
646 
647 	for_each_netdev(net, dev) {
648 		idev = __in6_dev_get(dev);
649 		if (idev) {
650 			int changed = (!idev->cnf.forwarding) ^ (!newf);
651 			idev->cnf.forwarding = newf;
652 			if (changed)
653 				dev_forward_change(idev);
654 		}
655 	}
656 }
657 
658 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int newf)
659 {
660 	struct net *net;
661 	int old;
662 
663 	if (!rtnl_trylock())
664 		return restart_syscall();
665 
666 	net = (struct net *)table->extra2;
667 	old = *p;
668 	*p = newf;
669 
670 	if (p == &net->ipv6.devconf_dflt->forwarding) {
671 		if ((!newf) ^ (!old))
672 			inet6_netconf_notify_devconf(net, NETCONFA_FORWARDING,
673 						     NETCONFA_IFINDEX_DEFAULT,
674 						     net->ipv6.devconf_dflt);
675 		rtnl_unlock();
676 		return 0;
677 	}
678 
679 	if (p == &net->ipv6.devconf_all->forwarding) {
680 		net->ipv6.devconf_dflt->forwarding = newf;
681 		addrconf_forward_change(net, newf);
682 		if ((!newf) ^ (!old))
683 			inet6_netconf_notify_devconf(net, NETCONFA_FORWARDING,
684 						     NETCONFA_IFINDEX_ALL,
685 						     net->ipv6.devconf_all);
686 	} else if ((!newf) ^ (!old))
687 		dev_forward_change((struct inet6_dev *)table->extra1);
688 	rtnl_unlock();
689 
690 	if (newf)
691 		rt6_purge_dflt_routers(net);
692 	return 1;
693 }
694 #endif
695 
696 /* Nobody refers to this ifaddr, destroy it */
697 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
698 {
699 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
700 
701 #ifdef NET_REFCNT_DEBUG
702 	pr_debug("%s\n", __func__);
703 #endif
704 
705 	in6_dev_put(ifp->idev);
706 
707 	if (del_timer(&ifp->timer))
708 		pr_notice("Timer is still running, when freeing ifa=%p\n", ifp);
709 
710 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
711 		pr_warn("Freeing alive inet6 address %p\n", ifp);
712 		return;
713 	}
714 	ip6_rt_put(ifp->rt);
715 
716 	kfree_rcu(ifp, rcu);
717 }
718 
719 static void
720 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
721 {
722 	struct list_head *p;
723 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
724 
725 	/*
726 	 * Each device address list is sorted in order of scope -
727 	 * global before linklocal.
728 	 */
729 	list_for_each(p, &idev->addr_list) {
730 		struct inet6_ifaddr *ifa
731 			= list_entry(p, struct inet6_ifaddr, if_list);
732 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
733 			break;
734 	}
735 
736 	list_add_tail(&ifp->if_list, p);
737 }
738 
739 static u32 inet6_addr_hash(const struct in6_addr *addr)
740 {
741 	return hash_32(ipv6_addr_hash(addr), IN6_ADDR_HSIZE_SHIFT);
742 }
743 
744 /* On success it returns ifp with increased reference count */
745 
746 static struct inet6_ifaddr *
747 ipv6_add_addr(struct inet6_dev *idev, const struct in6_addr *addr, int pfxlen,
748 	      int scope, u32 flags)
749 {
750 	struct inet6_ifaddr *ifa = NULL;
751 	struct rt6_info *rt;
752 	unsigned int hash;
753 	int err = 0;
754 	int addr_type = ipv6_addr_type(addr);
755 
756 	if (addr_type == IPV6_ADDR_ANY ||
757 	    addr_type & IPV6_ADDR_MULTICAST ||
758 	    (!(idev->dev->flags & IFF_LOOPBACK) &&
759 	     addr_type & IPV6_ADDR_LOOPBACK))
760 		return ERR_PTR(-EADDRNOTAVAIL);
761 
762 	rcu_read_lock_bh();
763 	if (idev->dead) {
764 		err = -ENODEV;			/*XXX*/
765 		goto out2;
766 	}
767 
768 	if (idev->cnf.disable_ipv6) {
769 		err = -EACCES;
770 		goto out2;
771 	}
772 
773 	spin_lock(&addrconf_hash_lock);
774 
775 	/* Ignore adding duplicate addresses on an interface */
776 	if (ipv6_chk_same_addr(dev_net(idev->dev), addr, idev->dev)) {
777 		ADBG(("ipv6_add_addr: already assigned\n"));
778 		err = -EEXIST;
779 		goto out;
780 	}
781 
782 	ifa = kzalloc(sizeof(struct inet6_ifaddr), GFP_ATOMIC);
783 
784 	if (ifa == NULL) {
785 		ADBG(("ipv6_add_addr: malloc failed\n"));
786 		err = -ENOBUFS;
787 		goto out;
788 	}
789 
790 	rt = addrconf_dst_alloc(idev, addr, false);
791 	if (IS_ERR(rt)) {
792 		err = PTR_ERR(rt);
793 		goto out;
794 	}
795 
796 	ifa->addr = *addr;
797 
798 	spin_lock_init(&ifa->lock);
799 	spin_lock_init(&ifa->state_lock);
800 	init_timer(&ifa->timer);
801 	INIT_HLIST_NODE(&ifa->addr_lst);
802 	ifa->timer.data = (unsigned long) ifa;
803 	ifa->scope = scope;
804 	ifa->prefix_len = pfxlen;
805 	ifa->flags = flags | IFA_F_TENTATIVE;
806 	ifa->cstamp = ifa->tstamp = jiffies;
807 
808 	ifa->rt = rt;
809 
810 	ifa->idev = idev;
811 	in6_dev_hold(idev);
812 	/* For caller */
813 	in6_ifa_hold(ifa);
814 
815 	/* Add to big hash table */
816 	hash = inet6_addr_hash(addr);
817 
818 	hlist_add_head_rcu(&ifa->addr_lst, &inet6_addr_lst[hash]);
819 	spin_unlock(&addrconf_hash_lock);
820 
821 	write_lock(&idev->lock);
822 	/* Add to inet6_dev unicast addr list. */
823 	ipv6_link_dev_addr(idev, ifa);
824 
825 #ifdef CONFIG_IPV6_PRIVACY
826 	if (ifa->flags&IFA_F_TEMPORARY) {
827 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
828 		in6_ifa_hold(ifa);
829 	}
830 #endif
831 
832 	in6_ifa_hold(ifa);
833 	write_unlock(&idev->lock);
834 out2:
835 	rcu_read_unlock_bh();
836 
837 	if (likely(err == 0))
838 		inet6addr_notifier_call_chain(NETDEV_UP, ifa);
839 	else {
840 		kfree(ifa);
841 		ifa = ERR_PTR(err);
842 	}
843 
844 	return ifa;
845 out:
846 	spin_unlock(&addrconf_hash_lock);
847 	goto out2;
848 }
849 
850 /* This function wants to get referenced ifp and releases it before return */
851 
852 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
853 {
854 	struct inet6_ifaddr *ifa, *ifn;
855 	struct inet6_dev *idev = ifp->idev;
856 	int state;
857 	int deleted = 0, onlink = 0;
858 	unsigned long expires = jiffies;
859 
860 	spin_lock_bh(&ifp->state_lock);
861 	state = ifp->state;
862 	ifp->state = INET6_IFADDR_STATE_DEAD;
863 	spin_unlock_bh(&ifp->state_lock);
864 
865 	if (state == INET6_IFADDR_STATE_DEAD)
866 		goto out;
867 
868 	spin_lock_bh(&addrconf_hash_lock);
869 	hlist_del_init_rcu(&ifp->addr_lst);
870 	spin_unlock_bh(&addrconf_hash_lock);
871 
872 	write_lock_bh(&idev->lock);
873 #ifdef CONFIG_IPV6_PRIVACY
874 	if (ifp->flags&IFA_F_TEMPORARY) {
875 		list_del(&ifp->tmp_list);
876 		if (ifp->ifpub) {
877 			in6_ifa_put(ifp->ifpub);
878 			ifp->ifpub = NULL;
879 		}
880 		__in6_ifa_put(ifp);
881 	}
882 #endif
883 
884 	list_for_each_entry_safe(ifa, ifn, &idev->addr_list, if_list) {
885 		if (ifa == ifp) {
886 			list_del_init(&ifp->if_list);
887 			__in6_ifa_put(ifp);
888 
889 			if (!(ifp->flags & IFA_F_PERMANENT) || onlink > 0)
890 				break;
891 			deleted = 1;
892 			continue;
893 		} else if (ifp->flags & IFA_F_PERMANENT) {
894 			if (ipv6_prefix_equal(&ifa->addr, &ifp->addr,
895 					      ifp->prefix_len)) {
896 				if (ifa->flags & IFA_F_PERMANENT) {
897 					onlink = 1;
898 					if (deleted)
899 						break;
900 				} else {
901 					unsigned long lifetime;
902 
903 					if (!onlink)
904 						onlink = -1;
905 
906 					spin_lock(&ifa->lock);
907 
908 					lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
909 					/*
910 					 * Note: Because this address is
911 					 * not permanent, lifetime <
912 					 * LONG_MAX / HZ here.
913 					 */
914 					if (time_before(expires,
915 							ifa->tstamp + lifetime * HZ))
916 						expires = ifa->tstamp + lifetime * HZ;
917 					spin_unlock(&ifa->lock);
918 				}
919 			}
920 		}
921 	}
922 	write_unlock_bh(&idev->lock);
923 
924 	addrconf_del_timer(ifp);
925 
926 	ipv6_ifa_notify(RTM_DELADDR, ifp);
927 
928 	inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);
929 
930 	/*
931 	 * Purge or update corresponding prefix
932 	 *
933 	 * 1) we don't purge prefix here if address was not permanent.
934 	 *    prefix is managed by its own lifetime.
935 	 * 2) if there're no addresses, delete prefix.
936 	 * 3) if there're still other permanent address(es),
937 	 *    corresponding prefix is still permanent.
938 	 * 4) otherwise, update prefix lifetime to the
939 	 *    longest valid lifetime among the corresponding
940 	 *    addresses on the device.
941 	 *    Note: subsequent RA will update lifetime.
942 	 *
943 	 * --yoshfuji
944 	 */
945 	if ((ifp->flags & IFA_F_PERMANENT) && onlink < 1) {
946 		struct in6_addr prefix;
947 		struct rt6_info *rt;
948 
949 		ipv6_addr_prefix(&prefix, &ifp->addr, ifp->prefix_len);
950 
951 		rt = addrconf_get_prefix_route(&prefix,
952 					       ifp->prefix_len,
953 					       ifp->idev->dev,
954 					       0, RTF_GATEWAY | RTF_DEFAULT);
955 
956 		if (rt) {
957 			if (onlink == 0) {
958 				ip6_del_rt(rt);
959 				rt = NULL;
960 			} else if (!(rt->rt6i_flags & RTF_EXPIRES)) {
961 				rt6_set_expires(rt, expires);
962 			}
963 		}
964 		ip6_rt_put(rt);
965 	}
966 
967 	/* clean up prefsrc entries */
968 	rt6_remove_prefsrc(ifp);
969 out:
970 	in6_ifa_put(ifp);
971 }
972 
973 #ifdef CONFIG_IPV6_PRIVACY
974 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp, struct inet6_ifaddr *ift)
975 {
976 	struct inet6_dev *idev = ifp->idev;
977 	struct in6_addr addr, *tmpaddr;
978 	unsigned long tmp_prefered_lft, tmp_valid_lft, tmp_tstamp, age;
979 	unsigned long regen_advance;
980 	int tmp_plen;
981 	int ret = 0;
982 	int max_addresses;
983 	u32 addr_flags;
984 	unsigned long now = jiffies;
985 
986 	write_lock(&idev->lock);
987 	if (ift) {
988 		spin_lock_bh(&ift->lock);
989 		memcpy(&addr.s6_addr[8], &ift->addr.s6_addr[8], 8);
990 		spin_unlock_bh(&ift->lock);
991 		tmpaddr = &addr;
992 	} else {
993 		tmpaddr = NULL;
994 	}
995 retry:
996 	in6_dev_hold(idev);
997 	if (idev->cnf.use_tempaddr <= 0) {
998 		write_unlock(&idev->lock);
999 		pr_info("%s: use_tempaddr is disabled\n", __func__);
1000 		in6_dev_put(idev);
1001 		ret = -1;
1002 		goto out;
1003 	}
1004 	spin_lock_bh(&ifp->lock);
1005 	if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
1006 		idev->cnf.use_tempaddr = -1;	/*XXX*/
1007 		spin_unlock_bh(&ifp->lock);
1008 		write_unlock(&idev->lock);
1009 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1010 			__func__);
1011 		in6_dev_put(idev);
1012 		ret = -1;
1013 		goto out;
1014 	}
1015 	in6_ifa_hold(ifp);
1016 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1017 	__ipv6_try_regen_rndid(idev, tmpaddr);
1018 	memcpy(&addr.s6_addr[8], idev->rndid, 8);
1019 	age = (now - ifp->tstamp) / HZ;
1020 	tmp_valid_lft = min_t(__u32,
1021 			      ifp->valid_lft,
1022 			      idev->cnf.temp_valid_lft + age);
1023 	tmp_prefered_lft = min_t(__u32,
1024 				 ifp->prefered_lft,
1025 				 idev->cnf.temp_prefered_lft + age -
1026 				 idev->cnf.max_desync_factor);
1027 	tmp_plen = ifp->prefix_len;
1028 	max_addresses = idev->cnf.max_addresses;
1029 	tmp_tstamp = ifp->tstamp;
1030 	spin_unlock_bh(&ifp->lock);
1031 
1032 	regen_advance = idev->cnf.regen_max_retry *
1033 	                idev->cnf.dad_transmits *
1034 	                idev->nd_parms->retrans_time / HZ;
1035 	write_unlock(&idev->lock);
1036 
1037 	/* A temporary address is created only if this calculated Preferred
1038 	 * Lifetime is greater than REGEN_ADVANCE time units.  In particular,
1039 	 * an implementation must not create a temporary address with a zero
1040 	 * Preferred Lifetime.
1041 	 */
1042 	if (tmp_prefered_lft <= regen_advance) {
1043 		in6_ifa_put(ifp);
1044 		in6_dev_put(idev);
1045 		ret = -1;
1046 		goto out;
1047 	}
1048 
1049 	addr_flags = IFA_F_TEMPORARY;
1050 	/* set in addrconf_prefix_rcv() */
1051 	if (ifp->flags & IFA_F_OPTIMISTIC)
1052 		addr_flags |= IFA_F_OPTIMISTIC;
1053 
1054 	ift = !max_addresses ||
1055 	      ipv6_count_addresses(idev) < max_addresses ?
1056 		ipv6_add_addr(idev, &addr, tmp_plen,
1057 			      ipv6_addr_type(&addr)&IPV6_ADDR_SCOPE_MASK,
1058 			      addr_flags) : NULL;
1059 	if (IS_ERR_OR_NULL(ift)) {
1060 		in6_ifa_put(ifp);
1061 		in6_dev_put(idev);
1062 		pr_info("%s: retry temporary address regeneration\n", __func__);
1063 		tmpaddr = &addr;
1064 		write_lock(&idev->lock);
1065 		goto retry;
1066 	}
1067 
1068 	spin_lock_bh(&ift->lock);
1069 	ift->ifpub = ifp;
1070 	ift->valid_lft = tmp_valid_lft;
1071 	ift->prefered_lft = tmp_prefered_lft;
1072 	ift->cstamp = now;
1073 	ift->tstamp = tmp_tstamp;
1074 	spin_unlock_bh(&ift->lock);
1075 
1076 	addrconf_dad_start(ift);
1077 	in6_ifa_put(ift);
1078 	in6_dev_put(idev);
1079 out:
1080 	return ret;
1081 }
1082 #endif
1083 
1084 /*
1085  *	Choose an appropriate source address (RFC3484)
1086  */
1087 enum {
1088 	IPV6_SADDR_RULE_INIT = 0,
1089 	IPV6_SADDR_RULE_LOCAL,
1090 	IPV6_SADDR_RULE_SCOPE,
1091 	IPV6_SADDR_RULE_PREFERRED,
1092 #ifdef CONFIG_IPV6_MIP6
1093 	IPV6_SADDR_RULE_HOA,
1094 #endif
1095 	IPV6_SADDR_RULE_OIF,
1096 	IPV6_SADDR_RULE_LABEL,
1097 #ifdef CONFIG_IPV6_PRIVACY
1098 	IPV6_SADDR_RULE_PRIVACY,
1099 #endif
1100 	IPV6_SADDR_RULE_ORCHID,
1101 	IPV6_SADDR_RULE_PREFIX,
1102 	IPV6_SADDR_RULE_MAX
1103 };
1104 
1105 struct ipv6_saddr_score {
1106 	int			rule;
1107 	int			addr_type;
1108 	struct inet6_ifaddr	*ifa;
1109 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1110 	int			scopedist;
1111 	int			matchlen;
1112 };
1113 
1114 struct ipv6_saddr_dst {
1115 	const struct in6_addr *addr;
1116 	int ifindex;
1117 	int scope;
1118 	int label;
1119 	unsigned int prefs;
1120 };
1121 
1122 static inline int ipv6_saddr_preferred(int type)
1123 {
1124 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1125 		return 1;
1126 	return 0;
1127 }
1128 
1129 static int ipv6_get_saddr_eval(struct net *net,
1130 			       struct ipv6_saddr_score *score,
1131 			       struct ipv6_saddr_dst *dst,
1132 			       int i)
1133 {
1134 	int ret;
1135 
1136 	if (i <= score->rule) {
1137 		switch (i) {
1138 		case IPV6_SADDR_RULE_SCOPE:
1139 			ret = score->scopedist;
1140 			break;
1141 		case IPV6_SADDR_RULE_PREFIX:
1142 			ret = score->matchlen;
1143 			break;
1144 		default:
1145 			ret = !!test_bit(i, score->scorebits);
1146 		}
1147 		goto out;
1148 	}
1149 
1150 	switch (i) {
1151 	case IPV6_SADDR_RULE_INIT:
1152 		/* Rule 0: remember if hiscore is not ready yet */
1153 		ret = !!score->ifa;
1154 		break;
1155 	case IPV6_SADDR_RULE_LOCAL:
1156 		/* Rule 1: Prefer same address */
1157 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1158 		break;
1159 	case IPV6_SADDR_RULE_SCOPE:
1160 		/* Rule 2: Prefer appropriate scope
1161 		 *
1162 		 *      ret
1163 		 *       ^
1164 		 *    -1 |  d 15
1165 		 *    ---+--+-+---> scope
1166 		 *       |
1167 		 *       |             d is scope of the destination.
1168 		 *  B-d  |  \
1169 		 *       |   \      <- smaller scope is better if
1170 		 *  B-15 |    \        if scope is enough for destinaion.
1171 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1172 		 * d-C-1 | /
1173 		 *       |/         <- greater is better
1174 		 *   -C  /             if scope is not enough for destination.
1175 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1176 		 *
1177 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1178 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1179 		 * Assume B = 0 and we get C > 29.
1180 		 */
1181 		ret = __ipv6_addr_src_scope(score->addr_type);
1182 		if (ret >= dst->scope)
1183 			ret = -ret;
1184 		else
1185 			ret -= 128;	/* 30 is enough */
1186 		score->scopedist = ret;
1187 		break;
1188 	case IPV6_SADDR_RULE_PREFERRED:
1189 		/* Rule 3: Avoid deprecated and optimistic addresses */
1190 		ret = ipv6_saddr_preferred(score->addr_type) ||
1191 		      !(score->ifa->flags & (IFA_F_DEPRECATED|IFA_F_OPTIMISTIC));
1192 		break;
1193 #ifdef CONFIG_IPV6_MIP6
1194 	case IPV6_SADDR_RULE_HOA:
1195 	    {
1196 		/* Rule 4: Prefer home address */
1197 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1198 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1199 		break;
1200 	    }
1201 #endif
1202 	case IPV6_SADDR_RULE_OIF:
1203 		/* Rule 5: Prefer outgoing interface */
1204 		ret = (!dst->ifindex ||
1205 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1206 		break;
1207 	case IPV6_SADDR_RULE_LABEL:
1208 		/* Rule 6: Prefer matching label */
1209 		ret = ipv6_addr_label(net,
1210 				      &score->ifa->addr, score->addr_type,
1211 				      score->ifa->idev->dev->ifindex) == dst->label;
1212 		break;
1213 #ifdef CONFIG_IPV6_PRIVACY
1214 	case IPV6_SADDR_RULE_PRIVACY:
1215 	    {
1216 		/* Rule 7: Prefer public address
1217 		 * Note: prefer temporary address if use_tempaddr >= 2
1218 		 */
1219 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1220 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1221 				score->ifa->idev->cnf.use_tempaddr >= 2;
1222 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1223 		break;
1224 	    }
1225 #endif
1226 	case IPV6_SADDR_RULE_ORCHID:
1227 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1228 		 *	    non-ORCHID vs non-ORCHID
1229 		 */
1230 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1231 			ipv6_addr_orchid(dst->addr));
1232 		break;
1233 	case IPV6_SADDR_RULE_PREFIX:
1234 		/* Rule 8: Use longest matching prefix */
1235 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1236 		if (ret > score->ifa->prefix_len)
1237 			ret = score->ifa->prefix_len;
1238 		score->matchlen = ret;
1239 		break;
1240 	default:
1241 		ret = 0;
1242 	}
1243 
1244 	if (ret)
1245 		__set_bit(i, score->scorebits);
1246 	score->rule = i;
1247 out:
1248 	return ret;
1249 }
1250 
1251 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1252 		       const struct in6_addr *daddr, unsigned int prefs,
1253 		       struct in6_addr *saddr)
1254 {
1255 	struct ipv6_saddr_score scores[2],
1256 				*score = &scores[0], *hiscore = &scores[1];
1257 	struct ipv6_saddr_dst dst;
1258 	struct net_device *dev;
1259 	int dst_type;
1260 
1261 	dst_type = __ipv6_addr_type(daddr);
1262 	dst.addr = daddr;
1263 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1264 	dst.scope = __ipv6_addr_src_scope(dst_type);
1265 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1266 	dst.prefs = prefs;
1267 
1268 	hiscore->rule = -1;
1269 	hiscore->ifa = NULL;
1270 
1271 	rcu_read_lock();
1272 
1273 	for_each_netdev_rcu(net, dev) {
1274 		struct inet6_dev *idev;
1275 
1276 		/* Candidate Source Address (section 4)
1277 		 *  - multicast and link-local destination address,
1278 		 *    the set of candidate source address MUST only
1279 		 *    include addresses assigned to interfaces
1280 		 *    belonging to the same link as the outgoing
1281 		 *    interface.
1282 		 * (- For site-local destination addresses, the
1283 		 *    set of candidate source addresses MUST only
1284 		 *    include addresses assigned to interfaces
1285 		 *    belonging to the same site as the outgoing
1286 		 *    interface.)
1287 		 */
1288 		if (((dst_type & IPV6_ADDR_MULTICAST) ||
1289 		     dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL) &&
1290 		    dst.ifindex && dev->ifindex != dst.ifindex)
1291 			continue;
1292 
1293 		idev = __in6_dev_get(dev);
1294 		if (!idev)
1295 			continue;
1296 
1297 		read_lock_bh(&idev->lock);
1298 		list_for_each_entry(score->ifa, &idev->addr_list, if_list) {
1299 			int i;
1300 
1301 			/*
1302 			 * - Tentative Address (RFC2462 section 5.4)
1303 			 *  - A tentative address is not considered
1304 			 *    "assigned to an interface" in the traditional
1305 			 *    sense, unless it is also flagged as optimistic.
1306 			 * - Candidate Source Address (section 4)
1307 			 *  - In any case, anycast addresses, multicast
1308 			 *    addresses, and the unspecified address MUST
1309 			 *    NOT be included in a candidate set.
1310 			 */
1311 			if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1312 			    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1313 				continue;
1314 
1315 			score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1316 
1317 			if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1318 				     score->addr_type & IPV6_ADDR_MULTICAST)) {
1319 				LIMIT_NETDEBUG(KERN_DEBUG
1320 					       "ADDRCONF: unspecified / multicast address "
1321 					       "assigned as unicast address on %s",
1322 					       dev->name);
1323 				continue;
1324 			}
1325 
1326 			score->rule = -1;
1327 			bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1328 
1329 			for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1330 				int minihiscore, miniscore;
1331 
1332 				minihiscore = ipv6_get_saddr_eval(net, hiscore, &dst, i);
1333 				miniscore = ipv6_get_saddr_eval(net, score, &dst, i);
1334 
1335 				if (minihiscore > miniscore) {
1336 					if (i == IPV6_SADDR_RULE_SCOPE &&
1337 					    score->scopedist > 0) {
1338 						/*
1339 						 * special case:
1340 						 * each remaining entry
1341 						 * has too small (not enough)
1342 						 * scope, because ifa entries
1343 						 * are sorted by their scope
1344 						 * values.
1345 						 */
1346 						goto try_nextdev;
1347 					}
1348 					break;
1349 				} else if (minihiscore < miniscore) {
1350 					if (hiscore->ifa)
1351 						in6_ifa_put(hiscore->ifa);
1352 
1353 					in6_ifa_hold(score->ifa);
1354 
1355 					swap(hiscore, score);
1356 
1357 					/* restore our iterator */
1358 					score->ifa = hiscore->ifa;
1359 
1360 					break;
1361 				}
1362 			}
1363 		}
1364 try_nextdev:
1365 		read_unlock_bh(&idev->lock);
1366 	}
1367 	rcu_read_unlock();
1368 
1369 	if (!hiscore->ifa)
1370 		return -EADDRNOTAVAIL;
1371 
1372 	*saddr = hiscore->ifa->addr;
1373 	in6_ifa_put(hiscore->ifa);
1374 	return 0;
1375 }
1376 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1377 
1378 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1379 		    unsigned char banned_flags)
1380 {
1381 	struct inet6_dev *idev;
1382 	int err = -EADDRNOTAVAIL;
1383 
1384 	rcu_read_lock();
1385 	idev = __in6_dev_get(dev);
1386 	if (idev) {
1387 		struct inet6_ifaddr *ifp;
1388 
1389 		read_lock_bh(&idev->lock);
1390 		list_for_each_entry(ifp, &idev->addr_list, if_list) {
1391 			if (ifp->scope == IFA_LINK &&
1392 			    !(ifp->flags & banned_flags)) {
1393 				*addr = ifp->addr;
1394 				err = 0;
1395 				break;
1396 			}
1397 		}
1398 		read_unlock_bh(&idev->lock);
1399 	}
1400 	rcu_read_unlock();
1401 	return err;
1402 }
1403 
1404 static int ipv6_count_addresses(struct inet6_dev *idev)
1405 {
1406 	int cnt = 0;
1407 	struct inet6_ifaddr *ifp;
1408 
1409 	read_lock_bh(&idev->lock);
1410 	list_for_each_entry(ifp, &idev->addr_list, if_list)
1411 		cnt++;
1412 	read_unlock_bh(&idev->lock);
1413 	return cnt;
1414 }
1415 
1416 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1417 		  struct net_device *dev, int strict)
1418 {
1419 	struct inet6_ifaddr *ifp;
1420 	unsigned int hash = inet6_addr_hash(addr);
1421 
1422 	rcu_read_lock_bh();
1423 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
1424 		if (!net_eq(dev_net(ifp->idev->dev), net))
1425 			continue;
1426 		if (ipv6_addr_equal(&ifp->addr, addr) &&
1427 		    !(ifp->flags&IFA_F_TENTATIVE) &&
1428 		    (dev == NULL || ifp->idev->dev == dev ||
1429 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1430 			rcu_read_unlock_bh();
1431 			return 1;
1432 		}
1433 	}
1434 
1435 	rcu_read_unlock_bh();
1436 	return 0;
1437 }
1438 EXPORT_SYMBOL(ipv6_chk_addr);
1439 
1440 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
1441 			       struct net_device *dev)
1442 {
1443 	unsigned int hash = inet6_addr_hash(addr);
1444 	struct inet6_ifaddr *ifp;
1445 
1446 	hlist_for_each_entry(ifp, &inet6_addr_lst[hash], addr_lst) {
1447 		if (!net_eq(dev_net(ifp->idev->dev), net))
1448 			continue;
1449 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1450 			if (dev == NULL || ifp->idev->dev == dev)
1451 				return true;
1452 		}
1453 	}
1454 	return false;
1455 }
1456 
1457 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
1458 {
1459 	struct inet6_dev *idev;
1460 	struct inet6_ifaddr *ifa;
1461 	int	onlink;
1462 
1463 	onlink = 0;
1464 	rcu_read_lock();
1465 	idev = __in6_dev_get(dev);
1466 	if (idev) {
1467 		read_lock_bh(&idev->lock);
1468 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
1469 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
1470 						   ifa->prefix_len);
1471 			if (onlink)
1472 				break;
1473 		}
1474 		read_unlock_bh(&idev->lock);
1475 	}
1476 	rcu_read_unlock();
1477 	return onlink;
1478 }
1479 EXPORT_SYMBOL(ipv6_chk_prefix);
1480 
1481 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
1482 				     struct net_device *dev, int strict)
1483 {
1484 	struct inet6_ifaddr *ifp, *result = NULL;
1485 	unsigned int hash = inet6_addr_hash(addr);
1486 
1487 	rcu_read_lock_bh();
1488 	hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[hash], addr_lst) {
1489 		if (!net_eq(dev_net(ifp->idev->dev), net))
1490 			continue;
1491 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1492 			if (dev == NULL || ifp->idev->dev == dev ||
1493 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
1494 				result = ifp;
1495 				in6_ifa_hold(ifp);
1496 				break;
1497 			}
1498 		}
1499 	}
1500 	rcu_read_unlock_bh();
1501 
1502 	return result;
1503 }
1504 
1505 /* Gets referenced address, destroys ifaddr */
1506 
1507 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
1508 {
1509 	if (ifp->flags&IFA_F_PERMANENT) {
1510 		spin_lock_bh(&ifp->lock);
1511 		addrconf_del_timer(ifp);
1512 		ifp->flags |= IFA_F_TENTATIVE;
1513 		if (dad_failed)
1514 			ifp->flags |= IFA_F_DADFAILED;
1515 		spin_unlock_bh(&ifp->lock);
1516 		if (dad_failed)
1517 			ipv6_ifa_notify(0, ifp);
1518 		in6_ifa_put(ifp);
1519 #ifdef CONFIG_IPV6_PRIVACY
1520 	} else if (ifp->flags&IFA_F_TEMPORARY) {
1521 		struct inet6_ifaddr *ifpub;
1522 		spin_lock_bh(&ifp->lock);
1523 		ifpub = ifp->ifpub;
1524 		if (ifpub) {
1525 			in6_ifa_hold(ifpub);
1526 			spin_unlock_bh(&ifp->lock);
1527 			ipv6_create_tempaddr(ifpub, ifp);
1528 			in6_ifa_put(ifpub);
1529 		} else {
1530 			spin_unlock_bh(&ifp->lock);
1531 		}
1532 		ipv6_del_addr(ifp);
1533 #endif
1534 	} else
1535 		ipv6_del_addr(ifp);
1536 }
1537 
1538 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
1539 {
1540 	int err = -ENOENT;
1541 
1542 	spin_lock(&ifp->state_lock);
1543 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
1544 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
1545 		err = 0;
1546 	}
1547 	spin_unlock(&ifp->state_lock);
1548 
1549 	return err;
1550 }
1551 
1552 void addrconf_dad_failure(struct inet6_ifaddr *ifp)
1553 {
1554 	struct inet6_dev *idev = ifp->idev;
1555 
1556 	if (addrconf_dad_end(ifp)) {
1557 		in6_ifa_put(ifp);
1558 		return;
1559 	}
1560 
1561 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c detected!\n",
1562 			     ifp->idev->dev->name, &ifp->addr);
1563 
1564 	if (idev->cnf.accept_dad > 1 && !idev->cnf.disable_ipv6) {
1565 		struct in6_addr addr;
1566 
1567 		addr.s6_addr32[0] = htonl(0xfe800000);
1568 		addr.s6_addr32[1] = 0;
1569 
1570 		if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
1571 		    ipv6_addr_equal(&ifp->addr, &addr)) {
1572 			/* DAD failed for link-local based on MAC address */
1573 			idev->cnf.disable_ipv6 = 1;
1574 
1575 			pr_info("%s: IPv6 being disabled!\n",
1576 				ifp->idev->dev->name);
1577 		}
1578 	}
1579 
1580 	addrconf_dad_stop(ifp, 1);
1581 }
1582 
1583 /* Join to solicited addr multicast group. */
1584 
1585 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
1586 {
1587 	struct in6_addr maddr;
1588 
1589 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
1590 		return;
1591 
1592 	addrconf_addr_solict_mult(addr, &maddr);
1593 	ipv6_dev_mc_inc(dev, &maddr);
1594 }
1595 
1596 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
1597 {
1598 	struct in6_addr maddr;
1599 
1600 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
1601 		return;
1602 
1603 	addrconf_addr_solict_mult(addr, &maddr);
1604 	__ipv6_dev_mc_dec(idev, &maddr);
1605 }
1606 
1607 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
1608 {
1609 	struct in6_addr addr;
1610 	if (ifp->prefix_len == 127) /* RFC 6164 */
1611 		return;
1612 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
1613 	if (ipv6_addr_any(&addr))
1614 		return;
1615 	ipv6_dev_ac_inc(ifp->idev->dev, &addr);
1616 }
1617 
1618 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
1619 {
1620 	struct in6_addr addr;
1621 	if (ifp->prefix_len == 127) /* RFC 6164 */
1622 		return;
1623 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
1624 	if (ipv6_addr_any(&addr))
1625 		return;
1626 	__ipv6_dev_ac_dec(ifp->idev, &addr);
1627 }
1628 
1629 static int addrconf_ifid_eui48(u8 *eui, struct net_device *dev)
1630 {
1631 	if (dev->addr_len != ETH_ALEN)
1632 		return -1;
1633 	memcpy(eui, dev->dev_addr, 3);
1634 	memcpy(eui + 5, dev->dev_addr + 3, 3);
1635 
1636 	/*
1637 	 * The zSeries OSA network cards can be shared among various
1638 	 * OS instances, but the OSA cards have only one MAC address.
1639 	 * This leads to duplicate address conflicts in conjunction
1640 	 * with IPv6 if more than one instance uses the same card.
1641 	 *
1642 	 * The driver for these cards can deliver a unique 16-bit
1643 	 * identifier for each instance sharing the same card.  It is
1644 	 * placed instead of 0xFFFE in the interface identifier.  The
1645 	 * "u" bit of the interface identifier is not inverted in this
1646 	 * case.  Hence the resulting interface identifier has local
1647 	 * scope according to RFC2373.
1648 	 */
1649 	if (dev->dev_id) {
1650 		eui[3] = (dev->dev_id >> 8) & 0xFF;
1651 		eui[4] = dev->dev_id & 0xFF;
1652 	} else {
1653 		eui[3] = 0xFF;
1654 		eui[4] = 0xFE;
1655 		eui[0] ^= 2;
1656 	}
1657 	return 0;
1658 }
1659 
1660 static int addrconf_ifid_eui64(u8 *eui, struct net_device *dev)
1661 {
1662 	if (dev->addr_len != IEEE802154_ADDR_LEN)
1663 		return -1;
1664 	memcpy(eui, dev->dev_addr, 8);
1665 	eui[0] ^= 2;
1666 	return 0;
1667 }
1668 
1669 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
1670 {
1671 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
1672 	if (dev->addr_len != ARCNET_ALEN)
1673 		return -1;
1674 	memset(eui, 0, 7);
1675 	eui[7] = *(u8 *)dev->dev_addr;
1676 	return 0;
1677 }
1678 
1679 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
1680 {
1681 	if (dev->addr_len != INFINIBAND_ALEN)
1682 		return -1;
1683 	memcpy(eui, dev->dev_addr + 12, 8);
1684 	eui[0] |= 2;
1685 	return 0;
1686 }
1687 
1688 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
1689 {
1690 	if (addr == 0)
1691 		return -1;
1692 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
1693 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
1694 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
1695 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
1696 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
1697 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
1698 	eui[1] = 0;
1699 	eui[2] = 0x5E;
1700 	eui[3] = 0xFE;
1701 	memcpy(eui + 4, &addr, 4);
1702 	return 0;
1703 }
1704 
1705 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
1706 {
1707 	if (dev->priv_flags & IFF_ISATAP)
1708 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
1709 	return -1;
1710 }
1711 
1712 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
1713 {
1714 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
1715 }
1716 
1717 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
1718 {
1719 	switch (dev->type) {
1720 	case ARPHRD_ETHER:
1721 	case ARPHRD_FDDI:
1722 		return addrconf_ifid_eui48(eui, dev);
1723 	case ARPHRD_ARCNET:
1724 		return addrconf_ifid_arcnet(eui, dev);
1725 	case ARPHRD_INFINIBAND:
1726 		return addrconf_ifid_infiniband(eui, dev);
1727 	case ARPHRD_SIT:
1728 		return addrconf_ifid_sit(eui, dev);
1729 	case ARPHRD_IPGRE:
1730 		return addrconf_ifid_gre(eui, dev);
1731 	case ARPHRD_IEEE802154:
1732 		return addrconf_ifid_eui64(eui, dev);
1733 	}
1734 	return -1;
1735 }
1736 
1737 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
1738 {
1739 	int err = -1;
1740 	struct inet6_ifaddr *ifp;
1741 
1742 	read_lock_bh(&idev->lock);
1743 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
1744 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
1745 			memcpy(eui, ifp->addr.s6_addr+8, 8);
1746 			err = 0;
1747 			break;
1748 		}
1749 	}
1750 	read_unlock_bh(&idev->lock);
1751 	return err;
1752 }
1753 
1754 #ifdef CONFIG_IPV6_PRIVACY
1755 /* (re)generation of randomized interface identifier (RFC 3041 3.2, 3.5) */
1756 static void __ipv6_regen_rndid(struct inet6_dev *idev)
1757 {
1758 regen:
1759 	get_random_bytes(idev->rndid, sizeof(idev->rndid));
1760 	idev->rndid[0] &= ~0x02;
1761 
1762 	/*
1763 	 * <draft-ietf-ipngwg-temp-addresses-v2-00.txt>:
1764 	 * check if generated address is not inappropriate
1765 	 *
1766 	 *  - Reserved subnet anycast (RFC 2526)
1767 	 *	11111101 11....11 1xxxxxxx
1768 	 *  - ISATAP (RFC4214) 6.1
1769 	 *	00-00-5E-FE-xx-xx-xx-xx
1770 	 *  - value 0
1771 	 *  - XXX: already assigned to an address on the device
1772 	 */
1773 	if (idev->rndid[0] == 0xfd &&
1774 	    (idev->rndid[1]&idev->rndid[2]&idev->rndid[3]&idev->rndid[4]&idev->rndid[5]&idev->rndid[6]) == 0xff &&
1775 	    (idev->rndid[7]&0x80))
1776 		goto regen;
1777 	if ((idev->rndid[0]|idev->rndid[1]) == 0) {
1778 		if (idev->rndid[2] == 0x5e && idev->rndid[3] == 0xfe)
1779 			goto regen;
1780 		if ((idev->rndid[2]|idev->rndid[3]|idev->rndid[4]|idev->rndid[5]|idev->rndid[6]|idev->rndid[7]) == 0x00)
1781 			goto regen;
1782 	}
1783 }
1784 
1785 static void ipv6_regen_rndid(unsigned long data)
1786 {
1787 	struct inet6_dev *idev = (struct inet6_dev *) data;
1788 	unsigned long expires;
1789 
1790 	rcu_read_lock_bh();
1791 	write_lock_bh(&idev->lock);
1792 
1793 	if (idev->dead)
1794 		goto out;
1795 
1796 	__ipv6_regen_rndid(idev);
1797 
1798 	expires = jiffies +
1799 		idev->cnf.temp_prefered_lft * HZ -
1800 		idev->cnf.regen_max_retry * idev->cnf.dad_transmits * idev->nd_parms->retrans_time -
1801 		idev->cnf.max_desync_factor * HZ;
1802 	if (time_before(expires, jiffies)) {
1803 		pr_warn("%s: too short regeneration interval; timer disabled for %s\n",
1804 			__func__, idev->dev->name);
1805 		goto out;
1806 	}
1807 
1808 	if (!mod_timer(&idev->regen_timer, expires))
1809 		in6_dev_hold(idev);
1810 
1811 out:
1812 	write_unlock_bh(&idev->lock);
1813 	rcu_read_unlock_bh();
1814 	in6_dev_put(idev);
1815 }
1816 
1817 static void  __ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr)
1818 {
1819 	if (tmpaddr && memcmp(idev->rndid, &tmpaddr->s6_addr[8], 8) == 0)
1820 		__ipv6_regen_rndid(idev);
1821 }
1822 #endif
1823 
1824 /*
1825  *	Add prefix route.
1826  */
1827 
1828 static void
1829 addrconf_prefix_route(struct in6_addr *pfx, int plen, struct net_device *dev,
1830 		      unsigned long expires, u32 flags)
1831 {
1832 	struct fib6_config cfg = {
1833 		.fc_table = RT6_TABLE_PREFIX,
1834 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
1835 		.fc_ifindex = dev->ifindex,
1836 		.fc_expires = expires,
1837 		.fc_dst_len = plen,
1838 		.fc_flags = RTF_UP | flags,
1839 		.fc_nlinfo.nl_net = dev_net(dev),
1840 		.fc_protocol = RTPROT_KERNEL,
1841 	};
1842 
1843 	cfg.fc_dst = *pfx;
1844 
1845 	/* Prevent useless cloning on PtP SIT.
1846 	   This thing is done here expecting that the whole
1847 	   class of non-broadcast devices need not cloning.
1848 	 */
1849 #if IS_ENABLED(CONFIG_IPV6_SIT)
1850 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
1851 		cfg.fc_flags |= RTF_NONEXTHOP;
1852 #endif
1853 
1854 	ip6_route_add(&cfg);
1855 }
1856 
1857 
1858 static struct rt6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
1859 						  int plen,
1860 						  const struct net_device *dev,
1861 						  u32 flags, u32 noflags)
1862 {
1863 	struct fib6_node *fn;
1864 	struct rt6_info *rt = NULL;
1865 	struct fib6_table *table;
1866 
1867 	table = fib6_get_table(dev_net(dev), RT6_TABLE_PREFIX);
1868 	if (table == NULL)
1869 		return NULL;
1870 
1871 	read_lock_bh(&table->tb6_lock);
1872 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0);
1873 	if (!fn)
1874 		goto out;
1875 	for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
1876 		if (rt->dst.dev->ifindex != dev->ifindex)
1877 			continue;
1878 		if ((rt->rt6i_flags & flags) != flags)
1879 			continue;
1880 		if ((rt->rt6i_flags & noflags) != 0)
1881 			continue;
1882 		dst_hold(&rt->dst);
1883 		break;
1884 	}
1885 out:
1886 	read_unlock_bh(&table->tb6_lock);
1887 	return rt;
1888 }
1889 
1890 
1891 /* Create "default" multicast route to the interface */
1892 
1893 static void addrconf_add_mroute(struct net_device *dev)
1894 {
1895 	struct fib6_config cfg = {
1896 		.fc_table = RT6_TABLE_LOCAL,
1897 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
1898 		.fc_ifindex = dev->ifindex,
1899 		.fc_dst_len = 8,
1900 		.fc_flags = RTF_UP,
1901 		.fc_nlinfo.nl_net = dev_net(dev),
1902 	};
1903 
1904 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
1905 
1906 	ip6_route_add(&cfg);
1907 }
1908 
1909 #if IS_ENABLED(CONFIG_IPV6_SIT)
1910 static void sit_route_add(struct net_device *dev)
1911 {
1912 	struct fib6_config cfg = {
1913 		.fc_table = RT6_TABLE_MAIN,
1914 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
1915 		.fc_ifindex = dev->ifindex,
1916 		.fc_dst_len = 96,
1917 		.fc_flags = RTF_UP | RTF_NONEXTHOP,
1918 		.fc_nlinfo.nl_net = dev_net(dev),
1919 	};
1920 
1921 	/* prefix length - 96 bits "::d.d.d.d" */
1922 	ip6_route_add(&cfg);
1923 }
1924 #endif
1925 
1926 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
1927 {
1928 	struct inet6_dev *idev;
1929 
1930 	ASSERT_RTNL();
1931 
1932 	idev = ipv6_find_idev(dev);
1933 	if (!idev)
1934 		return ERR_PTR(-ENOBUFS);
1935 
1936 	if (idev->cnf.disable_ipv6)
1937 		return ERR_PTR(-EACCES);
1938 
1939 	/* Add default multicast route */
1940 	if (!(dev->flags & IFF_LOOPBACK))
1941 		addrconf_add_mroute(dev);
1942 
1943 	return idev;
1944 }
1945 
1946 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
1947 {
1948 	struct prefix_info *pinfo;
1949 	__u32 valid_lft;
1950 	__u32 prefered_lft;
1951 	int addr_type;
1952 	struct inet6_dev *in6_dev;
1953 	struct net *net = dev_net(dev);
1954 
1955 	pinfo = (struct prefix_info *) opt;
1956 
1957 	if (len < sizeof(struct prefix_info)) {
1958 		ADBG(("addrconf: prefix option too short\n"));
1959 		return;
1960 	}
1961 
1962 	/*
1963 	 *	Validation checks ([ADDRCONF], page 19)
1964 	 */
1965 
1966 	addr_type = ipv6_addr_type(&pinfo->prefix);
1967 
1968 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
1969 		return;
1970 
1971 	valid_lft = ntohl(pinfo->valid);
1972 	prefered_lft = ntohl(pinfo->prefered);
1973 
1974 	if (prefered_lft > valid_lft) {
1975 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
1976 		return;
1977 	}
1978 
1979 	in6_dev = in6_dev_get(dev);
1980 
1981 	if (in6_dev == NULL) {
1982 		net_dbg_ratelimited("addrconf: device %s not configured\n",
1983 				    dev->name);
1984 		return;
1985 	}
1986 
1987 	/*
1988 	 *	Two things going on here:
1989 	 *	1) Add routes for on-link prefixes
1990 	 *	2) Configure prefixes with the auto flag set
1991 	 */
1992 
1993 	if (pinfo->onlink) {
1994 		struct rt6_info *rt;
1995 		unsigned long rt_expires;
1996 
1997 		/* Avoid arithmetic overflow. Really, we could
1998 		 * save rt_expires in seconds, likely valid_lft,
1999 		 * but it would require division in fib gc, that it
2000 		 * not good.
2001 		 */
2002 		if (HZ > USER_HZ)
2003 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2004 		else
2005 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2006 
2007 		if (addrconf_finite_timeout(rt_expires))
2008 			rt_expires *= HZ;
2009 
2010 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2011 					       pinfo->prefix_len,
2012 					       dev,
2013 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2014 					       RTF_GATEWAY | RTF_DEFAULT);
2015 
2016 		if (rt) {
2017 			/* Autoconf prefix route */
2018 			if (valid_lft == 0) {
2019 				ip6_del_rt(rt);
2020 				rt = NULL;
2021 			} else if (addrconf_finite_timeout(rt_expires)) {
2022 				/* not infinity */
2023 				rt6_set_expires(rt, jiffies + rt_expires);
2024 			} else {
2025 				rt6_clean_expires(rt);
2026 			}
2027 		} else if (valid_lft) {
2028 			clock_t expires = 0;
2029 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2030 			if (addrconf_finite_timeout(rt_expires)) {
2031 				/* not infinity */
2032 				flags |= RTF_EXPIRES;
2033 				expires = jiffies_to_clock_t(rt_expires);
2034 			}
2035 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2036 					      dev, expires, flags);
2037 		}
2038 		ip6_rt_put(rt);
2039 	}
2040 
2041 	/* Try to figure out our local address for this prefix */
2042 
2043 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
2044 		struct inet6_ifaddr *ifp;
2045 		struct in6_addr addr;
2046 		int create = 0, update_lft = 0;
2047 
2048 		if (pinfo->prefix_len == 64) {
2049 			memcpy(&addr, &pinfo->prefix, 8);
2050 			if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2051 			    ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2052 				in6_dev_put(in6_dev);
2053 				return;
2054 			}
2055 			goto ok;
2056 		}
2057 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2058 				    pinfo->prefix_len);
2059 		in6_dev_put(in6_dev);
2060 		return;
2061 
2062 ok:
2063 
2064 		ifp = ipv6_get_ifaddr(net, &addr, dev, 1);
2065 
2066 		if (ifp == NULL && valid_lft) {
2067 			int max_addresses = in6_dev->cnf.max_addresses;
2068 			u32 addr_flags = 0;
2069 
2070 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2071 			if (in6_dev->cnf.optimistic_dad &&
2072 			    !net->ipv6.devconf_all->forwarding && sllao)
2073 				addr_flags = IFA_F_OPTIMISTIC;
2074 #endif
2075 
2076 			/* Do not allow to create too much of autoconfigured
2077 			 * addresses; this would be too easy way to crash kernel.
2078 			 */
2079 			if (!max_addresses ||
2080 			    ipv6_count_addresses(in6_dev) < max_addresses)
2081 				ifp = ipv6_add_addr(in6_dev, &addr, pinfo->prefix_len,
2082 						    addr_type&IPV6_ADDR_SCOPE_MASK,
2083 						    addr_flags);
2084 
2085 			if (IS_ERR_OR_NULL(ifp)) {
2086 				in6_dev_put(in6_dev);
2087 				return;
2088 			}
2089 
2090 			update_lft = create = 1;
2091 			ifp->cstamp = jiffies;
2092 			addrconf_dad_start(ifp);
2093 		}
2094 
2095 		if (ifp) {
2096 			int flags;
2097 			unsigned long now;
2098 #ifdef CONFIG_IPV6_PRIVACY
2099 			struct inet6_ifaddr *ift;
2100 #endif
2101 			u32 stored_lft;
2102 
2103 			/* update lifetime (RFC2462 5.5.3 e) */
2104 			spin_lock(&ifp->lock);
2105 			now = jiffies;
2106 			if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2107 				stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2108 			else
2109 				stored_lft = 0;
2110 			if (!update_lft && stored_lft) {
2111 				if (valid_lft > MIN_VALID_LIFETIME ||
2112 				    valid_lft > stored_lft)
2113 					update_lft = 1;
2114 				else if (stored_lft <= MIN_VALID_LIFETIME) {
2115 					/* valid_lft <= stored_lft is always true */
2116 					/*
2117 					 * RFC 4862 Section 5.5.3e:
2118 					 * "Note that the preferred lifetime of
2119 					 *  the corresponding address is always
2120 					 *  reset to the Preferred Lifetime in
2121 					 *  the received Prefix Information
2122 					 *  option, regardless of whether the
2123 					 *  valid lifetime is also reset or
2124 					 *  ignored."
2125 					 *
2126 					 *  So if the preferred lifetime in
2127 					 *  this advertisement is different
2128 					 *  than what we have stored, but the
2129 					 *  valid lifetime is invalid, just
2130 					 *  reset prefered_lft.
2131 					 *
2132 					 *  We must set the valid lifetime
2133 					 *  to the stored lifetime since we'll
2134 					 *  be updating the timestamp below,
2135 					 *  else we'll set it back to the
2136 					 *  minimum.
2137 					 */
2138 					if (prefered_lft != ifp->prefered_lft) {
2139 						valid_lft = stored_lft;
2140 						update_lft = 1;
2141 					}
2142 				} else {
2143 					valid_lft = MIN_VALID_LIFETIME;
2144 					if (valid_lft < prefered_lft)
2145 						prefered_lft = valid_lft;
2146 					update_lft = 1;
2147 				}
2148 			}
2149 
2150 			if (update_lft) {
2151 				ifp->valid_lft = valid_lft;
2152 				ifp->prefered_lft = prefered_lft;
2153 				ifp->tstamp = now;
2154 				flags = ifp->flags;
2155 				ifp->flags &= ~IFA_F_DEPRECATED;
2156 				spin_unlock(&ifp->lock);
2157 
2158 				if (!(flags&IFA_F_TENTATIVE))
2159 					ipv6_ifa_notify(0, ifp);
2160 			} else
2161 				spin_unlock(&ifp->lock);
2162 
2163 #ifdef CONFIG_IPV6_PRIVACY
2164 			read_lock_bh(&in6_dev->lock);
2165 			/* update all temporary addresses in the list */
2166 			list_for_each_entry(ift, &in6_dev->tempaddr_list,
2167 					    tmp_list) {
2168 				int age, max_valid, max_prefered;
2169 
2170 				if (ifp != ift->ifpub)
2171 					continue;
2172 
2173 				/*
2174 				 * RFC 4941 section 3.3:
2175 				 * If a received option will extend the lifetime
2176 				 * of a public address, the lifetimes of
2177 				 * temporary addresses should be extended,
2178 				 * subject to the overall constraint that no
2179 				 * temporary addresses should ever remain
2180 				 * "valid" or "preferred" for a time longer than
2181 				 * (TEMP_VALID_LIFETIME) or
2182 				 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR),
2183 				 * respectively.
2184 				 */
2185 				age = (now - ift->cstamp) / HZ;
2186 				max_valid = in6_dev->cnf.temp_valid_lft - age;
2187 				if (max_valid < 0)
2188 					max_valid = 0;
2189 
2190 				max_prefered = in6_dev->cnf.temp_prefered_lft -
2191 					       in6_dev->cnf.max_desync_factor -
2192 					       age;
2193 				if (max_prefered < 0)
2194 					max_prefered = 0;
2195 
2196 				if (valid_lft > max_valid)
2197 					valid_lft = max_valid;
2198 
2199 				if (prefered_lft > max_prefered)
2200 					prefered_lft = max_prefered;
2201 
2202 				spin_lock(&ift->lock);
2203 				flags = ift->flags;
2204 				ift->valid_lft = valid_lft;
2205 				ift->prefered_lft = prefered_lft;
2206 				ift->tstamp = now;
2207 				if (prefered_lft > 0)
2208 					ift->flags &= ~IFA_F_DEPRECATED;
2209 
2210 				spin_unlock(&ift->lock);
2211 				if (!(flags&IFA_F_TENTATIVE))
2212 					ipv6_ifa_notify(0, ift);
2213 			}
2214 
2215 			if ((create || list_empty(&in6_dev->tempaddr_list)) && in6_dev->cnf.use_tempaddr > 0) {
2216 				/*
2217 				 * When a new public address is created as
2218 				 * described in [ADDRCONF], also create a new
2219 				 * temporary address. Also create a temporary
2220 				 * address if it's enabled but no temporary
2221 				 * address currently exists.
2222 				 */
2223 				read_unlock_bh(&in6_dev->lock);
2224 				ipv6_create_tempaddr(ifp, NULL);
2225 			} else {
2226 				read_unlock_bh(&in6_dev->lock);
2227 			}
2228 #endif
2229 			in6_ifa_put(ifp);
2230 			addrconf_verify(0);
2231 		}
2232 	}
2233 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2234 	in6_dev_put(in6_dev);
2235 }
2236 
2237 /*
2238  *	Set destination address.
2239  *	Special case for SIT interfaces where we create a new "virtual"
2240  *	device.
2241  */
2242 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2243 {
2244 	struct in6_ifreq ireq;
2245 	struct net_device *dev;
2246 	int err = -EINVAL;
2247 
2248 	rtnl_lock();
2249 
2250 	err = -EFAULT;
2251 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2252 		goto err_exit;
2253 
2254 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2255 
2256 	err = -ENODEV;
2257 	if (dev == NULL)
2258 		goto err_exit;
2259 
2260 #if IS_ENABLED(CONFIG_IPV6_SIT)
2261 	if (dev->type == ARPHRD_SIT) {
2262 		const struct net_device_ops *ops = dev->netdev_ops;
2263 		struct ifreq ifr;
2264 		struct ip_tunnel_parm p;
2265 
2266 		err = -EADDRNOTAVAIL;
2267 		if (!(ipv6_addr_type(&ireq.ifr6_addr) & IPV6_ADDR_COMPATv4))
2268 			goto err_exit;
2269 
2270 		memset(&p, 0, sizeof(p));
2271 		p.iph.daddr = ireq.ifr6_addr.s6_addr32[3];
2272 		p.iph.saddr = 0;
2273 		p.iph.version = 4;
2274 		p.iph.ihl = 5;
2275 		p.iph.protocol = IPPROTO_IPV6;
2276 		p.iph.ttl = 64;
2277 		ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
2278 
2279 		if (ops->ndo_do_ioctl) {
2280 			mm_segment_t oldfs = get_fs();
2281 
2282 			set_fs(KERNEL_DS);
2283 			err = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
2284 			set_fs(oldfs);
2285 		} else
2286 			err = -EOPNOTSUPP;
2287 
2288 		if (err == 0) {
2289 			err = -ENOBUFS;
2290 			dev = __dev_get_by_name(net, p.name);
2291 			if (!dev)
2292 				goto err_exit;
2293 			err = dev_open(dev);
2294 		}
2295 	}
2296 #endif
2297 
2298 err_exit:
2299 	rtnl_unlock();
2300 	return err;
2301 }
2302 
2303 /*
2304  *	Manual configuration of address on an interface
2305  */
2306 static int inet6_addr_add(struct net *net, int ifindex, const struct in6_addr *pfx,
2307 			  unsigned int plen, __u8 ifa_flags, __u32 prefered_lft,
2308 			  __u32 valid_lft)
2309 {
2310 	struct inet6_ifaddr *ifp;
2311 	struct inet6_dev *idev;
2312 	struct net_device *dev;
2313 	int scope;
2314 	u32 flags;
2315 	clock_t expires;
2316 	unsigned long timeout;
2317 
2318 	ASSERT_RTNL();
2319 
2320 	if (plen > 128)
2321 		return -EINVAL;
2322 
2323 	/* check the lifetime */
2324 	if (!valid_lft || prefered_lft > valid_lft)
2325 		return -EINVAL;
2326 
2327 	dev = __dev_get_by_index(net, ifindex);
2328 	if (!dev)
2329 		return -ENODEV;
2330 
2331 	idev = addrconf_add_dev(dev);
2332 	if (IS_ERR(idev))
2333 		return PTR_ERR(idev);
2334 
2335 	scope = ipv6_addr_scope(pfx);
2336 
2337 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
2338 	if (addrconf_finite_timeout(timeout)) {
2339 		expires = jiffies_to_clock_t(timeout * HZ);
2340 		valid_lft = timeout;
2341 		flags = RTF_EXPIRES;
2342 	} else {
2343 		expires = 0;
2344 		flags = 0;
2345 		ifa_flags |= IFA_F_PERMANENT;
2346 	}
2347 
2348 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
2349 	if (addrconf_finite_timeout(timeout)) {
2350 		if (timeout == 0)
2351 			ifa_flags |= IFA_F_DEPRECATED;
2352 		prefered_lft = timeout;
2353 	}
2354 
2355 	ifp = ipv6_add_addr(idev, pfx, plen, scope, ifa_flags);
2356 
2357 	if (!IS_ERR(ifp)) {
2358 		spin_lock_bh(&ifp->lock);
2359 		ifp->valid_lft = valid_lft;
2360 		ifp->prefered_lft = prefered_lft;
2361 		ifp->tstamp = jiffies;
2362 		spin_unlock_bh(&ifp->lock);
2363 
2364 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, dev,
2365 				      expires, flags);
2366 		/*
2367 		 * Note that section 3.1 of RFC 4429 indicates
2368 		 * that the Optimistic flag should not be set for
2369 		 * manually configured addresses
2370 		 */
2371 		addrconf_dad_start(ifp);
2372 		in6_ifa_put(ifp);
2373 		addrconf_verify(0);
2374 		return 0;
2375 	}
2376 
2377 	return PTR_ERR(ifp);
2378 }
2379 
2380 static int inet6_addr_del(struct net *net, int ifindex, const struct in6_addr *pfx,
2381 			  unsigned int plen)
2382 {
2383 	struct inet6_ifaddr *ifp;
2384 	struct inet6_dev *idev;
2385 	struct net_device *dev;
2386 
2387 	if (plen > 128)
2388 		return -EINVAL;
2389 
2390 	dev = __dev_get_by_index(net, ifindex);
2391 	if (!dev)
2392 		return -ENODEV;
2393 
2394 	if ((idev = __in6_dev_get(dev)) == NULL)
2395 		return -ENXIO;
2396 
2397 	read_lock_bh(&idev->lock);
2398 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
2399 		if (ifp->prefix_len == plen &&
2400 		    ipv6_addr_equal(pfx, &ifp->addr)) {
2401 			in6_ifa_hold(ifp);
2402 			read_unlock_bh(&idev->lock);
2403 
2404 			ipv6_del_addr(ifp);
2405 
2406 			/* If the last address is deleted administratively,
2407 			   disable IPv6 on this interface.
2408 			 */
2409 			if (list_empty(&idev->addr_list))
2410 				addrconf_ifdown(idev->dev, 1);
2411 			return 0;
2412 		}
2413 	}
2414 	read_unlock_bh(&idev->lock);
2415 	return -EADDRNOTAVAIL;
2416 }
2417 
2418 
2419 int addrconf_add_ifaddr(struct net *net, void __user *arg)
2420 {
2421 	struct in6_ifreq ireq;
2422 	int err;
2423 
2424 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2425 		return -EPERM;
2426 
2427 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2428 		return -EFAULT;
2429 
2430 	rtnl_lock();
2431 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &ireq.ifr6_addr,
2432 			     ireq.ifr6_prefixlen, IFA_F_PERMANENT,
2433 			     INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
2434 	rtnl_unlock();
2435 	return err;
2436 }
2437 
2438 int addrconf_del_ifaddr(struct net *net, void __user *arg)
2439 {
2440 	struct in6_ifreq ireq;
2441 	int err;
2442 
2443 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2444 		return -EPERM;
2445 
2446 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2447 		return -EFAULT;
2448 
2449 	rtnl_lock();
2450 	err = inet6_addr_del(net, ireq.ifr6_ifindex, &ireq.ifr6_addr,
2451 			     ireq.ifr6_prefixlen);
2452 	rtnl_unlock();
2453 	return err;
2454 }
2455 
2456 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
2457 		     int plen, int scope)
2458 {
2459 	struct inet6_ifaddr *ifp;
2460 
2461 	ifp = ipv6_add_addr(idev, addr, plen, scope, IFA_F_PERMANENT);
2462 	if (!IS_ERR(ifp)) {
2463 		spin_lock_bh(&ifp->lock);
2464 		ifp->flags &= ~IFA_F_TENTATIVE;
2465 		spin_unlock_bh(&ifp->lock);
2466 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
2467 		in6_ifa_put(ifp);
2468 	}
2469 }
2470 
2471 #if IS_ENABLED(CONFIG_IPV6_SIT)
2472 static void sit_add_v4_addrs(struct inet6_dev *idev)
2473 {
2474 	struct in6_addr addr;
2475 	struct net_device *dev;
2476 	struct net *net = dev_net(idev->dev);
2477 	int scope;
2478 
2479 	ASSERT_RTNL();
2480 
2481 	memset(&addr, 0, sizeof(struct in6_addr));
2482 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
2483 
2484 	if (idev->dev->flags&IFF_POINTOPOINT) {
2485 		addr.s6_addr32[0] = htonl(0xfe800000);
2486 		scope = IFA_LINK;
2487 	} else {
2488 		scope = IPV6_ADDR_COMPATv4;
2489 	}
2490 
2491 	if (addr.s6_addr32[3]) {
2492 		add_addr(idev, &addr, 128, scope);
2493 		return;
2494 	}
2495 
2496 	for_each_netdev(net, dev) {
2497 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
2498 		if (in_dev && (dev->flags & IFF_UP)) {
2499 			struct in_ifaddr *ifa;
2500 
2501 			int flag = scope;
2502 
2503 			for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
2504 				int plen;
2505 
2506 				addr.s6_addr32[3] = ifa->ifa_local;
2507 
2508 				if (ifa->ifa_scope == RT_SCOPE_LINK)
2509 					continue;
2510 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
2511 					if (idev->dev->flags&IFF_POINTOPOINT)
2512 						continue;
2513 					flag |= IFA_HOST;
2514 				}
2515 				if (idev->dev->flags&IFF_POINTOPOINT)
2516 					plen = 64;
2517 				else
2518 					plen = 96;
2519 
2520 				add_addr(idev, &addr, plen, flag);
2521 			}
2522 		}
2523 	}
2524 }
2525 #endif
2526 
2527 static void init_loopback(struct net_device *dev)
2528 {
2529 	struct inet6_dev  *idev;
2530 	struct net_device *sp_dev;
2531 	struct inet6_ifaddr *sp_ifa;
2532 	struct rt6_info *sp_rt;
2533 
2534 	/* ::1 */
2535 
2536 	ASSERT_RTNL();
2537 
2538 	if ((idev = ipv6_find_idev(dev)) == NULL) {
2539 		pr_debug("%s: add_dev failed\n", __func__);
2540 		return;
2541 	}
2542 
2543 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST);
2544 
2545 	/* Add routes to other interface's IPv6 addresses */
2546 	for_each_netdev(dev_net(dev), sp_dev) {
2547 		if (!strcmp(sp_dev->name, dev->name))
2548 			continue;
2549 
2550 		idev = __in6_dev_get(sp_dev);
2551 		if (!idev)
2552 			continue;
2553 
2554 		read_lock_bh(&idev->lock);
2555 		list_for_each_entry(sp_ifa, &idev->addr_list, if_list) {
2556 
2557 			if (sp_ifa->flags & (IFA_F_DADFAILED | IFA_F_TENTATIVE))
2558 				continue;
2559 
2560 			sp_rt = addrconf_dst_alloc(idev, &sp_ifa->addr, 0);
2561 
2562 			/* Failure cases are ignored */
2563 			if (!IS_ERR(sp_rt))
2564 				ip6_ins_rt(sp_rt);
2565 		}
2566 		read_unlock_bh(&idev->lock);
2567 	}
2568 }
2569 
2570 static void addrconf_add_linklocal(struct inet6_dev *idev, const struct in6_addr *addr)
2571 {
2572 	struct inet6_ifaddr *ifp;
2573 	u32 addr_flags = IFA_F_PERMANENT;
2574 
2575 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2576 	if (idev->cnf.optimistic_dad &&
2577 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
2578 		addr_flags |= IFA_F_OPTIMISTIC;
2579 #endif
2580 
2581 
2582 	ifp = ipv6_add_addr(idev, addr, 64, IFA_LINK, addr_flags);
2583 	if (!IS_ERR(ifp)) {
2584 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, idev->dev, 0, 0);
2585 		addrconf_dad_start(ifp);
2586 		in6_ifa_put(ifp);
2587 	}
2588 }
2589 
2590 static void addrconf_dev_config(struct net_device *dev)
2591 {
2592 	struct in6_addr addr;
2593 	struct inet6_dev *idev;
2594 
2595 	ASSERT_RTNL();
2596 
2597 	if ((dev->type != ARPHRD_ETHER) &&
2598 	    (dev->type != ARPHRD_FDDI) &&
2599 	    (dev->type != ARPHRD_ARCNET) &&
2600 	    (dev->type != ARPHRD_INFINIBAND) &&
2601 	    (dev->type != ARPHRD_IEEE802154)) {
2602 		/* Alas, we support only Ethernet autoconfiguration. */
2603 		return;
2604 	}
2605 
2606 	idev = addrconf_add_dev(dev);
2607 	if (IS_ERR(idev))
2608 		return;
2609 
2610 	memset(&addr, 0, sizeof(struct in6_addr));
2611 	addr.s6_addr32[0] = htonl(0xFE800000);
2612 
2613 	if (ipv6_generate_eui64(addr.s6_addr + 8, dev) == 0)
2614 		addrconf_add_linklocal(idev, &addr);
2615 }
2616 
2617 #if IS_ENABLED(CONFIG_IPV6_SIT)
2618 static void addrconf_sit_config(struct net_device *dev)
2619 {
2620 	struct inet6_dev *idev;
2621 
2622 	ASSERT_RTNL();
2623 
2624 	/*
2625 	 * Configure the tunnel with one of our IPv4
2626 	 * addresses... we should configure all of
2627 	 * our v4 addrs in the tunnel
2628 	 */
2629 
2630 	if ((idev = ipv6_find_idev(dev)) == NULL) {
2631 		pr_debug("%s: add_dev failed\n", __func__);
2632 		return;
2633 	}
2634 
2635 	if (dev->priv_flags & IFF_ISATAP) {
2636 		struct in6_addr addr;
2637 
2638 		ipv6_addr_set(&addr,  htonl(0xFE800000), 0, 0, 0);
2639 		addrconf_prefix_route(&addr, 64, dev, 0, 0);
2640 		if (!ipv6_generate_eui64(addr.s6_addr + 8, dev))
2641 			addrconf_add_linklocal(idev, &addr);
2642 		return;
2643 	}
2644 
2645 	sit_add_v4_addrs(idev);
2646 
2647 	if (dev->flags&IFF_POINTOPOINT)
2648 		addrconf_add_mroute(dev);
2649 	else
2650 		sit_route_add(dev);
2651 }
2652 #endif
2653 
2654 #if IS_ENABLED(CONFIG_NET_IPGRE)
2655 static void addrconf_gre_config(struct net_device *dev)
2656 {
2657 	struct inet6_dev *idev;
2658 	struct in6_addr addr;
2659 
2660 	pr_info("%s(%s)\n", __func__, dev->name);
2661 
2662 	ASSERT_RTNL();
2663 
2664 	if ((idev = ipv6_find_idev(dev)) == NULL) {
2665 		pr_debug("%s: add_dev failed\n", __func__);
2666 		return;
2667 	}
2668 
2669 	ipv6_addr_set(&addr,  htonl(0xFE800000), 0, 0, 0);
2670 	addrconf_prefix_route(&addr, 64, dev, 0, 0);
2671 
2672 	if (!ipv6_generate_eui64(addr.s6_addr + 8, dev))
2673 		addrconf_add_linklocal(idev, &addr);
2674 }
2675 #endif
2676 
2677 static inline int
2678 ipv6_inherit_linklocal(struct inet6_dev *idev, struct net_device *link_dev)
2679 {
2680 	struct in6_addr lladdr;
2681 
2682 	if (!ipv6_get_lladdr(link_dev, &lladdr, IFA_F_TENTATIVE)) {
2683 		addrconf_add_linklocal(idev, &lladdr);
2684 		return 0;
2685 	}
2686 	return -1;
2687 }
2688 
2689 static void ip6_tnl_add_linklocal(struct inet6_dev *idev)
2690 {
2691 	struct net_device *link_dev;
2692 	struct net *net = dev_net(idev->dev);
2693 
2694 	/* first try to inherit the link-local address from the link device */
2695 	if (idev->dev->iflink &&
2696 	    (link_dev = __dev_get_by_index(net, idev->dev->iflink))) {
2697 		if (!ipv6_inherit_linklocal(idev, link_dev))
2698 			return;
2699 	}
2700 	/* then try to inherit it from any device */
2701 	for_each_netdev(net, link_dev) {
2702 		if (!ipv6_inherit_linklocal(idev, link_dev))
2703 			return;
2704 	}
2705 	pr_debug("init ip6-ip6: add_linklocal failed\n");
2706 }
2707 
2708 /*
2709  * Autoconfigure tunnel with a link-local address so routing protocols,
2710  * DHCPv6, MLD etc. can be run over the virtual link
2711  */
2712 
2713 static void addrconf_ip6_tnl_config(struct net_device *dev)
2714 {
2715 	struct inet6_dev *idev;
2716 
2717 	ASSERT_RTNL();
2718 
2719 	idev = addrconf_add_dev(dev);
2720 	if (IS_ERR(idev)) {
2721 		pr_debug("init ip6-ip6: add_dev failed\n");
2722 		return;
2723 	}
2724 	ip6_tnl_add_linklocal(idev);
2725 }
2726 
2727 static int addrconf_notify(struct notifier_block *this, unsigned long event,
2728 			   void *data)
2729 {
2730 	struct net_device *dev = (struct net_device *) data;
2731 	struct inet6_dev *idev = __in6_dev_get(dev);
2732 	int run_pending = 0;
2733 	int err;
2734 
2735 	switch (event) {
2736 	case NETDEV_REGISTER:
2737 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
2738 			idev = ipv6_add_dev(dev);
2739 			if (!idev)
2740 				return notifier_from_errno(-ENOMEM);
2741 		}
2742 		break;
2743 
2744 	case NETDEV_UP:
2745 	case NETDEV_CHANGE:
2746 		if (dev->flags & IFF_SLAVE)
2747 			break;
2748 
2749 		if (event == NETDEV_UP) {
2750 			if (!addrconf_qdisc_ok(dev)) {
2751 				/* device is not ready yet. */
2752 				pr_info("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
2753 					dev->name);
2754 				break;
2755 			}
2756 
2757 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
2758 				idev = ipv6_add_dev(dev);
2759 
2760 			if (idev) {
2761 				idev->if_flags |= IF_READY;
2762 				run_pending = 1;
2763 			}
2764 		} else {
2765 			if (!addrconf_qdisc_ok(dev)) {
2766 				/* device is still not ready. */
2767 				break;
2768 			}
2769 
2770 			if (idev) {
2771 				if (idev->if_flags & IF_READY)
2772 					/* device is already configured. */
2773 					break;
2774 				idev->if_flags |= IF_READY;
2775 			}
2776 
2777 			pr_info("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
2778 				dev->name);
2779 
2780 			run_pending = 1;
2781 		}
2782 
2783 		switch (dev->type) {
2784 #if IS_ENABLED(CONFIG_IPV6_SIT)
2785 		case ARPHRD_SIT:
2786 			addrconf_sit_config(dev);
2787 			break;
2788 #endif
2789 #if IS_ENABLED(CONFIG_NET_IPGRE)
2790 		case ARPHRD_IPGRE:
2791 			addrconf_gre_config(dev);
2792 			break;
2793 #endif
2794 		case ARPHRD_TUNNEL6:
2795 			addrconf_ip6_tnl_config(dev);
2796 			break;
2797 		case ARPHRD_LOOPBACK:
2798 			init_loopback(dev);
2799 			break;
2800 
2801 		default:
2802 			addrconf_dev_config(dev);
2803 			break;
2804 		}
2805 
2806 		if (idev) {
2807 			if (run_pending)
2808 				addrconf_dad_run(idev);
2809 
2810 			/*
2811 			 * If the MTU changed during the interface down,
2812 			 * when the interface up, the changed MTU must be
2813 			 * reflected in the idev as well as routers.
2814 			 */
2815 			if (idev->cnf.mtu6 != dev->mtu &&
2816 			    dev->mtu >= IPV6_MIN_MTU) {
2817 				rt6_mtu_change(dev, dev->mtu);
2818 				idev->cnf.mtu6 = dev->mtu;
2819 			}
2820 			idev->tstamp = jiffies;
2821 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
2822 
2823 			/*
2824 			 * If the changed mtu during down is lower than
2825 			 * IPV6_MIN_MTU stop IPv6 on this interface.
2826 			 */
2827 			if (dev->mtu < IPV6_MIN_MTU)
2828 				addrconf_ifdown(dev, 1);
2829 		}
2830 		break;
2831 
2832 	case NETDEV_CHANGEMTU:
2833 		if (idev && dev->mtu >= IPV6_MIN_MTU) {
2834 			rt6_mtu_change(dev, dev->mtu);
2835 			idev->cnf.mtu6 = dev->mtu;
2836 			break;
2837 		}
2838 
2839 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
2840 			idev = ipv6_add_dev(dev);
2841 			if (idev)
2842 				break;
2843 		}
2844 
2845 		/*
2846 		 * MTU falled under IPV6_MIN_MTU.
2847 		 * Stop IPv6 on this interface.
2848 		 */
2849 
2850 	case NETDEV_DOWN:
2851 	case NETDEV_UNREGISTER:
2852 		/*
2853 		 *	Remove all addresses from this interface.
2854 		 */
2855 		addrconf_ifdown(dev, event != NETDEV_DOWN);
2856 		break;
2857 
2858 	case NETDEV_CHANGENAME:
2859 		if (idev) {
2860 			snmp6_unregister_dev(idev);
2861 			addrconf_sysctl_unregister(idev);
2862 			addrconf_sysctl_register(idev);
2863 			err = snmp6_register_dev(idev);
2864 			if (err)
2865 				return notifier_from_errno(err);
2866 		}
2867 		break;
2868 
2869 	case NETDEV_PRE_TYPE_CHANGE:
2870 	case NETDEV_POST_TYPE_CHANGE:
2871 		addrconf_type_change(dev, event);
2872 		break;
2873 	}
2874 
2875 	return NOTIFY_OK;
2876 }
2877 
2878 /*
2879  *	addrconf module should be notified of a device going up
2880  */
2881 static struct notifier_block ipv6_dev_notf = {
2882 	.notifier_call = addrconf_notify,
2883 };
2884 
2885 static void addrconf_type_change(struct net_device *dev, unsigned long event)
2886 {
2887 	struct inet6_dev *idev;
2888 	ASSERT_RTNL();
2889 
2890 	idev = __in6_dev_get(dev);
2891 
2892 	if (event == NETDEV_POST_TYPE_CHANGE)
2893 		ipv6_mc_remap(idev);
2894 	else if (event == NETDEV_PRE_TYPE_CHANGE)
2895 		ipv6_mc_unmap(idev);
2896 }
2897 
2898 static int addrconf_ifdown(struct net_device *dev, int how)
2899 {
2900 	struct net *net = dev_net(dev);
2901 	struct inet6_dev *idev;
2902 	struct inet6_ifaddr *ifa;
2903 	int state, i;
2904 
2905 	ASSERT_RTNL();
2906 
2907 	rt6_ifdown(net, dev);
2908 	neigh_ifdown(&nd_tbl, dev);
2909 
2910 	idev = __in6_dev_get(dev);
2911 	if (idev == NULL)
2912 		return -ENODEV;
2913 
2914 	/*
2915 	 * Step 1: remove reference to ipv6 device from parent device.
2916 	 *	   Do not dev_put!
2917 	 */
2918 	if (how) {
2919 		idev->dead = 1;
2920 
2921 		/* protected by rtnl_lock */
2922 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
2923 
2924 		/* Step 1.5: remove snmp6 entry */
2925 		snmp6_unregister_dev(idev);
2926 
2927 	}
2928 
2929 	/* Step 2: clear hash table */
2930 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
2931 		struct hlist_head *h = &inet6_addr_lst[i];
2932 
2933 		spin_lock_bh(&addrconf_hash_lock);
2934 	restart:
2935 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
2936 			if (ifa->idev == idev) {
2937 				hlist_del_init_rcu(&ifa->addr_lst);
2938 				addrconf_del_timer(ifa);
2939 				goto restart;
2940 			}
2941 		}
2942 		spin_unlock_bh(&addrconf_hash_lock);
2943 	}
2944 
2945 	write_lock_bh(&idev->lock);
2946 
2947 	/* Step 2: clear flags for stateless addrconf */
2948 	if (!how)
2949 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
2950 
2951 #ifdef CONFIG_IPV6_PRIVACY
2952 	if (how && del_timer(&idev->regen_timer))
2953 		in6_dev_put(idev);
2954 
2955 	/* Step 3: clear tempaddr list */
2956 	while (!list_empty(&idev->tempaddr_list)) {
2957 		ifa = list_first_entry(&idev->tempaddr_list,
2958 				       struct inet6_ifaddr, tmp_list);
2959 		list_del(&ifa->tmp_list);
2960 		write_unlock_bh(&idev->lock);
2961 		spin_lock_bh(&ifa->lock);
2962 
2963 		if (ifa->ifpub) {
2964 			in6_ifa_put(ifa->ifpub);
2965 			ifa->ifpub = NULL;
2966 		}
2967 		spin_unlock_bh(&ifa->lock);
2968 		in6_ifa_put(ifa);
2969 		write_lock_bh(&idev->lock);
2970 	}
2971 #endif
2972 
2973 	while (!list_empty(&idev->addr_list)) {
2974 		ifa = list_first_entry(&idev->addr_list,
2975 				       struct inet6_ifaddr, if_list);
2976 		addrconf_del_timer(ifa);
2977 
2978 		list_del(&ifa->if_list);
2979 
2980 		write_unlock_bh(&idev->lock);
2981 
2982 		spin_lock_bh(&ifa->state_lock);
2983 		state = ifa->state;
2984 		ifa->state = INET6_IFADDR_STATE_DEAD;
2985 		spin_unlock_bh(&ifa->state_lock);
2986 
2987 		if (state != INET6_IFADDR_STATE_DEAD) {
2988 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
2989 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
2990 		}
2991 		in6_ifa_put(ifa);
2992 
2993 		write_lock_bh(&idev->lock);
2994 	}
2995 
2996 	write_unlock_bh(&idev->lock);
2997 
2998 	/* Step 5: Discard multicast list */
2999 	if (how)
3000 		ipv6_mc_destroy_dev(idev);
3001 	else
3002 		ipv6_mc_down(idev);
3003 
3004 	idev->tstamp = jiffies;
3005 
3006 	/* Last: Shot the device (if unregistered) */
3007 	if (how) {
3008 		addrconf_sysctl_unregister(idev);
3009 		neigh_parms_release(&nd_tbl, idev->nd_parms);
3010 		neigh_ifdown(&nd_tbl, dev);
3011 		in6_dev_put(idev);
3012 	}
3013 	return 0;
3014 }
3015 
3016 static void addrconf_rs_timer(unsigned long data)
3017 {
3018 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *) data;
3019 	struct inet6_dev *idev = ifp->idev;
3020 
3021 	read_lock(&idev->lock);
3022 	if (idev->dead || !(idev->if_flags & IF_READY))
3023 		goto out;
3024 
3025 	if (!ipv6_accept_ra(idev))
3026 		goto out;
3027 
3028 	/* Announcement received after solicitation was sent */
3029 	if (idev->if_flags & IF_RA_RCVD)
3030 		goto out;
3031 
3032 	spin_lock(&ifp->lock);
3033 	if (ifp->probes++ < idev->cnf.rtr_solicits) {
3034 		/* The wait after the last probe can be shorter */
3035 		addrconf_mod_timer(ifp, AC_RS,
3036 				   (ifp->probes == idev->cnf.rtr_solicits) ?
3037 				   idev->cnf.rtr_solicit_delay :
3038 				   idev->cnf.rtr_solicit_interval);
3039 		spin_unlock(&ifp->lock);
3040 
3041 		ndisc_send_rs(idev->dev, &ifp->addr, &in6addr_linklocal_allrouters);
3042 	} else {
3043 		spin_unlock(&ifp->lock);
3044 		/*
3045 		 * Note: we do not support deprecated "all on-link"
3046 		 * assumption any longer.
3047 		 */
3048 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
3049 	}
3050 
3051 out:
3052 	read_unlock(&idev->lock);
3053 	in6_ifa_put(ifp);
3054 }
3055 
3056 /*
3057  *	Duplicate Address Detection
3058  */
3059 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
3060 {
3061 	unsigned long rand_num;
3062 	struct inet6_dev *idev = ifp->idev;
3063 
3064 	if (ifp->flags & IFA_F_OPTIMISTIC)
3065 		rand_num = 0;
3066 	else
3067 		rand_num = net_random() % (idev->cnf.rtr_solicit_delay ? : 1);
3068 
3069 	ifp->probes = idev->cnf.dad_transmits;
3070 	addrconf_mod_timer(ifp, AC_DAD, rand_num);
3071 }
3072 
3073 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
3074 {
3075 	struct inet6_dev *idev = ifp->idev;
3076 	struct net_device *dev = idev->dev;
3077 
3078 	addrconf_join_solict(dev, &ifp->addr);
3079 
3080 	net_srandom(ifp->addr.s6_addr32[3]);
3081 
3082 	read_lock_bh(&idev->lock);
3083 	spin_lock(&ifp->lock);
3084 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
3085 		goto out;
3086 
3087 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
3088 	    idev->cnf.accept_dad < 1 ||
3089 	    !(ifp->flags&IFA_F_TENTATIVE) ||
3090 	    ifp->flags & IFA_F_NODAD) {
3091 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3092 		spin_unlock(&ifp->lock);
3093 		read_unlock_bh(&idev->lock);
3094 
3095 		addrconf_dad_completed(ifp);
3096 		return;
3097 	}
3098 
3099 	if (!(idev->if_flags & IF_READY)) {
3100 		spin_unlock(&ifp->lock);
3101 		read_unlock_bh(&idev->lock);
3102 		/*
3103 		 * If the device is not ready:
3104 		 * - keep it tentative if it is a permanent address.
3105 		 * - otherwise, kill it.
3106 		 */
3107 		in6_ifa_hold(ifp);
3108 		addrconf_dad_stop(ifp, 0);
3109 		return;
3110 	}
3111 
3112 	/*
3113 	 * Optimistic nodes can start receiving
3114 	 * Frames right away
3115 	 */
3116 	if (ifp->flags & IFA_F_OPTIMISTIC)
3117 		ip6_ins_rt(ifp->rt);
3118 
3119 	addrconf_dad_kick(ifp);
3120 out:
3121 	spin_unlock(&ifp->lock);
3122 	read_unlock_bh(&idev->lock);
3123 }
3124 
3125 static void addrconf_dad_timer(unsigned long data)
3126 {
3127 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *) data;
3128 	struct inet6_dev *idev = ifp->idev;
3129 	struct in6_addr mcaddr;
3130 
3131 	if (!ifp->probes && addrconf_dad_end(ifp))
3132 		goto out;
3133 
3134 	read_lock(&idev->lock);
3135 	if (idev->dead || !(idev->if_flags & IF_READY)) {
3136 		read_unlock(&idev->lock);
3137 		goto out;
3138 	}
3139 
3140 	spin_lock(&ifp->lock);
3141 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
3142 		spin_unlock(&ifp->lock);
3143 		read_unlock(&idev->lock);
3144 		goto out;
3145 	}
3146 
3147 	if (ifp->probes == 0) {
3148 		/*
3149 		 * DAD was successful
3150 		 */
3151 
3152 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3153 		spin_unlock(&ifp->lock);
3154 		read_unlock(&idev->lock);
3155 
3156 		addrconf_dad_completed(ifp);
3157 
3158 		goto out;
3159 	}
3160 
3161 	ifp->probes--;
3162 	addrconf_mod_timer(ifp, AC_DAD, ifp->idev->nd_parms->retrans_time);
3163 	spin_unlock(&ifp->lock);
3164 	read_unlock(&idev->lock);
3165 
3166 	/* send a neighbour solicitation for our addr */
3167 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
3168 	ndisc_send_ns(ifp->idev->dev, NULL, &ifp->addr, &mcaddr, &in6addr_any);
3169 out:
3170 	in6_ifa_put(ifp);
3171 }
3172 
3173 static void addrconf_dad_completed(struct inet6_ifaddr *ifp)
3174 {
3175 	struct net_device *dev = ifp->idev->dev;
3176 
3177 	/*
3178 	 *	Configure the address for reception. Now it is valid.
3179 	 */
3180 
3181 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
3182 
3183 	/* If added prefix is link local and we are prepared to process
3184 	   router advertisements, start sending router solicitations.
3185 	 */
3186 
3187 	if (ipv6_accept_ra(ifp->idev) &&
3188 	    ifp->idev->cnf.rtr_solicits > 0 &&
3189 	    (dev->flags&IFF_LOOPBACK) == 0 &&
3190 	    (ipv6_addr_type(&ifp->addr) & IPV6_ADDR_LINKLOCAL)) {
3191 		/*
3192 		 *	If a host as already performed a random delay
3193 		 *	[...] as part of DAD [...] there is no need
3194 		 *	to delay again before sending the first RS
3195 		 */
3196 		ndisc_send_rs(ifp->idev->dev, &ifp->addr, &in6addr_linklocal_allrouters);
3197 
3198 		spin_lock_bh(&ifp->lock);
3199 		ifp->probes = 1;
3200 		ifp->idev->if_flags |= IF_RS_SENT;
3201 		addrconf_mod_timer(ifp, AC_RS, ifp->idev->cnf.rtr_solicit_interval);
3202 		spin_unlock_bh(&ifp->lock);
3203 	}
3204 }
3205 
3206 static void addrconf_dad_run(struct inet6_dev *idev)
3207 {
3208 	struct inet6_ifaddr *ifp;
3209 
3210 	read_lock_bh(&idev->lock);
3211 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
3212 		spin_lock(&ifp->lock);
3213 		if (ifp->flags & IFA_F_TENTATIVE &&
3214 		    ifp->state == INET6_IFADDR_STATE_DAD)
3215 			addrconf_dad_kick(ifp);
3216 		spin_unlock(&ifp->lock);
3217 	}
3218 	read_unlock_bh(&idev->lock);
3219 }
3220 
3221 #ifdef CONFIG_PROC_FS
3222 struct if6_iter_state {
3223 	struct seq_net_private p;
3224 	int bucket;
3225 	int offset;
3226 };
3227 
3228 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
3229 {
3230 	struct inet6_ifaddr *ifa = NULL;
3231 	struct if6_iter_state *state = seq->private;
3232 	struct net *net = seq_file_net(seq);
3233 	int p = 0;
3234 
3235 	/* initial bucket if pos is 0 */
3236 	if (pos == 0) {
3237 		state->bucket = 0;
3238 		state->offset = 0;
3239 	}
3240 
3241 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
3242 		hlist_for_each_entry_rcu_bh(ifa, &inet6_addr_lst[state->bucket],
3243 					 addr_lst) {
3244 			if (!net_eq(dev_net(ifa->idev->dev), net))
3245 				continue;
3246 			/* sync with offset */
3247 			if (p < state->offset) {
3248 				p++;
3249 				continue;
3250 			}
3251 			state->offset++;
3252 			return ifa;
3253 		}
3254 
3255 		/* prepare for next bucket */
3256 		state->offset = 0;
3257 		p = 0;
3258 	}
3259 	return NULL;
3260 }
3261 
3262 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
3263 					 struct inet6_ifaddr *ifa)
3264 {
3265 	struct if6_iter_state *state = seq->private;
3266 	struct net *net = seq_file_net(seq);
3267 
3268 	hlist_for_each_entry_continue_rcu_bh(ifa, addr_lst) {
3269 		if (!net_eq(dev_net(ifa->idev->dev), net))
3270 			continue;
3271 		state->offset++;
3272 		return ifa;
3273 	}
3274 
3275 	while (++state->bucket < IN6_ADDR_HSIZE) {
3276 		state->offset = 0;
3277 		hlist_for_each_entry_rcu_bh(ifa,
3278 				     &inet6_addr_lst[state->bucket], addr_lst) {
3279 			if (!net_eq(dev_net(ifa->idev->dev), net))
3280 				continue;
3281 			state->offset++;
3282 			return ifa;
3283 		}
3284 	}
3285 
3286 	return NULL;
3287 }
3288 
3289 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
3290 	__acquires(rcu_bh)
3291 {
3292 	rcu_read_lock_bh();
3293 	return if6_get_first(seq, *pos);
3294 }
3295 
3296 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3297 {
3298 	struct inet6_ifaddr *ifa;
3299 
3300 	ifa = if6_get_next(seq, v);
3301 	++*pos;
3302 	return ifa;
3303 }
3304 
3305 static void if6_seq_stop(struct seq_file *seq, void *v)
3306 	__releases(rcu_bh)
3307 {
3308 	rcu_read_unlock_bh();
3309 }
3310 
3311 static int if6_seq_show(struct seq_file *seq, void *v)
3312 {
3313 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
3314 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
3315 		   &ifp->addr,
3316 		   ifp->idev->dev->ifindex,
3317 		   ifp->prefix_len,
3318 		   ifp->scope,
3319 		   ifp->flags,
3320 		   ifp->idev->dev->name);
3321 	return 0;
3322 }
3323 
3324 static const struct seq_operations if6_seq_ops = {
3325 	.start	= if6_seq_start,
3326 	.next	= if6_seq_next,
3327 	.show	= if6_seq_show,
3328 	.stop	= if6_seq_stop,
3329 };
3330 
3331 static int if6_seq_open(struct inode *inode, struct file *file)
3332 {
3333 	return seq_open_net(inode, file, &if6_seq_ops,
3334 			    sizeof(struct if6_iter_state));
3335 }
3336 
3337 static const struct file_operations if6_fops = {
3338 	.owner		= THIS_MODULE,
3339 	.open		= if6_seq_open,
3340 	.read		= seq_read,
3341 	.llseek		= seq_lseek,
3342 	.release	= seq_release_net,
3343 };
3344 
3345 static int __net_init if6_proc_net_init(struct net *net)
3346 {
3347 	if (!proc_create("if_inet6", S_IRUGO, net->proc_net, &if6_fops))
3348 		return -ENOMEM;
3349 	return 0;
3350 }
3351 
3352 static void __net_exit if6_proc_net_exit(struct net *net)
3353 {
3354 	remove_proc_entry("if_inet6", net->proc_net);
3355 }
3356 
3357 static struct pernet_operations if6_proc_net_ops = {
3358        .init = if6_proc_net_init,
3359        .exit = if6_proc_net_exit,
3360 };
3361 
3362 int __init if6_proc_init(void)
3363 {
3364 	return register_pernet_subsys(&if6_proc_net_ops);
3365 }
3366 
3367 void if6_proc_exit(void)
3368 {
3369 	unregister_pernet_subsys(&if6_proc_net_ops);
3370 }
3371 #endif	/* CONFIG_PROC_FS */
3372 
3373 #if IS_ENABLED(CONFIG_IPV6_MIP6)
3374 /* Check if address is a home address configured on any interface. */
3375 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
3376 {
3377 	int ret = 0;
3378 	struct inet6_ifaddr *ifp = NULL;
3379 	unsigned int hash = inet6_addr_hash(addr);
3380 
3381 	rcu_read_lock_bh();
3382 	hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[hash], addr_lst) {
3383 		if (!net_eq(dev_net(ifp->idev->dev), net))
3384 			continue;
3385 		if (ipv6_addr_equal(&ifp->addr, addr) &&
3386 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
3387 			ret = 1;
3388 			break;
3389 		}
3390 	}
3391 	rcu_read_unlock_bh();
3392 	return ret;
3393 }
3394 #endif
3395 
3396 /*
3397  *	Periodic address status verification
3398  */
3399 
3400 static void addrconf_verify(unsigned long foo)
3401 {
3402 	unsigned long now, next, next_sec, next_sched;
3403 	struct inet6_ifaddr *ifp;
3404 	int i;
3405 
3406 	rcu_read_lock_bh();
3407 	spin_lock(&addrconf_verify_lock);
3408 	now = jiffies;
3409 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
3410 
3411 	del_timer(&addr_chk_timer);
3412 
3413 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3414 restart:
3415 		hlist_for_each_entry_rcu_bh(ifp,
3416 					 &inet6_addr_lst[i], addr_lst) {
3417 			unsigned long age;
3418 
3419 			if (ifp->flags & IFA_F_PERMANENT)
3420 				continue;
3421 
3422 			spin_lock(&ifp->lock);
3423 			/* We try to batch several events at once. */
3424 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
3425 
3426 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
3427 			    age >= ifp->valid_lft) {
3428 				spin_unlock(&ifp->lock);
3429 				in6_ifa_hold(ifp);
3430 				ipv6_del_addr(ifp);
3431 				goto restart;
3432 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
3433 				spin_unlock(&ifp->lock);
3434 				continue;
3435 			} else if (age >= ifp->prefered_lft) {
3436 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
3437 				int deprecate = 0;
3438 
3439 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
3440 					deprecate = 1;
3441 					ifp->flags |= IFA_F_DEPRECATED;
3442 				}
3443 
3444 				if (time_before(ifp->tstamp + ifp->valid_lft * HZ, next))
3445 					next = ifp->tstamp + ifp->valid_lft * HZ;
3446 
3447 				spin_unlock(&ifp->lock);
3448 
3449 				if (deprecate) {
3450 					in6_ifa_hold(ifp);
3451 
3452 					ipv6_ifa_notify(0, ifp);
3453 					in6_ifa_put(ifp);
3454 					goto restart;
3455 				}
3456 #ifdef CONFIG_IPV6_PRIVACY
3457 			} else if ((ifp->flags&IFA_F_TEMPORARY) &&
3458 				   !(ifp->flags&IFA_F_TENTATIVE)) {
3459 				unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
3460 					ifp->idev->cnf.dad_transmits *
3461 					ifp->idev->nd_parms->retrans_time / HZ;
3462 
3463 				if (age >= ifp->prefered_lft - regen_advance) {
3464 					struct inet6_ifaddr *ifpub = ifp->ifpub;
3465 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
3466 						next = ifp->tstamp + ifp->prefered_lft * HZ;
3467 					if (!ifp->regen_count && ifpub) {
3468 						ifp->regen_count++;
3469 						in6_ifa_hold(ifp);
3470 						in6_ifa_hold(ifpub);
3471 						spin_unlock(&ifp->lock);
3472 
3473 						spin_lock(&ifpub->lock);
3474 						ifpub->regen_count = 0;
3475 						spin_unlock(&ifpub->lock);
3476 						ipv6_create_tempaddr(ifpub, ifp);
3477 						in6_ifa_put(ifpub);
3478 						in6_ifa_put(ifp);
3479 						goto restart;
3480 					}
3481 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
3482 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
3483 				spin_unlock(&ifp->lock);
3484 #endif
3485 			} else {
3486 				/* ifp->prefered_lft <= ifp->valid_lft */
3487 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
3488 					next = ifp->tstamp + ifp->prefered_lft * HZ;
3489 				spin_unlock(&ifp->lock);
3490 			}
3491 		}
3492 	}
3493 
3494 	next_sec = round_jiffies_up(next);
3495 	next_sched = next;
3496 
3497 	/* If rounded timeout is accurate enough, accept it. */
3498 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
3499 		next_sched = next_sec;
3500 
3501 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
3502 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
3503 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
3504 
3505 	ADBG((KERN_DEBUG "now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
3506 	      now, next, next_sec, next_sched));
3507 
3508 	addr_chk_timer.expires = next_sched;
3509 	add_timer(&addr_chk_timer);
3510 	spin_unlock(&addrconf_verify_lock);
3511 	rcu_read_unlock_bh();
3512 }
3513 
3514 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local)
3515 {
3516 	struct in6_addr *pfx = NULL;
3517 
3518 	if (addr)
3519 		pfx = nla_data(addr);
3520 
3521 	if (local) {
3522 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
3523 			pfx = NULL;
3524 		else
3525 			pfx = nla_data(local);
3526 	}
3527 
3528 	return pfx;
3529 }
3530 
3531 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
3532 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
3533 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
3534 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
3535 };
3536 
3537 static int
3538 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
3539 {
3540 	struct net *net = sock_net(skb->sk);
3541 	struct ifaddrmsg *ifm;
3542 	struct nlattr *tb[IFA_MAX+1];
3543 	struct in6_addr *pfx;
3544 	int err;
3545 
3546 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
3547 	if (err < 0)
3548 		return err;
3549 
3550 	ifm = nlmsg_data(nlh);
3551 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL]);
3552 	if (pfx == NULL)
3553 		return -EINVAL;
3554 
3555 	return inet6_addr_del(net, ifm->ifa_index, pfx, ifm->ifa_prefixlen);
3556 }
3557 
3558 static int inet6_addr_modify(struct inet6_ifaddr *ifp, u8 ifa_flags,
3559 			     u32 prefered_lft, u32 valid_lft)
3560 {
3561 	u32 flags;
3562 	clock_t expires;
3563 	unsigned long timeout;
3564 
3565 	if (!valid_lft || (prefered_lft > valid_lft))
3566 		return -EINVAL;
3567 
3568 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
3569 	if (addrconf_finite_timeout(timeout)) {
3570 		expires = jiffies_to_clock_t(timeout * HZ);
3571 		valid_lft = timeout;
3572 		flags = RTF_EXPIRES;
3573 	} else {
3574 		expires = 0;
3575 		flags = 0;
3576 		ifa_flags |= IFA_F_PERMANENT;
3577 	}
3578 
3579 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
3580 	if (addrconf_finite_timeout(timeout)) {
3581 		if (timeout == 0)
3582 			ifa_flags |= IFA_F_DEPRECATED;
3583 		prefered_lft = timeout;
3584 	}
3585 
3586 	spin_lock_bh(&ifp->lock);
3587 	ifp->flags = (ifp->flags & ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD | IFA_F_HOMEADDRESS)) | ifa_flags;
3588 	ifp->tstamp = jiffies;
3589 	ifp->valid_lft = valid_lft;
3590 	ifp->prefered_lft = prefered_lft;
3591 
3592 	spin_unlock_bh(&ifp->lock);
3593 	if (!(ifp->flags&IFA_F_TENTATIVE))
3594 		ipv6_ifa_notify(0, ifp);
3595 
3596 	addrconf_prefix_route(&ifp->addr, ifp->prefix_len, ifp->idev->dev,
3597 			      expires, flags);
3598 	addrconf_verify(0);
3599 
3600 	return 0;
3601 }
3602 
3603 static int
3604 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
3605 {
3606 	struct net *net = sock_net(skb->sk);
3607 	struct ifaddrmsg *ifm;
3608 	struct nlattr *tb[IFA_MAX+1];
3609 	struct in6_addr *pfx;
3610 	struct inet6_ifaddr *ifa;
3611 	struct net_device *dev;
3612 	u32 valid_lft = INFINITY_LIFE_TIME, preferred_lft = INFINITY_LIFE_TIME;
3613 	u8 ifa_flags;
3614 	int err;
3615 
3616 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
3617 	if (err < 0)
3618 		return err;
3619 
3620 	ifm = nlmsg_data(nlh);
3621 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL]);
3622 	if (pfx == NULL)
3623 		return -EINVAL;
3624 
3625 	if (tb[IFA_CACHEINFO]) {
3626 		struct ifa_cacheinfo *ci;
3627 
3628 		ci = nla_data(tb[IFA_CACHEINFO]);
3629 		valid_lft = ci->ifa_valid;
3630 		preferred_lft = ci->ifa_prefered;
3631 	} else {
3632 		preferred_lft = INFINITY_LIFE_TIME;
3633 		valid_lft = INFINITY_LIFE_TIME;
3634 	}
3635 
3636 	dev =  __dev_get_by_index(net, ifm->ifa_index);
3637 	if (dev == NULL)
3638 		return -ENODEV;
3639 
3640 	/* We ignore other flags so far. */
3641 	ifa_flags = ifm->ifa_flags & (IFA_F_NODAD | IFA_F_HOMEADDRESS);
3642 
3643 	ifa = ipv6_get_ifaddr(net, pfx, dev, 1);
3644 	if (ifa == NULL) {
3645 		/*
3646 		 * It would be best to check for !NLM_F_CREATE here but
3647 		 * userspace alreay relies on not having to provide this.
3648 		 */
3649 		return inet6_addr_add(net, ifm->ifa_index, pfx,
3650 				      ifm->ifa_prefixlen, ifa_flags,
3651 				      preferred_lft, valid_lft);
3652 	}
3653 
3654 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
3655 	    !(nlh->nlmsg_flags & NLM_F_REPLACE))
3656 		err = -EEXIST;
3657 	else
3658 		err = inet6_addr_modify(ifa, ifa_flags, preferred_lft, valid_lft);
3659 
3660 	in6_ifa_put(ifa);
3661 
3662 	return err;
3663 }
3664 
3665 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u8 flags,
3666 			  u8 scope, int ifindex)
3667 {
3668 	struct ifaddrmsg *ifm;
3669 
3670 	ifm = nlmsg_data(nlh);
3671 	ifm->ifa_family = AF_INET6;
3672 	ifm->ifa_prefixlen = prefixlen;
3673 	ifm->ifa_flags = flags;
3674 	ifm->ifa_scope = scope;
3675 	ifm->ifa_index = ifindex;
3676 }
3677 
3678 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
3679 			 unsigned long tstamp, u32 preferred, u32 valid)
3680 {
3681 	struct ifa_cacheinfo ci;
3682 
3683 	ci.cstamp = cstamp_delta(cstamp);
3684 	ci.tstamp = cstamp_delta(tstamp);
3685 	ci.ifa_prefered = preferred;
3686 	ci.ifa_valid = valid;
3687 
3688 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
3689 }
3690 
3691 static inline int rt_scope(int ifa_scope)
3692 {
3693 	if (ifa_scope & IFA_HOST)
3694 		return RT_SCOPE_HOST;
3695 	else if (ifa_scope & IFA_LINK)
3696 		return RT_SCOPE_LINK;
3697 	else if (ifa_scope & IFA_SITE)
3698 		return RT_SCOPE_SITE;
3699 	else
3700 		return RT_SCOPE_UNIVERSE;
3701 }
3702 
3703 static inline int inet6_ifaddr_msgsize(void)
3704 {
3705 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
3706 	       + nla_total_size(16) /* IFA_ADDRESS */
3707 	       + nla_total_size(sizeof(struct ifa_cacheinfo));
3708 }
3709 
3710 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
3711 			     u32 portid, u32 seq, int event, unsigned int flags)
3712 {
3713 	struct nlmsghdr  *nlh;
3714 	u32 preferred, valid;
3715 
3716 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
3717 	if (nlh == NULL)
3718 		return -EMSGSIZE;
3719 
3720 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
3721 		      ifa->idev->dev->ifindex);
3722 
3723 	if (!(ifa->flags&IFA_F_PERMANENT)) {
3724 		preferred = ifa->prefered_lft;
3725 		valid = ifa->valid_lft;
3726 		if (preferred != INFINITY_LIFE_TIME) {
3727 			long tval = (jiffies - ifa->tstamp)/HZ;
3728 			if (preferred > tval)
3729 				preferred -= tval;
3730 			else
3731 				preferred = 0;
3732 			if (valid != INFINITY_LIFE_TIME) {
3733 				if (valid > tval)
3734 					valid -= tval;
3735 				else
3736 					valid = 0;
3737 			}
3738 		}
3739 	} else {
3740 		preferred = INFINITY_LIFE_TIME;
3741 		valid = INFINITY_LIFE_TIME;
3742 	}
3743 
3744 	if (nla_put(skb, IFA_ADDRESS, 16, &ifa->addr) < 0 ||
3745 	    put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0) {
3746 		nlmsg_cancel(skb, nlh);
3747 		return -EMSGSIZE;
3748 	}
3749 
3750 	return nlmsg_end(skb, nlh);
3751 }
3752 
3753 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
3754 				u32 portid, u32 seq, int event, u16 flags)
3755 {
3756 	struct nlmsghdr  *nlh;
3757 	u8 scope = RT_SCOPE_UNIVERSE;
3758 	int ifindex = ifmca->idev->dev->ifindex;
3759 
3760 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
3761 		scope = RT_SCOPE_SITE;
3762 
3763 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
3764 	if (nlh == NULL)
3765 		return -EMSGSIZE;
3766 
3767 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
3768 	if (nla_put(skb, IFA_MULTICAST, 16, &ifmca->mca_addr) < 0 ||
3769 	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
3770 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
3771 		nlmsg_cancel(skb, nlh);
3772 		return -EMSGSIZE;
3773 	}
3774 
3775 	return nlmsg_end(skb, nlh);
3776 }
3777 
3778 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
3779 				u32 portid, u32 seq, int event, unsigned int flags)
3780 {
3781 	struct nlmsghdr  *nlh;
3782 	u8 scope = RT_SCOPE_UNIVERSE;
3783 	int ifindex = ifaca->aca_idev->dev->ifindex;
3784 
3785 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
3786 		scope = RT_SCOPE_SITE;
3787 
3788 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
3789 	if (nlh == NULL)
3790 		return -EMSGSIZE;
3791 
3792 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
3793 	if (nla_put(skb, IFA_ANYCAST, 16, &ifaca->aca_addr) < 0 ||
3794 	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
3795 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
3796 		nlmsg_cancel(skb, nlh);
3797 		return -EMSGSIZE;
3798 	}
3799 
3800 	return nlmsg_end(skb, nlh);
3801 }
3802 
3803 enum addr_type_t {
3804 	UNICAST_ADDR,
3805 	MULTICAST_ADDR,
3806 	ANYCAST_ADDR,
3807 };
3808 
3809 /* called with rcu_read_lock() */
3810 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
3811 			  struct netlink_callback *cb, enum addr_type_t type,
3812 			  int s_ip_idx, int *p_ip_idx)
3813 {
3814 	struct ifmcaddr6 *ifmca;
3815 	struct ifacaddr6 *ifaca;
3816 	int err = 1;
3817 	int ip_idx = *p_ip_idx;
3818 
3819 	read_lock_bh(&idev->lock);
3820 	switch (type) {
3821 	case UNICAST_ADDR: {
3822 		struct inet6_ifaddr *ifa;
3823 
3824 		/* unicast address incl. temp addr */
3825 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
3826 			if (++ip_idx < s_ip_idx)
3827 				continue;
3828 			err = inet6_fill_ifaddr(skb, ifa,
3829 						NETLINK_CB(cb->skb).portid,
3830 						cb->nlh->nlmsg_seq,
3831 						RTM_NEWADDR,
3832 						NLM_F_MULTI);
3833 			if (err <= 0)
3834 				break;
3835 		}
3836 		break;
3837 	}
3838 	case MULTICAST_ADDR:
3839 		/* multicast address */
3840 		for (ifmca = idev->mc_list; ifmca;
3841 		     ifmca = ifmca->next, ip_idx++) {
3842 			if (ip_idx < s_ip_idx)
3843 				continue;
3844 			err = inet6_fill_ifmcaddr(skb, ifmca,
3845 						  NETLINK_CB(cb->skb).portid,
3846 						  cb->nlh->nlmsg_seq,
3847 						  RTM_GETMULTICAST,
3848 						  NLM_F_MULTI);
3849 			if (err <= 0)
3850 				break;
3851 		}
3852 		break;
3853 	case ANYCAST_ADDR:
3854 		/* anycast address */
3855 		for (ifaca = idev->ac_list; ifaca;
3856 		     ifaca = ifaca->aca_next, ip_idx++) {
3857 			if (ip_idx < s_ip_idx)
3858 				continue;
3859 			err = inet6_fill_ifacaddr(skb, ifaca,
3860 						  NETLINK_CB(cb->skb).portid,
3861 						  cb->nlh->nlmsg_seq,
3862 						  RTM_GETANYCAST,
3863 						  NLM_F_MULTI);
3864 			if (err <= 0)
3865 				break;
3866 		}
3867 		break;
3868 	default:
3869 		break;
3870 	}
3871 	read_unlock_bh(&idev->lock);
3872 	*p_ip_idx = ip_idx;
3873 	return err;
3874 }
3875 
3876 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
3877 			   enum addr_type_t type)
3878 {
3879 	struct net *net = sock_net(skb->sk);
3880 	int h, s_h;
3881 	int idx, ip_idx;
3882 	int s_idx, s_ip_idx;
3883 	struct net_device *dev;
3884 	struct inet6_dev *idev;
3885 	struct hlist_head *head;
3886 
3887 	s_h = cb->args[0];
3888 	s_idx = idx = cb->args[1];
3889 	s_ip_idx = ip_idx = cb->args[2];
3890 
3891 	rcu_read_lock();
3892 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
3893 		idx = 0;
3894 		head = &net->dev_index_head[h];
3895 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
3896 			if (idx < s_idx)
3897 				goto cont;
3898 			if (h > s_h || idx > s_idx)
3899 				s_ip_idx = 0;
3900 			ip_idx = 0;
3901 			idev = __in6_dev_get(dev);
3902 			if (!idev)
3903 				goto cont;
3904 
3905 			if (in6_dump_addrs(idev, skb, cb, type,
3906 					   s_ip_idx, &ip_idx) <= 0)
3907 				goto done;
3908 cont:
3909 			idx++;
3910 		}
3911 	}
3912 done:
3913 	rcu_read_unlock();
3914 	cb->args[0] = h;
3915 	cb->args[1] = idx;
3916 	cb->args[2] = ip_idx;
3917 
3918 	return skb->len;
3919 }
3920 
3921 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
3922 {
3923 	enum addr_type_t type = UNICAST_ADDR;
3924 
3925 	return inet6_dump_addr(skb, cb, type);
3926 }
3927 
3928 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
3929 {
3930 	enum addr_type_t type = MULTICAST_ADDR;
3931 
3932 	return inet6_dump_addr(skb, cb, type);
3933 }
3934 
3935 
3936 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
3937 {
3938 	enum addr_type_t type = ANYCAST_ADDR;
3939 
3940 	return inet6_dump_addr(skb, cb, type);
3941 }
3942 
3943 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
3944 			     void *arg)
3945 {
3946 	struct net *net = sock_net(in_skb->sk);
3947 	struct ifaddrmsg *ifm;
3948 	struct nlattr *tb[IFA_MAX+1];
3949 	struct in6_addr *addr = NULL;
3950 	struct net_device *dev = NULL;
3951 	struct inet6_ifaddr *ifa;
3952 	struct sk_buff *skb;
3953 	int err;
3954 
3955 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
3956 	if (err < 0)
3957 		goto errout;
3958 
3959 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL]);
3960 	if (addr == NULL) {
3961 		err = -EINVAL;
3962 		goto errout;
3963 	}
3964 
3965 	ifm = nlmsg_data(nlh);
3966 	if (ifm->ifa_index)
3967 		dev = __dev_get_by_index(net, ifm->ifa_index);
3968 
3969 	ifa = ipv6_get_ifaddr(net, addr, dev, 1);
3970 	if (!ifa) {
3971 		err = -EADDRNOTAVAIL;
3972 		goto errout;
3973 	}
3974 
3975 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
3976 	if (!skb) {
3977 		err = -ENOBUFS;
3978 		goto errout_ifa;
3979 	}
3980 
3981 	err = inet6_fill_ifaddr(skb, ifa, NETLINK_CB(in_skb).portid,
3982 				nlh->nlmsg_seq, RTM_NEWADDR, 0);
3983 	if (err < 0) {
3984 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
3985 		WARN_ON(err == -EMSGSIZE);
3986 		kfree_skb(skb);
3987 		goto errout_ifa;
3988 	}
3989 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
3990 errout_ifa:
3991 	in6_ifa_put(ifa);
3992 errout:
3993 	return err;
3994 }
3995 
3996 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
3997 {
3998 	struct sk_buff *skb;
3999 	struct net *net = dev_net(ifa->idev->dev);
4000 	int err = -ENOBUFS;
4001 
4002 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
4003 	if (skb == NULL)
4004 		goto errout;
4005 
4006 	err = inet6_fill_ifaddr(skb, ifa, 0, 0, event, 0);
4007 	if (err < 0) {
4008 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
4009 		WARN_ON(err == -EMSGSIZE);
4010 		kfree_skb(skb);
4011 		goto errout;
4012 	}
4013 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
4014 	return;
4015 errout:
4016 	if (err < 0)
4017 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
4018 }
4019 
4020 static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
4021 				__s32 *array, int bytes)
4022 {
4023 	BUG_ON(bytes < (DEVCONF_MAX * 4));
4024 
4025 	memset(array, 0, bytes);
4026 	array[DEVCONF_FORWARDING] = cnf->forwarding;
4027 	array[DEVCONF_HOPLIMIT] = cnf->hop_limit;
4028 	array[DEVCONF_MTU6] = cnf->mtu6;
4029 	array[DEVCONF_ACCEPT_RA] = cnf->accept_ra;
4030 	array[DEVCONF_ACCEPT_REDIRECTS] = cnf->accept_redirects;
4031 	array[DEVCONF_AUTOCONF] = cnf->autoconf;
4032 	array[DEVCONF_DAD_TRANSMITS] = cnf->dad_transmits;
4033 	array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
4034 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
4035 		jiffies_to_msecs(cnf->rtr_solicit_interval);
4036 	array[DEVCONF_RTR_SOLICIT_DELAY] =
4037 		jiffies_to_msecs(cnf->rtr_solicit_delay);
4038 	array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;
4039 #ifdef CONFIG_IPV6_PRIVACY
4040 	array[DEVCONF_USE_TEMPADDR] = cnf->use_tempaddr;
4041 	array[DEVCONF_TEMP_VALID_LFT] = cnf->temp_valid_lft;
4042 	array[DEVCONF_TEMP_PREFERED_LFT] = cnf->temp_prefered_lft;
4043 	array[DEVCONF_REGEN_MAX_RETRY] = cnf->regen_max_retry;
4044 	array[DEVCONF_MAX_DESYNC_FACTOR] = cnf->max_desync_factor;
4045 #endif
4046 	array[DEVCONF_MAX_ADDRESSES] = cnf->max_addresses;
4047 	array[DEVCONF_ACCEPT_RA_DEFRTR] = cnf->accept_ra_defrtr;
4048 	array[DEVCONF_ACCEPT_RA_PINFO] = cnf->accept_ra_pinfo;
4049 #ifdef CONFIG_IPV6_ROUTER_PREF
4050 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = cnf->accept_ra_rtr_pref;
4051 	array[DEVCONF_RTR_PROBE_INTERVAL] =
4052 		jiffies_to_msecs(cnf->rtr_probe_interval);
4053 #ifdef CONFIG_IPV6_ROUTE_INFO
4054 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
4055 #endif
4056 #endif
4057 	array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
4058 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
4059 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
4060 	array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
4061 #endif
4062 #ifdef CONFIG_IPV6_MROUTE
4063 	array[DEVCONF_MC_FORWARDING] = cnf->mc_forwarding;
4064 #endif
4065 	array[DEVCONF_DISABLE_IPV6] = cnf->disable_ipv6;
4066 	array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad;
4067 	array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao;
4068 	array[DEVCONF_NDISC_NOTIFY] = cnf->ndisc_notify;
4069 }
4070 
4071 static inline size_t inet6_ifla6_size(void)
4072 {
4073 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
4074 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
4075 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
4076 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
4077 	     + nla_total_size(ICMP6_MIB_MAX * 8); /* IFLA_INET6_ICMP6STATS */
4078 }
4079 
4080 static inline size_t inet6_if_nlmsg_size(void)
4081 {
4082 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
4083 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
4084 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
4085 	       + nla_total_size(4) /* IFLA_MTU */
4086 	       + nla_total_size(4) /* IFLA_LINK */
4087 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
4088 }
4089 
4090 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
4091 				      int items, int bytes)
4092 {
4093 	int i;
4094 	int pad = bytes - sizeof(u64) * items;
4095 	BUG_ON(pad < 0);
4096 
4097 	/* Use put_unaligned() because stats may not be aligned for u64. */
4098 	put_unaligned(items, &stats[0]);
4099 	for (i = 1; i < items; i++)
4100 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
4101 
4102 	memset(&stats[items], 0, pad);
4103 }
4104 
4105 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu **mib,
4106 				      int items, int bytes, size_t syncpoff)
4107 {
4108 	int i;
4109 	int pad = bytes - sizeof(u64) * items;
4110 	BUG_ON(pad < 0);
4111 
4112 	/* Use put_unaligned() because stats may not be aligned for u64. */
4113 	put_unaligned(items, &stats[0]);
4114 	for (i = 1; i < items; i++)
4115 		put_unaligned(snmp_fold_field64(mib, i, syncpoff), &stats[i]);
4116 
4117 	memset(&stats[items], 0, pad);
4118 }
4119 
4120 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
4121 			     int bytes)
4122 {
4123 	switch (attrtype) {
4124 	case IFLA_INET6_STATS:
4125 		__snmp6_fill_stats64(stats, (void __percpu **)idev->stats.ipv6,
4126 				     IPSTATS_MIB_MAX, bytes, offsetof(struct ipstats_mib, syncp));
4127 		break;
4128 	case IFLA_INET6_ICMP6STATS:
4129 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, ICMP6_MIB_MAX, bytes);
4130 		break;
4131 	}
4132 }
4133 
4134 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev)
4135 {
4136 	struct nlattr *nla;
4137 	struct ifla_cacheinfo ci;
4138 
4139 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, idev->if_flags))
4140 		goto nla_put_failure;
4141 	ci.max_reasm_len = IPV6_MAXPLEN;
4142 	ci.tstamp = cstamp_delta(idev->tstamp);
4143 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
4144 	ci.retrans_time = jiffies_to_msecs(idev->nd_parms->retrans_time);
4145 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
4146 		goto nla_put_failure;
4147 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
4148 	if (nla == NULL)
4149 		goto nla_put_failure;
4150 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
4151 
4152 	/* XXX - MC not implemented */
4153 
4154 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
4155 	if (nla == NULL)
4156 		goto nla_put_failure;
4157 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
4158 
4159 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
4160 	if (nla == NULL)
4161 		goto nla_put_failure;
4162 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
4163 
4164 	return 0;
4165 
4166 nla_put_failure:
4167 	return -EMSGSIZE;
4168 }
4169 
4170 static size_t inet6_get_link_af_size(const struct net_device *dev)
4171 {
4172 	if (!__in6_dev_get(dev))
4173 		return 0;
4174 
4175 	return inet6_ifla6_size();
4176 }
4177 
4178 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev)
4179 {
4180 	struct inet6_dev *idev = __in6_dev_get(dev);
4181 
4182 	if (!idev)
4183 		return -ENODATA;
4184 
4185 	if (inet6_fill_ifla6_attrs(skb, idev) < 0)
4186 		return -EMSGSIZE;
4187 
4188 	return 0;
4189 }
4190 
4191 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
4192 			     u32 portid, u32 seq, int event, unsigned int flags)
4193 {
4194 	struct net_device *dev = idev->dev;
4195 	struct ifinfomsg *hdr;
4196 	struct nlmsghdr *nlh;
4197 	void *protoinfo;
4198 
4199 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
4200 	if (nlh == NULL)
4201 		return -EMSGSIZE;
4202 
4203 	hdr = nlmsg_data(nlh);
4204 	hdr->ifi_family = AF_INET6;
4205 	hdr->__ifi_pad = 0;
4206 	hdr->ifi_type = dev->type;
4207 	hdr->ifi_index = dev->ifindex;
4208 	hdr->ifi_flags = dev_get_flags(dev);
4209 	hdr->ifi_change = 0;
4210 
4211 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
4212 	    (dev->addr_len &&
4213 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
4214 	    nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
4215 	    (dev->ifindex != dev->iflink &&
4216 	     nla_put_u32(skb, IFLA_LINK, dev->iflink)))
4217 		goto nla_put_failure;
4218 	protoinfo = nla_nest_start(skb, IFLA_PROTINFO);
4219 	if (protoinfo == NULL)
4220 		goto nla_put_failure;
4221 
4222 	if (inet6_fill_ifla6_attrs(skb, idev) < 0)
4223 		goto nla_put_failure;
4224 
4225 	nla_nest_end(skb, protoinfo);
4226 	return nlmsg_end(skb, nlh);
4227 
4228 nla_put_failure:
4229 	nlmsg_cancel(skb, nlh);
4230 	return -EMSGSIZE;
4231 }
4232 
4233 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
4234 {
4235 	struct net *net = sock_net(skb->sk);
4236 	int h, s_h;
4237 	int idx = 0, s_idx;
4238 	struct net_device *dev;
4239 	struct inet6_dev *idev;
4240 	struct hlist_head *head;
4241 
4242 	s_h = cb->args[0];
4243 	s_idx = cb->args[1];
4244 
4245 	rcu_read_lock();
4246 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
4247 		idx = 0;
4248 		head = &net->dev_index_head[h];
4249 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
4250 			if (idx < s_idx)
4251 				goto cont;
4252 			idev = __in6_dev_get(dev);
4253 			if (!idev)
4254 				goto cont;
4255 			if (inet6_fill_ifinfo(skb, idev,
4256 					      NETLINK_CB(cb->skb).portid,
4257 					      cb->nlh->nlmsg_seq,
4258 					      RTM_NEWLINK, NLM_F_MULTI) <= 0)
4259 				goto out;
4260 cont:
4261 			idx++;
4262 		}
4263 	}
4264 out:
4265 	rcu_read_unlock();
4266 	cb->args[1] = idx;
4267 	cb->args[0] = h;
4268 
4269 	return skb->len;
4270 }
4271 
4272 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
4273 {
4274 	struct sk_buff *skb;
4275 	struct net *net = dev_net(idev->dev);
4276 	int err = -ENOBUFS;
4277 
4278 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
4279 	if (skb == NULL)
4280 		goto errout;
4281 
4282 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
4283 	if (err < 0) {
4284 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
4285 		WARN_ON(err == -EMSGSIZE);
4286 		kfree_skb(skb);
4287 		goto errout;
4288 	}
4289 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
4290 	return;
4291 errout:
4292 	if (err < 0)
4293 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
4294 }
4295 
4296 static inline size_t inet6_prefix_nlmsg_size(void)
4297 {
4298 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
4299 	       + nla_total_size(sizeof(struct in6_addr))
4300 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
4301 }
4302 
4303 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
4304 			     struct prefix_info *pinfo, u32 portid, u32 seq,
4305 			     int event, unsigned int flags)
4306 {
4307 	struct prefixmsg *pmsg;
4308 	struct nlmsghdr *nlh;
4309 	struct prefix_cacheinfo	ci;
4310 
4311 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
4312 	if (nlh == NULL)
4313 		return -EMSGSIZE;
4314 
4315 	pmsg = nlmsg_data(nlh);
4316 	pmsg->prefix_family = AF_INET6;
4317 	pmsg->prefix_pad1 = 0;
4318 	pmsg->prefix_pad2 = 0;
4319 	pmsg->prefix_ifindex = idev->dev->ifindex;
4320 	pmsg->prefix_len = pinfo->prefix_len;
4321 	pmsg->prefix_type = pinfo->type;
4322 	pmsg->prefix_pad3 = 0;
4323 	pmsg->prefix_flags = 0;
4324 	if (pinfo->onlink)
4325 		pmsg->prefix_flags |= IF_PREFIX_ONLINK;
4326 	if (pinfo->autoconf)
4327 		pmsg->prefix_flags |= IF_PREFIX_AUTOCONF;
4328 
4329 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
4330 		goto nla_put_failure;
4331 	ci.preferred_time = ntohl(pinfo->prefered);
4332 	ci.valid_time = ntohl(pinfo->valid);
4333 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
4334 		goto nla_put_failure;
4335 	return nlmsg_end(skb, nlh);
4336 
4337 nla_put_failure:
4338 	nlmsg_cancel(skb, nlh);
4339 	return -EMSGSIZE;
4340 }
4341 
4342 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
4343 			 struct prefix_info *pinfo)
4344 {
4345 	struct sk_buff *skb;
4346 	struct net *net = dev_net(idev->dev);
4347 	int err = -ENOBUFS;
4348 
4349 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
4350 	if (skb == NULL)
4351 		goto errout;
4352 
4353 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
4354 	if (err < 0) {
4355 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
4356 		WARN_ON(err == -EMSGSIZE);
4357 		kfree_skb(skb);
4358 		goto errout;
4359 	}
4360 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
4361 	return;
4362 errout:
4363 	if (err < 0)
4364 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
4365 }
4366 
4367 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
4368 {
4369 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
4370 
4371 	switch (event) {
4372 	case RTM_NEWADDR:
4373 		/*
4374 		 * If the address was optimistic
4375 		 * we inserted the route at the start of
4376 		 * our DAD process, so we don't need
4377 		 * to do it again
4378 		 */
4379 		if (!(ifp->rt->rt6i_node))
4380 			ip6_ins_rt(ifp->rt);
4381 		if (ifp->idev->cnf.forwarding)
4382 			addrconf_join_anycast(ifp);
4383 		break;
4384 	case RTM_DELADDR:
4385 		if (ifp->idev->cnf.forwarding)
4386 			addrconf_leave_anycast(ifp);
4387 		addrconf_leave_solict(ifp->idev, &ifp->addr);
4388 		dst_hold(&ifp->rt->dst);
4389 
4390 		if (ip6_del_rt(ifp->rt))
4391 			dst_free(&ifp->rt->dst);
4392 		break;
4393 	}
4394 }
4395 
4396 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
4397 {
4398 	rcu_read_lock_bh();
4399 	if (likely(ifp->idev->dead == 0))
4400 		__ipv6_ifa_notify(event, ifp);
4401 	rcu_read_unlock_bh();
4402 }
4403 
4404 #ifdef CONFIG_SYSCTL
4405 
4406 static
4407 int addrconf_sysctl_forward(ctl_table *ctl, int write,
4408 			   void __user *buffer, size_t *lenp, loff_t *ppos)
4409 {
4410 	int *valp = ctl->data;
4411 	int val = *valp;
4412 	loff_t pos = *ppos;
4413 	ctl_table lctl;
4414 	int ret;
4415 
4416 	/*
4417 	 * ctl->data points to idev->cnf.forwarding, we should
4418 	 * not modify it until we get the rtnl lock.
4419 	 */
4420 	lctl = *ctl;
4421 	lctl.data = &val;
4422 
4423 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
4424 
4425 	if (write)
4426 		ret = addrconf_fixup_forwarding(ctl, valp, val);
4427 	if (ret)
4428 		*ppos = pos;
4429 	return ret;
4430 }
4431 
4432 static void dev_disable_change(struct inet6_dev *idev)
4433 {
4434 	if (!idev || !idev->dev)
4435 		return;
4436 
4437 	if (idev->cnf.disable_ipv6)
4438 		addrconf_notify(NULL, NETDEV_DOWN, idev->dev);
4439 	else
4440 		addrconf_notify(NULL, NETDEV_UP, idev->dev);
4441 }
4442 
4443 static void addrconf_disable_change(struct net *net, __s32 newf)
4444 {
4445 	struct net_device *dev;
4446 	struct inet6_dev *idev;
4447 
4448 	rcu_read_lock();
4449 	for_each_netdev_rcu(net, dev) {
4450 		idev = __in6_dev_get(dev);
4451 		if (idev) {
4452 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
4453 			idev->cnf.disable_ipv6 = newf;
4454 			if (changed)
4455 				dev_disable_change(idev);
4456 		}
4457 	}
4458 	rcu_read_unlock();
4459 }
4460 
4461 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
4462 {
4463 	struct net *net;
4464 	int old;
4465 
4466 	if (!rtnl_trylock())
4467 		return restart_syscall();
4468 
4469 	net = (struct net *)table->extra2;
4470 	old = *p;
4471 	*p = newf;
4472 
4473 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
4474 		rtnl_unlock();
4475 		return 0;
4476 	}
4477 
4478 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
4479 		net->ipv6.devconf_dflt->disable_ipv6 = newf;
4480 		addrconf_disable_change(net, newf);
4481 	} else if ((!newf) ^ (!old))
4482 		dev_disable_change((struct inet6_dev *)table->extra1);
4483 
4484 	rtnl_unlock();
4485 	return 0;
4486 }
4487 
4488 static
4489 int addrconf_sysctl_disable(ctl_table *ctl, int write,
4490 			    void __user *buffer, size_t *lenp, loff_t *ppos)
4491 {
4492 	int *valp = ctl->data;
4493 	int val = *valp;
4494 	loff_t pos = *ppos;
4495 	ctl_table lctl;
4496 	int ret;
4497 
4498 	/*
4499 	 * ctl->data points to idev->cnf.disable_ipv6, we should
4500 	 * not modify it until we get the rtnl lock.
4501 	 */
4502 	lctl = *ctl;
4503 	lctl.data = &val;
4504 
4505 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
4506 
4507 	if (write)
4508 		ret = addrconf_disable_ipv6(ctl, valp, val);
4509 	if (ret)
4510 		*ppos = pos;
4511 	return ret;
4512 }
4513 
4514 static struct addrconf_sysctl_table
4515 {
4516 	struct ctl_table_header *sysctl_header;
4517 	ctl_table addrconf_vars[DEVCONF_MAX+1];
4518 } addrconf_sysctl __read_mostly = {
4519 	.sysctl_header = NULL,
4520 	.addrconf_vars = {
4521 		{
4522 			.procname	= "forwarding",
4523 			.data		= &ipv6_devconf.forwarding,
4524 			.maxlen		= sizeof(int),
4525 			.mode		= 0644,
4526 			.proc_handler	= addrconf_sysctl_forward,
4527 		},
4528 		{
4529 			.procname	= "hop_limit",
4530 			.data		= &ipv6_devconf.hop_limit,
4531 			.maxlen		= sizeof(int),
4532 			.mode		= 0644,
4533 			.proc_handler	= proc_dointvec,
4534 		},
4535 		{
4536 			.procname	= "mtu",
4537 			.data		= &ipv6_devconf.mtu6,
4538 			.maxlen		= sizeof(int),
4539 			.mode		= 0644,
4540 			.proc_handler	= proc_dointvec,
4541 		},
4542 		{
4543 			.procname	= "accept_ra",
4544 			.data		= &ipv6_devconf.accept_ra,
4545 			.maxlen		= sizeof(int),
4546 			.mode		= 0644,
4547 			.proc_handler	= proc_dointvec,
4548 		},
4549 		{
4550 			.procname	= "accept_redirects",
4551 			.data		= &ipv6_devconf.accept_redirects,
4552 			.maxlen		= sizeof(int),
4553 			.mode		= 0644,
4554 			.proc_handler	= proc_dointvec,
4555 		},
4556 		{
4557 			.procname	= "autoconf",
4558 			.data		= &ipv6_devconf.autoconf,
4559 			.maxlen		= sizeof(int),
4560 			.mode		= 0644,
4561 			.proc_handler	= proc_dointvec,
4562 		},
4563 		{
4564 			.procname	= "dad_transmits",
4565 			.data		= &ipv6_devconf.dad_transmits,
4566 			.maxlen		= sizeof(int),
4567 			.mode		= 0644,
4568 			.proc_handler	= proc_dointvec,
4569 		},
4570 		{
4571 			.procname	= "router_solicitations",
4572 			.data		= &ipv6_devconf.rtr_solicits,
4573 			.maxlen		= sizeof(int),
4574 			.mode		= 0644,
4575 			.proc_handler	= proc_dointvec,
4576 		},
4577 		{
4578 			.procname	= "router_solicitation_interval",
4579 			.data		= &ipv6_devconf.rtr_solicit_interval,
4580 			.maxlen		= sizeof(int),
4581 			.mode		= 0644,
4582 			.proc_handler	= proc_dointvec_jiffies,
4583 		},
4584 		{
4585 			.procname	= "router_solicitation_delay",
4586 			.data		= &ipv6_devconf.rtr_solicit_delay,
4587 			.maxlen		= sizeof(int),
4588 			.mode		= 0644,
4589 			.proc_handler	= proc_dointvec_jiffies,
4590 		},
4591 		{
4592 			.procname	= "force_mld_version",
4593 			.data		= &ipv6_devconf.force_mld_version,
4594 			.maxlen		= sizeof(int),
4595 			.mode		= 0644,
4596 			.proc_handler	= proc_dointvec,
4597 		},
4598 #ifdef CONFIG_IPV6_PRIVACY
4599 		{
4600 			.procname	= "use_tempaddr",
4601 			.data		= &ipv6_devconf.use_tempaddr,
4602 			.maxlen		= sizeof(int),
4603 			.mode		= 0644,
4604 			.proc_handler	= proc_dointvec,
4605 		},
4606 		{
4607 			.procname	= "temp_valid_lft",
4608 			.data		= &ipv6_devconf.temp_valid_lft,
4609 			.maxlen		= sizeof(int),
4610 			.mode		= 0644,
4611 			.proc_handler	= proc_dointvec,
4612 		},
4613 		{
4614 			.procname	= "temp_prefered_lft",
4615 			.data		= &ipv6_devconf.temp_prefered_lft,
4616 			.maxlen		= sizeof(int),
4617 			.mode		= 0644,
4618 			.proc_handler	= proc_dointvec,
4619 		},
4620 		{
4621 			.procname	= "regen_max_retry",
4622 			.data		= &ipv6_devconf.regen_max_retry,
4623 			.maxlen		= sizeof(int),
4624 			.mode		= 0644,
4625 			.proc_handler	= proc_dointvec,
4626 		},
4627 		{
4628 			.procname	= "max_desync_factor",
4629 			.data		= &ipv6_devconf.max_desync_factor,
4630 			.maxlen		= sizeof(int),
4631 			.mode		= 0644,
4632 			.proc_handler	= proc_dointvec,
4633 		},
4634 #endif
4635 		{
4636 			.procname	= "max_addresses",
4637 			.data		= &ipv6_devconf.max_addresses,
4638 			.maxlen		= sizeof(int),
4639 			.mode		= 0644,
4640 			.proc_handler	= proc_dointvec,
4641 		},
4642 		{
4643 			.procname	= "accept_ra_defrtr",
4644 			.data		= &ipv6_devconf.accept_ra_defrtr,
4645 			.maxlen		= sizeof(int),
4646 			.mode		= 0644,
4647 			.proc_handler	= proc_dointvec,
4648 		},
4649 		{
4650 			.procname	= "accept_ra_pinfo",
4651 			.data		= &ipv6_devconf.accept_ra_pinfo,
4652 			.maxlen		= sizeof(int),
4653 			.mode		= 0644,
4654 			.proc_handler	= proc_dointvec,
4655 		},
4656 #ifdef CONFIG_IPV6_ROUTER_PREF
4657 		{
4658 			.procname	= "accept_ra_rtr_pref",
4659 			.data		= &ipv6_devconf.accept_ra_rtr_pref,
4660 			.maxlen		= sizeof(int),
4661 			.mode		= 0644,
4662 			.proc_handler	= proc_dointvec,
4663 		},
4664 		{
4665 			.procname	= "router_probe_interval",
4666 			.data		= &ipv6_devconf.rtr_probe_interval,
4667 			.maxlen		= sizeof(int),
4668 			.mode		= 0644,
4669 			.proc_handler	= proc_dointvec_jiffies,
4670 		},
4671 #ifdef CONFIG_IPV6_ROUTE_INFO
4672 		{
4673 			.procname	= "accept_ra_rt_info_max_plen",
4674 			.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
4675 			.maxlen		= sizeof(int),
4676 			.mode		= 0644,
4677 			.proc_handler	= proc_dointvec,
4678 		},
4679 #endif
4680 #endif
4681 		{
4682 			.procname	= "proxy_ndp",
4683 			.data		= &ipv6_devconf.proxy_ndp,
4684 			.maxlen		= sizeof(int),
4685 			.mode		= 0644,
4686 			.proc_handler	= proc_dointvec,
4687 		},
4688 		{
4689 			.procname	= "accept_source_route",
4690 			.data		= &ipv6_devconf.accept_source_route,
4691 			.maxlen		= sizeof(int),
4692 			.mode		= 0644,
4693 			.proc_handler	= proc_dointvec,
4694 		},
4695 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
4696 		{
4697 			.procname       = "optimistic_dad",
4698 			.data           = &ipv6_devconf.optimistic_dad,
4699 			.maxlen         = sizeof(int),
4700 			.mode           = 0644,
4701 			.proc_handler   = proc_dointvec,
4702 
4703 		},
4704 #endif
4705 #ifdef CONFIG_IPV6_MROUTE
4706 		{
4707 			.procname	= "mc_forwarding",
4708 			.data		= &ipv6_devconf.mc_forwarding,
4709 			.maxlen		= sizeof(int),
4710 			.mode		= 0444,
4711 			.proc_handler	= proc_dointvec,
4712 		},
4713 #endif
4714 		{
4715 			.procname	= "disable_ipv6",
4716 			.data		= &ipv6_devconf.disable_ipv6,
4717 			.maxlen		= sizeof(int),
4718 			.mode		= 0644,
4719 			.proc_handler	= addrconf_sysctl_disable,
4720 		},
4721 		{
4722 			.procname	= "accept_dad",
4723 			.data		= &ipv6_devconf.accept_dad,
4724 			.maxlen		= sizeof(int),
4725 			.mode		= 0644,
4726 			.proc_handler	= proc_dointvec,
4727 		},
4728 		{
4729 			.procname       = "force_tllao",
4730 			.data           = &ipv6_devconf.force_tllao,
4731 			.maxlen         = sizeof(int),
4732 			.mode           = 0644,
4733 			.proc_handler   = proc_dointvec
4734 		},
4735 		{
4736 			.procname       = "ndisc_notify",
4737 			.data           = &ipv6_devconf.ndisc_notify,
4738 			.maxlen         = sizeof(int),
4739 			.mode           = 0644,
4740 			.proc_handler   = proc_dointvec
4741 		},
4742 		{
4743 			/* sentinel */
4744 		}
4745 	},
4746 };
4747 
4748 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
4749 		struct inet6_dev *idev, struct ipv6_devconf *p)
4750 {
4751 	int i;
4752 	struct addrconf_sysctl_table *t;
4753 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
4754 
4755 	t = kmemdup(&addrconf_sysctl, sizeof(*t), GFP_KERNEL);
4756 	if (t == NULL)
4757 		goto out;
4758 
4759 	for (i = 0; t->addrconf_vars[i].data; i++) {
4760 		t->addrconf_vars[i].data += (char *)p - (char *)&ipv6_devconf;
4761 		t->addrconf_vars[i].extra1 = idev; /* embedded; no ref */
4762 		t->addrconf_vars[i].extra2 = net;
4763 	}
4764 
4765 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
4766 
4767 	t->sysctl_header = register_net_sysctl(net, path, t->addrconf_vars);
4768 	if (t->sysctl_header == NULL)
4769 		goto free;
4770 
4771 	p->sysctl = t;
4772 	return 0;
4773 
4774 free:
4775 	kfree(t);
4776 out:
4777 	return -ENOBUFS;
4778 }
4779 
4780 static void __addrconf_sysctl_unregister(struct ipv6_devconf *p)
4781 {
4782 	struct addrconf_sysctl_table *t;
4783 
4784 	if (p->sysctl == NULL)
4785 		return;
4786 
4787 	t = p->sysctl;
4788 	p->sysctl = NULL;
4789 	unregister_net_sysctl_table(t->sysctl_header);
4790 	kfree(t);
4791 }
4792 
4793 static void addrconf_sysctl_register(struct inet6_dev *idev)
4794 {
4795 	neigh_sysctl_register(idev->dev, idev->nd_parms, "ipv6",
4796 			      &ndisc_ifinfo_sysctl_change);
4797 	__addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
4798 					idev, &idev->cnf);
4799 }
4800 
4801 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
4802 {
4803 	__addrconf_sysctl_unregister(&idev->cnf);
4804 	neigh_sysctl_unregister(idev->nd_parms);
4805 }
4806 
4807 
4808 #endif
4809 
4810 static int __net_init addrconf_init_net(struct net *net)
4811 {
4812 	int err = -ENOMEM;
4813 	struct ipv6_devconf *all, *dflt;
4814 
4815 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
4816 	if (all == NULL)
4817 		goto err_alloc_all;
4818 
4819 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
4820 	if (dflt == NULL)
4821 		goto err_alloc_dflt;
4822 
4823 	/* these will be inherited by all namespaces */
4824 	dflt->autoconf = ipv6_defaults.autoconf;
4825 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
4826 
4827 	net->ipv6.devconf_all = all;
4828 	net->ipv6.devconf_dflt = dflt;
4829 
4830 #ifdef CONFIG_SYSCTL
4831 	err = __addrconf_sysctl_register(net, "all", NULL, all);
4832 	if (err < 0)
4833 		goto err_reg_all;
4834 
4835 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
4836 	if (err < 0)
4837 		goto err_reg_dflt;
4838 #endif
4839 	return 0;
4840 
4841 #ifdef CONFIG_SYSCTL
4842 err_reg_dflt:
4843 	__addrconf_sysctl_unregister(all);
4844 err_reg_all:
4845 	kfree(dflt);
4846 #endif
4847 err_alloc_dflt:
4848 	kfree(all);
4849 err_alloc_all:
4850 	return err;
4851 }
4852 
4853 static void __net_exit addrconf_exit_net(struct net *net)
4854 {
4855 #ifdef CONFIG_SYSCTL
4856 	__addrconf_sysctl_unregister(net->ipv6.devconf_dflt);
4857 	__addrconf_sysctl_unregister(net->ipv6.devconf_all);
4858 #endif
4859 	if (!net_eq(net, &init_net)) {
4860 		kfree(net->ipv6.devconf_dflt);
4861 		kfree(net->ipv6.devconf_all);
4862 	}
4863 }
4864 
4865 static struct pernet_operations addrconf_ops = {
4866 	.init = addrconf_init_net,
4867 	.exit = addrconf_exit_net,
4868 };
4869 
4870 static struct rtnl_af_ops inet6_ops = {
4871 	.family		  = AF_INET6,
4872 	.fill_link_af	  = inet6_fill_link_af,
4873 	.get_link_af_size = inet6_get_link_af_size,
4874 };
4875 
4876 /*
4877  *	Init / cleanup code
4878  */
4879 
4880 int __init addrconf_init(void)
4881 {
4882 	int i, err;
4883 
4884 	err = ipv6_addr_label_init();
4885 	if (err < 0) {
4886 		pr_crit("%s: cannot initialize default policy table: %d\n",
4887 			__func__, err);
4888 		goto out;
4889 	}
4890 
4891 	err = register_pernet_subsys(&addrconf_ops);
4892 	if (err < 0)
4893 		goto out_addrlabel;
4894 
4895 	/* The addrconf netdev notifier requires that loopback_dev
4896 	 * has it's ipv6 private information allocated and setup
4897 	 * before it can bring up and give link-local addresses
4898 	 * to other devices which are up.
4899 	 *
4900 	 * Unfortunately, loopback_dev is not necessarily the first
4901 	 * entry in the global dev_base list of net devices.  In fact,
4902 	 * it is likely to be the very last entry on that list.
4903 	 * So this causes the notifier registry below to try and
4904 	 * give link-local addresses to all devices besides loopback_dev
4905 	 * first, then loopback_dev, which cases all the non-loopback_dev
4906 	 * devices to fail to get a link-local address.
4907 	 *
4908 	 * So, as a temporary fix, allocate the ipv6 structure for
4909 	 * loopback_dev first by hand.
4910 	 * Longer term, all of the dependencies ipv6 has upon the loopback
4911 	 * device and it being up should be removed.
4912 	 */
4913 	rtnl_lock();
4914 	if (!ipv6_add_dev(init_net.loopback_dev))
4915 		err = -ENOMEM;
4916 	rtnl_unlock();
4917 	if (err)
4918 		goto errlo;
4919 
4920 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
4921 		INIT_HLIST_HEAD(&inet6_addr_lst[i]);
4922 
4923 	register_netdevice_notifier(&ipv6_dev_notf);
4924 
4925 	addrconf_verify(0);
4926 
4927 	err = rtnl_af_register(&inet6_ops);
4928 	if (err < 0)
4929 		goto errout_af;
4930 
4931 	err = __rtnl_register(PF_INET6, RTM_GETLINK, NULL, inet6_dump_ifinfo,
4932 			      NULL);
4933 	if (err < 0)
4934 		goto errout;
4935 
4936 	/* Only the first call to __rtnl_register can fail */
4937 	__rtnl_register(PF_INET6, RTM_NEWADDR, inet6_rtm_newaddr, NULL, NULL);
4938 	__rtnl_register(PF_INET6, RTM_DELADDR, inet6_rtm_deladdr, NULL, NULL);
4939 	__rtnl_register(PF_INET6, RTM_GETADDR, inet6_rtm_getaddr,
4940 			inet6_dump_ifaddr, NULL);
4941 	__rtnl_register(PF_INET6, RTM_GETMULTICAST, NULL,
4942 			inet6_dump_ifmcaddr, NULL);
4943 	__rtnl_register(PF_INET6, RTM_GETANYCAST, NULL,
4944 			inet6_dump_ifacaddr, NULL);
4945 	__rtnl_register(PF_INET6, RTM_GETNETCONF, inet6_netconf_get_devconf,
4946 			NULL, NULL);
4947 
4948 	ipv6_addr_label_rtnl_register();
4949 
4950 	return 0;
4951 errout:
4952 	rtnl_af_unregister(&inet6_ops);
4953 errout_af:
4954 	unregister_netdevice_notifier(&ipv6_dev_notf);
4955 errlo:
4956 	unregister_pernet_subsys(&addrconf_ops);
4957 out_addrlabel:
4958 	ipv6_addr_label_cleanup();
4959 out:
4960 	return err;
4961 }
4962 
4963 void addrconf_cleanup(void)
4964 {
4965 	struct net_device *dev;
4966 	int i;
4967 
4968 	unregister_netdevice_notifier(&ipv6_dev_notf);
4969 	unregister_pernet_subsys(&addrconf_ops);
4970 	ipv6_addr_label_cleanup();
4971 
4972 	rtnl_lock();
4973 
4974 	__rtnl_af_unregister(&inet6_ops);
4975 
4976 	/* clean dev list */
4977 	for_each_netdev(&init_net, dev) {
4978 		if (__in6_dev_get(dev) == NULL)
4979 			continue;
4980 		addrconf_ifdown(dev, 1);
4981 	}
4982 	addrconf_ifdown(init_net.loopback_dev, 2);
4983 
4984 	/*
4985 	 *	Check hash table.
4986 	 */
4987 	spin_lock_bh(&addrconf_hash_lock);
4988 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
4989 		WARN_ON(!hlist_empty(&inet6_addr_lst[i]));
4990 	spin_unlock_bh(&addrconf_hash_lock);
4991 
4992 	del_timer(&addr_chk_timer);
4993 	rtnl_unlock();
4994 }
4995