xref: /openbmc/linux/net/ipv6/addrconf.c (revision 97da55fc)
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 ATOMIC_NOTIFIER_HEAD(inet6addr_chain);
172 
173 static struct ipv6_devconf ipv6_devconf __read_mostly = {
174 	.forwarding		= 0,
175 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
176 	.mtu6			= IPV6_MIN_MTU,
177 	.accept_ra		= 1,
178 	.accept_redirects	= 1,
179 	.autoconf		= 1,
180 	.force_mld_version	= 0,
181 	.dad_transmits		= 1,
182 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
183 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
184 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
185 #ifdef CONFIG_IPV6_PRIVACY
186 	.use_tempaddr 		= 0,
187 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
188 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
189 	.regen_max_retry	= REGEN_MAX_RETRY,
190 	.max_desync_factor	= MAX_DESYNC_FACTOR,
191 #endif
192 	.max_addresses		= IPV6_MAX_ADDRESSES,
193 	.accept_ra_defrtr	= 1,
194 	.accept_ra_pinfo	= 1,
195 #ifdef CONFIG_IPV6_ROUTER_PREF
196 	.accept_ra_rtr_pref	= 1,
197 	.rtr_probe_interval	= 60 * HZ,
198 #ifdef CONFIG_IPV6_ROUTE_INFO
199 	.accept_ra_rt_info_max_plen = 0,
200 #endif
201 #endif
202 	.proxy_ndp		= 0,
203 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
204 	.disable_ipv6		= 0,
205 	.accept_dad		= 1,
206 };
207 
208 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
209 	.forwarding		= 0,
210 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
211 	.mtu6			= IPV6_MIN_MTU,
212 	.accept_ra		= 1,
213 	.accept_redirects	= 1,
214 	.autoconf		= 1,
215 	.dad_transmits		= 1,
216 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
217 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
218 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
219 #ifdef CONFIG_IPV6_PRIVACY
220 	.use_tempaddr		= 0,
221 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
222 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
223 	.regen_max_retry	= REGEN_MAX_RETRY,
224 	.max_desync_factor	= MAX_DESYNC_FACTOR,
225 #endif
226 	.max_addresses		= IPV6_MAX_ADDRESSES,
227 	.accept_ra_defrtr	= 1,
228 	.accept_ra_pinfo	= 1,
229 #ifdef CONFIG_IPV6_ROUTER_PREF
230 	.accept_ra_rtr_pref	= 1,
231 	.rtr_probe_interval	= 60 * HZ,
232 #ifdef CONFIG_IPV6_ROUTE_INFO
233 	.accept_ra_rt_info_max_plen = 0,
234 #endif
235 #endif
236 	.proxy_ndp		= 0,
237 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
238 	.disable_ipv6		= 0,
239 	.accept_dad		= 1,
240 };
241 
242 /* IPv6 Wildcard Address and Loopback Address defined by RFC2553 */
243 const struct in6_addr in6addr_any = IN6ADDR_ANY_INIT;
244 const struct in6_addr in6addr_loopback = IN6ADDR_LOOPBACK_INIT;
245 const struct in6_addr in6addr_linklocal_allnodes = IN6ADDR_LINKLOCAL_ALLNODES_INIT;
246 const struct in6_addr in6addr_linklocal_allrouters = IN6ADDR_LINKLOCAL_ALLROUTERS_INIT;
247 const struct in6_addr in6addr_interfacelocal_allnodes = IN6ADDR_INTERFACELOCAL_ALLNODES_INIT;
248 const struct in6_addr in6addr_interfacelocal_allrouters = IN6ADDR_INTERFACELOCAL_ALLROUTERS_INIT;
249 const struct in6_addr in6addr_sitelocal_allrouters = IN6ADDR_SITELOCAL_ALLROUTERS_INIT;
250 
251 /* Check if a valid qdisc is available */
252 static inline bool addrconf_qdisc_ok(const struct net_device *dev)
253 {
254 	return !qdisc_tx_is_noop(dev);
255 }
256 
257 static void addrconf_del_timer(struct inet6_ifaddr *ifp)
258 {
259 	if (del_timer(&ifp->timer))
260 		__in6_ifa_put(ifp);
261 }
262 
263 enum addrconf_timer_t {
264 	AC_NONE,
265 	AC_DAD,
266 	AC_RS,
267 };
268 
269 static void addrconf_mod_timer(struct inet6_ifaddr *ifp,
270 			       enum addrconf_timer_t what,
271 			       unsigned long when)
272 {
273 	if (!del_timer(&ifp->timer))
274 		in6_ifa_hold(ifp);
275 
276 	switch (what) {
277 	case AC_DAD:
278 		ifp->timer.function = addrconf_dad_timer;
279 		break;
280 	case AC_RS:
281 		ifp->timer.function = addrconf_rs_timer;
282 		break;
283 	default:
284 		break;
285 	}
286 	ifp->timer.expires = jiffies + when;
287 	add_timer(&ifp->timer);
288 }
289 
290 static int snmp6_alloc_dev(struct inet6_dev *idev)
291 {
292 	if (snmp_mib_init((void __percpu **)idev->stats.ipv6,
293 			  sizeof(struct ipstats_mib),
294 			  __alignof__(struct ipstats_mib)) < 0)
295 		goto err_ip;
296 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
297 					GFP_KERNEL);
298 	if (!idev->stats.icmpv6dev)
299 		goto err_icmp;
300 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
301 					   GFP_KERNEL);
302 	if (!idev->stats.icmpv6msgdev)
303 		goto err_icmpmsg;
304 
305 	return 0;
306 
307 err_icmpmsg:
308 	kfree(idev->stats.icmpv6dev);
309 err_icmp:
310 	snmp_mib_free((void __percpu **)idev->stats.ipv6);
311 err_ip:
312 	return -ENOMEM;
313 }
314 
315 static void snmp6_free_dev(struct inet6_dev *idev)
316 {
317 	kfree(idev->stats.icmpv6msgdev);
318 	kfree(idev->stats.icmpv6dev);
319 	snmp_mib_free((void __percpu **)idev->stats.ipv6);
320 }
321 
322 /* Nobody refers to this device, we may destroy it. */
323 
324 void in6_dev_finish_destroy(struct inet6_dev *idev)
325 {
326 	struct net_device *dev = idev->dev;
327 
328 	WARN_ON(!list_empty(&idev->addr_list));
329 	WARN_ON(idev->mc_list != NULL);
330 
331 #ifdef NET_REFCNT_DEBUG
332 	pr_debug("%s: %s\n", __func__, dev ? dev->name : "NIL");
333 #endif
334 	dev_put(dev);
335 	if (!idev->dead) {
336 		pr_warn("Freeing alive inet6 device %p\n", idev);
337 		return;
338 	}
339 	snmp6_free_dev(idev);
340 	kfree_rcu(idev, rcu);
341 }
342 EXPORT_SYMBOL(in6_dev_finish_destroy);
343 
344 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
345 {
346 	struct inet6_dev *ndev;
347 
348 	ASSERT_RTNL();
349 
350 	if (dev->mtu < IPV6_MIN_MTU)
351 		return NULL;
352 
353 	ndev = kzalloc(sizeof(struct inet6_dev), GFP_KERNEL);
354 
355 	if (ndev == NULL)
356 		return NULL;
357 
358 	rwlock_init(&ndev->lock);
359 	ndev->dev = dev;
360 	INIT_LIST_HEAD(&ndev->addr_list);
361 
362 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
363 	ndev->cnf.mtu6 = dev->mtu;
364 	ndev->cnf.sysctl = NULL;
365 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
366 	if (ndev->nd_parms == NULL) {
367 		kfree(ndev);
368 		return NULL;
369 	}
370 	if (ndev->cnf.forwarding)
371 		dev_disable_lro(dev);
372 	/* We refer to the device */
373 	dev_hold(dev);
374 
375 	if (snmp6_alloc_dev(ndev) < 0) {
376 		ADBG((KERN_WARNING
377 			"%s: cannot allocate memory for statistics; dev=%s.\n",
378 			__func__, dev->name));
379 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
380 		dev_put(dev);
381 		kfree(ndev);
382 		return NULL;
383 	}
384 
385 	if (snmp6_register_dev(ndev) < 0) {
386 		ADBG((KERN_WARNING
387 			"%s: cannot create /proc/net/dev_snmp6/%s\n",
388 			__func__, dev->name));
389 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
390 		ndev->dead = 1;
391 		in6_dev_finish_destroy(ndev);
392 		return NULL;
393 	}
394 
395 	/* One reference from device.  We must do this before
396 	 * we invoke __ipv6_regen_rndid().
397 	 */
398 	in6_dev_hold(ndev);
399 
400 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
401 		ndev->cnf.accept_dad = -1;
402 
403 #if IS_ENABLED(CONFIG_IPV6_SIT)
404 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
405 		pr_info("%s: Disabled Multicast RS\n", dev->name);
406 		ndev->cnf.rtr_solicits = 0;
407 	}
408 #endif
409 
410 #ifdef CONFIG_IPV6_PRIVACY
411 	INIT_LIST_HEAD(&ndev->tempaddr_list);
412 	setup_timer(&ndev->regen_timer, ipv6_regen_rndid, (unsigned long)ndev);
413 	if ((dev->flags&IFF_LOOPBACK) ||
414 	    dev->type == ARPHRD_TUNNEL ||
415 	    dev->type == ARPHRD_TUNNEL6 ||
416 	    dev->type == ARPHRD_SIT ||
417 	    dev->type == ARPHRD_NONE) {
418 		ndev->cnf.use_tempaddr = -1;
419 	} else {
420 		in6_dev_hold(ndev);
421 		ipv6_regen_rndid((unsigned long) ndev);
422 	}
423 #endif
424 
425 	if (netif_running(dev) && addrconf_qdisc_ok(dev))
426 		ndev->if_flags |= IF_READY;
427 
428 	ipv6_mc_init_dev(ndev);
429 	ndev->tstamp = jiffies;
430 	addrconf_sysctl_register(ndev);
431 	/* protected by rtnl_lock */
432 	rcu_assign_pointer(dev->ip6_ptr, ndev);
433 
434 	/* Join interface-local all-node multicast group */
435 	ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes);
436 
437 	/* Join all-node multicast group */
438 	ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
439 
440 	/* Join all-router multicast group if forwarding is set */
441 	if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
442 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
443 
444 	return ndev;
445 }
446 
447 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
448 {
449 	struct inet6_dev *idev;
450 
451 	ASSERT_RTNL();
452 
453 	idev = __in6_dev_get(dev);
454 	if (!idev) {
455 		idev = ipv6_add_dev(dev);
456 		if (!idev)
457 			return NULL;
458 	}
459 
460 	if (dev->flags&IFF_UP)
461 		ipv6_mc_up(idev);
462 	return idev;
463 }
464 
465 static int inet6_netconf_msgsize_devconf(int type)
466 {
467 	int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
468 		    + nla_total_size(4);	/* NETCONFA_IFINDEX */
469 
470 	/* type -1 is used for ALL */
471 	if (type == -1 || type == NETCONFA_FORWARDING)
472 		size += nla_total_size(4);
473 #ifdef CONFIG_IPV6_MROUTE
474 	if (type == -1 || type == NETCONFA_MC_FORWARDING)
475 		size += nla_total_size(4);
476 #endif
477 
478 	return size;
479 }
480 
481 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
482 				      struct ipv6_devconf *devconf, u32 portid,
483 				      u32 seq, int event, unsigned int flags,
484 				      int type)
485 {
486 	struct nlmsghdr  *nlh;
487 	struct netconfmsg *ncm;
488 
489 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
490 			flags);
491 	if (nlh == NULL)
492 		return -EMSGSIZE;
493 
494 	ncm = nlmsg_data(nlh);
495 	ncm->ncm_family = AF_INET6;
496 
497 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
498 		goto nla_put_failure;
499 
500 	/* type -1 is used for ALL */
501 	if ((type == -1 || type == NETCONFA_FORWARDING) &&
502 	    nla_put_s32(skb, NETCONFA_FORWARDING, devconf->forwarding) < 0)
503 		goto nla_put_failure;
504 #ifdef CONFIG_IPV6_MROUTE
505 	if ((type == -1 || type == NETCONFA_MC_FORWARDING) &&
506 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
507 			devconf->mc_forwarding) < 0)
508 		goto nla_put_failure;
509 #endif
510 	return nlmsg_end(skb, nlh);
511 
512 nla_put_failure:
513 	nlmsg_cancel(skb, nlh);
514 	return -EMSGSIZE;
515 }
516 
517 void inet6_netconf_notify_devconf(struct net *net, int type, int ifindex,
518 				  struct ipv6_devconf *devconf)
519 {
520 	struct sk_buff *skb;
521 	int err = -ENOBUFS;
522 
523 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_ATOMIC);
524 	if (skb == NULL)
525 		goto errout;
526 
527 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
528 					 RTM_NEWNETCONF, 0, type);
529 	if (err < 0) {
530 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
531 		WARN_ON(err == -EMSGSIZE);
532 		kfree_skb(skb);
533 		goto errout;
534 	}
535 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_ATOMIC);
536 	return;
537 errout:
538 	rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
539 }
540 
541 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
542 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
543 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
544 };
545 
546 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
547 				     struct nlmsghdr *nlh,
548 				     void *arg)
549 {
550 	struct net *net = sock_net(in_skb->sk);
551 	struct nlattr *tb[NETCONFA_MAX+1];
552 	struct netconfmsg *ncm;
553 	struct sk_buff *skb;
554 	struct ipv6_devconf *devconf;
555 	struct inet6_dev *in6_dev;
556 	struct net_device *dev;
557 	int ifindex;
558 	int err;
559 
560 	err = nlmsg_parse(nlh, sizeof(*ncm), tb, NETCONFA_MAX,
561 			  devconf_ipv6_policy);
562 	if (err < 0)
563 		goto errout;
564 
565 	err = EINVAL;
566 	if (!tb[NETCONFA_IFINDEX])
567 		goto errout;
568 
569 	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
570 	switch (ifindex) {
571 	case NETCONFA_IFINDEX_ALL:
572 		devconf = net->ipv6.devconf_all;
573 		break;
574 	case NETCONFA_IFINDEX_DEFAULT:
575 		devconf = net->ipv6.devconf_dflt;
576 		break;
577 	default:
578 		dev = __dev_get_by_index(net, ifindex);
579 		if (dev == NULL)
580 			goto errout;
581 		in6_dev = __in6_dev_get(dev);
582 		if (in6_dev == NULL)
583 			goto errout;
584 		devconf = &in6_dev->cnf;
585 		break;
586 	}
587 
588 	err = -ENOBUFS;
589 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(-1), GFP_ATOMIC);
590 	if (skb == NULL)
591 		goto errout;
592 
593 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
594 					 NETLINK_CB(in_skb).portid,
595 					 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
596 					 -1);
597 	if (err < 0) {
598 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
599 		WARN_ON(err == -EMSGSIZE);
600 		kfree_skb(skb);
601 		goto errout;
602 	}
603 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
604 errout:
605 	return err;
606 }
607 
608 #ifdef CONFIG_SYSCTL
609 static void dev_forward_change(struct inet6_dev *idev)
610 {
611 	struct net_device *dev;
612 	struct inet6_ifaddr *ifa;
613 
614 	if (!idev)
615 		return;
616 	dev = idev->dev;
617 	if (idev->cnf.forwarding)
618 		dev_disable_lro(dev);
619 	if (dev->flags & IFF_MULTICAST) {
620 		if (idev->cnf.forwarding) {
621 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
622 			ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
623 			ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters);
624 		} else {
625 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
626 			ipv6_dev_mc_dec(dev, &in6addr_interfacelocal_allrouters);
627 			ipv6_dev_mc_dec(dev, &in6addr_sitelocal_allrouters);
628 		}
629 	}
630 
631 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
632 		if (ifa->flags&IFA_F_TENTATIVE)
633 			continue;
634 		if (idev->cnf.forwarding)
635 			addrconf_join_anycast(ifa);
636 		else
637 			addrconf_leave_anycast(ifa);
638 	}
639 	inet6_netconf_notify_devconf(dev_net(dev), NETCONFA_FORWARDING,
640 				     dev->ifindex, &idev->cnf);
641 }
642 
643 
644 static void addrconf_forward_change(struct net *net, __s32 newf)
645 {
646 	struct net_device *dev;
647 	struct inet6_dev *idev;
648 
649 	for_each_netdev(net, dev) {
650 		idev = __in6_dev_get(dev);
651 		if (idev) {
652 			int changed = (!idev->cnf.forwarding) ^ (!newf);
653 			idev->cnf.forwarding = newf;
654 			if (changed)
655 				dev_forward_change(idev);
656 		}
657 	}
658 }
659 
660 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int newf)
661 {
662 	struct net *net;
663 	int old;
664 
665 	if (!rtnl_trylock())
666 		return restart_syscall();
667 
668 	net = (struct net *)table->extra2;
669 	old = *p;
670 	*p = newf;
671 
672 	if (p == &net->ipv6.devconf_dflt->forwarding) {
673 		if ((!newf) ^ (!old))
674 			inet6_netconf_notify_devconf(net, NETCONFA_FORWARDING,
675 						     NETCONFA_IFINDEX_DEFAULT,
676 						     net->ipv6.devconf_dflt);
677 		rtnl_unlock();
678 		return 0;
679 	}
680 
681 	if (p == &net->ipv6.devconf_all->forwarding) {
682 		net->ipv6.devconf_dflt->forwarding = newf;
683 		addrconf_forward_change(net, newf);
684 		if ((!newf) ^ (!old))
685 			inet6_netconf_notify_devconf(net, NETCONFA_FORWARDING,
686 						     NETCONFA_IFINDEX_ALL,
687 						     net->ipv6.devconf_all);
688 	} else if ((!newf) ^ (!old))
689 		dev_forward_change((struct inet6_dev *)table->extra1);
690 	rtnl_unlock();
691 
692 	if (newf)
693 		rt6_purge_dflt_routers(net);
694 	return 1;
695 }
696 #endif
697 
698 /* Nobody refers to this ifaddr, destroy it */
699 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
700 {
701 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
702 
703 #ifdef NET_REFCNT_DEBUG
704 	pr_debug("%s\n", __func__);
705 #endif
706 
707 	in6_dev_put(ifp->idev);
708 
709 	if (del_timer(&ifp->timer))
710 		pr_notice("Timer is still running, when freeing ifa=%p\n", ifp);
711 
712 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
713 		pr_warn("Freeing alive inet6 address %p\n", ifp);
714 		return;
715 	}
716 	ip6_rt_put(ifp->rt);
717 
718 	kfree_rcu(ifp, rcu);
719 }
720 
721 static void
722 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
723 {
724 	struct list_head *p;
725 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
726 
727 	/*
728 	 * Each device address list is sorted in order of scope -
729 	 * global before linklocal.
730 	 */
731 	list_for_each(p, &idev->addr_list) {
732 		struct inet6_ifaddr *ifa
733 			= list_entry(p, struct inet6_ifaddr, if_list);
734 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
735 			break;
736 	}
737 
738 	list_add_tail(&ifp->if_list, p);
739 }
740 
741 static u32 inet6_addr_hash(const struct in6_addr *addr)
742 {
743 	return hash_32(ipv6_addr_hash(addr), IN6_ADDR_HSIZE_SHIFT);
744 }
745 
746 /* On success it returns ifp with increased reference count */
747 
748 static struct inet6_ifaddr *
749 ipv6_add_addr(struct inet6_dev *idev, const struct in6_addr *addr, int pfxlen,
750 	      int scope, u32 flags)
751 {
752 	struct inet6_ifaddr *ifa = NULL;
753 	struct rt6_info *rt;
754 	unsigned int hash;
755 	int err = 0;
756 	int addr_type = ipv6_addr_type(addr);
757 
758 	if (addr_type == IPV6_ADDR_ANY ||
759 	    addr_type & IPV6_ADDR_MULTICAST ||
760 	    (!(idev->dev->flags & IFF_LOOPBACK) &&
761 	     addr_type & IPV6_ADDR_LOOPBACK))
762 		return ERR_PTR(-EADDRNOTAVAIL);
763 
764 	rcu_read_lock_bh();
765 	if (idev->dead) {
766 		err = -ENODEV;			/*XXX*/
767 		goto out2;
768 	}
769 
770 	if (idev->cnf.disable_ipv6) {
771 		err = -EACCES;
772 		goto out2;
773 	}
774 
775 	spin_lock(&addrconf_hash_lock);
776 
777 	/* Ignore adding duplicate addresses on an interface */
778 	if (ipv6_chk_same_addr(dev_net(idev->dev), addr, idev->dev)) {
779 		ADBG(("ipv6_add_addr: already assigned\n"));
780 		err = -EEXIST;
781 		goto out;
782 	}
783 
784 	ifa = kzalloc(sizeof(struct inet6_ifaddr), GFP_ATOMIC);
785 
786 	if (ifa == NULL) {
787 		ADBG(("ipv6_add_addr: malloc failed\n"));
788 		err = -ENOBUFS;
789 		goto out;
790 	}
791 
792 	rt = addrconf_dst_alloc(idev, addr, false);
793 	if (IS_ERR(rt)) {
794 		err = PTR_ERR(rt);
795 		goto out;
796 	}
797 
798 	ifa->addr = *addr;
799 
800 	spin_lock_init(&ifa->lock);
801 	spin_lock_init(&ifa->state_lock);
802 	init_timer(&ifa->timer);
803 	INIT_HLIST_NODE(&ifa->addr_lst);
804 	ifa->timer.data = (unsigned long) ifa;
805 	ifa->scope = scope;
806 	ifa->prefix_len = pfxlen;
807 	ifa->flags = flags | IFA_F_TENTATIVE;
808 	ifa->cstamp = ifa->tstamp = jiffies;
809 
810 	ifa->rt = rt;
811 
812 	ifa->idev = idev;
813 	in6_dev_hold(idev);
814 	/* For caller */
815 	in6_ifa_hold(ifa);
816 
817 	/* Add to big hash table */
818 	hash = inet6_addr_hash(addr);
819 
820 	hlist_add_head_rcu(&ifa->addr_lst, &inet6_addr_lst[hash]);
821 	spin_unlock(&addrconf_hash_lock);
822 
823 	write_lock(&idev->lock);
824 	/* Add to inet6_dev unicast addr list. */
825 	ipv6_link_dev_addr(idev, ifa);
826 
827 #ifdef CONFIG_IPV6_PRIVACY
828 	if (ifa->flags&IFA_F_TEMPORARY) {
829 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
830 		in6_ifa_hold(ifa);
831 	}
832 #endif
833 
834 	in6_ifa_hold(ifa);
835 	write_unlock(&idev->lock);
836 out2:
837 	rcu_read_unlock_bh();
838 
839 	if (likely(err == 0))
840 		atomic_notifier_call_chain(&inet6addr_chain, NETDEV_UP, ifa);
841 	else {
842 		kfree(ifa);
843 		ifa = ERR_PTR(err);
844 	}
845 
846 	return ifa;
847 out:
848 	spin_unlock(&addrconf_hash_lock);
849 	goto out2;
850 }
851 
852 /* This function wants to get referenced ifp and releases it before return */
853 
854 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
855 {
856 	struct inet6_ifaddr *ifa, *ifn;
857 	struct inet6_dev *idev = ifp->idev;
858 	int state;
859 	int deleted = 0, onlink = 0;
860 	unsigned long expires = jiffies;
861 
862 	spin_lock_bh(&ifp->state_lock);
863 	state = ifp->state;
864 	ifp->state = INET6_IFADDR_STATE_DEAD;
865 	spin_unlock_bh(&ifp->state_lock);
866 
867 	if (state == INET6_IFADDR_STATE_DEAD)
868 		goto out;
869 
870 	spin_lock_bh(&addrconf_hash_lock);
871 	hlist_del_init_rcu(&ifp->addr_lst);
872 	spin_unlock_bh(&addrconf_hash_lock);
873 
874 	write_lock_bh(&idev->lock);
875 #ifdef CONFIG_IPV6_PRIVACY
876 	if (ifp->flags&IFA_F_TEMPORARY) {
877 		list_del(&ifp->tmp_list);
878 		if (ifp->ifpub) {
879 			in6_ifa_put(ifp->ifpub);
880 			ifp->ifpub = NULL;
881 		}
882 		__in6_ifa_put(ifp);
883 	}
884 #endif
885 
886 	list_for_each_entry_safe(ifa, ifn, &idev->addr_list, if_list) {
887 		if (ifa == ifp) {
888 			list_del_init(&ifp->if_list);
889 			__in6_ifa_put(ifp);
890 
891 			if (!(ifp->flags & IFA_F_PERMANENT) || onlink > 0)
892 				break;
893 			deleted = 1;
894 			continue;
895 		} else if (ifp->flags & IFA_F_PERMANENT) {
896 			if (ipv6_prefix_equal(&ifa->addr, &ifp->addr,
897 					      ifp->prefix_len)) {
898 				if (ifa->flags & IFA_F_PERMANENT) {
899 					onlink = 1;
900 					if (deleted)
901 						break;
902 				} else {
903 					unsigned long lifetime;
904 
905 					if (!onlink)
906 						onlink = -1;
907 
908 					spin_lock(&ifa->lock);
909 
910 					lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
911 					/*
912 					 * Note: Because this address is
913 					 * not permanent, lifetime <
914 					 * LONG_MAX / HZ here.
915 					 */
916 					if (time_before(expires,
917 							ifa->tstamp + lifetime * HZ))
918 						expires = ifa->tstamp + lifetime * HZ;
919 					spin_unlock(&ifa->lock);
920 				}
921 			}
922 		}
923 	}
924 	write_unlock_bh(&idev->lock);
925 
926 	addrconf_del_timer(ifp);
927 
928 	ipv6_ifa_notify(RTM_DELADDR, ifp);
929 
930 	atomic_notifier_call_chain(&inet6addr_chain, NETDEV_DOWN, ifp);
931 
932 	/*
933 	 * Purge or update corresponding prefix
934 	 *
935 	 * 1) we don't purge prefix here if address was not permanent.
936 	 *    prefix is managed by its own lifetime.
937 	 * 2) if there're no addresses, delete prefix.
938 	 * 3) if there're still other permanent address(es),
939 	 *    corresponding prefix is still permanent.
940 	 * 4) otherwise, update prefix lifetime to the
941 	 *    longest valid lifetime among the corresponding
942 	 *    addresses on the device.
943 	 *    Note: subsequent RA will update lifetime.
944 	 *
945 	 * --yoshfuji
946 	 */
947 	if ((ifp->flags & IFA_F_PERMANENT) && onlink < 1) {
948 		struct in6_addr prefix;
949 		struct rt6_info *rt;
950 
951 		ipv6_addr_prefix(&prefix, &ifp->addr, ifp->prefix_len);
952 
953 		rt = addrconf_get_prefix_route(&prefix,
954 					       ifp->prefix_len,
955 					       ifp->idev->dev,
956 					       0, RTF_GATEWAY | RTF_DEFAULT);
957 
958 		if (rt) {
959 			if (onlink == 0) {
960 				ip6_del_rt(rt);
961 				rt = NULL;
962 			} else if (!(rt->rt6i_flags & RTF_EXPIRES)) {
963 				rt6_set_expires(rt, expires);
964 			}
965 		}
966 		ip6_rt_put(rt);
967 	}
968 
969 	/* clean up prefsrc entries */
970 	rt6_remove_prefsrc(ifp);
971 out:
972 	in6_ifa_put(ifp);
973 }
974 
975 #ifdef CONFIG_IPV6_PRIVACY
976 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp, struct inet6_ifaddr *ift)
977 {
978 	struct inet6_dev *idev = ifp->idev;
979 	struct in6_addr addr, *tmpaddr;
980 	unsigned long tmp_prefered_lft, tmp_valid_lft, tmp_tstamp, age;
981 	unsigned long regen_advance;
982 	int tmp_plen;
983 	int ret = 0;
984 	int max_addresses;
985 	u32 addr_flags;
986 	unsigned long now = jiffies;
987 
988 	write_lock(&idev->lock);
989 	if (ift) {
990 		spin_lock_bh(&ift->lock);
991 		memcpy(&addr.s6_addr[8], &ift->addr.s6_addr[8], 8);
992 		spin_unlock_bh(&ift->lock);
993 		tmpaddr = &addr;
994 	} else {
995 		tmpaddr = NULL;
996 	}
997 retry:
998 	in6_dev_hold(idev);
999 	if (idev->cnf.use_tempaddr <= 0) {
1000 		write_unlock(&idev->lock);
1001 		pr_info("%s: use_tempaddr is disabled\n", __func__);
1002 		in6_dev_put(idev);
1003 		ret = -1;
1004 		goto out;
1005 	}
1006 	spin_lock_bh(&ifp->lock);
1007 	if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
1008 		idev->cnf.use_tempaddr = -1;	/*XXX*/
1009 		spin_unlock_bh(&ifp->lock);
1010 		write_unlock(&idev->lock);
1011 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1012 			__func__);
1013 		in6_dev_put(idev);
1014 		ret = -1;
1015 		goto out;
1016 	}
1017 	in6_ifa_hold(ifp);
1018 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1019 	__ipv6_try_regen_rndid(idev, tmpaddr);
1020 	memcpy(&addr.s6_addr[8], idev->rndid, 8);
1021 	age = (now - ifp->tstamp) / HZ;
1022 	tmp_valid_lft = min_t(__u32,
1023 			      ifp->valid_lft,
1024 			      idev->cnf.temp_valid_lft + age);
1025 	tmp_prefered_lft = min_t(__u32,
1026 				 ifp->prefered_lft,
1027 				 idev->cnf.temp_prefered_lft + age -
1028 				 idev->cnf.max_desync_factor);
1029 	tmp_plen = ifp->prefix_len;
1030 	max_addresses = idev->cnf.max_addresses;
1031 	tmp_tstamp = ifp->tstamp;
1032 	spin_unlock_bh(&ifp->lock);
1033 
1034 	regen_advance = idev->cnf.regen_max_retry *
1035 	                idev->cnf.dad_transmits *
1036 	                idev->nd_parms->retrans_time / HZ;
1037 	write_unlock(&idev->lock);
1038 
1039 	/* A temporary address is created only if this calculated Preferred
1040 	 * Lifetime is greater than REGEN_ADVANCE time units.  In particular,
1041 	 * an implementation must not create a temporary address with a zero
1042 	 * Preferred Lifetime.
1043 	 */
1044 	if (tmp_prefered_lft <= regen_advance) {
1045 		in6_ifa_put(ifp);
1046 		in6_dev_put(idev);
1047 		ret = -1;
1048 		goto out;
1049 	}
1050 
1051 	addr_flags = IFA_F_TEMPORARY;
1052 	/* set in addrconf_prefix_rcv() */
1053 	if (ifp->flags & IFA_F_OPTIMISTIC)
1054 		addr_flags |= IFA_F_OPTIMISTIC;
1055 
1056 	ift = !max_addresses ||
1057 	      ipv6_count_addresses(idev) < max_addresses ?
1058 		ipv6_add_addr(idev, &addr, tmp_plen,
1059 			      ipv6_addr_type(&addr)&IPV6_ADDR_SCOPE_MASK,
1060 			      addr_flags) : NULL;
1061 	if (IS_ERR_OR_NULL(ift)) {
1062 		in6_ifa_put(ifp);
1063 		in6_dev_put(idev);
1064 		pr_info("%s: retry temporary address regeneration\n", __func__);
1065 		tmpaddr = &addr;
1066 		write_lock(&idev->lock);
1067 		goto retry;
1068 	}
1069 
1070 	spin_lock_bh(&ift->lock);
1071 	ift->ifpub = ifp;
1072 	ift->valid_lft = tmp_valid_lft;
1073 	ift->prefered_lft = tmp_prefered_lft;
1074 	ift->cstamp = now;
1075 	ift->tstamp = tmp_tstamp;
1076 	spin_unlock_bh(&ift->lock);
1077 
1078 	addrconf_dad_start(ift);
1079 	in6_ifa_put(ift);
1080 	in6_dev_put(idev);
1081 out:
1082 	return ret;
1083 }
1084 #endif
1085 
1086 /*
1087  *	Choose an appropriate source address (RFC3484)
1088  */
1089 enum {
1090 	IPV6_SADDR_RULE_INIT = 0,
1091 	IPV6_SADDR_RULE_LOCAL,
1092 	IPV6_SADDR_RULE_SCOPE,
1093 	IPV6_SADDR_RULE_PREFERRED,
1094 #ifdef CONFIG_IPV6_MIP6
1095 	IPV6_SADDR_RULE_HOA,
1096 #endif
1097 	IPV6_SADDR_RULE_OIF,
1098 	IPV6_SADDR_RULE_LABEL,
1099 #ifdef CONFIG_IPV6_PRIVACY
1100 	IPV6_SADDR_RULE_PRIVACY,
1101 #endif
1102 	IPV6_SADDR_RULE_ORCHID,
1103 	IPV6_SADDR_RULE_PREFIX,
1104 	IPV6_SADDR_RULE_MAX
1105 };
1106 
1107 struct ipv6_saddr_score {
1108 	int			rule;
1109 	int			addr_type;
1110 	struct inet6_ifaddr	*ifa;
1111 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1112 	int			scopedist;
1113 	int			matchlen;
1114 };
1115 
1116 struct ipv6_saddr_dst {
1117 	const struct in6_addr *addr;
1118 	int ifindex;
1119 	int scope;
1120 	int label;
1121 	unsigned int prefs;
1122 };
1123 
1124 static inline int ipv6_saddr_preferred(int type)
1125 {
1126 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1127 		return 1;
1128 	return 0;
1129 }
1130 
1131 static int ipv6_get_saddr_eval(struct net *net,
1132 			       struct ipv6_saddr_score *score,
1133 			       struct ipv6_saddr_dst *dst,
1134 			       int i)
1135 {
1136 	int ret;
1137 
1138 	if (i <= score->rule) {
1139 		switch (i) {
1140 		case IPV6_SADDR_RULE_SCOPE:
1141 			ret = score->scopedist;
1142 			break;
1143 		case IPV6_SADDR_RULE_PREFIX:
1144 			ret = score->matchlen;
1145 			break;
1146 		default:
1147 			ret = !!test_bit(i, score->scorebits);
1148 		}
1149 		goto out;
1150 	}
1151 
1152 	switch (i) {
1153 	case IPV6_SADDR_RULE_INIT:
1154 		/* Rule 0: remember if hiscore is not ready yet */
1155 		ret = !!score->ifa;
1156 		break;
1157 	case IPV6_SADDR_RULE_LOCAL:
1158 		/* Rule 1: Prefer same address */
1159 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1160 		break;
1161 	case IPV6_SADDR_RULE_SCOPE:
1162 		/* Rule 2: Prefer appropriate scope
1163 		 *
1164 		 *      ret
1165 		 *       ^
1166 		 *    -1 |  d 15
1167 		 *    ---+--+-+---> scope
1168 		 *       |
1169 		 *       |             d is scope of the destination.
1170 		 *  B-d  |  \
1171 		 *       |   \      <- smaller scope is better if
1172 		 *  B-15 |    \        if scope is enough for destinaion.
1173 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1174 		 * d-C-1 | /
1175 		 *       |/         <- greater is better
1176 		 *   -C  /             if scope is not enough for destination.
1177 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1178 		 *
1179 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1180 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1181 		 * Assume B = 0 and we get C > 29.
1182 		 */
1183 		ret = __ipv6_addr_src_scope(score->addr_type);
1184 		if (ret >= dst->scope)
1185 			ret = -ret;
1186 		else
1187 			ret -= 128;	/* 30 is enough */
1188 		score->scopedist = ret;
1189 		break;
1190 	case IPV6_SADDR_RULE_PREFERRED:
1191 		/* Rule 3: Avoid deprecated and optimistic addresses */
1192 		ret = ipv6_saddr_preferred(score->addr_type) ||
1193 		      !(score->ifa->flags & (IFA_F_DEPRECATED|IFA_F_OPTIMISTIC));
1194 		break;
1195 #ifdef CONFIG_IPV6_MIP6
1196 	case IPV6_SADDR_RULE_HOA:
1197 	    {
1198 		/* Rule 4: Prefer home address */
1199 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1200 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1201 		break;
1202 	    }
1203 #endif
1204 	case IPV6_SADDR_RULE_OIF:
1205 		/* Rule 5: Prefer outgoing interface */
1206 		ret = (!dst->ifindex ||
1207 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1208 		break;
1209 	case IPV6_SADDR_RULE_LABEL:
1210 		/* Rule 6: Prefer matching label */
1211 		ret = ipv6_addr_label(net,
1212 				      &score->ifa->addr, score->addr_type,
1213 				      score->ifa->idev->dev->ifindex) == dst->label;
1214 		break;
1215 #ifdef CONFIG_IPV6_PRIVACY
1216 	case IPV6_SADDR_RULE_PRIVACY:
1217 	    {
1218 		/* Rule 7: Prefer public address
1219 		 * Note: prefer temporary address if use_tempaddr >= 2
1220 		 */
1221 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1222 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1223 				score->ifa->idev->cnf.use_tempaddr >= 2;
1224 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1225 		break;
1226 	    }
1227 #endif
1228 	case IPV6_SADDR_RULE_ORCHID:
1229 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1230 		 *	    non-ORCHID vs non-ORCHID
1231 		 */
1232 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1233 			ipv6_addr_orchid(dst->addr));
1234 		break;
1235 	case IPV6_SADDR_RULE_PREFIX:
1236 		/* Rule 8: Use longest matching prefix */
1237 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1238 		if (ret > score->ifa->prefix_len)
1239 			ret = score->ifa->prefix_len;
1240 		score->matchlen = ret;
1241 		break;
1242 	default:
1243 		ret = 0;
1244 	}
1245 
1246 	if (ret)
1247 		__set_bit(i, score->scorebits);
1248 	score->rule = i;
1249 out:
1250 	return ret;
1251 }
1252 
1253 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1254 		       const struct in6_addr *daddr, unsigned int prefs,
1255 		       struct in6_addr *saddr)
1256 {
1257 	struct ipv6_saddr_score scores[2],
1258 				*score = &scores[0], *hiscore = &scores[1];
1259 	struct ipv6_saddr_dst dst;
1260 	struct net_device *dev;
1261 	int dst_type;
1262 
1263 	dst_type = __ipv6_addr_type(daddr);
1264 	dst.addr = daddr;
1265 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1266 	dst.scope = __ipv6_addr_src_scope(dst_type);
1267 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1268 	dst.prefs = prefs;
1269 
1270 	hiscore->rule = -1;
1271 	hiscore->ifa = NULL;
1272 
1273 	rcu_read_lock();
1274 
1275 	for_each_netdev_rcu(net, dev) {
1276 		struct inet6_dev *idev;
1277 
1278 		/* Candidate Source Address (section 4)
1279 		 *  - multicast and link-local destination address,
1280 		 *    the set of candidate source address MUST only
1281 		 *    include addresses assigned to interfaces
1282 		 *    belonging to the same link as the outgoing
1283 		 *    interface.
1284 		 * (- For site-local destination addresses, the
1285 		 *    set of candidate source addresses MUST only
1286 		 *    include addresses assigned to interfaces
1287 		 *    belonging to the same site as the outgoing
1288 		 *    interface.)
1289 		 */
1290 		if (((dst_type & IPV6_ADDR_MULTICAST) ||
1291 		     dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL) &&
1292 		    dst.ifindex && dev->ifindex != dst.ifindex)
1293 			continue;
1294 
1295 		idev = __in6_dev_get(dev);
1296 		if (!idev)
1297 			continue;
1298 
1299 		read_lock_bh(&idev->lock);
1300 		list_for_each_entry(score->ifa, &idev->addr_list, if_list) {
1301 			int i;
1302 
1303 			/*
1304 			 * - Tentative Address (RFC2462 section 5.4)
1305 			 *  - A tentative address is not considered
1306 			 *    "assigned to an interface" in the traditional
1307 			 *    sense, unless it is also flagged as optimistic.
1308 			 * - Candidate Source Address (section 4)
1309 			 *  - In any case, anycast addresses, multicast
1310 			 *    addresses, and the unspecified address MUST
1311 			 *    NOT be included in a candidate set.
1312 			 */
1313 			if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1314 			    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1315 				continue;
1316 
1317 			score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1318 
1319 			if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1320 				     score->addr_type & IPV6_ADDR_MULTICAST)) {
1321 				LIMIT_NETDEBUG(KERN_DEBUG
1322 					       "ADDRCONF: unspecified / multicast address "
1323 					       "assigned as unicast address on %s",
1324 					       dev->name);
1325 				continue;
1326 			}
1327 
1328 			score->rule = -1;
1329 			bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1330 
1331 			for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1332 				int minihiscore, miniscore;
1333 
1334 				minihiscore = ipv6_get_saddr_eval(net, hiscore, &dst, i);
1335 				miniscore = ipv6_get_saddr_eval(net, score, &dst, i);
1336 
1337 				if (minihiscore > miniscore) {
1338 					if (i == IPV6_SADDR_RULE_SCOPE &&
1339 					    score->scopedist > 0) {
1340 						/*
1341 						 * special case:
1342 						 * each remaining entry
1343 						 * has too small (not enough)
1344 						 * scope, because ifa entries
1345 						 * are sorted by their scope
1346 						 * values.
1347 						 */
1348 						goto try_nextdev;
1349 					}
1350 					break;
1351 				} else if (minihiscore < miniscore) {
1352 					if (hiscore->ifa)
1353 						in6_ifa_put(hiscore->ifa);
1354 
1355 					in6_ifa_hold(score->ifa);
1356 
1357 					swap(hiscore, score);
1358 
1359 					/* restore our iterator */
1360 					score->ifa = hiscore->ifa;
1361 
1362 					break;
1363 				}
1364 			}
1365 		}
1366 try_nextdev:
1367 		read_unlock_bh(&idev->lock);
1368 	}
1369 	rcu_read_unlock();
1370 
1371 	if (!hiscore->ifa)
1372 		return -EADDRNOTAVAIL;
1373 
1374 	*saddr = hiscore->ifa->addr;
1375 	in6_ifa_put(hiscore->ifa);
1376 	return 0;
1377 }
1378 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1379 
1380 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1381 		    unsigned char banned_flags)
1382 {
1383 	struct inet6_dev *idev;
1384 	int err = -EADDRNOTAVAIL;
1385 
1386 	rcu_read_lock();
1387 	idev = __in6_dev_get(dev);
1388 	if (idev) {
1389 		struct inet6_ifaddr *ifp;
1390 
1391 		read_lock_bh(&idev->lock);
1392 		list_for_each_entry(ifp, &idev->addr_list, if_list) {
1393 			if (ifp->scope == IFA_LINK &&
1394 			    !(ifp->flags & banned_flags)) {
1395 				*addr = ifp->addr;
1396 				err = 0;
1397 				break;
1398 			}
1399 		}
1400 		read_unlock_bh(&idev->lock);
1401 	}
1402 	rcu_read_unlock();
1403 	return err;
1404 }
1405 
1406 static int ipv6_count_addresses(struct inet6_dev *idev)
1407 {
1408 	int cnt = 0;
1409 	struct inet6_ifaddr *ifp;
1410 
1411 	read_lock_bh(&idev->lock);
1412 	list_for_each_entry(ifp, &idev->addr_list, if_list)
1413 		cnt++;
1414 	read_unlock_bh(&idev->lock);
1415 	return cnt;
1416 }
1417 
1418 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1419 		  struct net_device *dev, int strict)
1420 {
1421 	struct inet6_ifaddr *ifp;
1422 	unsigned int hash = inet6_addr_hash(addr);
1423 
1424 	rcu_read_lock_bh();
1425 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
1426 		if (!net_eq(dev_net(ifp->idev->dev), net))
1427 			continue;
1428 		if (ipv6_addr_equal(&ifp->addr, addr) &&
1429 		    !(ifp->flags&IFA_F_TENTATIVE) &&
1430 		    (dev == NULL || ifp->idev->dev == dev ||
1431 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1432 			rcu_read_unlock_bh();
1433 			return 1;
1434 		}
1435 	}
1436 
1437 	rcu_read_unlock_bh();
1438 	return 0;
1439 }
1440 EXPORT_SYMBOL(ipv6_chk_addr);
1441 
1442 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
1443 			       struct net_device *dev)
1444 {
1445 	unsigned int hash = inet6_addr_hash(addr);
1446 	struct inet6_ifaddr *ifp;
1447 
1448 	hlist_for_each_entry(ifp, &inet6_addr_lst[hash], addr_lst) {
1449 		if (!net_eq(dev_net(ifp->idev->dev), net))
1450 			continue;
1451 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1452 			if (dev == NULL || ifp->idev->dev == dev)
1453 				return true;
1454 		}
1455 	}
1456 	return false;
1457 }
1458 
1459 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
1460 {
1461 	struct inet6_dev *idev;
1462 	struct inet6_ifaddr *ifa;
1463 	int	onlink;
1464 
1465 	onlink = 0;
1466 	rcu_read_lock();
1467 	idev = __in6_dev_get(dev);
1468 	if (idev) {
1469 		read_lock_bh(&idev->lock);
1470 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
1471 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
1472 						   ifa->prefix_len);
1473 			if (onlink)
1474 				break;
1475 		}
1476 		read_unlock_bh(&idev->lock);
1477 	}
1478 	rcu_read_unlock();
1479 	return onlink;
1480 }
1481 EXPORT_SYMBOL(ipv6_chk_prefix);
1482 
1483 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
1484 				     struct net_device *dev, int strict)
1485 {
1486 	struct inet6_ifaddr *ifp, *result = NULL;
1487 	unsigned int hash = inet6_addr_hash(addr);
1488 
1489 	rcu_read_lock_bh();
1490 	hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[hash], addr_lst) {
1491 		if (!net_eq(dev_net(ifp->idev->dev), net))
1492 			continue;
1493 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1494 			if (dev == NULL || ifp->idev->dev == dev ||
1495 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
1496 				result = ifp;
1497 				in6_ifa_hold(ifp);
1498 				break;
1499 			}
1500 		}
1501 	}
1502 	rcu_read_unlock_bh();
1503 
1504 	return result;
1505 }
1506 
1507 /* Gets referenced address, destroys ifaddr */
1508 
1509 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
1510 {
1511 	if (ifp->flags&IFA_F_PERMANENT) {
1512 		spin_lock_bh(&ifp->lock);
1513 		addrconf_del_timer(ifp);
1514 		ifp->flags |= IFA_F_TENTATIVE;
1515 		if (dad_failed)
1516 			ifp->flags |= IFA_F_DADFAILED;
1517 		spin_unlock_bh(&ifp->lock);
1518 		if (dad_failed)
1519 			ipv6_ifa_notify(0, ifp);
1520 		in6_ifa_put(ifp);
1521 #ifdef CONFIG_IPV6_PRIVACY
1522 	} else if (ifp->flags&IFA_F_TEMPORARY) {
1523 		struct inet6_ifaddr *ifpub;
1524 		spin_lock_bh(&ifp->lock);
1525 		ifpub = ifp->ifpub;
1526 		if (ifpub) {
1527 			in6_ifa_hold(ifpub);
1528 			spin_unlock_bh(&ifp->lock);
1529 			ipv6_create_tempaddr(ifpub, ifp);
1530 			in6_ifa_put(ifpub);
1531 		} else {
1532 			spin_unlock_bh(&ifp->lock);
1533 		}
1534 		ipv6_del_addr(ifp);
1535 #endif
1536 	} else
1537 		ipv6_del_addr(ifp);
1538 }
1539 
1540 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
1541 {
1542 	int err = -ENOENT;
1543 
1544 	spin_lock(&ifp->state_lock);
1545 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
1546 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
1547 		err = 0;
1548 	}
1549 	spin_unlock(&ifp->state_lock);
1550 
1551 	return err;
1552 }
1553 
1554 void addrconf_dad_failure(struct inet6_ifaddr *ifp)
1555 {
1556 	struct inet6_dev *idev = ifp->idev;
1557 
1558 	if (addrconf_dad_end(ifp)) {
1559 		in6_ifa_put(ifp);
1560 		return;
1561 	}
1562 
1563 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c detected!\n",
1564 			     ifp->idev->dev->name, &ifp->addr);
1565 
1566 	if (idev->cnf.accept_dad > 1 && !idev->cnf.disable_ipv6) {
1567 		struct in6_addr addr;
1568 
1569 		addr.s6_addr32[0] = htonl(0xfe800000);
1570 		addr.s6_addr32[1] = 0;
1571 
1572 		if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
1573 		    ipv6_addr_equal(&ifp->addr, &addr)) {
1574 			/* DAD failed for link-local based on MAC address */
1575 			idev->cnf.disable_ipv6 = 1;
1576 
1577 			pr_info("%s: IPv6 being disabled!\n",
1578 				ifp->idev->dev->name);
1579 		}
1580 	}
1581 
1582 	addrconf_dad_stop(ifp, 1);
1583 }
1584 
1585 /* Join to solicited addr multicast group. */
1586 
1587 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
1588 {
1589 	struct in6_addr maddr;
1590 
1591 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
1592 		return;
1593 
1594 	addrconf_addr_solict_mult(addr, &maddr);
1595 	ipv6_dev_mc_inc(dev, &maddr);
1596 }
1597 
1598 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
1599 {
1600 	struct in6_addr maddr;
1601 
1602 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
1603 		return;
1604 
1605 	addrconf_addr_solict_mult(addr, &maddr);
1606 	__ipv6_dev_mc_dec(idev, &maddr);
1607 }
1608 
1609 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
1610 {
1611 	struct in6_addr addr;
1612 	if (ifp->prefix_len == 127) /* RFC 6164 */
1613 		return;
1614 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
1615 	if (ipv6_addr_any(&addr))
1616 		return;
1617 	ipv6_dev_ac_inc(ifp->idev->dev, &addr);
1618 }
1619 
1620 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
1621 {
1622 	struct in6_addr addr;
1623 	if (ifp->prefix_len == 127) /* RFC 6164 */
1624 		return;
1625 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
1626 	if (ipv6_addr_any(&addr))
1627 		return;
1628 	__ipv6_dev_ac_dec(ifp->idev, &addr);
1629 }
1630 
1631 static int addrconf_ifid_eui48(u8 *eui, struct net_device *dev)
1632 {
1633 	if (dev->addr_len != ETH_ALEN)
1634 		return -1;
1635 	memcpy(eui, dev->dev_addr, 3);
1636 	memcpy(eui + 5, dev->dev_addr + 3, 3);
1637 
1638 	/*
1639 	 * The zSeries OSA network cards can be shared among various
1640 	 * OS instances, but the OSA cards have only one MAC address.
1641 	 * This leads to duplicate address conflicts in conjunction
1642 	 * with IPv6 if more than one instance uses the same card.
1643 	 *
1644 	 * The driver for these cards can deliver a unique 16-bit
1645 	 * identifier for each instance sharing the same card.  It is
1646 	 * placed instead of 0xFFFE in the interface identifier.  The
1647 	 * "u" bit of the interface identifier is not inverted in this
1648 	 * case.  Hence the resulting interface identifier has local
1649 	 * scope according to RFC2373.
1650 	 */
1651 	if (dev->dev_id) {
1652 		eui[3] = (dev->dev_id >> 8) & 0xFF;
1653 		eui[4] = dev->dev_id & 0xFF;
1654 	} else {
1655 		eui[3] = 0xFF;
1656 		eui[4] = 0xFE;
1657 		eui[0] ^= 2;
1658 	}
1659 	return 0;
1660 }
1661 
1662 static int addrconf_ifid_eui64(u8 *eui, struct net_device *dev)
1663 {
1664 	if (dev->addr_len != IEEE802154_ADDR_LEN)
1665 		return -1;
1666 	memcpy(eui, dev->dev_addr, 8);
1667 	eui[0] ^= 2;
1668 	return 0;
1669 }
1670 
1671 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
1672 {
1673 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
1674 	if (dev->addr_len != ARCNET_ALEN)
1675 		return -1;
1676 	memset(eui, 0, 7);
1677 	eui[7] = *(u8 *)dev->dev_addr;
1678 	return 0;
1679 }
1680 
1681 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
1682 {
1683 	if (dev->addr_len != INFINIBAND_ALEN)
1684 		return -1;
1685 	memcpy(eui, dev->dev_addr + 12, 8);
1686 	eui[0] |= 2;
1687 	return 0;
1688 }
1689 
1690 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
1691 {
1692 	if (addr == 0)
1693 		return -1;
1694 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
1695 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
1696 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
1697 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
1698 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
1699 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
1700 	eui[1] = 0;
1701 	eui[2] = 0x5E;
1702 	eui[3] = 0xFE;
1703 	memcpy(eui + 4, &addr, 4);
1704 	return 0;
1705 }
1706 
1707 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
1708 {
1709 	if (dev->priv_flags & IFF_ISATAP)
1710 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
1711 	return -1;
1712 }
1713 
1714 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
1715 {
1716 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
1717 }
1718 
1719 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
1720 {
1721 	switch (dev->type) {
1722 	case ARPHRD_ETHER:
1723 	case ARPHRD_FDDI:
1724 		return addrconf_ifid_eui48(eui, dev);
1725 	case ARPHRD_ARCNET:
1726 		return addrconf_ifid_arcnet(eui, dev);
1727 	case ARPHRD_INFINIBAND:
1728 		return addrconf_ifid_infiniband(eui, dev);
1729 	case ARPHRD_SIT:
1730 		return addrconf_ifid_sit(eui, dev);
1731 	case ARPHRD_IPGRE:
1732 		return addrconf_ifid_gre(eui, dev);
1733 	case ARPHRD_IEEE802154:
1734 		return addrconf_ifid_eui64(eui, dev);
1735 	}
1736 	return -1;
1737 }
1738 
1739 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
1740 {
1741 	int err = -1;
1742 	struct inet6_ifaddr *ifp;
1743 
1744 	read_lock_bh(&idev->lock);
1745 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
1746 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
1747 			memcpy(eui, ifp->addr.s6_addr+8, 8);
1748 			err = 0;
1749 			break;
1750 		}
1751 	}
1752 	read_unlock_bh(&idev->lock);
1753 	return err;
1754 }
1755 
1756 #ifdef CONFIG_IPV6_PRIVACY
1757 /* (re)generation of randomized interface identifier (RFC 3041 3.2, 3.5) */
1758 static void __ipv6_regen_rndid(struct inet6_dev *idev)
1759 {
1760 regen:
1761 	get_random_bytes(idev->rndid, sizeof(idev->rndid));
1762 	idev->rndid[0] &= ~0x02;
1763 
1764 	/*
1765 	 * <draft-ietf-ipngwg-temp-addresses-v2-00.txt>:
1766 	 * check if generated address is not inappropriate
1767 	 *
1768 	 *  - Reserved subnet anycast (RFC 2526)
1769 	 *	11111101 11....11 1xxxxxxx
1770 	 *  - ISATAP (RFC4214) 6.1
1771 	 *	00-00-5E-FE-xx-xx-xx-xx
1772 	 *  - value 0
1773 	 *  - XXX: already assigned to an address on the device
1774 	 */
1775 	if (idev->rndid[0] == 0xfd &&
1776 	    (idev->rndid[1]&idev->rndid[2]&idev->rndid[3]&idev->rndid[4]&idev->rndid[5]&idev->rndid[6]) == 0xff &&
1777 	    (idev->rndid[7]&0x80))
1778 		goto regen;
1779 	if ((idev->rndid[0]|idev->rndid[1]) == 0) {
1780 		if (idev->rndid[2] == 0x5e && idev->rndid[3] == 0xfe)
1781 			goto regen;
1782 		if ((idev->rndid[2]|idev->rndid[3]|idev->rndid[4]|idev->rndid[5]|idev->rndid[6]|idev->rndid[7]) == 0x00)
1783 			goto regen;
1784 	}
1785 }
1786 
1787 static void ipv6_regen_rndid(unsigned long data)
1788 {
1789 	struct inet6_dev *idev = (struct inet6_dev *) data;
1790 	unsigned long expires;
1791 
1792 	rcu_read_lock_bh();
1793 	write_lock_bh(&idev->lock);
1794 
1795 	if (idev->dead)
1796 		goto out;
1797 
1798 	__ipv6_regen_rndid(idev);
1799 
1800 	expires = jiffies +
1801 		idev->cnf.temp_prefered_lft * HZ -
1802 		idev->cnf.regen_max_retry * idev->cnf.dad_transmits * idev->nd_parms->retrans_time -
1803 		idev->cnf.max_desync_factor * HZ;
1804 	if (time_before(expires, jiffies)) {
1805 		pr_warn("%s: too short regeneration interval; timer disabled for %s\n",
1806 			__func__, idev->dev->name);
1807 		goto out;
1808 	}
1809 
1810 	if (!mod_timer(&idev->regen_timer, expires))
1811 		in6_dev_hold(idev);
1812 
1813 out:
1814 	write_unlock_bh(&idev->lock);
1815 	rcu_read_unlock_bh();
1816 	in6_dev_put(idev);
1817 }
1818 
1819 static void  __ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr)
1820 {
1821 	if (tmpaddr && memcmp(idev->rndid, &tmpaddr->s6_addr[8], 8) == 0)
1822 		__ipv6_regen_rndid(idev);
1823 }
1824 #endif
1825 
1826 /*
1827  *	Add prefix route.
1828  */
1829 
1830 static void
1831 addrconf_prefix_route(struct in6_addr *pfx, int plen, struct net_device *dev,
1832 		      unsigned long expires, u32 flags)
1833 {
1834 	struct fib6_config cfg = {
1835 		.fc_table = RT6_TABLE_PREFIX,
1836 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
1837 		.fc_ifindex = dev->ifindex,
1838 		.fc_expires = expires,
1839 		.fc_dst_len = plen,
1840 		.fc_flags = RTF_UP | flags,
1841 		.fc_nlinfo.nl_net = dev_net(dev),
1842 		.fc_protocol = RTPROT_KERNEL,
1843 	};
1844 
1845 	cfg.fc_dst = *pfx;
1846 
1847 	/* Prevent useless cloning on PtP SIT.
1848 	   This thing is done here expecting that the whole
1849 	   class of non-broadcast devices need not cloning.
1850 	 */
1851 #if IS_ENABLED(CONFIG_IPV6_SIT)
1852 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
1853 		cfg.fc_flags |= RTF_NONEXTHOP;
1854 #endif
1855 
1856 	ip6_route_add(&cfg);
1857 }
1858 
1859 
1860 static struct rt6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
1861 						  int plen,
1862 						  const struct net_device *dev,
1863 						  u32 flags, u32 noflags)
1864 {
1865 	struct fib6_node *fn;
1866 	struct rt6_info *rt = NULL;
1867 	struct fib6_table *table;
1868 
1869 	table = fib6_get_table(dev_net(dev), RT6_TABLE_PREFIX);
1870 	if (table == NULL)
1871 		return NULL;
1872 
1873 	read_lock_bh(&table->tb6_lock);
1874 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0);
1875 	if (!fn)
1876 		goto out;
1877 	for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
1878 		if (rt->dst.dev->ifindex != dev->ifindex)
1879 			continue;
1880 		if ((rt->rt6i_flags & flags) != flags)
1881 			continue;
1882 		if ((rt->rt6i_flags & noflags) != 0)
1883 			continue;
1884 		dst_hold(&rt->dst);
1885 		break;
1886 	}
1887 out:
1888 	read_unlock_bh(&table->tb6_lock);
1889 	return rt;
1890 }
1891 
1892 
1893 /* Create "default" multicast route to the interface */
1894 
1895 static void addrconf_add_mroute(struct net_device *dev)
1896 {
1897 	struct fib6_config cfg = {
1898 		.fc_table = RT6_TABLE_LOCAL,
1899 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
1900 		.fc_ifindex = dev->ifindex,
1901 		.fc_dst_len = 8,
1902 		.fc_flags = RTF_UP,
1903 		.fc_nlinfo.nl_net = dev_net(dev),
1904 	};
1905 
1906 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
1907 
1908 	ip6_route_add(&cfg);
1909 }
1910 
1911 #if IS_ENABLED(CONFIG_IPV6_SIT)
1912 static void sit_route_add(struct net_device *dev)
1913 {
1914 	struct fib6_config cfg = {
1915 		.fc_table = RT6_TABLE_MAIN,
1916 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
1917 		.fc_ifindex = dev->ifindex,
1918 		.fc_dst_len = 96,
1919 		.fc_flags = RTF_UP | RTF_NONEXTHOP,
1920 		.fc_nlinfo.nl_net = dev_net(dev),
1921 	};
1922 
1923 	/* prefix length - 96 bits "::d.d.d.d" */
1924 	ip6_route_add(&cfg);
1925 }
1926 #endif
1927 
1928 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
1929 {
1930 	struct inet6_dev *idev;
1931 
1932 	ASSERT_RTNL();
1933 
1934 	idev = ipv6_find_idev(dev);
1935 	if (!idev)
1936 		return ERR_PTR(-ENOBUFS);
1937 
1938 	if (idev->cnf.disable_ipv6)
1939 		return ERR_PTR(-EACCES);
1940 
1941 	/* Add default multicast route */
1942 	if (!(dev->flags & IFF_LOOPBACK))
1943 		addrconf_add_mroute(dev);
1944 
1945 	return idev;
1946 }
1947 
1948 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
1949 {
1950 	struct prefix_info *pinfo;
1951 	__u32 valid_lft;
1952 	__u32 prefered_lft;
1953 	int addr_type;
1954 	struct inet6_dev *in6_dev;
1955 	struct net *net = dev_net(dev);
1956 
1957 	pinfo = (struct prefix_info *) opt;
1958 
1959 	if (len < sizeof(struct prefix_info)) {
1960 		ADBG(("addrconf: prefix option too short\n"));
1961 		return;
1962 	}
1963 
1964 	/*
1965 	 *	Validation checks ([ADDRCONF], page 19)
1966 	 */
1967 
1968 	addr_type = ipv6_addr_type(&pinfo->prefix);
1969 
1970 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
1971 		return;
1972 
1973 	valid_lft = ntohl(pinfo->valid);
1974 	prefered_lft = ntohl(pinfo->prefered);
1975 
1976 	if (prefered_lft > valid_lft) {
1977 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
1978 		return;
1979 	}
1980 
1981 	in6_dev = in6_dev_get(dev);
1982 
1983 	if (in6_dev == NULL) {
1984 		net_dbg_ratelimited("addrconf: device %s not configured\n",
1985 				    dev->name);
1986 		return;
1987 	}
1988 
1989 	/*
1990 	 *	Two things going on here:
1991 	 *	1) Add routes for on-link prefixes
1992 	 *	2) Configure prefixes with the auto flag set
1993 	 */
1994 
1995 	if (pinfo->onlink) {
1996 		struct rt6_info *rt;
1997 		unsigned long rt_expires;
1998 
1999 		/* Avoid arithmetic overflow. Really, we could
2000 		 * save rt_expires in seconds, likely valid_lft,
2001 		 * but it would require division in fib gc, that it
2002 		 * not good.
2003 		 */
2004 		if (HZ > USER_HZ)
2005 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2006 		else
2007 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2008 
2009 		if (addrconf_finite_timeout(rt_expires))
2010 			rt_expires *= HZ;
2011 
2012 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2013 					       pinfo->prefix_len,
2014 					       dev,
2015 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2016 					       RTF_GATEWAY | RTF_DEFAULT);
2017 
2018 		if (rt) {
2019 			/* Autoconf prefix route */
2020 			if (valid_lft == 0) {
2021 				ip6_del_rt(rt);
2022 				rt = NULL;
2023 			} else if (addrconf_finite_timeout(rt_expires)) {
2024 				/* not infinity */
2025 				rt6_set_expires(rt, jiffies + rt_expires);
2026 			} else {
2027 				rt6_clean_expires(rt);
2028 			}
2029 		} else if (valid_lft) {
2030 			clock_t expires = 0;
2031 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2032 			if (addrconf_finite_timeout(rt_expires)) {
2033 				/* not infinity */
2034 				flags |= RTF_EXPIRES;
2035 				expires = jiffies_to_clock_t(rt_expires);
2036 			}
2037 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2038 					      dev, expires, flags);
2039 		}
2040 		ip6_rt_put(rt);
2041 	}
2042 
2043 	/* Try to figure out our local address for this prefix */
2044 
2045 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
2046 		struct inet6_ifaddr *ifp;
2047 		struct in6_addr addr;
2048 		int create = 0, update_lft = 0;
2049 
2050 		if (pinfo->prefix_len == 64) {
2051 			memcpy(&addr, &pinfo->prefix, 8);
2052 			if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2053 			    ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2054 				in6_dev_put(in6_dev);
2055 				return;
2056 			}
2057 			goto ok;
2058 		}
2059 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2060 				    pinfo->prefix_len);
2061 		in6_dev_put(in6_dev);
2062 		return;
2063 
2064 ok:
2065 
2066 		ifp = ipv6_get_ifaddr(net, &addr, dev, 1);
2067 
2068 		if (ifp == NULL && valid_lft) {
2069 			int max_addresses = in6_dev->cnf.max_addresses;
2070 			u32 addr_flags = 0;
2071 
2072 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2073 			if (in6_dev->cnf.optimistic_dad &&
2074 			    !net->ipv6.devconf_all->forwarding && sllao)
2075 				addr_flags = IFA_F_OPTIMISTIC;
2076 #endif
2077 
2078 			/* Do not allow to create too much of autoconfigured
2079 			 * addresses; this would be too easy way to crash kernel.
2080 			 */
2081 			if (!max_addresses ||
2082 			    ipv6_count_addresses(in6_dev) < max_addresses)
2083 				ifp = ipv6_add_addr(in6_dev, &addr, pinfo->prefix_len,
2084 						    addr_type&IPV6_ADDR_SCOPE_MASK,
2085 						    addr_flags);
2086 
2087 			if (IS_ERR_OR_NULL(ifp)) {
2088 				in6_dev_put(in6_dev);
2089 				return;
2090 			}
2091 
2092 			update_lft = create = 1;
2093 			ifp->cstamp = jiffies;
2094 			addrconf_dad_start(ifp);
2095 		}
2096 
2097 		if (ifp) {
2098 			int flags;
2099 			unsigned long now;
2100 #ifdef CONFIG_IPV6_PRIVACY
2101 			struct inet6_ifaddr *ift;
2102 #endif
2103 			u32 stored_lft;
2104 
2105 			/* update lifetime (RFC2462 5.5.3 e) */
2106 			spin_lock(&ifp->lock);
2107 			now = jiffies;
2108 			if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2109 				stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2110 			else
2111 				stored_lft = 0;
2112 			if (!update_lft && stored_lft) {
2113 				if (valid_lft > MIN_VALID_LIFETIME ||
2114 				    valid_lft > stored_lft)
2115 					update_lft = 1;
2116 				else if (stored_lft <= MIN_VALID_LIFETIME) {
2117 					/* valid_lft <= stored_lft is always true */
2118 					/*
2119 					 * RFC 4862 Section 5.5.3e:
2120 					 * "Note that the preferred lifetime of
2121 					 *  the corresponding address is always
2122 					 *  reset to the Preferred Lifetime in
2123 					 *  the received Prefix Information
2124 					 *  option, regardless of whether the
2125 					 *  valid lifetime is also reset or
2126 					 *  ignored."
2127 					 *
2128 					 *  So if the preferred lifetime in
2129 					 *  this advertisement is different
2130 					 *  than what we have stored, but the
2131 					 *  valid lifetime is invalid, just
2132 					 *  reset prefered_lft.
2133 					 *
2134 					 *  We must set the valid lifetime
2135 					 *  to the stored lifetime since we'll
2136 					 *  be updating the timestamp below,
2137 					 *  else we'll set it back to the
2138 					 *  minimum.
2139 					 */
2140 					if (prefered_lft != ifp->prefered_lft) {
2141 						valid_lft = stored_lft;
2142 						update_lft = 1;
2143 					}
2144 				} else {
2145 					valid_lft = MIN_VALID_LIFETIME;
2146 					if (valid_lft < prefered_lft)
2147 						prefered_lft = valid_lft;
2148 					update_lft = 1;
2149 				}
2150 			}
2151 
2152 			if (update_lft) {
2153 				ifp->valid_lft = valid_lft;
2154 				ifp->prefered_lft = prefered_lft;
2155 				ifp->tstamp = now;
2156 				flags = ifp->flags;
2157 				ifp->flags &= ~IFA_F_DEPRECATED;
2158 				spin_unlock(&ifp->lock);
2159 
2160 				if (!(flags&IFA_F_TENTATIVE))
2161 					ipv6_ifa_notify(0, ifp);
2162 			} else
2163 				spin_unlock(&ifp->lock);
2164 
2165 #ifdef CONFIG_IPV6_PRIVACY
2166 			read_lock_bh(&in6_dev->lock);
2167 			/* update all temporary addresses in the list */
2168 			list_for_each_entry(ift, &in6_dev->tempaddr_list,
2169 					    tmp_list) {
2170 				int age, max_valid, max_prefered;
2171 
2172 				if (ifp != ift->ifpub)
2173 					continue;
2174 
2175 				/*
2176 				 * RFC 4941 section 3.3:
2177 				 * If a received option will extend the lifetime
2178 				 * of a public address, the lifetimes of
2179 				 * temporary addresses should be extended,
2180 				 * subject to the overall constraint that no
2181 				 * temporary addresses should ever remain
2182 				 * "valid" or "preferred" for a time longer than
2183 				 * (TEMP_VALID_LIFETIME) or
2184 				 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR),
2185 				 * respectively.
2186 				 */
2187 				age = (now - ift->cstamp) / HZ;
2188 				max_valid = in6_dev->cnf.temp_valid_lft - age;
2189 				if (max_valid < 0)
2190 					max_valid = 0;
2191 
2192 				max_prefered = in6_dev->cnf.temp_prefered_lft -
2193 					       in6_dev->cnf.max_desync_factor -
2194 					       age;
2195 				if (max_prefered < 0)
2196 					max_prefered = 0;
2197 
2198 				if (valid_lft > max_valid)
2199 					valid_lft = max_valid;
2200 
2201 				if (prefered_lft > max_prefered)
2202 					prefered_lft = max_prefered;
2203 
2204 				spin_lock(&ift->lock);
2205 				flags = ift->flags;
2206 				ift->valid_lft = valid_lft;
2207 				ift->prefered_lft = prefered_lft;
2208 				ift->tstamp = now;
2209 				if (prefered_lft > 0)
2210 					ift->flags &= ~IFA_F_DEPRECATED;
2211 
2212 				spin_unlock(&ift->lock);
2213 				if (!(flags&IFA_F_TENTATIVE))
2214 					ipv6_ifa_notify(0, ift);
2215 			}
2216 
2217 			if ((create || list_empty(&in6_dev->tempaddr_list)) && in6_dev->cnf.use_tempaddr > 0) {
2218 				/*
2219 				 * When a new public address is created as
2220 				 * described in [ADDRCONF], also create a new
2221 				 * temporary address. Also create a temporary
2222 				 * address if it's enabled but no temporary
2223 				 * address currently exists.
2224 				 */
2225 				read_unlock_bh(&in6_dev->lock);
2226 				ipv6_create_tempaddr(ifp, NULL);
2227 			} else {
2228 				read_unlock_bh(&in6_dev->lock);
2229 			}
2230 #endif
2231 			in6_ifa_put(ifp);
2232 			addrconf_verify(0);
2233 		}
2234 	}
2235 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2236 	in6_dev_put(in6_dev);
2237 }
2238 
2239 /*
2240  *	Set destination address.
2241  *	Special case for SIT interfaces where we create a new "virtual"
2242  *	device.
2243  */
2244 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2245 {
2246 	struct in6_ifreq ireq;
2247 	struct net_device *dev;
2248 	int err = -EINVAL;
2249 
2250 	rtnl_lock();
2251 
2252 	err = -EFAULT;
2253 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2254 		goto err_exit;
2255 
2256 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2257 
2258 	err = -ENODEV;
2259 	if (dev == NULL)
2260 		goto err_exit;
2261 
2262 #if IS_ENABLED(CONFIG_IPV6_SIT)
2263 	if (dev->type == ARPHRD_SIT) {
2264 		const struct net_device_ops *ops = dev->netdev_ops;
2265 		struct ifreq ifr;
2266 		struct ip_tunnel_parm p;
2267 
2268 		err = -EADDRNOTAVAIL;
2269 		if (!(ipv6_addr_type(&ireq.ifr6_addr) & IPV6_ADDR_COMPATv4))
2270 			goto err_exit;
2271 
2272 		memset(&p, 0, sizeof(p));
2273 		p.iph.daddr = ireq.ifr6_addr.s6_addr32[3];
2274 		p.iph.saddr = 0;
2275 		p.iph.version = 4;
2276 		p.iph.ihl = 5;
2277 		p.iph.protocol = IPPROTO_IPV6;
2278 		p.iph.ttl = 64;
2279 		ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
2280 
2281 		if (ops->ndo_do_ioctl) {
2282 			mm_segment_t oldfs = get_fs();
2283 
2284 			set_fs(KERNEL_DS);
2285 			err = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
2286 			set_fs(oldfs);
2287 		} else
2288 			err = -EOPNOTSUPP;
2289 
2290 		if (err == 0) {
2291 			err = -ENOBUFS;
2292 			dev = __dev_get_by_name(net, p.name);
2293 			if (!dev)
2294 				goto err_exit;
2295 			err = dev_open(dev);
2296 		}
2297 	}
2298 #endif
2299 
2300 err_exit:
2301 	rtnl_unlock();
2302 	return err;
2303 }
2304 
2305 /*
2306  *	Manual configuration of address on an interface
2307  */
2308 static int inet6_addr_add(struct net *net, int ifindex, const struct in6_addr *pfx,
2309 			  unsigned int plen, __u8 ifa_flags, __u32 prefered_lft,
2310 			  __u32 valid_lft)
2311 {
2312 	struct inet6_ifaddr *ifp;
2313 	struct inet6_dev *idev;
2314 	struct net_device *dev;
2315 	int scope;
2316 	u32 flags;
2317 	clock_t expires;
2318 	unsigned long timeout;
2319 
2320 	ASSERT_RTNL();
2321 
2322 	if (plen > 128)
2323 		return -EINVAL;
2324 
2325 	/* check the lifetime */
2326 	if (!valid_lft || prefered_lft > valid_lft)
2327 		return -EINVAL;
2328 
2329 	dev = __dev_get_by_index(net, ifindex);
2330 	if (!dev)
2331 		return -ENODEV;
2332 
2333 	idev = addrconf_add_dev(dev);
2334 	if (IS_ERR(idev))
2335 		return PTR_ERR(idev);
2336 
2337 	scope = ipv6_addr_scope(pfx);
2338 
2339 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
2340 	if (addrconf_finite_timeout(timeout)) {
2341 		expires = jiffies_to_clock_t(timeout * HZ);
2342 		valid_lft = timeout;
2343 		flags = RTF_EXPIRES;
2344 	} else {
2345 		expires = 0;
2346 		flags = 0;
2347 		ifa_flags |= IFA_F_PERMANENT;
2348 	}
2349 
2350 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
2351 	if (addrconf_finite_timeout(timeout)) {
2352 		if (timeout == 0)
2353 			ifa_flags |= IFA_F_DEPRECATED;
2354 		prefered_lft = timeout;
2355 	}
2356 
2357 	ifp = ipv6_add_addr(idev, pfx, plen, scope, ifa_flags);
2358 
2359 	if (!IS_ERR(ifp)) {
2360 		spin_lock_bh(&ifp->lock);
2361 		ifp->valid_lft = valid_lft;
2362 		ifp->prefered_lft = prefered_lft;
2363 		ifp->tstamp = jiffies;
2364 		spin_unlock_bh(&ifp->lock);
2365 
2366 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, dev,
2367 				      expires, flags);
2368 		/*
2369 		 * Note that section 3.1 of RFC 4429 indicates
2370 		 * that the Optimistic flag should not be set for
2371 		 * manually configured addresses
2372 		 */
2373 		addrconf_dad_start(ifp);
2374 		in6_ifa_put(ifp);
2375 		addrconf_verify(0);
2376 		return 0;
2377 	}
2378 
2379 	return PTR_ERR(ifp);
2380 }
2381 
2382 static int inet6_addr_del(struct net *net, int ifindex, const struct in6_addr *pfx,
2383 			  unsigned int plen)
2384 {
2385 	struct inet6_ifaddr *ifp;
2386 	struct inet6_dev *idev;
2387 	struct net_device *dev;
2388 
2389 	if (plen > 128)
2390 		return -EINVAL;
2391 
2392 	dev = __dev_get_by_index(net, ifindex);
2393 	if (!dev)
2394 		return -ENODEV;
2395 
2396 	if ((idev = __in6_dev_get(dev)) == NULL)
2397 		return -ENXIO;
2398 
2399 	read_lock_bh(&idev->lock);
2400 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
2401 		if (ifp->prefix_len == plen &&
2402 		    ipv6_addr_equal(pfx, &ifp->addr)) {
2403 			in6_ifa_hold(ifp);
2404 			read_unlock_bh(&idev->lock);
2405 
2406 			ipv6_del_addr(ifp);
2407 
2408 			/* If the last address is deleted administratively,
2409 			   disable IPv6 on this interface.
2410 			 */
2411 			if (list_empty(&idev->addr_list))
2412 				addrconf_ifdown(idev->dev, 1);
2413 			return 0;
2414 		}
2415 	}
2416 	read_unlock_bh(&idev->lock);
2417 	return -EADDRNOTAVAIL;
2418 }
2419 
2420 
2421 int addrconf_add_ifaddr(struct net *net, void __user *arg)
2422 {
2423 	struct in6_ifreq ireq;
2424 	int err;
2425 
2426 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2427 		return -EPERM;
2428 
2429 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2430 		return -EFAULT;
2431 
2432 	rtnl_lock();
2433 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &ireq.ifr6_addr,
2434 			     ireq.ifr6_prefixlen, IFA_F_PERMANENT,
2435 			     INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
2436 	rtnl_unlock();
2437 	return err;
2438 }
2439 
2440 int addrconf_del_ifaddr(struct net *net, void __user *arg)
2441 {
2442 	struct in6_ifreq ireq;
2443 	int err;
2444 
2445 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2446 		return -EPERM;
2447 
2448 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2449 		return -EFAULT;
2450 
2451 	rtnl_lock();
2452 	err = inet6_addr_del(net, ireq.ifr6_ifindex, &ireq.ifr6_addr,
2453 			     ireq.ifr6_prefixlen);
2454 	rtnl_unlock();
2455 	return err;
2456 }
2457 
2458 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
2459 		     int plen, int scope)
2460 {
2461 	struct inet6_ifaddr *ifp;
2462 
2463 	ifp = ipv6_add_addr(idev, addr, plen, scope, IFA_F_PERMANENT);
2464 	if (!IS_ERR(ifp)) {
2465 		spin_lock_bh(&ifp->lock);
2466 		ifp->flags &= ~IFA_F_TENTATIVE;
2467 		spin_unlock_bh(&ifp->lock);
2468 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
2469 		in6_ifa_put(ifp);
2470 	}
2471 }
2472 
2473 #if IS_ENABLED(CONFIG_IPV6_SIT)
2474 static void sit_add_v4_addrs(struct inet6_dev *idev)
2475 {
2476 	struct in6_addr addr;
2477 	struct net_device *dev;
2478 	struct net *net = dev_net(idev->dev);
2479 	int scope;
2480 
2481 	ASSERT_RTNL();
2482 
2483 	memset(&addr, 0, sizeof(struct in6_addr));
2484 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
2485 
2486 	if (idev->dev->flags&IFF_POINTOPOINT) {
2487 		addr.s6_addr32[0] = htonl(0xfe800000);
2488 		scope = IFA_LINK;
2489 	} else {
2490 		scope = IPV6_ADDR_COMPATv4;
2491 	}
2492 
2493 	if (addr.s6_addr32[3]) {
2494 		add_addr(idev, &addr, 128, scope);
2495 		return;
2496 	}
2497 
2498 	for_each_netdev(net, dev) {
2499 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
2500 		if (in_dev && (dev->flags & IFF_UP)) {
2501 			struct in_ifaddr *ifa;
2502 
2503 			int flag = scope;
2504 
2505 			for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
2506 				int plen;
2507 
2508 				addr.s6_addr32[3] = ifa->ifa_local;
2509 
2510 				if (ifa->ifa_scope == RT_SCOPE_LINK)
2511 					continue;
2512 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
2513 					if (idev->dev->flags&IFF_POINTOPOINT)
2514 						continue;
2515 					flag |= IFA_HOST;
2516 				}
2517 				if (idev->dev->flags&IFF_POINTOPOINT)
2518 					plen = 64;
2519 				else
2520 					plen = 96;
2521 
2522 				add_addr(idev, &addr, plen, flag);
2523 			}
2524 		}
2525 	}
2526 }
2527 #endif
2528 
2529 static void init_loopback(struct net_device *dev)
2530 {
2531 	struct inet6_dev  *idev;
2532 
2533 	/* ::1 */
2534 
2535 	ASSERT_RTNL();
2536 
2537 	if ((idev = ipv6_find_idev(dev)) == NULL) {
2538 		pr_debug("%s: add_dev failed\n", __func__);
2539 		return;
2540 	}
2541 
2542 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST);
2543 }
2544 
2545 static void addrconf_add_linklocal(struct inet6_dev *idev, const struct in6_addr *addr)
2546 {
2547 	struct inet6_ifaddr *ifp;
2548 	u32 addr_flags = IFA_F_PERMANENT;
2549 
2550 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2551 	if (idev->cnf.optimistic_dad &&
2552 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
2553 		addr_flags |= IFA_F_OPTIMISTIC;
2554 #endif
2555 
2556 
2557 	ifp = ipv6_add_addr(idev, addr, 64, IFA_LINK, addr_flags);
2558 	if (!IS_ERR(ifp)) {
2559 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, idev->dev, 0, 0);
2560 		addrconf_dad_start(ifp);
2561 		in6_ifa_put(ifp);
2562 	}
2563 }
2564 
2565 static void addrconf_dev_config(struct net_device *dev)
2566 {
2567 	struct in6_addr addr;
2568 	struct inet6_dev *idev;
2569 
2570 	ASSERT_RTNL();
2571 
2572 	if ((dev->type != ARPHRD_ETHER) &&
2573 	    (dev->type != ARPHRD_FDDI) &&
2574 	    (dev->type != ARPHRD_ARCNET) &&
2575 	    (dev->type != ARPHRD_INFINIBAND) &&
2576 	    (dev->type != ARPHRD_IEEE802154)) {
2577 		/* Alas, we support only Ethernet autoconfiguration. */
2578 		return;
2579 	}
2580 
2581 	idev = addrconf_add_dev(dev);
2582 	if (IS_ERR(idev))
2583 		return;
2584 
2585 	memset(&addr, 0, sizeof(struct in6_addr));
2586 	addr.s6_addr32[0] = htonl(0xFE800000);
2587 
2588 	if (ipv6_generate_eui64(addr.s6_addr + 8, dev) == 0)
2589 		addrconf_add_linklocal(idev, &addr);
2590 }
2591 
2592 #if IS_ENABLED(CONFIG_IPV6_SIT)
2593 static void addrconf_sit_config(struct net_device *dev)
2594 {
2595 	struct inet6_dev *idev;
2596 
2597 	ASSERT_RTNL();
2598 
2599 	/*
2600 	 * Configure the tunnel with one of our IPv4
2601 	 * addresses... we should configure all of
2602 	 * our v4 addrs in the tunnel
2603 	 */
2604 
2605 	if ((idev = ipv6_find_idev(dev)) == NULL) {
2606 		pr_debug("%s: add_dev failed\n", __func__);
2607 		return;
2608 	}
2609 
2610 	if (dev->priv_flags & IFF_ISATAP) {
2611 		struct in6_addr addr;
2612 
2613 		ipv6_addr_set(&addr,  htonl(0xFE800000), 0, 0, 0);
2614 		addrconf_prefix_route(&addr, 64, dev, 0, 0);
2615 		if (!ipv6_generate_eui64(addr.s6_addr + 8, dev))
2616 			addrconf_add_linklocal(idev, &addr);
2617 		return;
2618 	}
2619 
2620 	sit_add_v4_addrs(idev);
2621 
2622 	if (dev->flags&IFF_POINTOPOINT)
2623 		addrconf_add_mroute(dev);
2624 	else
2625 		sit_route_add(dev);
2626 }
2627 #endif
2628 
2629 #if IS_ENABLED(CONFIG_NET_IPGRE)
2630 static void addrconf_gre_config(struct net_device *dev)
2631 {
2632 	struct inet6_dev *idev;
2633 	struct in6_addr addr;
2634 
2635 	pr_info("%s(%s)\n", __func__, dev->name);
2636 
2637 	ASSERT_RTNL();
2638 
2639 	if ((idev = ipv6_find_idev(dev)) == NULL) {
2640 		pr_debug("%s: add_dev failed\n", __func__);
2641 		return;
2642 	}
2643 
2644 	ipv6_addr_set(&addr,  htonl(0xFE800000), 0, 0, 0);
2645 	addrconf_prefix_route(&addr, 64, dev, 0, 0);
2646 
2647 	if (!ipv6_generate_eui64(addr.s6_addr + 8, dev))
2648 		addrconf_add_linklocal(idev, &addr);
2649 }
2650 #endif
2651 
2652 static inline int
2653 ipv6_inherit_linklocal(struct inet6_dev *idev, struct net_device *link_dev)
2654 {
2655 	struct in6_addr lladdr;
2656 
2657 	if (!ipv6_get_lladdr(link_dev, &lladdr, IFA_F_TENTATIVE)) {
2658 		addrconf_add_linklocal(idev, &lladdr);
2659 		return 0;
2660 	}
2661 	return -1;
2662 }
2663 
2664 static void ip6_tnl_add_linklocal(struct inet6_dev *idev)
2665 {
2666 	struct net_device *link_dev;
2667 	struct net *net = dev_net(idev->dev);
2668 
2669 	/* first try to inherit the link-local address from the link device */
2670 	if (idev->dev->iflink &&
2671 	    (link_dev = __dev_get_by_index(net, idev->dev->iflink))) {
2672 		if (!ipv6_inherit_linklocal(idev, link_dev))
2673 			return;
2674 	}
2675 	/* then try to inherit it from any device */
2676 	for_each_netdev(net, link_dev) {
2677 		if (!ipv6_inherit_linklocal(idev, link_dev))
2678 			return;
2679 	}
2680 	pr_debug("init ip6-ip6: add_linklocal failed\n");
2681 }
2682 
2683 /*
2684  * Autoconfigure tunnel with a link-local address so routing protocols,
2685  * DHCPv6, MLD etc. can be run over the virtual link
2686  */
2687 
2688 static void addrconf_ip6_tnl_config(struct net_device *dev)
2689 {
2690 	struct inet6_dev *idev;
2691 
2692 	ASSERT_RTNL();
2693 
2694 	idev = addrconf_add_dev(dev);
2695 	if (IS_ERR(idev)) {
2696 		pr_debug("init ip6-ip6: add_dev failed\n");
2697 		return;
2698 	}
2699 	ip6_tnl_add_linklocal(idev);
2700 }
2701 
2702 static int addrconf_notify(struct notifier_block *this, unsigned long event,
2703 			   void *data)
2704 {
2705 	struct net_device *dev = (struct net_device *) data;
2706 	struct inet6_dev *idev = __in6_dev_get(dev);
2707 	int run_pending = 0;
2708 	int err;
2709 
2710 	switch (event) {
2711 	case NETDEV_REGISTER:
2712 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
2713 			idev = ipv6_add_dev(dev);
2714 			if (!idev)
2715 				return notifier_from_errno(-ENOMEM);
2716 		}
2717 		break;
2718 
2719 	case NETDEV_UP:
2720 	case NETDEV_CHANGE:
2721 		if (dev->flags & IFF_SLAVE)
2722 			break;
2723 
2724 		if (event == NETDEV_UP) {
2725 			if (!addrconf_qdisc_ok(dev)) {
2726 				/* device is not ready yet. */
2727 				pr_info("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
2728 					dev->name);
2729 				break;
2730 			}
2731 
2732 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
2733 				idev = ipv6_add_dev(dev);
2734 
2735 			if (idev) {
2736 				idev->if_flags |= IF_READY;
2737 				run_pending = 1;
2738 			}
2739 		} else {
2740 			if (!addrconf_qdisc_ok(dev)) {
2741 				/* device is still not ready. */
2742 				break;
2743 			}
2744 
2745 			if (idev) {
2746 				if (idev->if_flags & IF_READY)
2747 					/* device is already configured. */
2748 					break;
2749 				idev->if_flags |= IF_READY;
2750 			}
2751 
2752 			pr_info("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
2753 				dev->name);
2754 
2755 			run_pending = 1;
2756 		}
2757 
2758 		switch (dev->type) {
2759 #if IS_ENABLED(CONFIG_IPV6_SIT)
2760 		case ARPHRD_SIT:
2761 			addrconf_sit_config(dev);
2762 			break;
2763 #endif
2764 #if IS_ENABLED(CONFIG_NET_IPGRE)
2765 		case ARPHRD_IPGRE:
2766 			addrconf_gre_config(dev);
2767 			break;
2768 #endif
2769 		case ARPHRD_TUNNEL6:
2770 			addrconf_ip6_tnl_config(dev);
2771 			break;
2772 		case ARPHRD_LOOPBACK:
2773 			init_loopback(dev);
2774 			break;
2775 
2776 		default:
2777 			addrconf_dev_config(dev);
2778 			break;
2779 		}
2780 
2781 		if (idev) {
2782 			if (run_pending)
2783 				addrconf_dad_run(idev);
2784 
2785 			/*
2786 			 * If the MTU changed during the interface down,
2787 			 * when the interface up, the changed MTU must be
2788 			 * reflected in the idev as well as routers.
2789 			 */
2790 			if (idev->cnf.mtu6 != dev->mtu &&
2791 			    dev->mtu >= IPV6_MIN_MTU) {
2792 				rt6_mtu_change(dev, dev->mtu);
2793 				idev->cnf.mtu6 = dev->mtu;
2794 			}
2795 			idev->tstamp = jiffies;
2796 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
2797 
2798 			/*
2799 			 * If the changed mtu during down is lower than
2800 			 * IPV6_MIN_MTU stop IPv6 on this interface.
2801 			 */
2802 			if (dev->mtu < IPV6_MIN_MTU)
2803 				addrconf_ifdown(dev, 1);
2804 		}
2805 		break;
2806 
2807 	case NETDEV_CHANGEMTU:
2808 		if (idev && dev->mtu >= IPV6_MIN_MTU) {
2809 			rt6_mtu_change(dev, dev->mtu);
2810 			idev->cnf.mtu6 = dev->mtu;
2811 			break;
2812 		}
2813 
2814 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
2815 			idev = ipv6_add_dev(dev);
2816 			if (idev)
2817 				break;
2818 		}
2819 
2820 		/*
2821 		 * MTU falled under IPV6_MIN_MTU.
2822 		 * Stop IPv6 on this interface.
2823 		 */
2824 
2825 	case NETDEV_DOWN:
2826 	case NETDEV_UNREGISTER:
2827 		/*
2828 		 *	Remove all addresses from this interface.
2829 		 */
2830 		addrconf_ifdown(dev, event != NETDEV_DOWN);
2831 		break;
2832 
2833 	case NETDEV_CHANGENAME:
2834 		if (idev) {
2835 			snmp6_unregister_dev(idev);
2836 			addrconf_sysctl_unregister(idev);
2837 			addrconf_sysctl_register(idev);
2838 			err = snmp6_register_dev(idev);
2839 			if (err)
2840 				return notifier_from_errno(err);
2841 		}
2842 		break;
2843 
2844 	case NETDEV_PRE_TYPE_CHANGE:
2845 	case NETDEV_POST_TYPE_CHANGE:
2846 		addrconf_type_change(dev, event);
2847 		break;
2848 	}
2849 
2850 	return NOTIFY_OK;
2851 }
2852 
2853 /*
2854  *	addrconf module should be notified of a device going up
2855  */
2856 static struct notifier_block ipv6_dev_notf = {
2857 	.notifier_call = addrconf_notify,
2858 };
2859 
2860 static void addrconf_type_change(struct net_device *dev, unsigned long event)
2861 {
2862 	struct inet6_dev *idev;
2863 	ASSERT_RTNL();
2864 
2865 	idev = __in6_dev_get(dev);
2866 
2867 	if (event == NETDEV_POST_TYPE_CHANGE)
2868 		ipv6_mc_remap(idev);
2869 	else if (event == NETDEV_PRE_TYPE_CHANGE)
2870 		ipv6_mc_unmap(idev);
2871 }
2872 
2873 static int addrconf_ifdown(struct net_device *dev, int how)
2874 {
2875 	struct net *net = dev_net(dev);
2876 	struct inet6_dev *idev;
2877 	struct inet6_ifaddr *ifa;
2878 	int state, i;
2879 
2880 	ASSERT_RTNL();
2881 
2882 	rt6_ifdown(net, dev);
2883 	neigh_ifdown(&nd_tbl, dev);
2884 
2885 	idev = __in6_dev_get(dev);
2886 	if (idev == NULL)
2887 		return -ENODEV;
2888 
2889 	/*
2890 	 * Step 1: remove reference to ipv6 device from parent device.
2891 	 *	   Do not dev_put!
2892 	 */
2893 	if (how) {
2894 		idev->dead = 1;
2895 
2896 		/* protected by rtnl_lock */
2897 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
2898 
2899 		/* Step 1.5: remove snmp6 entry */
2900 		snmp6_unregister_dev(idev);
2901 
2902 	}
2903 
2904 	/* Step 2: clear hash table */
2905 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
2906 		struct hlist_head *h = &inet6_addr_lst[i];
2907 
2908 		spin_lock_bh(&addrconf_hash_lock);
2909 	restart:
2910 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
2911 			if (ifa->idev == idev) {
2912 				hlist_del_init_rcu(&ifa->addr_lst);
2913 				addrconf_del_timer(ifa);
2914 				goto restart;
2915 			}
2916 		}
2917 		spin_unlock_bh(&addrconf_hash_lock);
2918 	}
2919 
2920 	write_lock_bh(&idev->lock);
2921 
2922 	/* Step 2: clear flags for stateless addrconf */
2923 	if (!how)
2924 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
2925 
2926 #ifdef CONFIG_IPV6_PRIVACY
2927 	if (how && del_timer(&idev->regen_timer))
2928 		in6_dev_put(idev);
2929 
2930 	/* Step 3: clear tempaddr list */
2931 	while (!list_empty(&idev->tempaddr_list)) {
2932 		ifa = list_first_entry(&idev->tempaddr_list,
2933 				       struct inet6_ifaddr, tmp_list);
2934 		list_del(&ifa->tmp_list);
2935 		write_unlock_bh(&idev->lock);
2936 		spin_lock_bh(&ifa->lock);
2937 
2938 		if (ifa->ifpub) {
2939 			in6_ifa_put(ifa->ifpub);
2940 			ifa->ifpub = NULL;
2941 		}
2942 		spin_unlock_bh(&ifa->lock);
2943 		in6_ifa_put(ifa);
2944 		write_lock_bh(&idev->lock);
2945 	}
2946 #endif
2947 
2948 	while (!list_empty(&idev->addr_list)) {
2949 		ifa = list_first_entry(&idev->addr_list,
2950 				       struct inet6_ifaddr, if_list);
2951 		addrconf_del_timer(ifa);
2952 
2953 		list_del(&ifa->if_list);
2954 
2955 		write_unlock_bh(&idev->lock);
2956 
2957 		spin_lock_bh(&ifa->state_lock);
2958 		state = ifa->state;
2959 		ifa->state = INET6_IFADDR_STATE_DEAD;
2960 		spin_unlock_bh(&ifa->state_lock);
2961 
2962 		if (state != INET6_IFADDR_STATE_DEAD) {
2963 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
2964 			atomic_notifier_call_chain(&inet6addr_chain, NETDEV_DOWN, ifa);
2965 		}
2966 		in6_ifa_put(ifa);
2967 
2968 		write_lock_bh(&idev->lock);
2969 	}
2970 
2971 	write_unlock_bh(&idev->lock);
2972 
2973 	/* Step 5: Discard multicast list */
2974 	if (how)
2975 		ipv6_mc_destroy_dev(idev);
2976 	else
2977 		ipv6_mc_down(idev);
2978 
2979 	idev->tstamp = jiffies;
2980 
2981 	/* Last: Shot the device (if unregistered) */
2982 	if (how) {
2983 		addrconf_sysctl_unregister(idev);
2984 		neigh_parms_release(&nd_tbl, idev->nd_parms);
2985 		neigh_ifdown(&nd_tbl, dev);
2986 		in6_dev_put(idev);
2987 	}
2988 	return 0;
2989 }
2990 
2991 static void addrconf_rs_timer(unsigned long data)
2992 {
2993 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *) data;
2994 	struct inet6_dev *idev = ifp->idev;
2995 
2996 	read_lock(&idev->lock);
2997 	if (idev->dead || !(idev->if_flags & IF_READY))
2998 		goto out;
2999 
3000 	if (!ipv6_accept_ra(idev))
3001 		goto out;
3002 
3003 	/* Announcement received after solicitation was sent */
3004 	if (idev->if_flags & IF_RA_RCVD)
3005 		goto out;
3006 
3007 	spin_lock(&ifp->lock);
3008 	if (ifp->probes++ < idev->cnf.rtr_solicits) {
3009 		/* The wait after the last probe can be shorter */
3010 		addrconf_mod_timer(ifp, AC_RS,
3011 				   (ifp->probes == idev->cnf.rtr_solicits) ?
3012 				   idev->cnf.rtr_solicit_delay :
3013 				   idev->cnf.rtr_solicit_interval);
3014 		spin_unlock(&ifp->lock);
3015 
3016 		ndisc_send_rs(idev->dev, &ifp->addr, &in6addr_linklocal_allrouters);
3017 	} else {
3018 		spin_unlock(&ifp->lock);
3019 		/*
3020 		 * Note: we do not support deprecated "all on-link"
3021 		 * assumption any longer.
3022 		 */
3023 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
3024 	}
3025 
3026 out:
3027 	read_unlock(&idev->lock);
3028 	in6_ifa_put(ifp);
3029 }
3030 
3031 /*
3032  *	Duplicate Address Detection
3033  */
3034 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
3035 {
3036 	unsigned long rand_num;
3037 	struct inet6_dev *idev = ifp->idev;
3038 
3039 	if (ifp->flags & IFA_F_OPTIMISTIC)
3040 		rand_num = 0;
3041 	else
3042 		rand_num = net_random() % (idev->cnf.rtr_solicit_delay ? : 1);
3043 
3044 	ifp->probes = idev->cnf.dad_transmits;
3045 	addrconf_mod_timer(ifp, AC_DAD, rand_num);
3046 }
3047 
3048 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
3049 {
3050 	struct inet6_dev *idev = ifp->idev;
3051 	struct net_device *dev = idev->dev;
3052 
3053 	addrconf_join_solict(dev, &ifp->addr);
3054 
3055 	net_srandom(ifp->addr.s6_addr32[3]);
3056 
3057 	read_lock_bh(&idev->lock);
3058 	spin_lock(&ifp->lock);
3059 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
3060 		goto out;
3061 
3062 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
3063 	    idev->cnf.accept_dad < 1 ||
3064 	    !(ifp->flags&IFA_F_TENTATIVE) ||
3065 	    ifp->flags & IFA_F_NODAD) {
3066 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3067 		spin_unlock(&ifp->lock);
3068 		read_unlock_bh(&idev->lock);
3069 
3070 		addrconf_dad_completed(ifp);
3071 		return;
3072 	}
3073 
3074 	if (!(idev->if_flags & IF_READY)) {
3075 		spin_unlock(&ifp->lock);
3076 		read_unlock_bh(&idev->lock);
3077 		/*
3078 		 * If the device is not ready:
3079 		 * - keep it tentative if it is a permanent address.
3080 		 * - otherwise, kill it.
3081 		 */
3082 		in6_ifa_hold(ifp);
3083 		addrconf_dad_stop(ifp, 0);
3084 		return;
3085 	}
3086 
3087 	/*
3088 	 * Optimistic nodes can start receiving
3089 	 * Frames right away
3090 	 */
3091 	if (ifp->flags & IFA_F_OPTIMISTIC)
3092 		ip6_ins_rt(ifp->rt);
3093 
3094 	addrconf_dad_kick(ifp);
3095 out:
3096 	spin_unlock(&ifp->lock);
3097 	read_unlock_bh(&idev->lock);
3098 }
3099 
3100 static void addrconf_dad_timer(unsigned long data)
3101 {
3102 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *) data;
3103 	struct inet6_dev *idev = ifp->idev;
3104 	struct in6_addr mcaddr;
3105 
3106 	if (!ifp->probes && addrconf_dad_end(ifp))
3107 		goto out;
3108 
3109 	read_lock(&idev->lock);
3110 	if (idev->dead || !(idev->if_flags & IF_READY)) {
3111 		read_unlock(&idev->lock);
3112 		goto out;
3113 	}
3114 
3115 	spin_lock(&ifp->lock);
3116 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
3117 		spin_unlock(&ifp->lock);
3118 		read_unlock(&idev->lock);
3119 		goto out;
3120 	}
3121 
3122 	if (ifp->probes == 0) {
3123 		/*
3124 		 * DAD was successful
3125 		 */
3126 
3127 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3128 		spin_unlock(&ifp->lock);
3129 		read_unlock(&idev->lock);
3130 
3131 		addrconf_dad_completed(ifp);
3132 
3133 		goto out;
3134 	}
3135 
3136 	ifp->probes--;
3137 	addrconf_mod_timer(ifp, AC_DAD, ifp->idev->nd_parms->retrans_time);
3138 	spin_unlock(&ifp->lock);
3139 	read_unlock(&idev->lock);
3140 
3141 	/* send a neighbour solicitation for our addr */
3142 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
3143 	ndisc_send_ns(ifp->idev->dev, NULL, &ifp->addr, &mcaddr, &in6addr_any);
3144 out:
3145 	in6_ifa_put(ifp);
3146 }
3147 
3148 static void addrconf_dad_completed(struct inet6_ifaddr *ifp)
3149 {
3150 	struct net_device *dev = ifp->idev->dev;
3151 
3152 	/*
3153 	 *	Configure the address for reception. Now it is valid.
3154 	 */
3155 
3156 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
3157 
3158 	/* If added prefix is link local and we are prepared to process
3159 	   router advertisements, start sending router solicitations.
3160 	 */
3161 
3162 	if (ipv6_accept_ra(ifp->idev) &&
3163 	    ifp->idev->cnf.rtr_solicits > 0 &&
3164 	    (dev->flags&IFF_LOOPBACK) == 0 &&
3165 	    (ipv6_addr_type(&ifp->addr) & IPV6_ADDR_LINKLOCAL)) {
3166 		/*
3167 		 *	If a host as already performed a random delay
3168 		 *	[...] as part of DAD [...] there is no need
3169 		 *	to delay again before sending the first RS
3170 		 */
3171 		ndisc_send_rs(ifp->idev->dev, &ifp->addr, &in6addr_linklocal_allrouters);
3172 
3173 		spin_lock_bh(&ifp->lock);
3174 		ifp->probes = 1;
3175 		ifp->idev->if_flags |= IF_RS_SENT;
3176 		addrconf_mod_timer(ifp, AC_RS, ifp->idev->cnf.rtr_solicit_interval);
3177 		spin_unlock_bh(&ifp->lock);
3178 	}
3179 }
3180 
3181 static void addrconf_dad_run(struct inet6_dev *idev)
3182 {
3183 	struct inet6_ifaddr *ifp;
3184 
3185 	read_lock_bh(&idev->lock);
3186 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
3187 		spin_lock(&ifp->lock);
3188 		if (ifp->flags & IFA_F_TENTATIVE &&
3189 		    ifp->state == INET6_IFADDR_STATE_DAD)
3190 			addrconf_dad_kick(ifp);
3191 		spin_unlock(&ifp->lock);
3192 	}
3193 	read_unlock_bh(&idev->lock);
3194 }
3195 
3196 #ifdef CONFIG_PROC_FS
3197 struct if6_iter_state {
3198 	struct seq_net_private p;
3199 	int bucket;
3200 	int offset;
3201 };
3202 
3203 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
3204 {
3205 	struct inet6_ifaddr *ifa = NULL;
3206 	struct if6_iter_state *state = seq->private;
3207 	struct net *net = seq_file_net(seq);
3208 	int p = 0;
3209 
3210 	/* initial bucket if pos is 0 */
3211 	if (pos == 0) {
3212 		state->bucket = 0;
3213 		state->offset = 0;
3214 	}
3215 
3216 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
3217 		hlist_for_each_entry_rcu_bh(ifa, &inet6_addr_lst[state->bucket],
3218 					 addr_lst) {
3219 			if (!net_eq(dev_net(ifa->idev->dev), net))
3220 				continue;
3221 			/* sync with offset */
3222 			if (p < state->offset) {
3223 				p++;
3224 				continue;
3225 			}
3226 			state->offset++;
3227 			return ifa;
3228 		}
3229 
3230 		/* prepare for next bucket */
3231 		state->offset = 0;
3232 		p = 0;
3233 	}
3234 	return NULL;
3235 }
3236 
3237 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
3238 					 struct inet6_ifaddr *ifa)
3239 {
3240 	struct if6_iter_state *state = seq->private;
3241 	struct net *net = seq_file_net(seq);
3242 
3243 	hlist_for_each_entry_continue_rcu_bh(ifa, addr_lst) {
3244 		if (!net_eq(dev_net(ifa->idev->dev), net))
3245 			continue;
3246 		state->offset++;
3247 		return ifa;
3248 	}
3249 
3250 	while (++state->bucket < IN6_ADDR_HSIZE) {
3251 		state->offset = 0;
3252 		hlist_for_each_entry_rcu_bh(ifa,
3253 				     &inet6_addr_lst[state->bucket], addr_lst) {
3254 			if (!net_eq(dev_net(ifa->idev->dev), net))
3255 				continue;
3256 			state->offset++;
3257 			return ifa;
3258 		}
3259 	}
3260 
3261 	return NULL;
3262 }
3263 
3264 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
3265 	__acquires(rcu_bh)
3266 {
3267 	rcu_read_lock_bh();
3268 	return if6_get_first(seq, *pos);
3269 }
3270 
3271 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3272 {
3273 	struct inet6_ifaddr *ifa;
3274 
3275 	ifa = if6_get_next(seq, v);
3276 	++*pos;
3277 	return ifa;
3278 }
3279 
3280 static void if6_seq_stop(struct seq_file *seq, void *v)
3281 	__releases(rcu_bh)
3282 {
3283 	rcu_read_unlock_bh();
3284 }
3285 
3286 static int if6_seq_show(struct seq_file *seq, void *v)
3287 {
3288 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
3289 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
3290 		   &ifp->addr,
3291 		   ifp->idev->dev->ifindex,
3292 		   ifp->prefix_len,
3293 		   ifp->scope,
3294 		   ifp->flags,
3295 		   ifp->idev->dev->name);
3296 	return 0;
3297 }
3298 
3299 static const struct seq_operations if6_seq_ops = {
3300 	.start	= if6_seq_start,
3301 	.next	= if6_seq_next,
3302 	.show	= if6_seq_show,
3303 	.stop	= if6_seq_stop,
3304 };
3305 
3306 static int if6_seq_open(struct inode *inode, struct file *file)
3307 {
3308 	return seq_open_net(inode, file, &if6_seq_ops,
3309 			    sizeof(struct if6_iter_state));
3310 }
3311 
3312 static const struct file_operations if6_fops = {
3313 	.owner		= THIS_MODULE,
3314 	.open		= if6_seq_open,
3315 	.read		= seq_read,
3316 	.llseek		= seq_lseek,
3317 	.release	= seq_release_net,
3318 };
3319 
3320 static int __net_init if6_proc_net_init(struct net *net)
3321 {
3322 	if (!proc_create("if_inet6", S_IRUGO, net->proc_net, &if6_fops))
3323 		return -ENOMEM;
3324 	return 0;
3325 }
3326 
3327 static void __net_exit if6_proc_net_exit(struct net *net)
3328 {
3329 	remove_proc_entry("if_inet6", net->proc_net);
3330 }
3331 
3332 static struct pernet_operations if6_proc_net_ops = {
3333        .init = if6_proc_net_init,
3334        .exit = if6_proc_net_exit,
3335 };
3336 
3337 int __init if6_proc_init(void)
3338 {
3339 	return register_pernet_subsys(&if6_proc_net_ops);
3340 }
3341 
3342 void if6_proc_exit(void)
3343 {
3344 	unregister_pernet_subsys(&if6_proc_net_ops);
3345 }
3346 #endif	/* CONFIG_PROC_FS */
3347 
3348 #if IS_ENABLED(CONFIG_IPV6_MIP6)
3349 /* Check if address is a home address configured on any interface. */
3350 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
3351 {
3352 	int ret = 0;
3353 	struct inet6_ifaddr *ifp = NULL;
3354 	unsigned int hash = inet6_addr_hash(addr);
3355 
3356 	rcu_read_lock_bh();
3357 	hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[hash], addr_lst) {
3358 		if (!net_eq(dev_net(ifp->idev->dev), net))
3359 			continue;
3360 		if (ipv6_addr_equal(&ifp->addr, addr) &&
3361 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
3362 			ret = 1;
3363 			break;
3364 		}
3365 	}
3366 	rcu_read_unlock_bh();
3367 	return ret;
3368 }
3369 #endif
3370 
3371 /*
3372  *	Periodic address status verification
3373  */
3374 
3375 static void addrconf_verify(unsigned long foo)
3376 {
3377 	unsigned long now, next, next_sec, next_sched;
3378 	struct inet6_ifaddr *ifp;
3379 	int i;
3380 
3381 	rcu_read_lock_bh();
3382 	spin_lock(&addrconf_verify_lock);
3383 	now = jiffies;
3384 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
3385 
3386 	del_timer(&addr_chk_timer);
3387 
3388 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3389 restart:
3390 		hlist_for_each_entry_rcu_bh(ifp,
3391 					 &inet6_addr_lst[i], addr_lst) {
3392 			unsigned long age;
3393 
3394 			if (ifp->flags & IFA_F_PERMANENT)
3395 				continue;
3396 
3397 			spin_lock(&ifp->lock);
3398 			/* We try to batch several events at once. */
3399 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
3400 
3401 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
3402 			    age >= ifp->valid_lft) {
3403 				spin_unlock(&ifp->lock);
3404 				in6_ifa_hold(ifp);
3405 				ipv6_del_addr(ifp);
3406 				goto restart;
3407 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
3408 				spin_unlock(&ifp->lock);
3409 				continue;
3410 			} else if (age >= ifp->prefered_lft) {
3411 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
3412 				int deprecate = 0;
3413 
3414 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
3415 					deprecate = 1;
3416 					ifp->flags |= IFA_F_DEPRECATED;
3417 				}
3418 
3419 				if (time_before(ifp->tstamp + ifp->valid_lft * HZ, next))
3420 					next = ifp->tstamp + ifp->valid_lft * HZ;
3421 
3422 				spin_unlock(&ifp->lock);
3423 
3424 				if (deprecate) {
3425 					in6_ifa_hold(ifp);
3426 
3427 					ipv6_ifa_notify(0, ifp);
3428 					in6_ifa_put(ifp);
3429 					goto restart;
3430 				}
3431 #ifdef CONFIG_IPV6_PRIVACY
3432 			} else if ((ifp->flags&IFA_F_TEMPORARY) &&
3433 				   !(ifp->flags&IFA_F_TENTATIVE)) {
3434 				unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
3435 					ifp->idev->cnf.dad_transmits *
3436 					ifp->idev->nd_parms->retrans_time / HZ;
3437 
3438 				if (age >= ifp->prefered_lft - regen_advance) {
3439 					struct inet6_ifaddr *ifpub = ifp->ifpub;
3440 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
3441 						next = ifp->tstamp + ifp->prefered_lft * HZ;
3442 					if (!ifp->regen_count && ifpub) {
3443 						ifp->regen_count++;
3444 						in6_ifa_hold(ifp);
3445 						in6_ifa_hold(ifpub);
3446 						spin_unlock(&ifp->lock);
3447 
3448 						spin_lock(&ifpub->lock);
3449 						ifpub->regen_count = 0;
3450 						spin_unlock(&ifpub->lock);
3451 						ipv6_create_tempaddr(ifpub, ifp);
3452 						in6_ifa_put(ifpub);
3453 						in6_ifa_put(ifp);
3454 						goto restart;
3455 					}
3456 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
3457 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
3458 				spin_unlock(&ifp->lock);
3459 #endif
3460 			} else {
3461 				/* ifp->prefered_lft <= ifp->valid_lft */
3462 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
3463 					next = ifp->tstamp + ifp->prefered_lft * HZ;
3464 				spin_unlock(&ifp->lock);
3465 			}
3466 		}
3467 	}
3468 
3469 	next_sec = round_jiffies_up(next);
3470 	next_sched = next;
3471 
3472 	/* If rounded timeout is accurate enough, accept it. */
3473 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
3474 		next_sched = next_sec;
3475 
3476 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
3477 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
3478 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
3479 
3480 	ADBG((KERN_DEBUG "now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
3481 	      now, next, next_sec, next_sched));
3482 
3483 	addr_chk_timer.expires = next_sched;
3484 	add_timer(&addr_chk_timer);
3485 	spin_unlock(&addrconf_verify_lock);
3486 	rcu_read_unlock_bh();
3487 }
3488 
3489 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local)
3490 {
3491 	struct in6_addr *pfx = NULL;
3492 
3493 	if (addr)
3494 		pfx = nla_data(addr);
3495 
3496 	if (local) {
3497 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
3498 			pfx = NULL;
3499 		else
3500 			pfx = nla_data(local);
3501 	}
3502 
3503 	return pfx;
3504 }
3505 
3506 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
3507 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
3508 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
3509 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
3510 };
3511 
3512 static int
3513 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
3514 {
3515 	struct net *net = sock_net(skb->sk);
3516 	struct ifaddrmsg *ifm;
3517 	struct nlattr *tb[IFA_MAX+1];
3518 	struct in6_addr *pfx;
3519 	int err;
3520 
3521 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
3522 	if (err < 0)
3523 		return err;
3524 
3525 	ifm = nlmsg_data(nlh);
3526 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL]);
3527 	if (pfx == NULL)
3528 		return -EINVAL;
3529 
3530 	return inet6_addr_del(net, ifm->ifa_index, pfx, ifm->ifa_prefixlen);
3531 }
3532 
3533 static int inet6_addr_modify(struct inet6_ifaddr *ifp, u8 ifa_flags,
3534 			     u32 prefered_lft, u32 valid_lft)
3535 {
3536 	u32 flags;
3537 	clock_t expires;
3538 	unsigned long timeout;
3539 
3540 	if (!valid_lft || (prefered_lft > valid_lft))
3541 		return -EINVAL;
3542 
3543 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
3544 	if (addrconf_finite_timeout(timeout)) {
3545 		expires = jiffies_to_clock_t(timeout * HZ);
3546 		valid_lft = timeout;
3547 		flags = RTF_EXPIRES;
3548 	} else {
3549 		expires = 0;
3550 		flags = 0;
3551 		ifa_flags |= IFA_F_PERMANENT;
3552 	}
3553 
3554 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
3555 	if (addrconf_finite_timeout(timeout)) {
3556 		if (timeout == 0)
3557 			ifa_flags |= IFA_F_DEPRECATED;
3558 		prefered_lft = timeout;
3559 	}
3560 
3561 	spin_lock_bh(&ifp->lock);
3562 	ifp->flags = (ifp->flags & ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD | IFA_F_HOMEADDRESS)) | ifa_flags;
3563 	ifp->tstamp = jiffies;
3564 	ifp->valid_lft = valid_lft;
3565 	ifp->prefered_lft = prefered_lft;
3566 
3567 	spin_unlock_bh(&ifp->lock);
3568 	if (!(ifp->flags&IFA_F_TENTATIVE))
3569 		ipv6_ifa_notify(0, ifp);
3570 
3571 	addrconf_prefix_route(&ifp->addr, ifp->prefix_len, ifp->idev->dev,
3572 			      expires, flags);
3573 	addrconf_verify(0);
3574 
3575 	return 0;
3576 }
3577 
3578 static int
3579 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
3580 {
3581 	struct net *net = sock_net(skb->sk);
3582 	struct ifaddrmsg *ifm;
3583 	struct nlattr *tb[IFA_MAX+1];
3584 	struct in6_addr *pfx;
3585 	struct inet6_ifaddr *ifa;
3586 	struct net_device *dev;
3587 	u32 valid_lft = INFINITY_LIFE_TIME, preferred_lft = INFINITY_LIFE_TIME;
3588 	u8 ifa_flags;
3589 	int err;
3590 
3591 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
3592 	if (err < 0)
3593 		return err;
3594 
3595 	ifm = nlmsg_data(nlh);
3596 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL]);
3597 	if (pfx == NULL)
3598 		return -EINVAL;
3599 
3600 	if (tb[IFA_CACHEINFO]) {
3601 		struct ifa_cacheinfo *ci;
3602 
3603 		ci = nla_data(tb[IFA_CACHEINFO]);
3604 		valid_lft = ci->ifa_valid;
3605 		preferred_lft = ci->ifa_prefered;
3606 	} else {
3607 		preferred_lft = INFINITY_LIFE_TIME;
3608 		valid_lft = INFINITY_LIFE_TIME;
3609 	}
3610 
3611 	dev =  __dev_get_by_index(net, ifm->ifa_index);
3612 	if (dev == NULL)
3613 		return -ENODEV;
3614 
3615 	/* We ignore other flags so far. */
3616 	ifa_flags = ifm->ifa_flags & (IFA_F_NODAD | IFA_F_HOMEADDRESS);
3617 
3618 	ifa = ipv6_get_ifaddr(net, pfx, dev, 1);
3619 	if (ifa == NULL) {
3620 		/*
3621 		 * It would be best to check for !NLM_F_CREATE here but
3622 		 * userspace alreay relies on not having to provide this.
3623 		 */
3624 		return inet6_addr_add(net, ifm->ifa_index, pfx,
3625 				      ifm->ifa_prefixlen, ifa_flags,
3626 				      preferred_lft, valid_lft);
3627 	}
3628 
3629 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
3630 	    !(nlh->nlmsg_flags & NLM_F_REPLACE))
3631 		err = -EEXIST;
3632 	else
3633 		err = inet6_addr_modify(ifa, ifa_flags, preferred_lft, valid_lft);
3634 
3635 	in6_ifa_put(ifa);
3636 
3637 	return err;
3638 }
3639 
3640 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u8 flags,
3641 			  u8 scope, int ifindex)
3642 {
3643 	struct ifaddrmsg *ifm;
3644 
3645 	ifm = nlmsg_data(nlh);
3646 	ifm->ifa_family = AF_INET6;
3647 	ifm->ifa_prefixlen = prefixlen;
3648 	ifm->ifa_flags = flags;
3649 	ifm->ifa_scope = scope;
3650 	ifm->ifa_index = ifindex;
3651 }
3652 
3653 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
3654 			 unsigned long tstamp, u32 preferred, u32 valid)
3655 {
3656 	struct ifa_cacheinfo ci;
3657 
3658 	ci.cstamp = cstamp_delta(cstamp);
3659 	ci.tstamp = cstamp_delta(tstamp);
3660 	ci.ifa_prefered = preferred;
3661 	ci.ifa_valid = valid;
3662 
3663 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
3664 }
3665 
3666 static inline int rt_scope(int ifa_scope)
3667 {
3668 	if (ifa_scope & IFA_HOST)
3669 		return RT_SCOPE_HOST;
3670 	else if (ifa_scope & IFA_LINK)
3671 		return RT_SCOPE_LINK;
3672 	else if (ifa_scope & IFA_SITE)
3673 		return RT_SCOPE_SITE;
3674 	else
3675 		return RT_SCOPE_UNIVERSE;
3676 }
3677 
3678 static inline int inet6_ifaddr_msgsize(void)
3679 {
3680 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
3681 	       + nla_total_size(16) /* IFA_ADDRESS */
3682 	       + nla_total_size(sizeof(struct ifa_cacheinfo));
3683 }
3684 
3685 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
3686 			     u32 portid, u32 seq, int event, unsigned int flags)
3687 {
3688 	struct nlmsghdr  *nlh;
3689 	u32 preferred, valid;
3690 
3691 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
3692 	if (nlh == NULL)
3693 		return -EMSGSIZE;
3694 
3695 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
3696 		      ifa->idev->dev->ifindex);
3697 
3698 	if (!(ifa->flags&IFA_F_PERMANENT)) {
3699 		preferred = ifa->prefered_lft;
3700 		valid = ifa->valid_lft;
3701 		if (preferred != INFINITY_LIFE_TIME) {
3702 			long tval = (jiffies - ifa->tstamp)/HZ;
3703 			if (preferred > tval)
3704 				preferred -= tval;
3705 			else
3706 				preferred = 0;
3707 			if (valid != INFINITY_LIFE_TIME) {
3708 				if (valid > tval)
3709 					valid -= tval;
3710 				else
3711 					valid = 0;
3712 			}
3713 		}
3714 	} else {
3715 		preferred = INFINITY_LIFE_TIME;
3716 		valid = INFINITY_LIFE_TIME;
3717 	}
3718 
3719 	if (nla_put(skb, IFA_ADDRESS, 16, &ifa->addr) < 0 ||
3720 	    put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0) {
3721 		nlmsg_cancel(skb, nlh);
3722 		return -EMSGSIZE;
3723 	}
3724 
3725 	return nlmsg_end(skb, nlh);
3726 }
3727 
3728 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
3729 				u32 portid, u32 seq, int event, u16 flags)
3730 {
3731 	struct nlmsghdr  *nlh;
3732 	u8 scope = RT_SCOPE_UNIVERSE;
3733 	int ifindex = ifmca->idev->dev->ifindex;
3734 
3735 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
3736 		scope = RT_SCOPE_SITE;
3737 
3738 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
3739 	if (nlh == NULL)
3740 		return -EMSGSIZE;
3741 
3742 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
3743 	if (nla_put(skb, IFA_MULTICAST, 16, &ifmca->mca_addr) < 0 ||
3744 	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
3745 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
3746 		nlmsg_cancel(skb, nlh);
3747 		return -EMSGSIZE;
3748 	}
3749 
3750 	return nlmsg_end(skb, nlh);
3751 }
3752 
3753 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
3754 				u32 portid, u32 seq, int event, unsigned int flags)
3755 {
3756 	struct nlmsghdr  *nlh;
3757 	u8 scope = RT_SCOPE_UNIVERSE;
3758 	int ifindex = ifaca->aca_idev->dev->ifindex;
3759 
3760 	if (ipv6_addr_scope(&ifaca->aca_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_ANYCAST, 16, &ifaca->aca_addr) < 0 ||
3769 	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_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 enum addr_type_t {
3779 	UNICAST_ADDR,
3780 	MULTICAST_ADDR,
3781 	ANYCAST_ADDR,
3782 };
3783 
3784 /* called with rcu_read_lock() */
3785 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
3786 			  struct netlink_callback *cb, enum addr_type_t type,
3787 			  int s_ip_idx, int *p_ip_idx)
3788 {
3789 	struct ifmcaddr6 *ifmca;
3790 	struct ifacaddr6 *ifaca;
3791 	int err = 1;
3792 	int ip_idx = *p_ip_idx;
3793 
3794 	read_lock_bh(&idev->lock);
3795 	switch (type) {
3796 	case UNICAST_ADDR: {
3797 		struct inet6_ifaddr *ifa;
3798 
3799 		/* unicast address incl. temp addr */
3800 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
3801 			if (++ip_idx < s_ip_idx)
3802 				continue;
3803 			err = inet6_fill_ifaddr(skb, ifa,
3804 						NETLINK_CB(cb->skb).portid,
3805 						cb->nlh->nlmsg_seq,
3806 						RTM_NEWADDR,
3807 						NLM_F_MULTI);
3808 			if (err <= 0)
3809 				break;
3810 		}
3811 		break;
3812 	}
3813 	case MULTICAST_ADDR:
3814 		/* multicast address */
3815 		for (ifmca = idev->mc_list; ifmca;
3816 		     ifmca = ifmca->next, ip_idx++) {
3817 			if (ip_idx < s_ip_idx)
3818 				continue;
3819 			err = inet6_fill_ifmcaddr(skb, ifmca,
3820 						  NETLINK_CB(cb->skb).portid,
3821 						  cb->nlh->nlmsg_seq,
3822 						  RTM_GETMULTICAST,
3823 						  NLM_F_MULTI);
3824 			if (err <= 0)
3825 				break;
3826 		}
3827 		break;
3828 	case ANYCAST_ADDR:
3829 		/* anycast address */
3830 		for (ifaca = idev->ac_list; ifaca;
3831 		     ifaca = ifaca->aca_next, ip_idx++) {
3832 			if (ip_idx < s_ip_idx)
3833 				continue;
3834 			err = inet6_fill_ifacaddr(skb, ifaca,
3835 						  NETLINK_CB(cb->skb).portid,
3836 						  cb->nlh->nlmsg_seq,
3837 						  RTM_GETANYCAST,
3838 						  NLM_F_MULTI);
3839 			if (err <= 0)
3840 				break;
3841 		}
3842 		break;
3843 	default:
3844 		break;
3845 	}
3846 	read_unlock_bh(&idev->lock);
3847 	*p_ip_idx = ip_idx;
3848 	return err;
3849 }
3850 
3851 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
3852 			   enum addr_type_t type)
3853 {
3854 	struct net *net = sock_net(skb->sk);
3855 	int h, s_h;
3856 	int idx, ip_idx;
3857 	int s_idx, s_ip_idx;
3858 	struct net_device *dev;
3859 	struct inet6_dev *idev;
3860 	struct hlist_head *head;
3861 
3862 	s_h = cb->args[0];
3863 	s_idx = idx = cb->args[1];
3864 	s_ip_idx = ip_idx = cb->args[2];
3865 
3866 	rcu_read_lock();
3867 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
3868 		idx = 0;
3869 		head = &net->dev_index_head[h];
3870 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
3871 			if (idx < s_idx)
3872 				goto cont;
3873 			if (h > s_h || idx > s_idx)
3874 				s_ip_idx = 0;
3875 			ip_idx = 0;
3876 			idev = __in6_dev_get(dev);
3877 			if (!idev)
3878 				goto cont;
3879 
3880 			if (in6_dump_addrs(idev, skb, cb, type,
3881 					   s_ip_idx, &ip_idx) <= 0)
3882 				goto done;
3883 cont:
3884 			idx++;
3885 		}
3886 	}
3887 done:
3888 	rcu_read_unlock();
3889 	cb->args[0] = h;
3890 	cb->args[1] = idx;
3891 	cb->args[2] = ip_idx;
3892 
3893 	return skb->len;
3894 }
3895 
3896 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
3897 {
3898 	enum addr_type_t type = UNICAST_ADDR;
3899 
3900 	return inet6_dump_addr(skb, cb, type);
3901 }
3902 
3903 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
3904 {
3905 	enum addr_type_t type = MULTICAST_ADDR;
3906 
3907 	return inet6_dump_addr(skb, cb, type);
3908 }
3909 
3910 
3911 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
3912 {
3913 	enum addr_type_t type = ANYCAST_ADDR;
3914 
3915 	return inet6_dump_addr(skb, cb, type);
3916 }
3917 
3918 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
3919 			     void *arg)
3920 {
3921 	struct net *net = sock_net(in_skb->sk);
3922 	struct ifaddrmsg *ifm;
3923 	struct nlattr *tb[IFA_MAX+1];
3924 	struct in6_addr *addr = NULL;
3925 	struct net_device *dev = NULL;
3926 	struct inet6_ifaddr *ifa;
3927 	struct sk_buff *skb;
3928 	int err;
3929 
3930 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
3931 	if (err < 0)
3932 		goto errout;
3933 
3934 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL]);
3935 	if (addr == NULL) {
3936 		err = -EINVAL;
3937 		goto errout;
3938 	}
3939 
3940 	ifm = nlmsg_data(nlh);
3941 	if (ifm->ifa_index)
3942 		dev = __dev_get_by_index(net, ifm->ifa_index);
3943 
3944 	ifa = ipv6_get_ifaddr(net, addr, dev, 1);
3945 	if (!ifa) {
3946 		err = -EADDRNOTAVAIL;
3947 		goto errout;
3948 	}
3949 
3950 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
3951 	if (!skb) {
3952 		err = -ENOBUFS;
3953 		goto errout_ifa;
3954 	}
3955 
3956 	err = inet6_fill_ifaddr(skb, ifa, NETLINK_CB(in_skb).portid,
3957 				nlh->nlmsg_seq, RTM_NEWADDR, 0);
3958 	if (err < 0) {
3959 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
3960 		WARN_ON(err == -EMSGSIZE);
3961 		kfree_skb(skb);
3962 		goto errout_ifa;
3963 	}
3964 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
3965 errout_ifa:
3966 	in6_ifa_put(ifa);
3967 errout:
3968 	return err;
3969 }
3970 
3971 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
3972 {
3973 	struct sk_buff *skb;
3974 	struct net *net = dev_net(ifa->idev->dev);
3975 	int err = -ENOBUFS;
3976 
3977 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
3978 	if (skb == NULL)
3979 		goto errout;
3980 
3981 	err = inet6_fill_ifaddr(skb, ifa, 0, 0, event, 0);
3982 	if (err < 0) {
3983 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
3984 		WARN_ON(err == -EMSGSIZE);
3985 		kfree_skb(skb);
3986 		goto errout;
3987 	}
3988 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
3989 	return;
3990 errout:
3991 	if (err < 0)
3992 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
3993 }
3994 
3995 static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
3996 				__s32 *array, int bytes)
3997 {
3998 	BUG_ON(bytes < (DEVCONF_MAX * 4));
3999 
4000 	memset(array, 0, bytes);
4001 	array[DEVCONF_FORWARDING] = cnf->forwarding;
4002 	array[DEVCONF_HOPLIMIT] = cnf->hop_limit;
4003 	array[DEVCONF_MTU6] = cnf->mtu6;
4004 	array[DEVCONF_ACCEPT_RA] = cnf->accept_ra;
4005 	array[DEVCONF_ACCEPT_REDIRECTS] = cnf->accept_redirects;
4006 	array[DEVCONF_AUTOCONF] = cnf->autoconf;
4007 	array[DEVCONF_DAD_TRANSMITS] = cnf->dad_transmits;
4008 	array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
4009 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
4010 		jiffies_to_msecs(cnf->rtr_solicit_interval);
4011 	array[DEVCONF_RTR_SOLICIT_DELAY] =
4012 		jiffies_to_msecs(cnf->rtr_solicit_delay);
4013 	array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;
4014 #ifdef CONFIG_IPV6_PRIVACY
4015 	array[DEVCONF_USE_TEMPADDR] = cnf->use_tempaddr;
4016 	array[DEVCONF_TEMP_VALID_LFT] = cnf->temp_valid_lft;
4017 	array[DEVCONF_TEMP_PREFERED_LFT] = cnf->temp_prefered_lft;
4018 	array[DEVCONF_REGEN_MAX_RETRY] = cnf->regen_max_retry;
4019 	array[DEVCONF_MAX_DESYNC_FACTOR] = cnf->max_desync_factor;
4020 #endif
4021 	array[DEVCONF_MAX_ADDRESSES] = cnf->max_addresses;
4022 	array[DEVCONF_ACCEPT_RA_DEFRTR] = cnf->accept_ra_defrtr;
4023 	array[DEVCONF_ACCEPT_RA_PINFO] = cnf->accept_ra_pinfo;
4024 #ifdef CONFIG_IPV6_ROUTER_PREF
4025 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = cnf->accept_ra_rtr_pref;
4026 	array[DEVCONF_RTR_PROBE_INTERVAL] =
4027 		jiffies_to_msecs(cnf->rtr_probe_interval);
4028 #ifdef CONFIG_IPV6_ROUTE_INFO
4029 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
4030 #endif
4031 #endif
4032 	array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
4033 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
4034 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
4035 	array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
4036 #endif
4037 #ifdef CONFIG_IPV6_MROUTE
4038 	array[DEVCONF_MC_FORWARDING] = cnf->mc_forwarding;
4039 #endif
4040 	array[DEVCONF_DISABLE_IPV6] = cnf->disable_ipv6;
4041 	array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad;
4042 	array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao;
4043 	array[DEVCONF_NDISC_NOTIFY] = cnf->ndisc_notify;
4044 }
4045 
4046 static inline size_t inet6_ifla6_size(void)
4047 {
4048 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
4049 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
4050 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
4051 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
4052 	     + nla_total_size(ICMP6_MIB_MAX * 8); /* IFLA_INET6_ICMP6STATS */
4053 }
4054 
4055 static inline size_t inet6_if_nlmsg_size(void)
4056 {
4057 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
4058 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
4059 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
4060 	       + nla_total_size(4) /* IFLA_MTU */
4061 	       + nla_total_size(4) /* IFLA_LINK */
4062 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
4063 }
4064 
4065 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
4066 				      int items, int bytes)
4067 {
4068 	int i;
4069 	int pad = bytes - sizeof(u64) * items;
4070 	BUG_ON(pad < 0);
4071 
4072 	/* Use put_unaligned() because stats may not be aligned for u64. */
4073 	put_unaligned(items, &stats[0]);
4074 	for (i = 1; i < items; i++)
4075 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
4076 
4077 	memset(&stats[items], 0, pad);
4078 }
4079 
4080 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu **mib,
4081 				      int items, int bytes, size_t syncpoff)
4082 {
4083 	int i;
4084 	int pad = bytes - sizeof(u64) * items;
4085 	BUG_ON(pad < 0);
4086 
4087 	/* Use put_unaligned() because stats may not be aligned for u64. */
4088 	put_unaligned(items, &stats[0]);
4089 	for (i = 1; i < items; i++)
4090 		put_unaligned(snmp_fold_field64(mib, i, syncpoff), &stats[i]);
4091 
4092 	memset(&stats[items], 0, pad);
4093 }
4094 
4095 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
4096 			     int bytes)
4097 {
4098 	switch (attrtype) {
4099 	case IFLA_INET6_STATS:
4100 		__snmp6_fill_stats64(stats, (void __percpu **)idev->stats.ipv6,
4101 				     IPSTATS_MIB_MAX, bytes, offsetof(struct ipstats_mib, syncp));
4102 		break;
4103 	case IFLA_INET6_ICMP6STATS:
4104 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, ICMP6_MIB_MAX, bytes);
4105 		break;
4106 	}
4107 }
4108 
4109 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev)
4110 {
4111 	struct nlattr *nla;
4112 	struct ifla_cacheinfo ci;
4113 
4114 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, idev->if_flags))
4115 		goto nla_put_failure;
4116 	ci.max_reasm_len = IPV6_MAXPLEN;
4117 	ci.tstamp = cstamp_delta(idev->tstamp);
4118 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
4119 	ci.retrans_time = jiffies_to_msecs(idev->nd_parms->retrans_time);
4120 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
4121 		goto nla_put_failure;
4122 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
4123 	if (nla == NULL)
4124 		goto nla_put_failure;
4125 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
4126 
4127 	/* XXX - MC not implemented */
4128 
4129 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
4130 	if (nla == NULL)
4131 		goto nla_put_failure;
4132 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
4133 
4134 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
4135 	if (nla == NULL)
4136 		goto nla_put_failure;
4137 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
4138 
4139 	return 0;
4140 
4141 nla_put_failure:
4142 	return -EMSGSIZE;
4143 }
4144 
4145 static size_t inet6_get_link_af_size(const struct net_device *dev)
4146 {
4147 	if (!__in6_dev_get(dev))
4148 		return 0;
4149 
4150 	return inet6_ifla6_size();
4151 }
4152 
4153 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev)
4154 {
4155 	struct inet6_dev *idev = __in6_dev_get(dev);
4156 
4157 	if (!idev)
4158 		return -ENODATA;
4159 
4160 	if (inet6_fill_ifla6_attrs(skb, idev) < 0)
4161 		return -EMSGSIZE;
4162 
4163 	return 0;
4164 }
4165 
4166 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
4167 			     u32 portid, u32 seq, int event, unsigned int flags)
4168 {
4169 	struct net_device *dev = idev->dev;
4170 	struct ifinfomsg *hdr;
4171 	struct nlmsghdr *nlh;
4172 	void *protoinfo;
4173 
4174 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
4175 	if (nlh == NULL)
4176 		return -EMSGSIZE;
4177 
4178 	hdr = nlmsg_data(nlh);
4179 	hdr->ifi_family = AF_INET6;
4180 	hdr->__ifi_pad = 0;
4181 	hdr->ifi_type = dev->type;
4182 	hdr->ifi_index = dev->ifindex;
4183 	hdr->ifi_flags = dev_get_flags(dev);
4184 	hdr->ifi_change = 0;
4185 
4186 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
4187 	    (dev->addr_len &&
4188 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
4189 	    nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
4190 	    (dev->ifindex != dev->iflink &&
4191 	     nla_put_u32(skb, IFLA_LINK, dev->iflink)))
4192 		goto nla_put_failure;
4193 	protoinfo = nla_nest_start(skb, IFLA_PROTINFO);
4194 	if (protoinfo == NULL)
4195 		goto nla_put_failure;
4196 
4197 	if (inet6_fill_ifla6_attrs(skb, idev) < 0)
4198 		goto nla_put_failure;
4199 
4200 	nla_nest_end(skb, protoinfo);
4201 	return nlmsg_end(skb, nlh);
4202 
4203 nla_put_failure:
4204 	nlmsg_cancel(skb, nlh);
4205 	return -EMSGSIZE;
4206 }
4207 
4208 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
4209 {
4210 	struct net *net = sock_net(skb->sk);
4211 	int h, s_h;
4212 	int idx = 0, s_idx;
4213 	struct net_device *dev;
4214 	struct inet6_dev *idev;
4215 	struct hlist_head *head;
4216 
4217 	s_h = cb->args[0];
4218 	s_idx = cb->args[1];
4219 
4220 	rcu_read_lock();
4221 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
4222 		idx = 0;
4223 		head = &net->dev_index_head[h];
4224 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
4225 			if (idx < s_idx)
4226 				goto cont;
4227 			idev = __in6_dev_get(dev);
4228 			if (!idev)
4229 				goto cont;
4230 			if (inet6_fill_ifinfo(skb, idev,
4231 					      NETLINK_CB(cb->skb).portid,
4232 					      cb->nlh->nlmsg_seq,
4233 					      RTM_NEWLINK, NLM_F_MULTI) <= 0)
4234 				goto out;
4235 cont:
4236 			idx++;
4237 		}
4238 	}
4239 out:
4240 	rcu_read_unlock();
4241 	cb->args[1] = idx;
4242 	cb->args[0] = h;
4243 
4244 	return skb->len;
4245 }
4246 
4247 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
4248 {
4249 	struct sk_buff *skb;
4250 	struct net *net = dev_net(idev->dev);
4251 	int err = -ENOBUFS;
4252 
4253 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
4254 	if (skb == NULL)
4255 		goto errout;
4256 
4257 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
4258 	if (err < 0) {
4259 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
4260 		WARN_ON(err == -EMSGSIZE);
4261 		kfree_skb(skb);
4262 		goto errout;
4263 	}
4264 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
4265 	return;
4266 errout:
4267 	if (err < 0)
4268 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
4269 }
4270 
4271 static inline size_t inet6_prefix_nlmsg_size(void)
4272 {
4273 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
4274 	       + nla_total_size(sizeof(struct in6_addr))
4275 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
4276 }
4277 
4278 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
4279 			     struct prefix_info *pinfo, u32 portid, u32 seq,
4280 			     int event, unsigned int flags)
4281 {
4282 	struct prefixmsg *pmsg;
4283 	struct nlmsghdr *nlh;
4284 	struct prefix_cacheinfo	ci;
4285 
4286 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
4287 	if (nlh == NULL)
4288 		return -EMSGSIZE;
4289 
4290 	pmsg = nlmsg_data(nlh);
4291 	pmsg->prefix_family = AF_INET6;
4292 	pmsg->prefix_pad1 = 0;
4293 	pmsg->prefix_pad2 = 0;
4294 	pmsg->prefix_ifindex = idev->dev->ifindex;
4295 	pmsg->prefix_len = pinfo->prefix_len;
4296 	pmsg->prefix_type = pinfo->type;
4297 	pmsg->prefix_pad3 = 0;
4298 	pmsg->prefix_flags = 0;
4299 	if (pinfo->onlink)
4300 		pmsg->prefix_flags |= IF_PREFIX_ONLINK;
4301 	if (pinfo->autoconf)
4302 		pmsg->prefix_flags |= IF_PREFIX_AUTOCONF;
4303 
4304 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
4305 		goto nla_put_failure;
4306 	ci.preferred_time = ntohl(pinfo->prefered);
4307 	ci.valid_time = ntohl(pinfo->valid);
4308 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
4309 		goto nla_put_failure;
4310 	return nlmsg_end(skb, nlh);
4311 
4312 nla_put_failure:
4313 	nlmsg_cancel(skb, nlh);
4314 	return -EMSGSIZE;
4315 }
4316 
4317 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
4318 			 struct prefix_info *pinfo)
4319 {
4320 	struct sk_buff *skb;
4321 	struct net *net = dev_net(idev->dev);
4322 	int err = -ENOBUFS;
4323 
4324 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
4325 	if (skb == NULL)
4326 		goto errout;
4327 
4328 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
4329 	if (err < 0) {
4330 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
4331 		WARN_ON(err == -EMSGSIZE);
4332 		kfree_skb(skb);
4333 		goto errout;
4334 	}
4335 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
4336 	return;
4337 errout:
4338 	if (err < 0)
4339 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
4340 }
4341 
4342 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
4343 {
4344 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
4345 
4346 	switch (event) {
4347 	case RTM_NEWADDR:
4348 		/*
4349 		 * If the address was optimistic
4350 		 * we inserted the route at the start of
4351 		 * our DAD process, so we don't need
4352 		 * to do it again
4353 		 */
4354 		if (!(ifp->rt->rt6i_node))
4355 			ip6_ins_rt(ifp->rt);
4356 		if (ifp->idev->cnf.forwarding)
4357 			addrconf_join_anycast(ifp);
4358 		break;
4359 	case RTM_DELADDR:
4360 		if (ifp->idev->cnf.forwarding)
4361 			addrconf_leave_anycast(ifp);
4362 		addrconf_leave_solict(ifp->idev, &ifp->addr);
4363 		dst_hold(&ifp->rt->dst);
4364 
4365 		if (ip6_del_rt(ifp->rt))
4366 			dst_free(&ifp->rt->dst);
4367 		break;
4368 	}
4369 }
4370 
4371 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
4372 {
4373 	rcu_read_lock_bh();
4374 	if (likely(ifp->idev->dead == 0))
4375 		__ipv6_ifa_notify(event, ifp);
4376 	rcu_read_unlock_bh();
4377 }
4378 
4379 #ifdef CONFIG_SYSCTL
4380 
4381 static
4382 int addrconf_sysctl_forward(ctl_table *ctl, int write,
4383 			   void __user *buffer, size_t *lenp, loff_t *ppos)
4384 {
4385 	int *valp = ctl->data;
4386 	int val = *valp;
4387 	loff_t pos = *ppos;
4388 	ctl_table lctl;
4389 	int ret;
4390 
4391 	/*
4392 	 * ctl->data points to idev->cnf.forwarding, we should
4393 	 * not modify it until we get the rtnl lock.
4394 	 */
4395 	lctl = *ctl;
4396 	lctl.data = &val;
4397 
4398 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
4399 
4400 	if (write)
4401 		ret = addrconf_fixup_forwarding(ctl, valp, val);
4402 	if (ret)
4403 		*ppos = pos;
4404 	return ret;
4405 }
4406 
4407 static void dev_disable_change(struct inet6_dev *idev)
4408 {
4409 	if (!idev || !idev->dev)
4410 		return;
4411 
4412 	if (idev->cnf.disable_ipv6)
4413 		addrconf_notify(NULL, NETDEV_DOWN, idev->dev);
4414 	else
4415 		addrconf_notify(NULL, NETDEV_UP, idev->dev);
4416 }
4417 
4418 static void addrconf_disable_change(struct net *net, __s32 newf)
4419 {
4420 	struct net_device *dev;
4421 	struct inet6_dev *idev;
4422 
4423 	rcu_read_lock();
4424 	for_each_netdev_rcu(net, dev) {
4425 		idev = __in6_dev_get(dev);
4426 		if (idev) {
4427 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
4428 			idev->cnf.disable_ipv6 = newf;
4429 			if (changed)
4430 				dev_disable_change(idev);
4431 		}
4432 	}
4433 	rcu_read_unlock();
4434 }
4435 
4436 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
4437 {
4438 	struct net *net;
4439 	int old;
4440 
4441 	if (!rtnl_trylock())
4442 		return restart_syscall();
4443 
4444 	net = (struct net *)table->extra2;
4445 	old = *p;
4446 	*p = newf;
4447 
4448 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
4449 		rtnl_unlock();
4450 		return 0;
4451 	}
4452 
4453 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
4454 		net->ipv6.devconf_dflt->disable_ipv6 = newf;
4455 		addrconf_disable_change(net, newf);
4456 	} else if ((!newf) ^ (!old))
4457 		dev_disable_change((struct inet6_dev *)table->extra1);
4458 
4459 	rtnl_unlock();
4460 	return 0;
4461 }
4462 
4463 static
4464 int addrconf_sysctl_disable(ctl_table *ctl, int write,
4465 			    void __user *buffer, size_t *lenp, loff_t *ppos)
4466 {
4467 	int *valp = ctl->data;
4468 	int val = *valp;
4469 	loff_t pos = *ppos;
4470 	ctl_table lctl;
4471 	int ret;
4472 
4473 	/*
4474 	 * ctl->data points to idev->cnf.disable_ipv6, we should
4475 	 * not modify it until we get the rtnl lock.
4476 	 */
4477 	lctl = *ctl;
4478 	lctl.data = &val;
4479 
4480 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
4481 
4482 	if (write)
4483 		ret = addrconf_disable_ipv6(ctl, valp, val);
4484 	if (ret)
4485 		*ppos = pos;
4486 	return ret;
4487 }
4488 
4489 static struct addrconf_sysctl_table
4490 {
4491 	struct ctl_table_header *sysctl_header;
4492 	ctl_table addrconf_vars[DEVCONF_MAX+1];
4493 } addrconf_sysctl __read_mostly = {
4494 	.sysctl_header = NULL,
4495 	.addrconf_vars = {
4496 		{
4497 			.procname	= "forwarding",
4498 			.data		= &ipv6_devconf.forwarding,
4499 			.maxlen		= sizeof(int),
4500 			.mode		= 0644,
4501 			.proc_handler	= addrconf_sysctl_forward,
4502 		},
4503 		{
4504 			.procname	= "hop_limit",
4505 			.data		= &ipv6_devconf.hop_limit,
4506 			.maxlen		= sizeof(int),
4507 			.mode		= 0644,
4508 			.proc_handler	= proc_dointvec,
4509 		},
4510 		{
4511 			.procname	= "mtu",
4512 			.data		= &ipv6_devconf.mtu6,
4513 			.maxlen		= sizeof(int),
4514 			.mode		= 0644,
4515 			.proc_handler	= proc_dointvec,
4516 		},
4517 		{
4518 			.procname	= "accept_ra",
4519 			.data		= &ipv6_devconf.accept_ra,
4520 			.maxlen		= sizeof(int),
4521 			.mode		= 0644,
4522 			.proc_handler	= proc_dointvec,
4523 		},
4524 		{
4525 			.procname	= "accept_redirects",
4526 			.data		= &ipv6_devconf.accept_redirects,
4527 			.maxlen		= sizeof(int),
4528 			.mode		= 0644,
4529 			.proc_handler	= proc_dointvec,
4530 		},
4531 		{
4532 			.procname	= "autoconf",
4533 			.data		= &ipv6_devconf.autoconf,
4534 			.maxlen		= sizeof(int),
4535 			.mode		= 0644,
4536 			.proc_handler	= proc_dointvec,
4537 		},
4538 		{
4539 			.procname	= "dad_transmits",
4540 			.data		= &ipv6_devconf.dad_transmits,
4541 			.maxlen		= sizeof(int),
4542 			.mode		= 0644,
4543 			.proc_handler	= proc_dointvec,
4544 		},
4545 		{
4546 			.procname	= "router_solicitations",
4547 			.data		= &ipv6_devconf.rtr_solicits,
4548 			.maxlen		= sizeof(int),
4549 			.mode		= 0644,
4550 			.proc_handler	= proc_dointvec,
4551 		},
4552 		{
4553 			.procname	= "router_solicitation_interval",
4554 			.data		= &ipv6_devconf.rtr_solicit_interval,
4555 			.maxlen		= sizeof(int),
4556 			.mode		= 0644,
4557 			.proc_handler	= proc_dointvec_jiffies,
4558 		},
4559 		{
4560 			.procname	= "router_solicitation_delay",
4561 			.data		= &ipv6_devconf.rtr_solicit_delay,
4562 			.maxlen		= sizeof(int),
4563 			.mode		= 0644,
4564 			.proc_handler	= proc_dointvec_jiffies,
4565 		},
4566 		{
4567 			.procname	= "force_mld_version",
4568 			.data		= &ipv6_devconf.force_mld_version,
4569 			.maxlen		= sizeof(int),
4570 			.mode		= 0644,
4571 			.proc_handler	= proc_dointvec,
4572 		},
4573 #ifdef CONFIG_IPV6_PRIVACY
4574 		{
4575 			.procname	= "use_tempaddr",
4576 			.data		= &ipv6_devconf.use_tempaddr,
4577 			.maxlen		= sizeof(int),
4578 			.mode		= 0644,
4579 			.proc_handler	= proc_dointvec,
4580 		},
4581 		{
4582 			.procname	= "temp_valid_lft",
4583 			.data		= &ipv6_devconf.temp_valid_lft,
4584 			.maxlen		= sizeof(int),
4585 			.mode		= 0644,
4586 			.proc_handler	= proc_dointvec,
4587 		},
4588 		{
4589 			.procname	= "temp_prefered_lft",
4590 			.data		= &ipv6_devconf.temp_prefered_lft,
4591 			.maxlen		= sizeof(int),
4592 			.mode		= 0644,
4593 			.proc_handler	= proc_dointvec,
4594 		},
4595 		{
4596 			.procname	= "regen_max_retry",
4597 			.data		= &ipv6_devconf.regen_max_retry,
4598 			.maxlen		= sizeof(int),
4599 			.mode		= 0644,
4600 			.proc_handler	= proc_dointvec,
4601 		},
4602 		{
4603 			.procname	= "max_desync_factor",
4604 			.data		= &ipv6_devconf.max_desync_factor,
4605 			.maxlen		= sizeof(int),
4606 			.mode		= 0644,
4607 			.proc_handler	= proc_dointvec,
4608 		},
4609 #endif
4610 		{
4611 			.procname	= "max_addresses",
4612 			.data		= &ipv6_devconf.max_addresses,
4613 			.maxlen		= sizeof(int),
4614 			.mode		= 0644,
4615 			.proc_handler	= proc_dointvec,
4616 		},
4617 		{
4618 			.procname	= "accept_ra_defrtr",
4619 			.data		= &ipv6_devconf.accept_ra_defrtr,
4620 			.maxlen		= sizeof(int),
4621 			.mode		= 0644,
4622 			.proc_handler	= proc_dointvec,
4623 		},
4624 		{
4625 			.procname	= "accept_ra_pinfo",
4626 			.data		= &ipv6_devconf.accept_ra_pinfo,
4627 			.maxlen		= sizeof(int),
4628 			.mode		= 0644,
4629 			.proc_handler	= proc_dointvec,
4630 		},
4631 #ifdef CONFIG_IPV6_ROUTER_PREF
4632 		{
4633 			.procname	= "accept_ra_rtr_pref",
4634 			.data		= &ipv6_devconf.accept_ra_rtr_pref,
4635 			.maxlen		= sizeof(int),
4636 			.mode		= 0644,
4637 			.proc_handler	= proc_dointvec,
4638 		},
4639 		{
4640 			.procname	= "router_probe_interval",
4641 			.data		= &ipv6_devconf.rtr_probe_interval,
4642 			.maxlen		= sizeof(int),
4643 			.mode		= 0644,
4644 			.proc_handler	= proc_dointvec_jiffies,
4645 		},
4646 #ifdef CONFIG_IPV6_ROUTE_INFO
4647 		{
4648 			.procname	= "accept_ra_rt_info_max_plen",
4649 			.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
4650 			.maxlen		= sizeof(int),
4651 			.mode		= 0644,
4652 			.proc_handler	= proc_dointvec,
4653 		},
4654 #endif
4655 #endif
4656 		{
4657 			.procname	= "proxy_ndp",
4658 			.data		= &ipv6_devconf.proxy_ndp,
4659 			.maxlen		= sizeof(int),
4660 			.mode		= 0644,
4661 			.proc_handler	= proc_dointvec,
4662 		},
4663 		{
4664 			.procname	= "accept_source_route",
4665 			.data		= &ipv6_devconf.accept_source_route,
4666 			.maxlen		= sizeof(int),
4667 			.mode		= 0644,
4668 			.proc_handler	= proc_dointvec,
4669 		},
4670 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
4671 		{
4672 			.procname       = "optimistic_dad",
4673 			.data           = &ipv6_devconf.optimistic_dad,
4674 			.maxlen         = sizeof(int),
4675 			.mode           = 0644,
4676 			.proc_handler   = proc_dointvec,
4677 
4678 		},
4679 #endif
4680 #ifdef CONFIG_IPV6_MROUTE
4681 		{
4682 			.procname	= "mc_forwarding",
4683 			.data		= &ipv6_devconf.mc_forwarding,
4684 			.maxlen		= sizeof(int),
4685 			.mode		= 0444,
4686 			.proc_handler	= proc_dointvec,
4687 		},
4688 #endif
4689 		{
4690 			.procname	= "disable_ipv6",
4691 			.data		= &ipv6_devconf.disable_ipv6,
4692 			.maxlen		= sizeof(int),
4693 			.mode		= 0644,
4694 			.proc_handler	= addrconf_sysctl_disable,
4695 		},
4696 		{
4697 			.procname	= "accept_dad",
4698 			.data		= &ipv6_devconf.accept_dad,
4699 			.maxlen		= sizeof(int),
4700 			.mode		= 0644,
4701 			.proc_handler	= proc_dointvec,
4702 		},
4703 		{
4704 			.procname       = "force_tllao",
4705 			.data           = &ipv6_devconf.force_tllao,
4706 			.maxlen         = sizeof(int),
4707 			.mode           = 0644,
4708 			.proc_handler   = proc_dointvec
4709 		},
4710 		{
4711 			.procname       = "ndisc_notify",
4712 			.data           = &ipv6_devconf.ndisc_notify,
4713 			.maxlen         = sizeof(int),
4714 			.mode           = 0644,
4715 			.proc_handler   = proc_dointvec
4716 		},
4717 		{
4718 			/* sentinel */
4719 		}
4720 	},
4721 };
4722 
4723 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
4724 		struct inet6_dev *idev, struct ipv6_devconf *p)
4725 {
4726 	int i;
4727 	struct addrconf_sysctl_table *t;
4728 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
4729 
4730 	t = kmemdup(&addrconf_sysctl, sizeof(*t), GFP_KERNEL);
4731 	if (t == NULL)
4732 		goto out;
4733 
4734 	for (i = 0; t->addrconf_vars[i].data; i++) {
4735 		t->addrconf_vars[i].data += (char *)p - (char *)&ipv6_devconf;
4736 		t->addrconf_vars[i].extra1 = idev; /* embedded; no ref */
4737 		t->addrconf_vars[i].extra2 = net;
4738 	}
4739 
4740 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
4741 
4742 	t->sysctl_header = register_net_sysctl(net, path, t->addrconf_vars);
4743 	if (t->sysctl_header == NULL)
4744 		goto free;
4745 
4746 	p->sysctl = t;
4747 	return 0;
4748 
4749 free:
4750 	kfree(t);
4751 out:
4752 	return -ENOBUFS;
4753 }
4754 
4755 static void __addrconf_sysctl_unregister(struct ipv6_devconf *p)
4756 {
4757 	struct addrconf_sysctl_table *t;
4758 
4759 	if (p->sysctl == NULL)
4760 		return;
4761 
4762 	t = p->sysctl;
4763 	p->sysctl = NULL;
4764 	unregister_net_sysctl_table(t->sysctl_header);
4765 	kfree(t);
4766 }
4767 
4768 static void addrconf_sysctl_register(struct inet6_dev *idev)
4769 {
4770 	neigh_sysctl_register(idev->dev, idev->nd_parms, "ipv6",
4771 			      &ndisc_ifinfo_sysctl_change);
4772 	__addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
4773 					idev, &idev->cnf);
4774 }
4775 
4776 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
4777 {
4778 	__addrconf_sysctl_unregister(&idev->cnf);
4779 	neigh_sysctl_unregister(idev->nd_parms);
4780 }
4781 
4782 
4783 #endif
4784 
4785 static int __net_init addrconf_init_net(struct net *net)
4786 {
4787 	int err;
4788 	struct ipv6_devconf *all, *dflt;
4789 
4790 	err = -ENOMEM;
4791 	all = &ipv6_devconf;
4792 	dflt = &ipv6_devconf_dflt;
4793 
4794 	if (!net_eq(net, &init_net)) {
4795 		all = kmemdup(all, sizeof(ipv6_devconf), GFP_KERNEL);
4796 		if (all == NULL)
4797 			goto err_alloc_all;
4798 
4799 		dflt = kmemdup(dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
4800 		if (dflt == NULL)
4801 			goto err_alloc_dflt;
4802 	} else {
4803 		/* these will be inherited by all namespaces */
4804 		dflt->autoconf = ipv6_defaults.autoconf;
4805 		dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
4806 	}
4807 
4808 	net->ipv6.devconf_all = all;
4809 	net->ipv6.devconf_dflt = dflt;
4810 
4811 #ifdef CONFIG_SYSCTL
4812 	err = __addrconf_sysctl_register(net, "all", NULL, all);
4813 	if (err < 0)
4814 		goto err_reg_all;
4815 
4816 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
4817 	if (err < 0)
4818 		goto err_reg_dflt;
4819 #endif
4820 	return 0;
4821 
4822 #ifdef CONFIG_SYSCTL
4823 err_reg_dflt:
4824 	__addrconf_sysctl_unregister(all);
4825 err_reg_all:
4826 	kfree(dflt);
4827 #endif
4828 err_alloc_dflt:
4829 	kfree(all);
4830 err_alloc_all:
4831 	return err;
4832 }
4833 
4834 static void __net_exit addrconf_exit_net(struct net *net)
4835 {
4836 #ifdef CONFIG_SYSCTL
4837 	__addrconf_sysctl_unregister(net->ipv6.devconf_dflt);
4838 	__addrconf_sysctl_unregister(net->ipv6.devconf_all);
4839 #endif
4840 	if (!net_eq(net, &init_net)) {
4841 		kfree(net->ipv6.devconf_dflt);
4842 		kfree(net->ipv6.devconf_all);
4843 	}
4844 }
4845 
4846 static struct pernet_operations addrconf_ops = {
4847 	.init = addrconf_init_net,
4848 	.exit = addrconf_exit_net,
4849 };
4850 
4851 /*
4852  *      Device notifier
4853  */
4854 
4855 int register_inet6addr_notifier(struct notifier_block *nb)
4856 {
4857 	return atomic_notifier_chain_register(&inet6addr_chain, nb);
4858 }
4859 EXPORT_SYMBOL(register_inet6addr_notifier);
4860 
4861 int unregister_inet6addr_notifier(struct notifier_block *nb)
4862 {
4863 	return atomic_notifier_chain_unregister(&inet6addr_chain, nb);
4864 }
4865 EXPORT_SYMBOL(unregister_inet6addr_notifier);
4866 
4867 static struct rtnl_af_ops inet6_ops = {
4868 	.family		  = AF_INET6,
4869 	.fill_link_af	  = inet6_fill_link_af,
4870 	.get_link_af_size = inet6_get_link_af_size,
4871 };
4872 
4873 /*
4874  *	Init / cleanup code
4875  */
4876 
4877 int __init addrconf_init(void)
4878 {
4879 	int i, err;
4880 
4881 	err = ipv6_addr_label_init();
4882 	if (err < 0) {
4883 		pr_crit("%s: cannot initialize default policy table: %d\n",
4884 			__func__, err);
4885 		goto out;
4886 	}
4887 
4888 	err = register_pernet_subsys(&addrconf_ops);
4889 	if (err < 0)
4890 		goto out_addrlabel;
4891 
4892 	/* The addrconf netdev notifier requires that loopback_dev
4893 	 * has it's ipv6 private information allocated and setup
4894 	 * before it can bring up and give link-local addresses
4895 	 * to other devices which are up.
4896 	 *
4897 	 * Unfortunately, loopback_dev is not necessarily the first
4898 	 * entry in the global dev_base list of net devices.  In fact,
4899 	 * it is likely to be the very last entry on that list.
4900 	 * So this causes the notifier registry below to try and
4901 	 * give link-local addresses to all devices besides loopback_dev
4902 	 * first, then loopback_dev, which cases all the non-loopback_dev
4903 	 * devices to fail to get a link-local address.
4904 	 *
4905 	 * So, as a temporary fix, allocate the ipv6 structure for
4906 	 * loopback_dev first by hand.
4907 	 * Longer term, all of the dependencies ipv6 has upon the loopback
4908 	 * device and it being up should be removed.
4909 	 */
4910 	rtnl_lock();
4911 	if (!ipv6_add_dev(init_net.loopback_dev))
4912 		err = -ENOMEM;
4913 	rtnl_unlock();
4914 	if (err)
4915 		goto errlo;
4916 
4917 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
4918 		INIT_HLIST_HEAD(&inet6_addr_lst[i]);
4919 
4920 	register_netdevice_notifier(&ipv6_dev_notf);
4921 
4922 	addrconf_verify(0);
4923 
4924 	err = rtnl_af_register(&inet6_ops);
4925 	if (err < 0)
4926 		goto errout_af;
4927 
4928 	err = __rtnl_register(PF_INET6, RTM_GETLINK, NULL, inet6_dump_ifinfo,
4929 			      NULL);
4930 	if (err < 0)
4931 		goto errout;
4932 
4933 	/* Only the first call to __rtnl_register can fail */
4934 	__rtnl_register(PF_INET6, RTM_NEWADDR, inet6_rtm_newaddr, NULL, NULL);
4935 	__rtnl_register(PF_INET6, RTM_DELADDR, inet6_rtm_deladdr, NULL, NULL);
4936 	__rtnl_register(PF_INET6, RTM_GETADDR, inet6_rtm_getaddr,
4937 			inet6_dump_ifaddr, NULL);
4938 	__rtnl_register(PF_INET6, RTM_GETMULTICAST, NULL,
4939 			inet6_dump_ifmcaddr, NULL);
4940 	__rtnl_register(PF_INET6, RTM_GETANYCAST, NULL,
4941 			inet6_dump_ifacaddr, NULL);
4942 	__rtnl_register(PF_INET6, RTM_GETNETCONF, inet6_netconf_get_devconf,
4943 			NULL, NULL);
4944 
4945 	ipv6_addr_label_rtnl_register();
4946 
4947 	return 0;
4948 errout:
4949 	rtnl_af_unregister(&inet6_ops);
4950 errout_af:
4951 	unregister_netdevice_notifier(&ipv6_dev_notf);
4952 errlo:
4953 	unregister_pernet_subsys(&addrconf_ops);
4954 out_addrlabel:
4955 	ipv6_addr_label_cleanup();
4956 out:
4957 	return err;
4958 }
4959 
4960 void addrconf_cleanup(void)
4961 {
4962 	struct net_device *dev;
4963 	int i;
4964 
4965 	unregister_netdevice_notifier(&ipv6_dev_notf);
4966 	unregister_pernet_subsys(&addrconf_ops);
4967 	ipv6_addr_label_cleanup();
4968 
4969 	rtnl_lock();
4970 
4971 	__rtnl_af_unregister(&inet6_ops);
4972 
4973 	/* clean dev list */
4974 	for_each_netdev(&init_net, dev) {
4975 		if (__in6_dev_get(dev) == NULL)
4976 			continue;
4977 		addrconf_ifdown(dev, 1);
4978 	}
4979 	addrconf_ifdown(init_net.loopback_dev, 2);
4980 
4981 	/*
4982 	 *	Check hash table.
4983 	 */
4984 	spin_lock_bh(&addrconf_hash_lock);
4985 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
4986 		WARN_ON(!hlist_empty(&inet6_addr_lst[i]));
4987 	spin_unlock_bh(&addrconf_hash_lock);
4988 
4989 	del_timer(&addr_chk_timer);
4990 	rtnl_unlock();
4991 }
4992