xref: /linux/net/ipv6/addrconf.c (revision e5c5d22e8dcf7c2d430336cbf8e180bd38e8daf1)
1 /*
2  *	IPv6 Address [auto]configuration
3  *	Linux INET6 implementation
4  *
5  *	Authors:
6  *	Pedro Roque		<roque@di.fc.ul.pt>
7  *	Alexey Kuznetsov	<kuznet@ms2.inr.ac.ru>
8  *
9  *	This program is free software; you can redistribute it and/or
10  *      modify it under the terms of the GNU General Public License
11  *      as published by the Free Software Foundation; either version
12  *      2 of the License, or (at your option) any later version.
13  */
14 
15 /*
16  *	Changes:
17  *
18  *	Janos Farkas			:	delete timer on ifdown
19  *	<chexum@bankinf.banki.hu>
20  *	Andi Kleen			:	kill double kfree on module
21  *						unload.
22  *	Maciej W. Rozycki		:	FDDI support
23  *	sekiya@USAGI			:	Don't send too many RS
24  *						packets.
25  *	yoshfuji@USAGI			:       Fixed interval between DAD
26  *						packets.
27  *	YOSHIFUJI Hideaki @USAGI	:	improved accuracy of
28  *						address validation timer.
29  *	YOSHIFUJI Hideaki @USAGI	:	Privacy Extensions (RFC3041)
30  *						support.
31  *	Yuji SEKIYA @USAGI		:	Don't assign a same IPv6
32  *						address on a same interface.
33  *	YOSHIFUJI Hideaki @USAGI	:	ARCnet support
34  *	YOSHIFUJI Hideaki @USAGI	:	convert /proc/net/if_inet6 to
35  *						seq_file.
36  *	YOSHIFUJI Hideaki @USAGI	:	improved source address
37  *						selection; consider scope,
38  *						status etc.
39  */
40 
41 #define pr_fmt(fmt) "IPv6: " fmt
42 
43 #include <linux/errno.h>
44 #include <linux/types.h>
45 #include <linux/kernel.h>
46 #include <linux/socket.h>
47 #include <linux/sockios.h>
48 #include <linux/net.h>
49 #include <linux/in6.h>
50 #include <linux/netdevice.h>
51 #include <linux/if_addr.h>
52 #include <linux/if_arp.h>
53 #include <linux/if_arcnet.h>
54 #include <linux/if_infiniband.h>
55 #include <linux/route.h>
56 #include <linux/inetdevice.h>
57 #include <linux/init.h>
58 #include <linux/slab.h>
59 #ifdef CONFIG_SYSCTL
60 #include <linux/sysctl.h>
61 #endif
62 #include <linux/capability.h>
63 #include <linux/delay.h>
64 #include <linux/notifier.h>
65 #include <linux/string.h>
66 #include <linux/hash.h>
67 
68 #include <net/net_namespace.h>
69 #include <net/sock.h>
70 #include <net/snmp.h>
71 
72 #include <net/af_ieee802154.h>
73 #include <net/firewire.h>
74 #include <net/ipv6.h>
75 #include <net/protocol.h>
76 #include <net/ndisc.h>
77 #include <net/ip6_route.h>
78 #include <net/addrconf.h>
79 #include <net/tcp.h>
80 #include <net/ip.h>
81 #include <net/netlink.h>
82 #include <net/pkt_sched.h>
83 #include <linux/if_tunnel.h>
84 #include <linux/rtnetlink.h>
85 #include <linux/netconf.h>
86 
87 #ifdef CONFIG_IPV6_PRIVACY
88 #include <linux/random.h>
89 #endif
90 
91 #include <linux/uaccess.h>
92 #include <asm/unaligned.h>
93 
94 #include <linux/proc_fs.h>
95 #include <linux/seq_file.h>
96 #include <linux/export.h>
97 
98 /* Set to 3 to get tracing... */
99 #define ACONF_DEBUG 2
100 
101 #if ACONF_DEBUG >= 3
102 #define ADBG(x) printk x
103 #else
104 #define ADBG(x)
105 #endif
106 
107 #define	INFINITY_LIFE_TIME	0xFFFFFFFF
108 
109 static inline u32 cstamp_delta(unsigned long cstamp)
110 {
111 	return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
112 }
113 
114 #ifdef CONFIG_SYSCTL
115 static void addrconf_sysctl_register(struct inet6_dev *idev);
116 static void addrconf_sysctl_unregister(struct inet6_dev *idev);
117 #else
118 static inline void addrconf_sysctl_register(struct inet6_dev *idev)
119 {
120 }
121 
122 static inline void addrconf_sysctl_unregister(struct inet6_dev *idev)
123 {
124 }
125 #endif
126 
127 #ifdef CONFIG_IPV6_PRIVACY
128 static void __ipv6_regen_rndid(struct inet6_dev *idev);
129 static void __ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr);
130 static void ipv6_regen_rndid(unsigned long data);
131 #endif
132 
133 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev);
134 static int ipv6_count_addresses(struct inet6_dev *idev);
135 
136 /*
137  *	Configured unicast address hash table
138  */
139 static struct hlist_head inet6_addr_lst[IN6_ADDR_HSIZE];
140 static DEFINE_SPINLOCK(addrconf_hash_lock);
141 
142 static void addrconf_verify(unsigned long);
143 
144 static DEFINE_TIMER(addr_chk_timer, addrconf_verify, 0, 0);
145 static DEFINE_SPINLOCK(addrconf_verify_lock);
146 
147 static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
148 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
149 
150 static void addrconf_type_change(struct net_device *dev,
151 				 unsigned long event);
152 static int addrconf_ifdown(struct net_device *dev, int how);
153 
154 static struct rt6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
155 						  int plen,
156 						  const struct net_device *dev,
157 						  u32 flags, u32 noflags);
158 
159 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
160 static void addrconf_dad_timer(unsigned long data);
161 static void addrconf_dad_completed(struct inet6_ifaddr *ifp);
162 static void addrconf_dad_run(struct inet6_dev *idev);
163 static void addrconf_rs_timer(unsigned long data);
164 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
165 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
166 
167 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
168 				struct prefix_info *pinfo);
169 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
170 			       struct net_device *dev);
171 
172 static ATOMIC_NOTIFIER_HEAD(inet6addr_chain);
173 
174 static struct ipv6_devconf ipv6_devconf __read_mostly = {
175 	.forwarding		= 0,
176 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
177 	.mtu6			= IPV6_MIN_MTU,
178 	.accept_ra		= 1,
179 	.accept_redirects	= 1,
180 	.autoconf		= 1,
181 	.force_mld_version	= 0,
182 	.dad_transmits		= 1,
183 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
184 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
185 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
186 #ifdef CONFIG_IPV6_PRIVACY
187 	.use_tempaddr 		= 0,
188 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
189 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
190 	.regen_max_retry	= REGEN_MAX_RETRY,
191 	.max_desync_factor	= MAX_DESYNC_FACTOR,
192 #endif
193 	.max_addresses		= IPV6_MAX_ADDRESSES,
194 	.accept_ra_defrtr	= 1,
195 	.accept_ra_pinfo	= 1,
196 #ifdef CONFIG_IPV6_ROUTER_PREF
197 	.accept_ra_rtr_pref	= 1,
198 	.rtr_probe_interval	= 60 * HZ,
199 #ifdef CONFIG_IPV6_ROUTE_INFO
200 	.accept_ra_rt_info_max_plen = 0,
201 #endif
202 #endif
203 	.proxy_ndp		= 0,
204 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
205 	.disable_ipv6		= 0,
206 	.accept_dad		= 1,
207 };
208 
209 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
210 	.forwarding		= 0,
211 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
212 	.mtu6			= IPV6_MIN_MTU,
213 	.accept_ra		= 1,
214 	.accept_redirects	= 1,
215 	.autoconf		= 1,
216 	.dad_transmits		= 1,
217 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
218 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
219 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
220 #ifdef CONFIG_IPV6_PRIVACY
221 	.use_tempaddr		= 0,
222 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
223 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
224 	.regen_max_retry	= REGEN_MAX_RETRY,
225 	.max_desync_factor	= MAX_DESYNC_FACTOR,
226 #endif
227 	.max_addresses		= IPV6_MAX_ADDRESSES,
228 	.accept_ra_defrtr	= 1,
229 	.accept_ra_pinfo	= 1,
230 #ifdef CONFIG_IPV6_ROUTER_PREF
231 	.accept_ra_rtr_pref	= 1,
232 	.rtr_probe_interval	= 60 * HZ,
233 #ifdef CONFIG_IPV6_ROUTE_INFO
234 	.accept_ra_rt_info_max_plen = 0,
235 #endif
236 #endif
237 	.proxy_ndp		= 0,
238 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
239 	.disable_ipv6		= 0,
240 	.accept_dad		= 1,
241 };
242 
243 /* IPv6 Wildcard Address and Loopback Address defined by RFC2553 */
244 const struct in6_addr in6addr_any = IN6ADDR_ANY_INIT;
245 const struct in6_addr in6addr_loopback = IN6ADDR_LOOPBACK_INIT;
246 const struct in6_addr in6addr_linklocal_allnodes = IN6ADDR_LINKLOCAL_ALLNODES_INIT;
247 const struct in6_addr in6addr_linklocal_allrouters = IN6ADDR_LINKLOCAL_ALLROUTERS_INIT;
248 const struct in6_addr in6addr_interfacelocal_allnodes = IN6ADDR_INTERFACELOCAL_ALLNODES_INIT;
249 const struct in6_addr in6addr_interfacelocal_allrouters = IN6ADDR_INTERFACELOCAL_ALLROUTERS_INIT;
250 const struct in6_addr in6addr_sitelocal_allrouters = IN6ADDR_SITELOCAL_ALLROUTERS_INIT;
251 
252 /* Check if a valid qdisc is available */
253 static inline bool addrconf_qdisc_ok(const struct net_device *dev)
254 {
255 	return !qdisc_tx_is_noop(dev);
256 }
257 
258 static void addrconf_del_timer(struct inet6_ifaddr *ifp)
259 {
260 	if (del_timer(&ifp->timer))
261 		__in6_ifa_put(ifp);
262 }
263 
264 enum addrconf_timer_t {
265 	AC_NONE,
266 	AC_DAD,
267 	AC_RS,
268 };
269 
270 static void addrconf_mod_timer(struct inet6_ifaddr *ifp,
271 			       enum addrconf_timer_t what,
272 			       unsigned long when)
273 {
274 	if (!del_timer(&ifp->timer))
275 		in6_ifa_hold(ifp);
276 
277 	switch (what) {
278 	case AC_DAD:
279 		ifp->timer.function = addrconf_dad_timer;
280 		break;
281 	case AC_RS:
282 		ifp->timer.function = addrconf_rs_timer;
283 		break;
284 	default:
285 		break;
286 	}
287 	ifp->timer.expires = jiffies + when;
288 	add_timer(&ifp->timer);
289 }
290 
291 static int snmp6_alloc_dev(struct inet6_dev *idev)
292 {
293 	if (snmp_mib_init((void __percpu **)idev->stats.ipv6,
294 			  sizeof(struct ipstats_mib),
295 			  __alignof__(struct ipstats_mib)) < 0)
296 		goto err_ip;
297 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
298 					GFP_KERNEL);
299 	if (!idev->stats.icmpv6dev)
300 		goto err_icmp;
301 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
302 					   GFP_KERNEL);
303 	if (!idev->stats.icmpv6msgdev)
304 		goto err_icmpmsg;
305 
306 	return 0;
307 
308 err_icmpmsg:
309 	kfree(idev->stats.icmpv6dev);
310 err_icmp:
311 	snmp_mib_free((void __percpu **)idev->stats.ipv6);
312 err_ip:
313 	return -ENOMEM;
314 }
315 
316 static void snmp6_free_dev(struct inet6_dev *idev)
317 {
318 	kfree(idev->stats.icmpv6msgdev);
319 	kfree(idev->stats.icmpv6dev);
320 	snmp_mib_free((void __percpu **)idev->stats.ipv6);
321 }
322 
323 /* Nobody refers to this device, we may destroy it. */
324 
325 void in6_dev_finish_destroy(struct inet6_dev *idev)
326 {
327 	struct net_device *dev = idev->dev;
328 
329 	WARN_ON(!list_empty(&idev->addr_list));
330 	WARN_ON(idev->mc_list != NULL);
331 
332 #ifdef NET_REFCNT_DEBUG
333 	pr_debug("%s: %s\n", __func__, dev ? dev->name : "NIL");
334 #endif
335 	dev_put(dev);
336 	if (!idev->dead) {
337 		pr_warn("Freeing alive inet6 device %p\n", idev);
338 		return;
339 	}
340 	snmp6_free_dev(idev);
341 	kfree_rcu(idev, rcu);
342 }
343 EXPORT_SYMBOL(in6_dev_finish_destroy);
344 
345 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
346 {
347 	struct inet6_dev *ndev;
348 
349 	ASSERT_RTNL();
350 
351 	if (dev->mtu < IPV6_MIN_MTU)
352 		return NULL;
353 
354 	ndev = kzalloc(sizeof(struct inet6_dev), GFP_KERNEL);
355 
356 	if (ndev == NULL)
357 		return NULL;
358 
359 	rwlock_init(&ndev->lock);
360 	ndev->dev = dev;
361 	INIT_LIST_HEAD(&ndev->addr_list);
362 
363 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
364 	ndev->cnf.mtu6 = dev->mtu;
365 	ndev->cnf.sysctl = NULL;
366 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
367 	if (ndev->nd_parms == NULL) {
368 		kfree(ndev);
369 		return NULL;
370 	}
371 	if (ndev->cnf.forwarding)
372 		dev_disable_lro(dev);
373 	/* We refer to the device */
374 	dev_hold(dev);
375 
376 	if (snmp6_alloc_dev(ndev) < 0) {
377 		ADBG((KERN_WARNING
378 			"%s: cannot allocate memory for statistics; dev=%s.\n",
379 			__func__, dev->name));
380 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
381 		dev_put(dev);
382 		kfree(ndev);
383 		return NULL;
384 	}
385 
386 	if (snmp6_register_dev(ndev) < 0) {
387 		ADBG((KERN_WARNING
388 			"%s: cannot create /proc/net/dev_snmp6/%s\n",
389 			__func__, dev->name));
390 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
391 		ndev->dead = 1;
392 		in6_dev_finish_destroy(ndev);
393 		return NULL;
394 	}
395 
396 	/* One reference from device.  We must do this before
397 	 * we invoke __ipv6_regen_rndid().
398 	 */
399 	in6_dev_hold(ndev);
400 
401 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
402 		ndev->cnf.accept_dad = -1;
403 
404 #if IS_ENABLED(CONFIG_IPV6_SIT)
405 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
406 		pr_info("%s: Disabled Multicast RS\n", dev->name);
407 		ndev->cnf.rtr_solicits = 0;
408 	}
409 #endif
410 
411 #ifdef CONFIG_IPV6_PRIVACY
412 	INIT_LIST_HEAD(&ndev->tempaddr_list);
413 	setup_timer(&ndev->regen_timer, ipv6_regen_rndid, (unsigned long)ndev);
414 	if ((dev->flags&IFF_LOOPBACK) ||
415 	    dev->type == ARPHRD_TUNNEL ||
416 	    dev->type == ARPHRD_TUNNEL6 ||
417 	    dev->type == ARPHRD_SIT ||
418 	    dev->type == ARPHRD_NONE) {
419 		ndev->cnf.use_tempaddr = -1;
420 	} else {
421 		in6_dev_hold(ndev);
422 		ipv6_regen_rndid((unsigned long) ndev);
423 	}
424 #endif
425 
426 	if (netif_running(dev) && addrconf_qdisc_ok(dev))
427 		ndev->if_flags |= IF_READY;
428 
429 	ipv6_mc_init_dev(ndev);
430 	ndev->tstamp = jiffies;
431 	addrconf_sysctl_register(ndev);
432 	/* protected by rtnl_lock */
433 	rcu_assign_pointer(dev->ip6_ptr, ndev);
434 
435 	/* Join interface-local all-node multicast group */
436 	ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes);
437 
438 	/* Join all-node multicast group */
439 	ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
440 
441 	/* Join all-router multicast group if forwarding is set */
442 	if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
443 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
444 
445 	return ndev;
446 }
447 
448 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
449 {
450 	struct inet6_dev *idev;
451 
452 	ASSERT_RTNL();
453 
454 	idev = __in6_dev_get(dev);
455 	if (!idev) {
456 		idev = ipv6_add_dev(dev);
457 		if (!idev)
458 			return NULL;
459 	}
460 
461 	if (dev->flags&IFF_UP)
462 		ipv6_mc_up(idev);
463 	return idev;
464 }
465 
466 static int inet6_netconf_msgsize_devconf(int type)
467 {
468 	int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
469 		    + nla_total_size(4);	/* NETCONFA_IFINDEX */
470 
471 	/* type -1 is used for ALL */
472 	if (type == -1 || type == NETCONFA_FORWARDING)
473 		size += nla_total_size(4);
474 #ifdef CONFIG_IPV6_MROUTE
475 	if (type == -1 || type == NETCONFA_MC_FORWARDING)
476 		size += nla_total_size(4);
477 #endif
478 
479 	return size;
480 }
481 
482 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
483 				      struct ipv6_devconf *devconf, u32 portid,
484 				      u32 seq, int event, unsigned int flags,
485 				      int type)
486 {
487 	struct nlmsghdr  *nlh;
488 	struct netconfmsg *ncm;
489 
490 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
491 			flags);
492 	if (nlh == NULL)
493 		return -EMSGSIZE;
494 
495 	ncm = nlmsg_data(nlh);
496 	ncm->ncm_family = AF_INET6;
497 
498 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
499 		goto nla_put_failure;
500 
501 	/* type -1 is used for ALL */
502 	if ((type == -1 || type == NETCONFA_FORWARDING) &&
503 	    nla_put_s32(skb, NETCONFA_FORWARDING, devconf->forwarding) < 0)
504 		goto nla_put_failure;
505 #ifdef CONFIG_IPV6_MROUTE
506 	if ((type == -1 || type == NETCONFA_MC_FORWARDING) &&
507 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
508 			devconf->mc_forwarding) < 0)
509 		goto nla_put_failure;
510 #endif
511 	return nlmsg_end(skb, nlh);
512 
513 nla_put_failure:
514 	nlmsg_cancel(skb, nlh);
515 	return -EMSGSIZE;
516 }
517 
518 void inet6_netconf_notify_devconf(struct net *net, int type, int ifindex,
519 				  struct ipv6_devconf *devconf)
520 {
521 	struct sk_buff *skb;
522 	int err = -ENOBUFS;
523 
524 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_ATOMIC);
525 	if (skb == NULL)
526 		goto errout;
527 
528 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
529 					 RTM_NEWNETCONF, 0, type);
530 	if (err < 0) {
531 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
532 		WARN_ON(err == -EMSGSIZE);
533 		kfree_skb(skb);
534 		goto errout;
535 	}
536 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_ATOMIC);
537 	return;
538 errout:
539 	rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
540 }
541 
542 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
543 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
544 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
545 };
546 
547 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
548 				     struct nlmsghdr *nlh)
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 static int inet6_netconf_dump_devconf(struct sk_buff *skb,
609 				      struct netlink_callback *cb)
610 {
611 	struct net *net = sock_net(skb->sk);
612 	int h, s_h;
613 	int idx, s_idx;
614 	struct net_device *dev;
615 	struct inet6_dev *idev;
616 	struct hlist_head *head;
617 
618 	s_h = cb->args[0];
619 	s_idx = idx = cb->args[1];
620 
621 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
622 		idx = 0;
623 		head = &net->dev_index_head[h];
624 		rcu_read_lock();
625 		cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^
626 			  net->dev_base_seq;
627 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
628 			if (idx < s_idx)
629 				goto cont;
630 			idev = __in6_dev_get(dev);
631 			if (!idev)
632 				goto cont;
633 
634 			if (inet6_netconf_fill_devconf(skb, dev->ifindex,
635 						       &idev->cnf,
636 						       NETLINK_CB(cb->skb).portid,
637 						       cb->nlh->nlmsg_seq,
638 						       RTM_NEWNETCONF,
639 						       NLM_F_MULTI,
640 						       -1) <= 0) {
641 				rcu_read_unlock();
642 				goto done;
643 			}
644 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
645 cont:
646 			idx++;
647 		}
648 		rcu_read_unlock();
649 	}
650 	if (h == NETDEV_HASHENTRIES) {
651 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
652 					       net->ipv6.devconf_all,
653 					       NETLINK_CB(cb->skb).portid,
654 					       cb->nlh->nlmsg_seq,
655 					       RTM_NEWNETCONF, NLM_F_MULTI,
656 					       -1) <= 0)
657 			goto done;
658 		else
659 			h++;
660 	}
661 	if (h == NETDEV_HASHENTRIES + 1) {
662 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
663 					       net->ipv6.devconf_dflt,
664 					       NETLINK_CB(cb->skb).portid,
665 					       cb->nlh->nlmsg_seq,
666 					       RTM_NEWNETCONF, NLM_F_MULTI,
667 					       -1) <= 0)
668 			goto done;
669 		else
670 			h++;
671 	}
672 done:
673 	cb->args[0] = h;
674 	cb->args[1] = idx;
675 
676 	return skb->len;
677 }
678 
679 #ifdef CONFIG_SYSCTL
680 static void dev_forward_change(struct inet6_dev *idev)
681 {
682 	struct net_device *dev;
683 	struct inet6_ifaddr *ifa;
684 
685 	if (!idev)
686 		return;
687 	dev = idev->dev;
688 	if (idev->cnf.forwarding)
689 		dev_disable_lro(dev);
690 	if (dev->flags & IFF_MULTICAST) {
691 		if (idev->cnf.forwarding) {
692 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
693 			ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
694 			ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters);
695 		} else {
696 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
697 			ipv6_dev_mc_dec(dev, &in6addr_interfacelocal_allrouters);
698 			ipv6_dev_mc_dec(dev, &in6addr_sitelocal_allrouters);
699 		}
700 	}
701 
702 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
703 		if (ifa->flags&IFA_F_TENTATIVE)
704 			continue;
705 		if (idev->cnf.forwarding)
706 			addrconf_join_anycast(ifa);
707 		else
708 			addrconf_leave_anycast(ifa);
709 	}
710 	inet6_netconf_notify_devconf(dev_net(dev), NETCONFA_FORWARDING,
711 				     dev->ifindex, &idev->cnf);
712 }
713 
714 
715 static void addrconf_forward_change(struct net *net, __s32 newf)
716 {
717 	struct net_device *dev;
718 	struct inet6_dev *idev;
719 
720 	for_each_netdev(net, dev) {
721 		idev = __in6_dev_get(dev);
722 		if (idev) {
723 			int changed = (!idev->cnf.forwarding) ^ (!newf);
724 			idev->cnf.forwarding = newf;
725 			if (changed)
726 				dev_forward_change(idev);
727 		}
728 	}
729 }
730 
731 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int newf)
732 {
733 	struct net *net;
734 	int old;
735 
736 	if (!rtnl_trylock())
737 		return restart_syscall();
738 
739 	net = (struct net *)table->extra2;
740 	old = *p;
741 	*p = newf;
742 
743 	if (p == &net->ipv6.devconf_dflt->forwarding) {
744 		if ((!newf) ^ (!old))
745 			inet6_netconf_notify_devconf(net, NETCONFA_FORWARDING,
746 						     NETCONFA_IFINDEX_DEFAULT,
747 						     net->ipv6.devconf_dflt);
748 		rtnl_unlock();
749 		return 0;
750 	}
751 
752 	if (p == &net->ipv6.devconf_all->forwarding) {
753 		net->ipv6.devconf_dflt->forwarding = newf;
754 		addrconf_forward_change(net, newf);
755 		if ((!newf) ^ (!old))
756 			inet6_netconf_notify_devconf(net, NETCONFA_FORWARDING,
757 						     NETCONFA_IFINDEX_ALL,
758 						     net->ipv6.devconf_all);
759 	} else if ((!newf) ^ (!old))
760 		dev_forward_change((struct inet6_dev *)table->extra1);
761 	rtnl_unlock();
762 
763 	if (newf)
764 		rt6_purge_dflt_routers(net);
765 	return 1;
766 }
767 #endif
768 
769 /* Nobody refers to this ifaddr, destroy it */
770 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
771 {
772 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
773 
774 #ifdef NET_REFCNT_DEBUG
775 	pr_debug("%s\n", __func__);
776 #endif
777 
778 	in6_dev_put(ifp->idev);
779 
780 	if (del_timer(&ifp->timer))
781 		pr_notice("Timer is still running, when freeing ifa=%p\n", ifp);
782 
783 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
784 		pr_warn("Freeing alive inet6 address %p\n", ifp);
785 		return;
786 	}
787 	ip6_rt_put(ifp->rt);
788 
789 	kfree_rcu(ifp, rcu);
790 }
791 
792 static void
793 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
794 {
795 	struct list_head *p;
796 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
797 
798 	/*
799 	 * Each device address list is sorted in order of scope -
800 	 * global before linklocal.
801 	 */
802 	list_for_each(p, &idev->addr_list) {
803 		struct inet6_ifaddr *ifa
804 			= list_entry(p, struct inet6_ifaddr, if_list);
805 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
806 			break;
807 	}
808 
809 	list_add_tail(&ifp->if_list, p);
810 }
811 
812 static u32 inet6_addr_hash(const struct in6_addr *addr)
813 {
814 	return hash_32(ipv6_addr_hash(addr), IN6_ADDR_HSIZE_SHIFT);
815 }
816 
817 /* On success it returns ifp with increased reference count */
818 
819 static struct inet6_ifaddr *
820 ipv6_add_addr(struct inet6_dev *idev, const struct in6_addr *addr, int pfxlen,
821 	      int scope, u32 flags)
822 {
823 	struct inet6_ifaddr *ifa = NULL;
824 	struct rt6_info *rt;
825 	unsigned int hash;
826 	int err = 0;
827 	int addr_type = ipv6_addr_type(addr);
828 
829 	if (addr_type == IPV6_ADDR_ANY ||
830 	    addr_type & IPV6_ADDR_MULTICAST ||
831 	    (!(idev->dev->flags & IFF_LOOPBACK) &&
832 	     addr_type & IPV6_ADDR_LOOPBACK))
833 		return ERR_PTR(-EADDRNOTAVAIL);
834 
835 	rcu_read_lock_bh();
836 	if (idev->dead) {
837 		err = -ENODEV;			/*XXX*/
838 		goto out2;
839 	}
840 
841 	if (idev->cnf.disable_ipv6) {
842 		err = -EACCES;
843 		goto out2;
844 	}
845 
846 	spin_lock(&addrconf_hash_lock);
847 
848 	/* Ignore adding duplicate addresses on an interface */
849 	if (ipv6_chk_same_addr(dev_net(idev->dev), addr, idev->dev)) {
850 		ADBG(("ipv6_add_addr: already assigned\n"));
851 		err = -EEXIST;
852 		goto out;
853 	}
854 
855 	ifa = kzalloc(sizeof(struct inet6_ifaddr), GFP_ATOMIC);
856 
857 	if (ifa == NULL) {
858 		ADBG(("ipv6_add_addr: malloc failed\n"));
859 		err = -ENOBUFS;
860 		goto out;
861 	}
862 
863 	rt = addrconf_dst_alloc(idev, addr, false);
864 	if (IS_ERR(rt)) {
865 		err = PTR_ERR(rt);
866 		goto out;
867 	}
868 
869 	ifa->addr = *addr;
870 
871 	spin_lock_init(&ifa->lock);
872 	spin_lock_init(&ifa->state_lock);
873 	init_timer(&ifa->timer);
874 	INIT_HLIST_NODE(&ifa->addr_lst);
875 	ifa->timer.data = (unsigned long) ifa;
876 	ifa->scope = scope;
877 	ifa->prefix_len = pfxlen;
878 	ifa->flags = flags | IFA_F_TENTATIVE;
879 	ifa->cstamp = ifa->tstamp = jiffies;
880 
881 	ifa->rt = rt;
882 
883 	ifa->idev = idev;
884 	in6_dev_hold(idev);
885 	/* For caller */
886 	in6_ifa_hold(ifa);
887 
888 	/* Add to big hash table */
889 	hash = inet6_addr_hash(addr);
890 
891 	hlist_add_head_rcu(&ifa->addr_lst, &inet6_addr_lst[hash]);
892 	spin_unlock(&addrconf_hash_lock);
893 
894 	write_lock(&idev->lock);
895 	/* Add to inet6_dev unicast addr list. */
896 	ipv6_link_dev_addr(idev, ifa);
897 
898 #ifdef CONFIG_IPV6_PRIVACY
899 	if (ifa->flags&IFA_F_TEMPORARY) {
900 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
901 		in6_ifa_hold(ifa);
902 	}
903 #endif
904 
905 	in6_ifa_hold(ifa);
906 	write_unlock(&idev->lock);
907 out2:
908 	rcu_read_unlock_bh();
909 
910 	if (likely(err == 0))
911 		atomic_notifier_call_chain(&inet6addr_chain, NETDEV_UP, ifa);
912 	else {
913 		kfree(ifa);
914 		ifa = ERR_PTR(err);
915 	}
916 
917 	return ifa;
918 out:
919 	spin_unlock(&addrconf_hash_lock);
920 	goto out2;
921 }
922 
923 /* This function wants to get referenced ifp and releases it before return */
924 
925 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
926 {
927 	struct inet6_ifaddr *ifa, *ifn;
928 	struct inet6_dev *idev = ifp->idev;
929 	int state;
930 	int deleted = 0, onlink = 0;
931 	unsigned long expires = jiffies;
932 
933 	spin_lock_bh(&ifp->state_lock);
934 	state = ifp->state;
935 	ifp->state = INET6_IFADDR_STATE_DEAD;
936 	spin_unlock_bh(&ifp->state_lock);
937 
938 	if (state == INET6_IFADDR_STATE_DEAD)
939 		goto out;
940 
941 	spin_lock_bh(&addrconf_hash_lock);
942 	hlist_del_init_rcu(&ifp->addr_lst);
943 	spin_unlock_bh(&addrconf_hash_lock);
944 
945 	write_lock_bh(&idev->lock);
946 #ifdef CONFIG_IPV6_PRIVACY
947 	if (ifp->flags&IFA_F_TEMPORARY) {
948 		list_del(&ifp->tmp_list);
949 		if (ifp->ifpub) {
950 			in6_ifa_put(ifp->ifpub);
951 			ifp->ifpub = NULL;
952 		}
953 		__in6_ifa_put(ifp);
954 	}
955 #endif
956 
957 	list_for_each_entry_safe(ifa, ifn, &idev->addr_list, if_list) {
958 		if (ifa == ifp) {
959 			list_del_init(&ifp->if_list);
960 			__in6_ifa_put(ifp);
961 
962 			if (!(ifp->flags & IFA_F_PERMANENT) || onlink > 0)
963 				break;
964 			deleted = 1;
965 			continue;
966 		} else if (ifp->flags & IFA_F_PERMANENT) {
967 			if (ipv6_prefix_equal(&ifa->addr, &ifp->addr,
968 					      ifp->prefix_len)) {
969 				if (ifa->flags & IFA_F_PERMANENT) {
970 					onlink = 1;
971 					if (deleted)
972 						break;
973 				} else {
974 					unsigned long lifetime;
975 
976 					if (!onlink)
977 						onlink = -1;
978 
979 					spin_lock(&ifa->lock);
980 
981 					lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
982 					/*
983 					 * Note: Because this address is
984 					 * not permanent, lifetime <
985 					 * LONG_MAX / HZ here.
986 					 */
987 					if (time_before(expires,
988 							ifa->tstamp + lifetime * HZ))
989 						expires = ifa->tstamp + lifetime * HZ;
990 					spin_unlock(&ifa->lock);
991 				}
992 			}
993 		}
994 	}
995 	write_unlock_bh(&idev->lock);
996 
997 	addrconf_del_timer(ifp);
998 
999 	ipv6_ifa_notify(RTM_DELADDR, ifp);
1000 
1001 	atomic_notifier_call_chain(&inet6addr_chain, NETDEV_DOWN, ifp);
1002 
1003 	/*
1004 	 * Purge or update corresponding prefix
1005 	 *
1006 	 * 1) we don't purge prefix here if address was not permanent.
1007 	 *    prefix is managed by its own lifetime.
1008 	 * 2) if there're no addresses, delete prefix.
1009 	 * 3) if there're still other permanent address(es),
1010 	 *    corresponding prefix is still permanent.
1011 	 * 4) otherwise, update prefix lifetime to the
1012 	 *    longest valid lifetime among the corresponding
1013 	 *    addresses on the device.
1014 	 *    Note: subsequent RA will update lifetime.
1015 	 *
1016 	 * --yoshfuji
1017 	 */
1018 	if ((ifp->flags & IFA_F_PERMANENT) && onlink < 1) {
1019 		struct in6_addr prefix;
1020 		struct rt6_info *rt;
1021 
1022 		ipv6_addr_prefix(&prefix, &ifp->addr, ifp->prefix_len);
1023 
1024 		rt = addrconf_get_prefix_route(&prefix,
1025 					       ifp->prefix_len,
1026 					       ifp->idev->dev,
1027 					       0, RTF_GATEWAY | RTF_DEFAULT);
1028 
1029 		if (rt) {
1030 			if (onlink == 0) {
1031 				ip6_del_rt(rt);
1032 				rt = NULL;
1033 			} else if (!(rt->rt6i_flags & RTF_EXPIRES)) {
1034 				rt6_set_expires(rt, expires);
1035 			}
1036 		}
1037 		ip6_rt_put(rt);
1038 	}
1039 
1040 	/* clean up prefsrc entries */
1041 	rt6_remove_prefsrc(ifp);
1042 out:
1043 	in6_ifa_put(ifp);
1044 }
1045 
1046 #ifdef CONFIG_IPV6_PRIVACY
1047 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp, struct inet6_ifaddr *ift)
1048 {
1049 	struct inet6_dev *idev = ifp->idev;
1050 	struct in6_addr addr, *tmpaddr;
1051 	unsigned long tmp_prefered_lft, tmp_valid_lft, tmp_tstamp, age;
1052 	unsigned long regen_advance;
1053 	int tmp_plen;
1054 	int ret = 0;
1055 	int max_addresses;
1056 	u32 addr_flags;
1057 	unsigned long now = jiffies;
1058 
1059 	write_lock(&idev->lock);
1060 	if (ift) {
1061 		spin_lock_bh(&ift->lock);
1062 		memcpy(&addr.s6_addr[8], &ift->addr.s6_addr[8], 8);
1063 		spin_unlock_bh(&ift->lock);
1064 		tmpaddr = &addr;
1065 	} else {
1066 		tmpaddr = NULL;
1067 	}
1068 retry:
1069 	in6_dev_hold(idev);
1070 	if (idev->cnf.use_tempaddr <= 0) {
1071 		write_unlock(&idev->lock);
1072 		pr_info("%s: use_tempaddr is disabled\n", __func__);
1073 		in6_dev_put(idev);
1074 		ret = -1;
1075 		goto out;
1076 	}
1077 	spin_lock_bh(&ifp->lock);
1078 	if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
1079 		idev->cnf.use_tempaddr = -1;	/*XXX*/
1080 		spin_unlock_bh(&ifp->lock);
1081 		write_unlock(&idev->lock);
1082 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1083 			__func__);
1084 		in6_dev_put(idev);
1085 		ret = -1;
1086 		goto out;
1087 	}
1088 	in6_ifa_hold(ifp);
1089 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1090 	__ipv6_try_regen_rndid(idev, tmpaddr);
1091 	memcpy(&addr.s6_addr[8], idev->rndid, 8);
1092 	age = (now - ifp->tstamp) / HZ;
1093 	tmp_valid_lft = min_t(__u32,
1094 			      ifp->valid_lft,
1095 			      idev->cnf.temp_valid_lft + age);
1096 	tmp_prefered_lft = min_t(__u32,
1097 				 ifp->prefered_lft,
1098 				 idev->cnf.temp_prefered_lft + age -
1099 				 idev->cnf.max_desync_factor);
1100 	tmp_plen = ifp->prefix_len;
1101 	max_addresses = idev->cnf.max_addresses;
1102 	tmp_tstamp = ifp->tstamp;
1103 	spin_unlock_bh(&ifp->lock);
1104 
1105 	regen_advance = idev->cnf.regen_max_retry *
1106 	                idev->cnf.dad_transmits *
1107 	                idev->nd_parms->retrans_time / HZ;
1108 	write_unlock(&idev->lock);
1109 
1110 	/* A temporary address is created only if this calculated Preferred
1111 	 * Lifetime is greater than REGEN_ADVANCE time units.  In particular,
1112 	 * an implementation must not create a temporary address with a zero
1113 	 * Preferred Lifetime.
1114 	 */
1115 	if (tmp_prefered_lft <= regen_advance) {
1116 		in6_ifa_put(ifp);
1117 		in6_dev_put(idev);
1118 		ret = -1;
1119 		goto out;
1120 	}
1121 
1122 	addr_flags = IFA_F_TEMPORARY;
1123 	/* set in addrconf_prefix_rcv() */
1124 	if (ifp->flags & IFA_F_OPTIMISTIC)
1125 		addr_flags |= IFA_F_OPTIMISTIC;
1126 
1127 	ift = !max_addresses ||
1128 	      ipv6_count_addresses(idev) < max_addresses ?
1129 		ipv6_add_addr(idev, &addr, tmp_plen,
1130 			      ipv6_addr_type(&addr)&IPV6_ADDR_SCOPE_MASK,
1131 			      addr_flags) : NULL;
1132 	if (IS_ERR_OR_NULL(ift)) {
1133 		in6_ifa_put(ifp);
1134 		in6_dev_put(idev);
1135 		pr_info("%s: retry temporary address regeneration\n", __func__);
1136 		tmpaddr = &addr;
1137 		write_lock(&idev->lock);
1138 		goto retry;
1139 	}
1140 
1141 	spin_lock_bh(&ift->lock);
1142 	ift->ifpub = ifp;
1143 	ift->valid_lft = tmp_valid_lft;
1144 	ift->prefered_lft = tmp_prefered_lft;
1145 	ift->cstamp = now;
1146 	ift->tstamp = tmp_tstamp;
1147 	spin_unlock_bh(&ift->lock);
1148 
1149 	addrconf_dad_start(ift);
1150 	in6_ifa_put(ift);
1151 	in6_dev_put(idev);
1152 out:
1153 	return ret;
1154 }
1155 #endif
1156 
1157 /*
1158  *	Choose an appropriate source address (RFC3484)
1159  */
1160 enum {
1161 	IPV6_SADDR_RULE_INIT = 0,
1162 	IPV6_SADDR_RULE_LOCAL,
1163 	IPV6_SADDR_RULE_SCOPE,
1164 	IPV6_SADDR_RULE_PREFERRED,
1165 #ifdef CONFIG_IPV6_MIP6
1166 	IPV6_SADDR_RULE_HOA,
1167 #endif
1168 	IPV6_SADDR_RULE_OIF,
1169 	IPV6_SADDR_RULE_LABEL,
1170 #ifdef CONFIG_IPV6_PRIVACY
1171 	IPV6_SADDR_RULE_PRIVACY,
1172 #endif
1173 	IPV6_SADDR_RULE_ORCHID,
1174 	IPV6_SADDR_RULE_PREFIX,
1175 	IPV6_SADDR_RULE_MAX
1176 };
1177 
1178 struct ipv6_saddr_score {
1179 	int			rule;
1180 	int			addr_type;
1181 	struct inet6_ifaddr	*ifa;
1182 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1183 	int			scopedist;
1184 	int			matchlen;
1185 };
1186 
1187 struct ipv6_saddr_dst {
1188 	const struct in6_addr *addr;
1189 	int ifindex;
1190 	int scope;
1191 	int label;
1192 	unsigned int prefs;
1193 };
1194 
1195 static inline int ipv6_saddr_preferred(int type)
1196 {
1197 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1198 		return 1;
1199 	return 0;
1200 }
1201 
1202 static int ipv6_get_saddr_eval(struct net *net,
1203 			       struct ipv6_saddr_score *score,
1204 			       struct ipv6_saddr_dst *dst,
1205 			       int i)
1206 {
1207 	int ret;
1208 
1209 	if (i <= score->rule) {
1210 		switch (i) {
1211 		case IPV6_SADDR_RULE_SCOPE:
1212 			ret = score->scopedist;
1213 			break;
1214 		case IPV6_SADDR_RULE_PREFIX:
1215 			ret = score->matchlen;
1216 			break;
1217 		default:
1218 			ret = !!test_bit(i, score->scorebits);
1219 		}
1220 		goto out;
1221 	}
1222 
1223 	switch (i) {
1224 	case IPV6_SADDR_RULE_INIT:
1225 		/* Rule 0: remember if hiscore is not ready yet */
1226 		ret = !!score->ifa;
1227 		break;
1228 	case IPV6_SADDR_RULE_LOCAL:
1229 		/* Rule 1: Prefer same address */
1230 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1231 		break;
1232 	case IPV6_SADDR_RULE_SCOPE:
1233 		/* Rule 2: Prefer appropriate scope
1234 		 *
1235 		 *      ret
1236 		 *       ^
1237 		 *    -1 |  d 15
1238 		 *    ---+--+-+---> scope
1239 		 *       |
1240 		 *       |             d is scope of the destination.
1241 		 *  B-d  |  \
1242 		 *       |   \      <- smaller scope is better if
1243 		 *  B-15 |    \        if scope is enough for destinaion.
1244 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1245 		 * d-C-1 | /
1246 		 *       |/         <- greater is better
1247 		 *   -C  /             if scope is not enough for destination.
1248 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1249 		 *
1250 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1251 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1252 		 * Assume B = 0 and we get C > 29.
1253 		 */
1254 		ret = __ipv6_addr_src_scope(score->addr_type);
1255 		if (ret >= dst->scope)
1256 			ret = -ret;
1257 		else
1258 			ret -= 128;	/* 30 is enough */
1259 		score->scopedist = ret;
1260 		break;
1261 	case IPV6_SADDR_RULE_PREFERRED:
1262 		/* Rule 3: Avoid deprecated and optimistic addresses */
1263 		ret = ipv6_saddr_preferred(score->addr_type) ||
1264 		      !(score->ifa->flags & (IFA_F_DEPRECATED|IFA_F_OPTIMISTIC));
1265 		break;
1266 #ifdef CONFIG_IPV6_MIP6
1267 	case IPV6_SADDR_RULE_HOA:
1268 	    {
1269 		/* Rule 4: Prefer home address */
1270 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1271 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1272 		break;
1273 	    }
1274 #endif
1275 	case IPV6_SADDR_RULE_OIF:
1276 		/* Rule 5: Prefer outgoing interface */
1277 		ret = (!dst->ifindex ||
1278 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1279 		break;
1280 	case IPV6_SADDR_RULE_LABEL:
1281 		/* Rule 6: Prefer matching label */
1282 		ret = ipv6_addr_label(net,
1283 				      &score->ifa->addr, score->addr_type,
1284 				      score->ifa->idev->dev->ifindex) == dst->label;
1285 		break;
1286 #ifdef CONFIG_IPV6_PRIVACY
1287 	case IPV6_SADDR_RULE_PRIVACY:
1288 	    {
1289 		/* Rule 7: Prefer public address
1290 		 * Note: prefer temporary address if use_tempaddr >= 2
1291 		 */
1292 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1293 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1294 				score->ifa->idev->cnf.use_tempaddr >= 2;
1295 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1296 		break;
1297 	    }
1298 #endif
1299 	case IPV6_SADDR_RULE_ORCHID:
1300 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1301 		 *	    non-ORCHID vs non-ORCHID
1302 		 */
1303 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1304 			ipv6_addr_orchid(dst->addr));
1305 		break;
1306 	case IPV6_SADDR_RULE_PREFIX:
1307 		/* Rule 8: Use longest matching prefix */
1308 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1309 		if (ret > score->ifa->prefix_len)
1310 			ret = score->ifa->prefix_len;
1311 		score->matchlen = ret;
1312 		break;
1313 	default:
1314 		ret = 0;
1315 	}
1316 
1317 	if (ret)
1318 		__set_bit(i, score->scorebits);
1319 	score->rule = i;
1320 out:
1321 	return ret;
1322 }
1323 
1324 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1325 		       const struct in6_addr *daddr, unsigned int prefs,
1326 		       struct in6_addr *saddr)
1327 {
1328 	struct ipv6_saddr_score scores[2],
1329 				*score = &scores[0], *hiscore = &scores[1];
1330 	struct ipv6_saddr_dst dst;
1331 	struct net_device *dev;
1332 	int dst_type;
1333 
1334 	dst_type = __ipv6_addr_type(daddr);
1335 	dst.addr = daddr;
1336 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1337 	dst.scope = __ipv6_addr_src_scope(dst_type);
1338 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1339 	dst.prefs = prefs;
1340 
1341 	hiscore->rule = -1;
1342 	hiscore->ifa = NULL;
1343 
1344 	rcu_read_lock();
1345 
1346 	for_each_netdev_rcu(net, dev) {
1347 		struct inet6_dev *idev;
1348 
1349 		/* Candidate Source Address (section 4)
1350 		 *  - multicast and link-local destination address,
1351 		 *    the set of candidate source address MUST only
1352 		 *    include addresses assigned to interfaces
1353 		 *    belonging to the same link as the outgoing
1354 		 *    interface.
1355 		 * (- For site-local destination addresses, the
1356 		 *    set of candidate source addresses MUST only
1357 		 *    include addresses assigned to interfaces
1358 		 *    belonging to the same site as the outgoing
1359 		 *    interface.)
1360 		 */
1361 		if (((dst_type & IPV6_ADDR_MULTICAST) ||
1362 		     dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL) &&
1363 		    dst.ifindex && dev->ifindex != dst.ifindex)
1364 			continue;
1365 
1366 		idev = __in6_dev_get(dev);
1367 		if (!idev)
1368 			continue;
1369 
1370 		read_lock_bh(&idev->lock);
1371 		list_for_each_entry(score->ifa, &idev->addr_list, if_list) {
1372 			int i;
1373 
1374 			/*
1375 			 * - Tentative Address (RFC2462 section 5.4)
1376 			 *  - A tentative address is not considered
1377 			 *    "assigned to an interface" in the traditional
1378 			 *    sense, unless it is also flagged as optimistic.
1379 			 * - Candidate Source Address (section 4)
1380 			 *  - In any case, anycast addresses, multicast
1381 			 *    addresses, and the unspecified address MUST
1382 			 *    NOT be included in a candidate set.
1383 			 */
1384 			if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1385 			    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1386 				continue;
1387 
1388 			score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1389 
1390 			if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1391 				     score->addr_type & IPV6_ADDR_MULTICAST)) {
1392 				LIMIT_NETDEBUG(KERN_DEBUG
1393 					       "ADDRCONF: unspecified / multicast address "
1394 					       "assigned as unicast address on %s",
1395 					       dev->name);
1396 				continue;
1397 			}
1398 
1399 			score->rule = -1;
1400 			bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1401 
1402 			for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1403 				int minihiscore, miniscore;
1404 
1405 				minihiscore = ipv6_get_saddr_eval(net, hiscore, &dst, i);
1406 				miniscore = ipv6_get_saddr_eval(net, score, &dst, i);
1407 
1408 				if (minihiscore > miniscore) {
1409 					if (i == IPV6_SADDR_RULE_SCOPE &&
1410 					    score->scopedist > 0) {
1411 						/*
1412 						 * special case:
1413 						 * each remaining entry
1414 						 * has too small (not enough)
1415 						 * scope, because ifa entries
1416 						 * are sorted by their scope
1417 						 * values.
1418 						 */
1419 						goto try_nextdev;
1420 					}
1421 					break;
1422 				} else if (minihiscore < miniscore) {
1423 					if (hiscore->ifa)
1424 						in6_ifa_put(hiscore->ifa);
1425 
1426 					in6_ifa_hold(score->ifa);
1427 
1428 					swap(hiscore, score);
1429 
1430 					/* restore our iterator */
1431 					score->ifa = hiscore->ifa;
1432 
1433 					break;
1434 				}
1435 			}
1436 		}
1437 try_nextdev:
1438 		read_unlock_bh(&idev->lock);
1439 	}
1440 	rcu_read_unlock();
1441 
1442 	if (!hiscore->ifa)
1443 		return -EADDRNOTAVAIL;
1444 
1445 	*saddr = hiscore->ifa->addr;
1446 	in6_ifa_put(hiscore->ifa);
1447 	return 0;
1448 }
1449 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1450 
1451 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1452 		    unsigned char banned_flags)
1453 {
1454 	struct inet6_dev *idev;
1455 	int err = -EADDRNOTAVAIL;
1456 
1457 	rcu_read_lock();
1458 	idev = __in6_dev_get(dev);
1459 	if (idev) {
1460 		struct inet6_ifaddr *ifp;
1461 
1462 		read_lock_bh(&idev->lock);
1463 		list_for_each_entry(ifp, &idev->addr_list, if_list) {
1464 			if (ifp->scope == IFA_LINK &&
1465 			    !(ifp->flags & banned_flags)) {
1466 				*addr = ifp->addr;
1467 				err = 0;
1468 				break;
1469 			}
1470 		}
1471 		read_unlock_bh(&idev->lock);
1472 	}
1473 	rcu_read_unlock();
1474 	return err;
1475 }
1476 
1477 static int ipv6_count_addresses(struct inet6_dev *idev)
1478 {
1479 	int cnt = 0;
1480 	struct inet6_ifaddr *ifp;
1481 
1482 	read_lock_bh(&idev->lock);
1483 	list_for_each_entry(ifp, &idev->addr_list, if_list)
1484 		cnt++;
1485 	read_unlock_bh(&idev->lock);
1486 	return cnt;
1487 }
1488 
1489 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1490 		  struct net_device *dev, int strict)
1491 {
1492 	struct inet6_ifaddr *ifp;
1493 	unsigned int hash = inet6_addr_hash(addr);
1494 
1495 	rcu_read_lock_bh();
1496 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
1497 		if (!net_eq(dev_net(ifp->idev->dev), net))
1498 			continue;
1499 		if (ipv6_addr_equal(&ifp->addr, addr) &&
1500 		    !(ifp->flags&IFA_F_TENTATIVE) &&
1501 		    (dev == NULL || ifp->idev->dev == dev ||
1502 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1503 			rcu_read_unlock_bh();
1504 			return 1;
1505 		}
1506 	}
1507 
1508 	rcu_read_unlock_bh();
1509 	return 0;
1510 }
1511 EXPORT_SYMBOL(ipv6_chk_addr);
1512 
1513 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
1514 			       struct net_device *dev)
1515 {
1516 	unsigned int hash = inet6_addr_hash(addr);
1517 	struct inet6_ifaddr *ifp;
1518 
1519 	hlist_for_each_entry(ifp, &inet6_addr_lst[hash], addr_lst) {
1520 		if (!net_eq(dev_net(ifp->idev->dev), net))
1521 			continue;
1522 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1523 			if (dev == NULL || ifp->idev->dev == dev)
1524 				return true;
1525 		}
1526 	}
1527 	return false;
1528 }
1529 
1530 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
1531 {
1532 	struct inet6_dev *idev;
1533 	struct inet6_ifaddr *ifa;
1534 	int	onlink;
1535 
1536 	onlink = 0;
1537 	rcu_read_lock();
1538 	idev = __in6_dev_get(dev);
1539 	if (idev) {
1540 		read_lock_bh(&idev->lock);
1541 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
1542 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
1543 						   ifa->prefix_len);
1544 			if (onlink)
1545 				break;
1546 		}
1547 		read_unlock_bh(&idev->lock);
1548 	}
1549 	rcu_read_unlock();
1550 	return onlink;
1551 }
1552 EXPORT_SYMBOL(ipv6_chk_prefix);
1553 
1554 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
1555 				     struct net_device *dev, int strict)
1556 {
1557 	struct inet6_ifaddr *ifp, *result = NULL;
1558 	unsigned int hash = inet6_addr_hash(addr);
1559 
1560 	rcu_read_lock_bh();
1561 	hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[hash], addr_lst) {
1562 		if (!net_eq(dev_net(ifp->idev->dev), net))
1563 			continue;
1564 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1565 			if (dev == NULL || ifp->idev->dev == dev ||
1566 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
1567 				result = ifp;
1568 				in6_ifa_hold(ifp);
1569 				break;
1570 			}
1571 		}
1572 	}
1573 	rcu_read_unlock_bh();
1574 
1575 	return result;
1576 }
1577 
1578 /* Gets referenced address, destroys ifaddr */
1579 
1580 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
1581 {
1582 	if (ifp->flags&IFA_F_PERMANENT) {
1583 		spin_lock_bh(&ifp->lock);
1584 		addrconf_del_timer(ifp);
1585 		ifp->flags |= IFA_F_TENTATIVE;
1586 		if (dad_failed)
1587 			ifp->flags |= IFA_F_DADFAILED;
1588 		spin_unlock_bh(&ifp->lock);
1589 		if (dad_failed)
1590 			ipv6_ifa_notify(0, ifp);
1591 		in6_ifa_put(ifp);
1592 #ifdef CONFIG_IPV6_PRIVACY
1593 	} else if (ifp->flags&IFA_F_TEMPORARY) {
1594 		struct inet6_ifaddr *ifpub;
1595 		spin_lock_bh(&ifp->lock);
1596 		ifpub = ifp->ifpub;
1597 		if (ifpub) {
1598 			in6_ifa_hold(ifpub);
1599 			spin_unlock_bh(&ifp->lock);
1600 			ipv6_create_tempaddr(ifpub, ifp);
1601 			in6_ifa_put(ifpub);
1602 		} else {
1603 			spin_unlock_bh(&ifp->lock);
1604 		}
1605 		ipv6_del_addr(ifp);
1606 #endif
1607 	} else
1608 		ipv6_del_addr(ifp);
1609 }
1610 
1611 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
1612 {
1613 	int err = -ENOENT;
1614 
1615 	spin_lock(&ifp->state_lock);
1616 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
1617 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
1618 		err = 0;
1619 	}
1620 	spin_unlock(&ifp->state_lock);
1621 
1622 	return err;
1623 }
1624 
1625 void addrconf_dad_failure(struct inet6_ifaddr *ifp)
1626 {
1627 	struct inet6_dev *idev = ifp->idev;
1628 
1629 	if (addrconf_dad_end(ifp)) {
1630 		in6_ifa_put(ifp);
1631 		return;
1632 	}
1633 
1634 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c detected!\n",
1635 			     ifp->idev->dev->name, &ifp->addr);
1636 
1637 	if (idev->cnf.accept_dad > 1 && !idev->cnf.disable_ipv6) {
1638 		struct in6_addr addr;
1639 
1640 		addr.s6_addr32[0] = htonl(0xfe800000);
1641 		addr.s6_addr32[1] = 0;
1642 
1643 		if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
1644 		    ipv6_addr_equal(&ifp->addr, &addr)) {
1645 			/* DAD failed for link-local based on MAC address */
1646 			idev->cnf.disable_ipv6 = 1;
1647 
1648 			pr_info("%s: IPv6 being disabled!\n",
1649 				ifp->idev->dev->name);
1650 		}
1651 	}
1652 
1653 	addrconf_dad_stop(ifp, 1);
1654 }
1655 
1656 /* Join to solicited addr multicast group. */
1657 
1658 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
1659 {
1660 	struct in6_addr maddr;
1661 
1662 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
1663 		return;
1664 
1665 	addrconf_addr_solict_mult(addr, &maddr);
1666 	ipv6_dev_mc_inc(dev, &maddr);
1667 }
1668 
1669 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
1670 {
1671 	struct in6_addr maddr;
1672 
1673 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
1674 		return;
1675 
1676 	addrconf_addr_solict_mult(addr, &maddr);
1677 	__ipv6_dev_mc_dec(idev, &maddr);
1678 }
1679 
1680 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
1681 {
1682 	struct in6_addr addr;
1683 	if (ifp->prefix_len == 127) /* RFC 6164 */
1684 		return;
1685 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
1686 	if (ipv6_addr_any(&addr))
1687 		return;
1688 	ipv6_dev_ac_inc(ifp->idev->dev, &addr);
1689 }
1690 
1691 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
1692 {
1693 	struct in6_addr addr;
1694 	if (ifp->prefix_len == 127) /* RFC 6164 */
1695 		return;
1696 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
1697 	if (ipv6_addr_any(&addr))
1698 		return;
1699 	__ipv6_dev_ac_dec(ifp->idev, &addr);
1700 }
1701 
1702 static int addrconf_ifid_eui48(u8 *eui, struct net_device *dev)
1703 {
1704 	if (dev->addr_len != ETH_ALEN)
1705 		return -1;
1706 	memcpy(eui, dev->dev_addr, 3);
1707 	memcpy(eui + 5, dev->dev_addr + 3, 3);
1708 
1709 	/*
1710 	 * The zSeries OSA network cards can be shared among various
1711 	 * OS instances, but the OSA cards have only one MAC address.
1712 	 * This leads to duplicate address conflicts in conjunction
1713 	 * with IPv6 if more than one instance uses the same card.
1714 	 *
1715 	 * The driver for these cards can deliver a unique 16-bit
1716 	 * identifier for each instance sharing the same card.  It is
1717 	 * placed instead of 0xFFFE in the interface identifier.  The
1718 	 * "u" bit of the interface identifier is not inverted in this
1719 	 * case.  Hence the resulting interface identifier has local
1720 	 * scope according to RFC2373.
1721 	 */
1722 	if (dev->dev_id) {
1723 		eui[3] = (dev->dev_id >> 8) & 0xFF;
1724 		eui[4] = dev->dev_id & 0xFF;
1725 	} else {
1726 		eui[3] = 0xFF;
1727 		eui[4] = 0xFE;
1728 		eui[0] ^= 2;
1729 	}
1730 	return 0;
1731 }
1732 
1733 static int addrconf_ifid_eui64(u8 *eui, struct net_device *dev)
1734 {
1735 	if (dev->addr_len != IEEE802154_ADDR_LEN)
1736 		return -1;
1737 	memcpy(eui, dev->dev_addr, 8);
1738 	eui[0] ^= 2;
1739 	return 0;
1740 }
1741 
1742 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
1743 {
1744 	union fwnet_hwaddr *ha;
1745 
1746 	if (dev->addr_len != FWNET_ALEN)
1747 		return -1;
1748 
1749 	ha = (union fwnet_hwaddr *)dev->dev_addr;
1750 
1751 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
1752 	eui[0] ^= 2;
1753 	return 0;
1754 }
1755 
1756 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
1757 {
1758 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
1759 	if (dev->addr_len != ARCNET_ALEN)
1760 		return -1;
1761 	memset(eui, 0, 7);
1762 	eui[7] = *(u8 *)dev->dev_addr;
1763 	return 0;
1764 }
1765 
1766 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
1767 {
1768 	if (dev->addr_len != INFINIBAND_ALEN)
1769 		return -1;
1770 	memcpy(eui, dev->dev_addr + 12, 8);
1771 	eui[0] |= 2;
1772 	return 0;
1773 }
1774 
1775 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
1776 {
1777 	if (addr == 0)
1778 		return -1;
1779 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
1780 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
1781 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
1782 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
1783 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
1784 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
1785 	eui[1] = 0;
1786 	eui[2] = 0x5E;
1787 	eui[3] = 0xFE;
1788 	memcpy(eui + 4, &addr, 4);
1789 	return 0;
1790 }
1791 
1792 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
1793 {
1794 	if (dev->priv_flags & IFF_ISATAP)
1795 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
1796 	return -1;
1797 }
1798 
1799 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
1800 {
1801 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
1802 }
1803 
1804 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
1805 {
1806 	switch (dev->type) {
1807 	case ARPHRD_ETHER:
1808 	case ARPHRD_FDDI:
1809 		return addrconf_ifid_eui48(eui, dev);
1810 	case ARPHRD_ARCNET:
1811 		return addrconf_ifid_arcnet(eui, dev);
1812 	case ARPHRD_INFINIBAND:
1813 		return addrconf_ifid_infiniband(eui, dev);
1814 	case ARPHRD_SIT:
1815 		return addrconf_ifid_sit(eui, dev);
1816 	case ARPHRD_IPGRE:
1817 		return addrconf_ifid_gre(eui, dev);
1818 	case ARPHRD_IEEE802154:
1819 		return addrconf_ifid_eui64(eui, dev);
1820 	case ARPHRD_IEEE1394:
1821 		return addrconf_ifid_ieee1394(eui, dev);
1822 	}
1823 	return -1;
1824 }
1825 
1826 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
1827 {
1828 	int err = -1;
1829 	struct inet6_ifaddr *ifp;
1830 
1831 	read_lock_bh(&idev->lock);
1832 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
1833 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
1834 			memcpy(eui, ifp->addr.s6_addr+8, 8);
1835 			err = 0;
1836 			break;
1837 		}
1838 	}
1839 	read_unlock_bh(&idev->lock);
1840 	return err;
1841 }
1842 
1843 #ifdef CONFIG_IPV6_PRIVACY
1844 /* (re)generation of randomized interface identifier (RFC 3041 3.2, 3.5) */
1845 static void __ipv6_regen_rndid(struct inet6_dev *idev)
1846 {
1847 regen:
1848 	get_random_bytes(idev->rndid, sizeof(idev->rndid));
1849 	idev->rndid[0] &= ~0x02;
1850 
1851 	/*
1852 	 * <draft-ietf-ipngwg-temp-addresses-v2-00.txt>:
1853 	 * check if generated address is not inappropriate
1854 	 *
1855 	 *  - Reserved subnet anycast (RFC 2526)
1856 	 *	11111101 11....11 1xxxxxxx
1857 	 *  - ISATAP (RFC4214) 6.1
1858 	 *	00-00-5E-FE-xx-xx-xx-xx
1859 	 *  - value 0
1860 	 *  - XXX: already assigned to an address on the device
1861 	 */
1862 	if (idev->rndid[0] == 0xfd &&
1863 	    (idev->rndid[1]&idev->rndid[2]&idev->rndid[3]&idev->rndid[4]&idev->rndid[5]&idev->rndid[6]) == 0xff &&
1864 	    (idev->rndid[7]&0x80))
1865 		goto regen;
1866 	if ((idev->rndid[0]|idev->rndid[1]) == 0) {
1867 		if (idev->rndid[2] == 0x5e && idev->rndid[3] == 0xfe)
1868 			goto regen;
1869 		if ((idev->rndid[2]|idev->rndid[3]|idev->rndid[4]|idev->rndid[5]|idev->rndid[6]|idev->rndid[7]) == 0x00)
1870 			goto regen;
1871 	}
1872 }
1873 
1874 static void ipv6_regen_rndid(unsigned long data)
1875 {
1876 	struct inet6_dev *idev = (struct inet6_dev *) data;
1877 	unsigned long expires;
1878 
1879 	rcu_read_lock_bh();
1880 	write_lock_bh(&idev->lock);
1881 
1882 	if (idev->dead)
1883 		goto out;
1884 
1885 	__ipv6_regen_rndid(idev);
1886 
1887 	expires = jiffies +
1888 		idev->cnf.temp_prefered_lft * HZ -
1889 		idev->cnf.regen_max_retry * idev->cnf.dad_transmits * idev->nd_parms->retrans_time -
1890 		idev->cnf.max_desync_factor * HZ;
1891 	if (time_before(expires, jiffies)) {
1892 		pr_warn("%s: too short regeneration interval; timer disabled for %s\n",
1893 			__func__, idev->dev->name);
1894 		goto out;
1895 	}
1896 
1897 	if (!mod_timer(&idev->regen_timer, expires))
1898 		in6_dev_hold(idev);
1899 
1900 out:
1901 	write_unlock_bh(&idev->lock);
1902 	rcu_read_unlock_bh();
1903 	in6_dev_put(idev);
1904 }
1905 
1906 static void  __ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr)
1907 {
1908 	if (tmpaddr && memcmp(idev->rndid, &tmpaddr->s6_addr[8], 8) == 0)
1909 		__ipv6_regen_rndid(idev);
1910 }
1911 #endif
1912 
1913 /*
1914  *	Add prefix route.
1915  */
1916 
1917 static void
1918 addrconf_prefix_route(struct in6_addr *pfx, int plen, struct net_device *dev,
1919 		      unsigned long expires, u32 flags)
1920 {
1921 	struct fib6_config cfg = {
1922 		.fc_table = RT6_TABLE_PREFIX,
1923 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
1924 		.fc_ifindex = dev->ifindex,
1925 		.fc_expires = expires,
1926 		.fc_dst_len = plen,
1927 		.fc_flags = RTF_UP | flags,
1928 		.fc_nlinfo.nl_net = dev_net(dev),
1929 		.fc_protocol = RTPROT_KERNEL,
1930 	};
1931 
1932 	cfg.fc_dst = *pfx;
1933 
1934 	/* Prevent useless cloning on PtP SIT.
1935 	   This thing is done here expecting that the whole
1936 	   class of non-broadcast devices need not cloning.
1937 	 */
1938 #if IS_ENABLED(CONFIG_IPV6_SIT)
1939 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
1940 		cfg.fc_flags |= RTF_NONEXTHOP;
1941 #endif
1942 
1943 	ip6_route_add(&cfg);
1944 }
1945 
1946 
1947 static struct rt6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
1948 						  int plen,
1949 						  const struct net_device *dev,
1950 						  u32 flags, u32 noflags)
1951 {
1952 	struct fib6_node *fn;
1953 	struct rt6_info *rt = NULL;
1954 	struct fib6_table *table;
1955 
1956 	table = fib6_get_table(dev_net(dev), RT6_TABLE_PREFIX);
1957 	if (table == NULL)
1958 		return NULL;
1959 
1960 	read_lock_bh(&table->tb6_lock);
1961 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0);
1962 	if (!fn)
1963 		goto out;
1964 	for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
1965 		if (rt->dst.dev->ifindex != dev->ifindex)
1966 			continue;
1967 		if ((rt->rt6i_flags & flags) != flags)
1968 			continue;
1969 		if ((rt->rt6i_flags & noflags) != 0)
1970 			continue;
1971 		dst_hold(&rt->dst);
1972 		break;
1973 	}
1974 out:
1975 	read_unlock_bh(&table->tb6_lock);
1976 	return rt;
1977 }
1978 
1979 
1980 /* Create "default" multicast route to the interface */
1981 
1982 static void addrconf_add_mroute(struct net_device *dev)
1983 {
1984 	struct fib6_config cfg = {
1985 		.fc_table = RT6_TABLE_LOCAL,
1986 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
1987 		.fc_ifindex = dev->ifindex,
1988 		.fc_dst_len = 8,
1989 		.fc_flags = RTF_UP,
1990 		.fc_nlinfo.nl_net = dev_net(dev),
1991 	};
1992 
1993 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
1994 
1995 	ip6_route_add(&cfg);
1996 }
1997 
1998 #if IS_ENABLED(CONFIG_IPV6_SIT)
1999 static void sit_route_add(struct net_device *dev)
2000 {
2001 	struct fib6_config cfg = {
2002 		.fc_table = RT6_TABLE_MAIN,
2003 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2004 		.fc_ifindex = dev->ifindex,
2005 		.fc_dst_len = 96,
2006 		.fc_flags = RTF_UP | RTF_NONEXTHOP,
2007 		.fc_nlinfo.nl_net = dev_net(dev),
2008 	};
2009 
2010 	/* prefix length - 96 bits "::d.d.d.d" */
2011 	ip6_route_add(&cfg);
2012 }
2013 #endif
2014 
2015 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2016 {
2017 	struct inet6_dev *idev;
2018 
2019 	ASSERT_RTNL();
2020 
2021 	idev = ipv6_find_idev(dev);
2022 	if (!idev)
2023 		return ERR_PTR(-ENOBUFS);
2024 
2025 	if (idev->cnf.disable_ipv6)
2026 		return ERR_PTR(-EACCES);
2027 
2028 	/* Add default multicast route */
2029 	if (!(dev->flags & IFF_LOOPBACK))
2030 		addrconf_add_mroute(dev);
2031 
2032 	return idev;
2033 }
2034 
2035 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2036 {
2037 	struct prefix_info *pinfo;
2038 	__u32 valid_lft;
2039 	__u32 prefered_lft;
2040 	int addr_type;
2041 	struct inet6_dev *in6_dev;
2042 	struct net *net = dev_net(dev);
2043 
2044 	pinfo = (struct prefix_info *) opt;
2045 
2046 	if (len < sizeof(struct prefix_info)) {
2047 		ADBG(("addrconf: prefix option too short\n"));
2048 		return;
2049 	}
2050 
2051 	/*
2052 	 *	Validation checks ([ADDRCONF], page 19)
2053 	 */
2054 
2055 	addr_type = ipv6_addr_type(&pinfo->prefix);
2056 
2057 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2058 		return;
2059 
2060 	valid_lft = ntohl(pinfo->valid);
2061 	prefered_lft = ntohl(pinfo->prefered);
2062 
2063 	if (prefered_lft > valid_lft) {
2064 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2065 		return;
2066 	}
2067 
2068 	in6_dev = in6_dev_get(dev);
2069 
2070 	if (in6_dev == NULL) {
2071 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2072 				    dev->name);
2073 		return;
2074 	}
2075 
2076 	/*
2077 	 *	Two things going on here:
2078 	 *	1) Add routes for on-link prefixes
2079 	 *	2) Configure prefixes with the auto flag set
2080 	 */
2081 
2082 	if (pinfo->onlink) {
2083 		struct rt6_info *rt;
2084 		unsigned long rt_expires;
2085 
2086 		/* Avoid arithmetic overflow. Really, we could
2087 		 * save rt_expires in seconds, likely valid_lft,
2088 		 * but it would require division in fib gc, that it
2089 		 * not good.
2090 		 */
2091 		if (HZ > USER_HZ)
2092 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2093 		else
2094 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2095 
2096 		if (addrconf_finite_timeout(rt_expires))
2097 			rt_expires *= HZ;
2098 
2099 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2100 					       pinfo->prefix_len,
2101 					       dev,
2102 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2103 					       RTF_GATEWAY | RTF_DEFAULT);
2104 
2105 		if (rt) {
2106 			/* Autoconf prefix route */
2107 			if (valid_lft == 0) {
2108 				ip6_del_rt(rt);
2109 				rt = NULL;
2110 			} else if (addrconf_finite_timeout(rt_expires)) {
2111 				/* not infinity */
2112 				rt6_set_expires(rt, jiffies + rt_expires);
2113 			} else {
2114 				rt6_clean_expires(rt);
2115 			}
2116 		} else if (valid_lft) {
2117 			clock_t expires = 0;
2118 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2119 			if (addrconf_finite_timeout(rt_expires)) {
2120 				/* not infinity */
2121 				flags |= RTF_EXPIRES;
2122 				expires = jiffies_to_clock_t(rt_expires);
2123 			}
2124 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2125 					      dev, expires, flags);
2126 		}
2127 		ip6_rt_put(rt);
2128 	}
2129 
2130 	/* Try to figure out our local address for this prefix */
2131 
2132 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
2133 		struct inet6_ifaddr *ifp;
2134 		struct in6_addr addr;
2135 		int create = 0, update_lft = 0;
2136 
2137 		if (pinfo->prefix_len == 64) {
2138 			memcpy(&addr, &pinfo->prefix, 8);
2139 			if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2140 			    ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2141 				in6_dev_put(in6_dev);
2142 				return;
2143 			}
2144 			goto ok;
2145 		}
2146 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2147 				    pinfo->prefix_len);
2148 		in6_dev_put(in6_dev);
2149 		return;
2150 
2151 ok:
2152 
2153 		ifp = ipv6_get_ifaddr(net, &addr, dev, 1);
2154 
2155 		if (ifp == NULL && valid_lft) {
2156 			int max_addresses = in6_dev->cnf.max_addresses;
2157 			u32 addr_flags = 0;
2158 
2159 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2160 			if (in6_dev->cnf.optimistic_dad &&
2161 			    !net->ipv6.devconf_all->forwarding && sllao)
2162 				addr_flags = IFA_F_OPTIMISTIC;
2163 #endif
2164 
2165 			/* Do not allow to create too much of autoconfigured
2166 			 * addresses; this would be too easy way to crash kernel.
2167 			 */
2168 			if (!max_addresses ||
2169 			    ipv6_count_addresses(in6_dev) < max_addresses)
2170 				ifp = ipv6_add_addr(in6_dev, &addr, pinfo->prefix_len,
2171 						    addr_type&IPV6_ADDR_SCOPE_MASK,
2172 						    addr_flags);
2173 
2174 			if (IS_ERR_OR_NULL(ifp)) {
2175 				in6_dev_put(in6_dev);
2176 				return;
2177 			}
2178 
2179 			update_lft = create = 1;
2180 			ifp->cstamp = jiffies;
2181 			addrconf_dad_start(ifp);
2182 		}
2183 
2184 		if (ifp) {
2185 			int flags;
2186 			unsigned long now;
2187 #ifdef CONFIG_IPV6_PRIVACY
2188 			struct inet6_ifaddr *ift;
2189 #endif
2190 			u32 stored_lft;
2191 
2192 			/* update lifetime (RFC2462 5.5.3 e) */
2193 			spin_lock(&ifp->lock);
2194 			now = jiffies;
2195 			if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2196 				stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2197 			else
2198 				stored_lft = 0;
2199 			if (!update_lft && stored_lft) {
2200 				if (valid_lft > MIN_VALID_LIFETIME ||
2201 				    valid_lft > stored_lft)
2202 					update_lft = 1;
2203 				else if (stored_lft <= MIN_VALID_LIFETIME) {
2204 					/* valid_lft <= stored_lft is always true */
2205 					/*
2206 					 * RFC 4862 Section 5.5.3e:
2207 					 * "Note that the preferred lifetime of
2208 					 *  the corresponding address is always
2209 					 *  reset to the Preferred Lifetime in
2210 					 *  the received Prefix Information
2211 					 *  option, regardless of whether the
2212 					 *  valid lifetime is also reset or
2213 					 *  ignored."
2214 					 *
2215 					 *  So if the preferred lifetime in
2216 					 *  this advertisement is different
2217 					 *  than what we have stored, but the
2218 					 *  valid lifetime is invalid, just
2219 					 *  reset prefered_lft.
2220 					 *
2221 					 *  We must set the valid lifetime
2222 					 *  to the stored lifetime since we'll
2223 					 *  be updating the timestamp below,
2224 					 *  else we'll set it back to the
2225 					 *  minimum.
2226 					 */
2227 					if (prefered_lft != ifp->prefered_lft) {
2228 						valid_lft = stored_lft;
2229 						update_lft = 1;
2230 					}
2231 				} else {
2232 					valid_lft = MIN_VALID_LIFETIME;
2233 					if (valid_lft < prefered_lft)
2234 						prefered_lft = valid_lft;
2235 					update_lft = 1;
2236 				}
2237 			}
2238 
2239 			if (update_lft) {
2240 				ifp->valid_lft = valid_lft;
2241 				ifp->prefered_lft = prefered_lft;
2242 				ifp->tstamp = now;
2243 				flags = ifp->flags;
2244 				ifp->flags &= ~IFA_F_DEPRECATED;
2245 				spin_unlock(&ifp->lock);
2246 
2247 				if (!(flags&IFA_F_TENTATIVE))
2248 					ipv6_ifa_notify(0, ifp);
2249 			} else
2250 				spin_unlock(&ifp->lock);
2251 
2252 #ifdef CONFIG_IPV6_PRIVACY
2253 			read_lock_bh(&in6_dev->lock);
2254 			/* update all temporary addresses in the list */
2255 			list_for_each_entry(ift, &in6_dev->tempaddr_list,
2256 					    tmp_list) {
2257 				int age, max_valid, max_prefered;
2258 
2259 				if (ifp != ift->ifpub)
2260 					continue;
2261 
2262 				/*
2263 				 * RFC 4941 section 3.3:
2264 				 * If a received option will extend the lifetime
2265 				 * of a public address, the lifetimes of
2266 				 * temporary addresses should be extended,
2267 				 * subject to the overall constraint that no
2268 				 * temporary addresses should ever remain
2269 				 * "valid" or "preferred" for a time longer than
2270 				 * (TEMP_VALID_LIFETIME) or
2271 				 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR),
2272 				 * respectively.
2273 				 */
2274 				age = (now - ift->cstamp) / HZ;
2275 				max_valid = in6_dev->cnf.temp_valid_lft - age;
2276 				if (max_valid < 0)
2277 					max_valid = 0;
2278 
2279 				max_prefered = in6_dev->cnf.temp_prefered_lft -
2280 					       in6_dev->cnf.max_desync_factor -
2281 					       age;
2282 				if (max_prefered < 0)
2283 					max_prefered = 0;
2284 
2285 				if (valid_lft > max_valid)
2286 					valid_lft = max_valid;
2287 
2288 				if (prefered_lft > max_prefered)
2289 					prefered_lft = max_prefered;
2290 
2291 				spin_lock(&ift->lock);
2292 				flags = ift->flags;
2293 				ift->valid_lft = valid_lft;
2294 				ift->prefered_lft = prefered_lft;
2295 				ift->tstamp = now;
2296 				if (prefered_lft > 0)
2297 					ift->flags &= ~IFA_F_DEPRECATED;
2298 
2299 				spin_unlock(&ift->lock);
2300 				if (!(flags&IFA_F_TENTATIVE))
2301 					ipv6_ifa_notify(0, ift);
2302 			}
2303 
2304 			if ((create || list_empty(&in6_dev->tempaddr_list)) && in6_dev->cnf.use_tempaddr > 0) {
2305 				/*
2306 				 * When a new public address is created as
2307 				 * described in [ADDRCONF], also create a new
2308 				 * temporary address. Also create a temporary
2309 				 * address if it's enabled but no temporary
2310 				 * address currently exists.
2311 				 */
2312 				read_unlock_bh(&in6_dev->lock);
2313 				ipv6_create_tempaddr(ifp, NULL);
2314 			} else {
2315 				read_unlock_bh(&in6_dev->lock);
2316 			}
2317 #endif
2318 			in6_ifa_put(ifp);
2319 			addrconf_verify(0);
2320 		}
2321 	}
2322 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2323 	in6_dev_put(in6_dev);
2324 }
2325 
2326 /*
2327  *	Set destination address.
2328  *	Special case for SIT interfaces where we create a new "virtual"
2329  *	device.
2330  */
2331 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2332 {
2333 	struct in6_ifreq ireq;
2334 	struct net_device *dev;
2335 	int err = -EINVAL;
2336 
2337 	rtnl_lock();
2338 
2339 	err = -EFAULT;
2340 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2341 		goto err_exit;
2342 
2343 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2344 
2345 	err = -ENODEV;
2346 	if (dev == NULL)
2347 		goto err_exit;
2348 
2349 #if IS_ENABLED(CONFIG_IPV6_SIT)
2350 	if (dev->type == ARPHRD_SIT) {
2351 		const struct net_device_ops *ops = dev->netdev_ops;
2352 		struct ifreq ifr;
2353 		struct ip_tunnel_parm p;
2354 
2355 		err = -EADDRNOTAVAIL;
2356 		if (!(ipv6_addr_type(&ireq.ifr6_addr) & IPV6_ADDR_COMPATv4))
2357 			goto err_exit;
2358 
2359 		memset(&p, 0, sizeof(p));
2360 		p.iph.daddr = ireq.ifr6_addr.s6_addr32[3];
2361 		p.iph.saddr = 0;
2362 		p.iph.version = 4;
2363 		p.iph.ihl = 5;
2364 		p.iph.protocol = IPPROTO_IPV6;
2365 		p.iph.ttl = 64;
2366 		ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
2367 
2368 		if (ops->ndo_do_ioctl) {
2369 			mm_segment_t oldfs = get_fs();
2370 
2371 			set_fs(KERNEL_DS);
2372 			err = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
2373 			set_fs(oldfs);
2374 		} else
2375 			err = -EOPNOTSUPP;
2376 
2377 		if (err == 0) {
2378 			err = -ENOBUFS;
2379 			dev = __dev_get_by_name(net, p.name);
2380 			if (!dev)
2381 				goto err_exit;
2382 			err = dev_open(dev);
2383 		}
2384 	}
2385 #endif
2386 
2387 err_exit:
2388 	rtnl_unlock();
2389 	return err;
2390 }
2391 
2392 /*
2393  *	Manual configuration of address on an interface
2394  */
2395 static int inet6_addr_add(struct net *net, int ifindex, const struct in6_addr *pfx,
2396 			  unsigned int plen, __u8 ifa_flags, __u32 prefered_lft,
2397 			  __u32 valid_lft)
2398 {
2399 	struct inet6_ifaddr *ifp;
2400 	struct inet6_dev *idev;
2401 	struct net_device *dev;
2402 	int scope;
2403 	u32 flags;
2404 	clock_t expires;
2405 	unsigned long timeout;
2406 
2407 	ASSERT_RTNL();
2408 
2409 	if (plen > 128)
2410 		return -EINVAL;
2411 
2412 	/* check the lifetime */
2413 	if (!valid_lft || prefered_lft > valid_lft)
2414 		return -EINVAL;
2415 
2416 	dev = __dev_get_by_index(net, ifindex);
2417 	if (!dev)
2418 		return -ENODEV;
2419 
2420 	idev = addrconf_add_dev(dev);
2421 	if (IS_ERR(idev))
2422 		return PTR_ERR(idev);
2423 
2424 	scope = ipv6_addr_scope(pfx);
2425 
2426 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
2427 	if (addrconf_finite_timeout(timeout)) {
2428 		expires = jiffies_to_clock_t(timeout * HZ);
2429 		valid_lft = timeout;
2430 		flags = RTF_EXPIRES;
2431 	} else {
2432 		expires = 0;
2433 		flags = 0;
2434 		ifa_flags |= IFA_F_PERMANENT;
2435 	}
2436 
2437 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
2438 	if (addrconf_finite_timeout(timeout)) {
2439 		if (timeout == 0)
2440 			ifa_flags |= IFA_F_DEPRECATED;
2441 		prefered_lft = timeout;
2442 	}
2443 
2444 	ifp = ipv6_add_addr(idev, pfx, plen, scope, ifa_flags);
2445 
2446 	if (!IS_ERR(ifp)) {
2447 		spin_lock_bh(&ifp->lock);
2448 		ifp->valid_lft = valid_lft;
2449 		ifp->prefered_lft = prefered_lft;
2450 		ifp->tstamp = jiffies;
2451 		spin_unlock_bh(&ifp->lock);
2452 
2453 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, dev,
2454 				      expires, flags);
2455 		/*
2456 		 * Note that section 3.1 of RFC 4429 indicates
2457 		 * that the Optimistic flag should not be set for
2458 		 * manually configured addresses
2459 		 */
2460 		addrconf_dad_start(ifp);
2461 		in6_ifa_put(ifp);
2462 		addrconf_verify(0);
2463 		return 0;
2464 	}
2465 
2466 	return PTR_ERR(ifp);
2467 }
2468 
2469 static int inet6_addr_del(struct net *net, int ifindex, const struct in6_addr *pfx,
2470 			  unsigned int plen)
2471 {
2472 	struct inet6_ifaddr *ifp;
2473 	struct inet6_dev *idev;
2474 	struct net_device *dev;
2475 
2476 	if (plen > 128)
2477 		return -EINVAL;
2478 
2479 	dev = __dev_get_by_index(net, ifindex);
2480 	if (!dev)
2481 		return -ENODEV;
2482 
2483 	if ((idev = __in6_dev_get(dev)) == NULL)
2484 		return -ENXIO;
2485 
2486 	read_lock_bh(&idev->lock);
2487 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
2488 		if (ifp->prefix_len == plen &&
2489 		    ipv6_addr_equal(pfx, &ifp->addr)) {
2490 			in6_ifa_hold(ifp);
2491 			read_unlock_bh(&idev->lock);
2492 
2493 			ipv6_del_addr(ifp);
2494 
2495 			/* If the last address is deleted administratively,
2496 			   disable IPv6 on this interface.
2497 			 */
2498 			if (list_empty(&idev->addr_list))
2499 				addrconf_ifdown(idev->dev, 1);
2500 			return 0;
2501 		}
2502 	}
2503 	read_unlock_bh(&idev->lock);
2504 	return -EADDRNOTAVAIL;
2505 }
2506 
2507 
2508 int addrconf_add_ifaddr(struct net *net, void __user *arg)
2509 {
2510 	struct in6_ifreq ireq;
2511 	int err;
2512 
2513 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2514 		return -EPERM;
2515 
2516 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2517 		return -EFAULT;
2518 
2519 	rtnl_lock();
2520 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &ireq.ifr6_addr,
2521 			     ireq.ifr6_prefixlen, IFA_F_PERMANENT,
2522 			     INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
2523 	rtnl_unlock();
2524 	return err;
2525 }
2526 
2527 int addrconf_del_ifaddr(struct net *net, void __user *arg)
2528 {
2529 	struct in6_ifreq ireq;
2530 	int err;
2531 
2532 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2533 		return -EPERM;
2534 
2535 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2536 		return -EFAULT;
2537 
2538 	rtnl_lock();
2539 	err = inet6_addr_del(net, ireq.ifr6_ifindex, &ireq.ifr6_addr,
2540 			     ireq.ifr6_prefixlen);
2541 	rtnl_unlock();
2542 	return err;
2543 }
2544 
2545 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
2546 		     int plen, int scope)
2547 {
2548 	struct inet6_ifaddr *ifp;
2549 
2550 	ifp = ipv6_add_addr(idev, addr, plen, scope, IFA_F_PERMANENT);
2551 	if (!IS_ERR(ifp)) {
2552 		spin_lock_bh(&ifp->lock);
2553 		ifp->flags &= ~IFA_F_TENTATIVE;
2554 		spin_unlock_bh(&ifp->lock);
2555 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
2556 		in6_ifa_put(ifp);
2557 	}
2558 }
2559 
2560 #if IS_ENABLED(CONFIG_IPV6_SIT)
2561 static void sit_add_v4_addrs(struct inet6_dev *idev)
2562 {
2563 	struct in6_addr addr;
2564 	struct net_device *dev;
2565 	struct net *net = dev_net(idev->dev);
2566 	int scope;
2567 
2568 	ASSERT_RTNL();
2569 
2570 	memset(&addr, 0, sizeof(struct in6_addr));
2571 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
2572 
2573 	if (idev->dev->flags&IFF_POINTOPOINT) {
2574 		addr.s6_addr32[0] = htonl(0xfe800000);
2575 		scope = IFA_LINK;
2576 	} else {
2577 		scope = IPV6_ADDR_COMPATv4;
2578 	}
2579 
2580 	if (addr.s6_addr32[3]) {
2581 		add_addr(idev, &addr, 128, scope);
2582 		return;
2583 	}
2584 
2585 	for_each_netdev(net, dev) {
2586 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
2587 		if (in_dev && (dev->flags & IFF_UP)) {
2588 			struct in_ifaddr *ifa;
2589 
2590 			int flag = scope;
2591 
2592 			for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
2593 				int plen;
2594 
2595 				addr.s6_addr32[3] = ifa->ifa_local;
2596 
2597 				if (ifa->ifa_scope == RT_SCOPE_LINK)
2598 					continue;
2599 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
2600 					if (idev->dev->flags&IFF_POINTOPOINT)
2601 						continue;
2602 					flag |= IFA_HOST;
2603 				}
2604 				if (idev->dev->flags&IFF_POINTOPOINT)
2605 					plen = 64;
2606 				else
2607 					plen = 96;
2608 
2609 				add_addr(idev, &addr, plen, flag);
2610 			}
2611 		}
2612 	}
2613 }
2614 #endif
2615 
2616 static void init_loopback(struct net_device *dev)
2617 {
2618 	struct inet6_dev  *idev;
2619 
2620 	/* ::1 */
2621 
2622 	ASSERT_RTNL();
2623 
2624 	if ((idev = ipv6_find_idev(dev)) == NULL) {
2625 		pr_debug("%s: add_dev failed\n", __func__);
2626 		return;
2627 	}
2628 
2629 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST);
2630 }
2631 
2632 static void addrconf_add_linklocal(struct inet6_dev *idev, const struct in6_addr *addr)
2633 {
2634 	struct inet6_ifaddr *ifp;
2635 	u32 addr_flags = IFA_F_PERMANENT;
2636 
2637 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2638 	if (idev->cnf.optimistic_dad &&
2639 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
2640 		addr_flags |= IFA_F_OPTIMISTIC;
2641 #endif
2642 
2643 
2644 	ifp = ipv6_add_addr(idev, addr, 64, IFA_LINK, addr_flags);
2645 	if (!IS_ERR(ifp)) {
2646 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, idev->dev, 0, 0);
2647 		addrconf_dad_start(ifp);
2648 		in6_ifa_put(ifp);
2649 	}
2650 }
2651 
2652 static void addrconf_dev_config(struct net_device *dev)
2653 {
2654 	struct in6_addr addr;
2655 	struct inet6_dev *idev;
2656 
2657 	ASSERT_RTNL();
2658 
2659 	if ((dev->type != ARPHRD_ETHER) &&
2660 	    (dev->type != ARPHRD_FDDI) &&
2661 	    (dev->type != ARPHRD_ARCNET) &&
2662 	    (dev->type != ARPHRD_INFINIBAND) &&
2663 	    (dev->type != ARPHRD_IEEE802154) &&
2664 	    (dev->type != ARPHRD_IEEE1394)) {
2665 		/* Alas, we support only Ethernet autoconfiguration. */
2666 		return;
2667 	}
2668 
2669 	idev = addrconf_add_dev(dev);
2670 	if (IS_ERR(idev))
2671 		return;
2672 
2673 	memset(&addr, 0, sizeof(struct in6_addr));
2674 	addr.s6_addr32[0] = htonl(0xFE800000);
2675 
2676 	if (ipv6_generate_eui64(addr.s6_addr + 8, dev) == 0)
2677 		addrconf_add_linklocal(idev, &addr);
2678 }
2679 
2680 #if IS_ENABLED(CONFIG_IPV6_SIT)
2681 static void addrconf_sit_config(struct net_device *dev)
2682 {
2683 	struct inet6_dev *idev;
2684 
2685 	ASSERT_RTNL();
2686 
2687 	/*
2688 	 * Configure the tunnel with one of our IPv4
2689 	 * addresses... we should configure all of
2690 	 * our v4 addrs in the tunnel
2691 	 */
2692 
2693 	if ((idev = ipv6_find_idev(dev)) == NULL) {
2694 		pr_debug("%s: add_dev failed\n", __func__);
2695 		return;
2696 	}
2697 
2698 	if (dev->priv_flags & IFF_ISATAP) {
2699 		struct in6_addr addr;
2700 
2701 		ipv6_addr_set(&addr,  htonl(0xFE800000), 0, 0, 0);
2702 		addrconf_prefix_route(&addr, 64, dev, 0, 0);
2703 		if (!ipv6_generate_eui64(addr.s6_addr + 8, dev))
2704 			addrconf_add_linklocal(idev, &addr);
2705 		return;
2706 	}
2707 
2708 	sit_add_v4_addrs(idev);
2709 
2710 	if (dev->flags&IFF_POINTOPOINT)
2711 		addrconf_add_mroute(dev);
2712 	else
2713 		sit_route_add(dev);
2714 }
2715 #endif
2716 
2717 #if IS_ENABLED(CONFIG_NET_IPGRE)
2718 static void addrconf_gre_config(struct net_device *dev)
2719 {
2720 	struct inet6_dev *idev;
2721 	struct in6_addr addr;
2722 
2723 	pr_info("%s(%s)\n", __func__, dev->name);
2724 
2725 	ASSERT_RTNL();
2726 
2727 	if ((idev = ipv6_find_idev(dev)) == NULL) {
2728 		pr_debug("%s: add_dev failed\n", __func__);
2729 		return;
2730 	}
2731 
2732 	ipv6_addr_set(&addr,  htonl(0xFE800000), 0, 0, 0);
2733 	addrconf_prefix_route(&addr, 64, dev, 0, 0);
2734 
2735 	if (!ipv6_generate_eui64(addr.s6_addr + 8, dev))
2736 		addrconf_add_linklocal(idev, &addr);
2737 }
2738 #endif
2739 
2740 static inline int
2741 ipv6_inherit_linklocal(struct inet6_dev *idev, struct net_device *link_dev)
2742 {
2743 	struct in6_addr lladdr;
2744 
2745 	if (!ipv6_get_lladdr(link_dev, &lladdr, IFA_F_TENTATIVE)) {
2746 		addrconf_add_linklocal(idev, &lladdr);
2747 		return 0;
2748 	}
2749 	return -1;
2750 }
2751 
2752 static void ip6_tnl_add_linklocal(struct inet6_dev *idev)
2753 {
2754 	struct net_device *link_dev;
2755 	struct net *net = dev_net(idev->dev);
2756 
2757 	/* first try to inherit the link-local address from the link device */
2758 	if (idev->dev->iflink &&
2759 	    (link_dev = __dev_get_by_index(net, idev->dev->iflink))) {
2760 		if (!ipv6_inherit_linklocal(idev, link_dev))
2761 			return;
2762 	}
2763 	/* then try to inherit it from any device */
2764 	for_each_netdev(net, link_dev) {
2765 		if (!ipv6_inherit_linklocal(idev, link_dev))
2766 			return;
2767 	}
2768 	pr_debug("init ip6-ip6: add_linklocal failed\n");
2769 }
2770 
2771 /*
2772  * Autoconfigure tunnel with a link-local address so routing protocols,
2773  * DHCPv6, MLD etc. can be run over the virtual link
2774  */
2775 
2776 static void addrconf_ip6_tnl_config(struct net_device *dev)
2777 {
2778 	struct inet6_dev *idev;
2779 
2780 	ASSERT_RTNL();
2781 
2782 	idev = addrconf_add_dev(dev);
2783 	if (IS_ERR(idev)) {
2784 		pr_debug("init ip6-ip6: add_dev failed\n");
2785 		return;
2786 	}
2787 	ip6_tnl_add_linklocal(idev);
2788 }
2789 
2790 static int addrconf_notify(struct notifier_block *this, unsigned long event,
2791 			   void *data)
2792 {
2793 	struct net_device *dev = (struct net_device *) data;
2794 	struct inet6_dev *idev = __in6_dev_get(dev);
2795 	int run_pending = 0;
2796 	int err;
2797 
2798 	switch (event) {
2799 	case NETDEV_REGISTER:
2800 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
2801 			idev = ipv6_add_dev(dev);
2802 			if (!idev)
2803 				return notifier_from_errno(-ENOMEM);
2804 		}
2805 		break;
2806 
2807 	case NETDEV_UP:
2808 	case NETDEV_CHANGE:
2809 		if (dev->flags & IFF_SLAVE)
2810 			break;
2811 
2812 		if (event == NETDEV_UP) {
2813 			if (!addrconf_qdisc_ok(dev)) {
2814 				/* device is not ready yet. */
2815 				pr_info("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
2816 					dev->name);
2817 				break;
2818 			}
2819 
2820 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
2821 				idev = ipv6_add_dev(dev);
2822 
2823 			if (idev) {
2824 				idev->if_flags |= IF_READY;
2825 				run_pending = 1;
2826 			}
2827 		} else {
2828 			if (!addrconf_qdisc_ok(dev)) {
2829 				/* device is still not ready. */
2830 				break;
2831 			}
2832 
2833 			if (idev) {
2834 				if (idev->if_flags & IF_READY)
2835 					/* device is already configured. */
2836 					break;
2837 				idev->if_flags |= IF_READY;
2838 			}
2839 
2840 			pr_info("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
2841 				dev->name);
2842 
2843 			run_pending = 1;
2844 		}
2845 
2846 		switch (dev->type) {
2847 #if IS_ENABLED(CONFIG_IPV6_SIT)
2848 		case ARPHRD_SIT:
2849 			addrconf_sit_config(dev);
2850 			break;
2851 #endif
2852 #if IS_ENABLED(CONFIG_NET_IPGRE)
2853 		case ARPHRD_IPGRE:
2854 			addrconf_gre_config(dev);
2855 			break;
2856 #endif
2857 		case ARPHRD_TUNNEL6:
2858 			addrconf_ip6_tnl_config(dev);
2859 			break;
2860 		case ARPHRD_LOOPBACK:
2861 			init_loopback(dev);
2862 			break;
2863 
2864 		default:
2865 			addrconf_dev_config(dev);
2866 			break;
2867 		}
2868 
2869 		if (idev) {
2870 			if (run_pending)
2871 				addrconf_dad_run(idev);
2872 
2873 			/*
2874 			 * If the MTU changed during the interface down,
2875 			 * when the interface up, the changed MTU must be
2876 			 * reflected in the idev as well as routers.
2877 			 */
2878 			if (idev->cnf.mtu6 != dev->mtu &&
2879 			    dev->mtu >= IPV6_MIN_MTU) {
2880 				rt6_mtu_change(dev, dev->mtu);
2881 				idev->cnf.mtu6 = dev->mtu;
2882 			}
2883 			idev->tstamp = jiffies;
2884 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
2885 
2886 			/*
2887 			 * If the changed mtu during down is lower than
2888 			 * IPV6_MIN_MTU stop IPv6 on this interface.
2889 			 */
2890 			if (dev->mtu < IPV6_MIN_MTU)
2891 				addrconf_ifdown(dev, 1);
2892 		}
2893 		break;
2894 
2895 	case NETDEV_CHANGEMTU:
2896 		if (idev && dev->mtu >= IPV6_MIN_MTU) {
2897 			rt6_mtu_change(dev, dev->mtu);
2898 			idev->cnf.mtu6 = dev->mtu;
2899 			break;
2900 		}
2901 
2902 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
2903 			idev = ipv6_add_dev(dev);
2904 			if (idev)
2905 				break;
2906 		}
2907 
2908 		/*
2909 		 * MTU falled under IPV6_MIN_MTU.
2910 		 * Stop IPv6 on this interface.
2911 		 */
2912 
2913 	case NETDEV_DOWN:
2914 	case NETDEV_UNREGISTER:
2915 		/*
2916 		 *	Remove all addresses from this interface.
2917 		 */
2918 		addrconf_ifdown(dev, event != NETDEV_DOWN);
2919 		break;
2920 
2921 	case NETDEV_CHANGENAME:
2922 		if (idev) {
2923 			snmp6_unregister_dev(idev);
2924 			addrconf_sysctl_unregister(idev);
2925 			addrconf_sysctl_register(idev);
2926 			err = snmp6_register_dev(idev);
2927 			if (err)
2928 				return notifier_from_errno(err);
2929 		}
2930 		break;
2931 
2932 	case NETDEV_PRE_TYPE_CHANGE:
2933 	case NETDEV_POST_TYPE_CHANGE:
2934 		addrconf_type_change(dev, event);
2935 		break;
2936 	}
2937 
2938 	return NOTIFY_OK;
2939 }
2940 
2941 /*
2942  *	addrconf module should be notified of a device going up
2943  */
2944 static struct notifier_block ipv6_dev_notf = {
2945 	.notifier_call = addrconf_notify,
2946 };
2947 
2948 static void addrconf_type_change(struct net_device *dev, unsigned long event)
2949 {
2950 	struct inet6_dev *idev;
2951 	ASSERT_RTNL();
2952 
2953 	idev = __in6_dev_get(dev);
2954 
2955 	if (event == NETDEV_POST_TYPE_CHANGE)
2956 		ipv6_mc_remap(idev);
2957 	else if (event == NETDEV_PRE_TYPE_CHANGE)
2958 		ipv6_mc_unmap(idev);
2959 }
2960 
2961 static int addrconf_ifdown(struct net_device *dev, int how)
2962 {
2963 	struct net *net = dev_net(dev);
2964 	struct inet6_dev *idev;
2965 	struct inet6_ifaddr *ifa;
2966 	int state, i;
2967 
2968 	ASSERT_RTNL();
2969 
2970 	rt6_ifdown(net, dev);
2971 	neigh_ifdown(&nd_tbl, dev);
2972 
2973 	idev = __in6_dev_get(dev);
2974 	if (idev == NULL)
2975 		return -ENODEV;
2976 
2977 	/*
2978 	 * Step 1: remove reference to ipv6 device from parent device.
2979 	 *	   Do not dev_put!
2980 	 */
2981 	if (how) {
2982 		idev->dead = 1;
2983 
2984 		/* protected by rtnl_lock */
2985 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
2986 
2987 		/* Step 1.5: remove snmp6 entry */
2988 		snmp6_unregister_dev(idev);
2989 
2990 	}
2991 
2992 	/* Step 2: clear hash table */
2993 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
2994 		struct hlist_head *h = &inet6_addr_lst[i];
2995 
2996 		spin_lock_bh(&addrconf_hash_lock);
2997 	restart:
2998 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
2999 			if (ifa->idev == idev) {
3000 				hlist_del_init_rcu(&ifa->addr_lst);
3001 				addrconf_del_timer(ifa);
3002 				goto restart;
3003 			}
3004 		}
3005 		spin_unlock_bh(&addrconf_hash_lock);
3006 	}
3007 
3008 	write_lock_bh(&idev->lock);
3009 
3010 	/* Step 2: clear flags for stateless addrconf */
3011 	if (!how)
3012 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3013 
3014 #ifdef CONFIG_IPV6_PRIVACY
3015 	if (how && del_timer(&idev->regen_timer))
3016 		in6_dev_put(idev);
3017 
3018 	/* Step 3: clear tempaddr list */
3019 	while (!list_empty(&idev->tempaddr_list)) {
3020 		ifa = list_first_entry(&idev->tempaddr_list,
3021 				       struct inet6_ifaddr, tmp_list);
3022 		list_del(&ifa->tmp_list);
3023 		write_unlock_bh(&idev->lock);
3024 		spin_lock_bh(&ifa->lock);
3025 
3026 		if (ifa->ifpub) {
3027 			in6_ifa_put(ifa->ifpub);
3028 			ifa->ifpub = NULL;
3029 		}
3030 		spin_unlock_bh(&ifa->lock);
3031 		in6_ifa_put(ifa);
3032 		write_lock_bh(&idev->lock);
3033 	}
3034 #endif
3035 
3036 	while (!list_empty(&idev->addr_list)) {
3037 		ifa = list_first_entry(&idev->addr_list,
3038 				       struct inet6_ifaddr, if_list);
3039 		addrconf_del_timer(ifa);
3040 
3041 		list_del(&ifa->if_list);
3042 
3043 		write_unlock_bh(&idev->lock);
3044 
3045 		spin_lock_bh(&ifa->state_lock);
3046 		state = ifa->state;
3047 		ifa->state = INET6_IFADDR_STATE_DEAD;
3048 		spin_unlock_bh(&ifa->state_lock);
3049 
3050 		if (state != INET6_IFADDR_STATE_DEAD) {
3051 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
3052 			atomic_notifier_call_chain(&inet6addr_chain, NETDEV_DOWN, ifa);
3053 		}
3054 		in6_ifa_put(ifa);
3055 
3056 		write_lock_bh(&idev->lock);
3057 	}
3058 
3059 	write_unlock_bh(&idev->lock);
3060 
3061 	/* Step 5: Discard multicast list */
3062 	if (how)
3063 		ipv6_mc_destroy_dev(idev);
3064 	else
3065 		ipv6_mc_down(idev);
3066 
3067 	idev->tstamp = jiffies;
3068 
3069 	/* Last: Shot the device (if unregistered) */
3070 	if (how) {
3071 		addrconf_sysctl_unregister(idev);
3072 		neigh_parms_release(&nd_tbl, idev->nd_parms);
3073 		neigh_ifdown(&nd_tbl, dev);
3074 		in6_dev_put(idev);
3075 	}
3076 	return 0;
3077 }
3078 
3079 static void addrconf_rs_timer(unsigned long data)
3080 {
3081 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *) data;
3082 	struct inet6_dev *idev = ifp->idev;
3083 
3084 	read_lock(&idev->lock);
3085 	if (idev->dead || !(idev->if_flags & IF_READY))
3086 		goto out;
3087 
3088 	if (!ipv6_accept_ra(idev))
3089 		goto out;
3090 
3091 	/* Announcement received after solicitation was sent */
3092 	if (idev->if_flags & IF_RA_RCVD)
3093 		goto out;
3094 
3095 	spin_lock(&ifp->lock);
3096 	if (ifp->probes++ < idev->cnf.rtr_solicits) {
3097 		/* The wait after the last probe can be shorter */
3098 		addrconf_mod_timer(ifp, AC_RS,
3099 				   (ifp->probes == idev->cnf.rtr_solicits) ?
3100 				   idev->cnf.rtr_solicit_delay :
3101 				   idev->cnf.rtr_solicit_interval);
3102 		spin_unlock(&ifp->lock);
3103 
3104 		ndisc_send_rs(idev->dev, &ifp->addr, &in6addr_linklocal_allrouters);
3105 	} else {
3106 		spin_unlock(&ifp->lock);
3107 		/*
3108 		 * Note: we do not support deprecated "all on-link"
3109 		 * assumption any longer.
3110 		 */
3111 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
3112 	}
3113 
3114 out:
3115 	read_unlock(&idev->lock);
3116 	in6_ifa_put(ifp);
3117 }
3118 
3119 /*
3120  *	Duplicate Address Detection
3121  */
3122 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
3123 {
3124 	unsigned long rand_num;
3125 	struct inet6_dev *idev = ifp->idev;
3126 
3127 	if (ifp->flags & IFA_F_OPTIMISTIC)
3128 		rand_num = 0;
3129 	else
3130 		rand_num = net_random() % (idev->cnf.rtr_solicit_delay ? : 1);
3131 
3132 	ifp->probes = idev->cnf.dad_transmits;
3133 	addrconf_mod_timer(ifp, AC_DAD, rand_num);
3134 }
3135 
3136 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
3137 {
3138 	struct inet6_dev *idev = ifp->idev;
3139 	struct net_device *dev = idev->dev;
3140 
3141 	addrconf_join_solict(dev, &ifp->addr);
3142 
3143 	net_srandom(ifp->addr.s6_addr32[3]);
3144 
3145 	read_lock_bh(&idev->lock);
3146 	spin_lock(&ifp->lock);
3147 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
3148 		goto out;
3149 
3150 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
3151 	    idev->cnf.accept_dad < 1 ||
3152 	    !(ifp->flags&IFA_F_TENTATIVE) ||
3153 	    ifp->flags & IFA_F_NODAD) {
3154 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3155 		spin_unlock(&ifp->lock);
3156 		read_unlock_bh(&idev->lock);
3157 
3158 		addrconf_dad_completed(ifp);
3159 		return;
3160 	}
3161 
3162 	if (!(idev->if_flags & IF_READY)) {
3163 		spin_unlock(&ifp->lock);
3164 		read_unlock_bh(&idev->lock);
3165 		/*
3166 		 * If the device is not ready:
3167 		 * - keep it tentative if it is a permanent address.
3168 		 * - otherwise, kill it.
3169 		 */
3170 		in6_ifa_hold(ifp);
3171 		addrconf_dad_stop(ifp, 0);
3172 		return;
3173 	}
3174 
3175 	/*
3176 	 * Optimistic nodes can start receiving
3177 	 * Frames right away
3178 	 */
3179 	if (ifp->flags & IFA_F_OPTIMISTIC)
3180 		ip6_ins_rt(ifp->rt);
3181 
3182 	addrconf_dad_kick(ifp);
3183 out:
3184 	spin_unlock(&ifp->lock);
3185 	read_unlock_bh(&idev->lock);
3186 }
3187 
3188 static void addrconf_dad_timer(unsigned long data)
3189 {
3190 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *) data;
3191 	struct inet6_dev *idev = ifp->idev;
3192 	struct in6_addr mcaddr;
3193 
3194 	if (!ifp->probes && addrconf_dad_end(ifp))
3195 		goto out;
3196 
3197 	read_lock(&idev->lock);
3198 	if (idev->dead || !(idev->if_flags & IF_READY)) {
3199 		read_unlock(&idev->lock);
3200 		goto out;
3201 	}
3202 
3203 	spin_lock(&ifp->lock);
3204 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
3205 		spin_unlock(&ifp->lock);
3206 		read_unlock(&idev->lock);
3207 		goto out;
3208 	}
3209 
3210 	if (ifp->probes == 0) {
3211 		/*
3212 		 * DAD was successful
3213 		 */
3214 
3215 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3216 		spin_unlock(&ifp->lock);
3217 		read_unlock(&idev->lock);
3218 
3219 		addrconf_dad_completed(ifp);
3220 
3221 		goto out;
3222 	}
3223 
3224 	ifp->probes--;
3225 	addrconf_mod_timer(ifp, AC_DAD, ifp->idev->nd_parms->retrans_time);
3226 	spin_unlock(&ifp->lock);
3227 	read_unlock(&idev->lock);
3228 
3229 	/* send a neighbour solicitation for our addr */
3230 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
3231 	ndisc_send_ns(ifp->idev->dev, NULL, &ifp->addr, &mcaddr, &in6addr_any);
3232 out:
3233 	in6_ifa_put(ifp);
3234 }
3235 
3236 static void addrconf_dad_completed(struct inet6_ifaddr *ifp)
3237 {
3238 	struct net_device *dev = ifp->idev->dev;
3239 
3240 	/*
3241 	 *	Configure the address for reception. Now it is valid.
3242 	 */
3243 
3244 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
3245 
3246 	/* If added prefix is link local and we are prepared to process
3247 	   router advertisements, start sending router solicitations.
3248 	 */
3249 
3250 	if (ipv6_accept_ra(ifp->idev) &&
3251 	    ifp->idev->cnf.rtr_solicits > 0 &&
3252 	    (dev->flags&IFF_LOOPBACK) == 0 &&
3253 	    (ipv6_addr_type(&ifp->addr) & IPV6_ADDR_LINKLOCAL)) {
3254 		/*
3255 		 *	If a host as already performed a random delay
3256 		 *	[...] as part of DAD [...] there is no need
3257 		 *	to delay again before sending the first RS
3258 		 */
3259 		ndisc_send_rs(ifp->idev->dev, &ifp->addr, &in6addr_linklocal_allrouters);
3260 
3261 		spin_lock_bh(&ifp->lock);
3262 		ifp->probes = 1;
3263 		ifp->idev->if_flags |= IF_RS_SENT;
3264 		addrconf_mod_timer(ifp, AC_RS, ifp->idev->cnf.rtr_solicit_interval);
3265 		spin_unlock_bh(&ifp->lock);
3266 	}
3267 }
3268 
3269 static void addrconf_dad_run(struct inet6_dev *idev)
3270 {
3271 	struct inet6_ifaddr *ifp;
3272 
3273 	read_lock_bh(&idev->lock);
3274 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
3275 		spin_lock(&ifp->lock);
3276 		if (ifp->flags & IFA_F_TENTATIVE &&
3277 		    ifp->state == INET6_IFADDR_STATE_DAD)
3278 			addrconf_dad_kick(ifp);
3279 		spin_unlock(&ifp->lock);
3280 	}
3281 	read_unlock_bh(&idev->lock);
3282 }
3283 
3284 #ifdef CONFIG_PROC_FS
3285 struct if6_iter_state {
3286 	struct seq_net_private p;
3287 	int bucket;
3288 	int offset;
3289 };
3290 
3291 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
3292 {
3293 	struct inet6_ifaddr *ifa = NULL;
3294 	struct if6_iter_state *state = seq->private;
3295 	struct net *net = seq_file_net(seq);
3296 	int p = 0;
3297 
3298 	/* initial bucket if pos is 0 */
3299 	if (pos == 0) {
3300 		state->bucket = 0;
3301 		state->offset = 0;
3302 	}
3303 
3304 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
3305 		hlist_for_each_entry_rcu_bh(ifa, &inet6_addr_lst[state->bucket],
3306 					 addr_lst) {
3307 			if (!net_eq(dev_net(ifa->idev->dev), net))
3308 				continue;
3309 			/* sync with offset */
3310 			if (p < state->offset) {
3311 				p++;
3312 				continue;
3313 			}
3314 			state->offset++;
3315 			return ifa;
3316 		}
3317 
3318 		/* prepare for next bucket */
3319 		state->offset = 0;
3320 		p = 0;
3321 	}
3322 	return NULL;
3323 }
3324 
3325 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
3326 					 struct inet6_ifaddr *ifa)
3327 {
3328 	struct if6_iter_state *state = seq->private;
3329 	struct net *net = seq_file_net(seq);
3330 
3331 	hlist_for_each_entry_continue_rcu_bh(ifa, addr_lst) {
3332 		if (!net_eq(dev_net(ifa->idev->dev), net))
3333 			continue;
3334 		state->offset++;
3335 		return ifa;
3336 	}
3337 
3338 	while (++state->bucket < IN6_ADDR_HSIZE) {
3339 		state->offset = 0;
3340 		hlist_for_each_entry_rcu_bh(ifa,
3341 				     &inet6_addr_lst[state->bucket], addr_lst) {
3342 			if (!net_eq(dev_net(ifa->idev->dev), net))
3343 				continue;
3344 			state->offset++;
3345 			return ifa;
3346 		}
3347 	}
3348 
3349 	return NULL;
3350 }
3351 
3352 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
3353 	__acquires(rcu_bh)
3354 {
3355 	rcu_read_lock_bh();
3356 	return if6_get_first(seq, *pos);
3357 }
3358 
3359 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3360 {
3361 	struct inet6_ifaddr *ifa;
3362 
3363 	ifa = if6_get_next(seq, v);
3364 	++*pos;
3365 	return ifa;
3366 }
3367 
3368 static void if6_seq_stop(struct seq_file *seq, void *v)
3369 	__releases(rcu_bh)
3370 {
3371 	rcu_read_unlock_bh();
3372 }
3373 
3374 static int if6_seq_show(struct seq_file *seq, void *v)
3375 {
3376 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
3377 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
3378 		   &ifp->addr,
3379 		   ifp->idev->dev->ifindex,
3380 		   ifp->prefix_len,
3381 		   ifp->scope,
3382 		   ifp->flags,
3383 		   ifp->idev->dev->name);
3384 	return 0;
3385 }
3386 
3387 static const struct seq_operations if6_seq_ops = {
3388 	.start	= if6_seq_start,
3389 	.next	= if6_seq_next,
3390 	.show	= if6_seq_show,
3391 	.stop	= if6_seq_stop,
3392 };
3393 
3394 static int if6_seq_open(struct inode *inode, struct file *file)
3395 {
3396 	return seq_open_net(inode, file, &if6_seq_ops,
3397 			    sizeof(struct if6_iter_state));
3398 }
3399 
3400 static const struct file_operations if6_fops = {
3401 	.owner		= THIS_MODULE,
3402 	.open		= if6_seq_open,
3403 	.read		= seq_read,
3404 	.llseek		= seq_lseek,
3405 	.release	= seq_release_net,
3406 };
3407 
3408 static int __net_init if6_proc_net_init(struct net *net)
3409 {
3410 	if (!proc_create("if_inet6", S_IRUGO, net->proc_net, &if6_fops))
3411 		return -ENOMEM;
3412 	return 0;
3413 }
3414 
3415 static void __net_exit if6_proc_net_exit(struct net *net)
3416 {
3417 	remove_proc_entry("if_inet6", net->proc_net);
3418 }
3419 
3420 static struct pernet_operations if6_proc_net_ops = {
3421        .init = if6_proc_net_init,
3422        .exit = if6_proc_net_exit,
3423 };
3424 
3425 int __init if6_proc_init(void)
3426 {
3427 	return register_pernet_subsys(&if6_proc_net_ops);
3428 }
3429 
3430 void if6_proc_exit(void)
3431 {
3432 	unregister_pernet_subsys(&if6_proc_net_ops);
3433 }
3434 #endif	/* CONFIG_PROC_FS */
3435 
3436 #if IS_ENABLED(CONFIG_IPV6_MIP6)
3437 /* Check if address is a home address configured on any interface. */
3438 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
3439 {
3440 	int ret = 0;
3441 	struct inet6_ifaddr *ifp = NULL;
3442 	unsigned int hash = inet6_addr_hash(addr);
3443 
3444 	rcu_read_lock_bh();
3445 	hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[hash], addr_lst) {
3446 		if (!net_eq(dev_net(ifp->idev->dev), net))
3447 			continue;
3448 		if (ipv6_addr_equal(&ifp->addr, addr) &&
3449 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
3450 			ret = 1;
3451 			break;
3452 		}
3453 	}
3454 	rcu_read_unlock_bh();
3455 	return ret;
3456 }
3457 #endif
3458 
3459 /*
3460  *	Periodic address status verification
3461  */
3462 
3463 static void addrconf_verify(unsigned long foo)
3464 {
3465 	unsigned long now, next, next_sec, next_sched;
3466 	struct inet6_ifaddr *ifp;
3467 	int i;
3468 
3469 	rcu_read_lock_bh();
3470 	spin_lock(&addrconf_verify_lock);
3471 	now = jiffies;
3472 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
3473 
3474 	del_timer(&addr_chk_timer);
3475 
3476 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3477 restart:
3478 		hlist_for_each_entry_rcu_bh(ifp,
3479 					 &inet6_addr_lst[i], addr_lst) {
3480 			unsigned long age;
3481 
3482 			if (ifp->flags & IFA_F_PERMANENT)
3483 				continue;
3484 
3485 			spin_lock(&ifp->lock);
3486 			/* We try to batch several events at once. */
3487 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
3488 
3489 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
3490 			    age >= ifp->valid_lft) {
3491 				spin_unlock(&ifp->lock);
3492 				in6_ifa_hold(ifp);
3493 				ipv6_del_addr(ifp);
3494 				goto restart;
3495 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
3496 				spin_unlock(&ifp->lock);
3497 				continue;
3498 			} else if (age >= ifp->prefered_lft) {
3499 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
3500 				int deprecate = 0;
3501 
3502 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
3503 					deprecate = 1;
3504 					ifp->flags |= IFA_F_DEPRECATED;
3505 				}
3506 
3507 				if (time_before(ifp->tstamp + ifp->valid_lft * HZ, next))
3508 					next = ifp->tstamp + ifp->valid_lft * HZ;
3509 
3510 				spin_unlock(&ifp->lock);
3511 
3512 				if (deprecate) {
3513 					in6_ifa_hold(ifp);
3514 
3515 					ipv6_ifa_notify(0, ifp);
3516 					in6_ifa_put(ifp);
3517 					goto restart;
3518 				}
3519 #ifdef CONFIG_IPV6_PRIVACY
3520 			} else if ((ifp->flags&IFA_F_TEMPORARY) &&
3521 				   !(ifp->flags&IFA_F_TENTATIVE)) {
3522 				unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
3523 					ifp->idev->cnf.dad_transmits *
3524 					ifp->idev->nd_parms->retrans_time / HZ;
3525 
3526 				if (age >= ifp->prefered_lft - regen_advance) {
3527 					struct inet6_ifaddr *ifpub = ifp->ifpub;
3528 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
3529 						next = ifp->tstamp + ifp->prefered_lft * HZ;
3530 					if (!ifp->regen_count && ifpub) {
3531 						ifp->regen_count++;
3532 						in6_ifa_hold(ifp);
3533 						in6_ifa_hold(ifpub);
3534 						spin_unlock(&ifp->lock);
3535 
3536 						spin_lock(&ifpub->lock);
3537 						ifpub->regen_count = 0;
3538 						spin_unlock(&ifpub->lock);
3539 						ipv6_create_tempaddr(ifpub, ifp);
3540 						in6_ifa_put(ifpub);
3541 						in6_ifa_put(ifp);
3542 						goto restart;
3543 					}
3544 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
3545 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
3546 				spin_unlock(&ifp->lock);
3547 #endif
3548 			} else {
3549 				/* ifp->prefered_lft <= ifp->valid_lft */
3550 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
3551 					next = ifp->tstamp + ifp->prefered_lft * HZ;
3552 				spin_unlock(&ifp->lock);
3553 			}
3554 		}
3555 	}
3556 
3557 	next_sec = round_jiffies_up(next);
3558 	next_sched = next;
3559 
3560 	/* If rounded timeout is accurate enough, accept it. */
3561 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
3562 		next_sched = next_sec;
3563 
3564 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
3565 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
3566 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
3567 
3568 	ADBG((KERN_DEBUG "now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
3569 	      now, next, next_sec, next_sched));
3570 
3571 	addr_chk_timer.expires = next_sched;
3572 	add_timer(&addr_chk_timer);
3573 	spin_unlock(&addrconf_verify_lock);
3574 	rcu_read_unlock_bh();
3575 }
3576 
3577 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local)
3578 {
3579 	struct in6_addr *pfx = NULL;
3580 
3581 	if (addr)
3582 		pfx = nla_data(addr);
3583 
3584 	if (local) {
3585 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
3586 			pfx = NULL;
3587 		else
3588 			pfx = nla_data(local);
3589 	}
3590 
3591 	return pfx;
3592 }
3593 
3594 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
3595 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
3596 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
3597 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
3598 };
3599 
3600 static int
3601 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh)
3602 {
3603 	struct net *net = sock_net(skb->sk);
3604 	struct ifaddrmsg *ifm;
3605 	struct nlattr *tb[IFA_MAX+1];
3606 	struct in6_addr *pfx;
3607 	int err;
3608 
3609 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
3610 	if (err < 0)
3611 		return err;
3612 
3613 	ifm = nlmsg_data(nlh);
3614 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL]);
3615 	if (pfx == NULL)
3616 		return -EINVAL;
3617 
3618 	return inet6_addr_del(net, ifm->ifa_index, pfx, ifm->ifa_prefixlen);
3619 }
3620 
3621 static int inet6_addr_modify(struct inet6_ifaddr *ifp, u8 ifa_flags,
3622 			     u32 prefered_lft, u32 valid_lft)
3623 {
3624 	u32 flags;
3625 	clock_t expires;
3626 	unsigned long timeout;
3627 
3628 	if (!valid_lft || (prefered_lft > valid_lft))
3629 		return -EINVAL;
3630 
3631 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
3632 	if (addrconf_finite_timeout(timeout)) {
3633 		expires = jiffies_to_clock_t(timeout * HZ);
3634 		valid_lft = timeout;
3635 		flags = RTF_EXPIRES;
3636 	} else {
3637 		expires = 0;
3638 		flags = 0;
3639 		ifa_flags |= IFA_F_PERMANENT;
3640 	}
3641 
3642 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
3643 	if (addrconf_finite_timeout(timeout)) {
3644 		if (timeout == 0)
3645 			ifa_flags |= IFA_F_DEPRECATED;
3646 		prefered_lft = timeout;
3647 	}
3648 
3649 	spin_lock_bh(&ifp->lock);
3650 	ifp->flags = (ifp->flags & ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD | IFA_F_HOMEADDRESS)) | ifa_flags;
3651 	ifp->tstamp = jiffies;
3652 	ifp->valid_lft = valid_lft;
3653 	ifp->prefered_lft = prefered_lft;
3654 
3655 	spin_unlock_bh(&ifp->lock);
3656 	if (!(ifp->flags&IFA_F_TENTATIVE))
3657 		ipv6_ifa_notify(0, ifp);
3658 
3659 	addrconf_prefix_route(&ifp->addr, ifp->prefix_len, ifp->idev->dev,
3660 			      expires, flags);
3661 	addrconf_verify(0);
3662 
3663 	return 0;
3664 }
3665 
3666 static int
3667 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh)
3668 {
3669 	struct net *net = sock_net(skb->sk);
3670 	struct ifaddrmsg *ifm;
3671 	struct nlattr *tb[IFA_MAX+1];
3672 	struct in6_addr *pfx;
3673 	struct inet6_ifaddr *ifa;
3674 	struct net_device *dev;
3675 	u32 valid_lft = INFINITY_LIFE_TIME, preferred_lft = INFINITY_LIFE_TIME;
3676 	u8 ifa_flags;
3677 	int err;
3678 
3679 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
3680 	if (err < 0)
3681 		return err;
3682 
3683 	ifm = nlmsg_data(nlh);
3684 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL]);
3685 	if (pfx == NULL)
3686 		return -EINVAL;
3687 
3688 	if (tb[IFA_CACHEINFO]) {
3689 		struct ifa_cacheinfo *ci;
3690 
3691 		ci = nla_data(tb[IFA_CACHEINFO]);
3692 		valid_lft = ci->ifa_valid;
3693 		preferred_lft = ci->ifa_prefered;
3694 	} else {
3695 		preferred_lft = INFINITY_LIFE_TIME;
3696 		valid_lft = INFINITY_LIFE_TIME;
3697 	}
3698 
3699 	dev =  __dev_get_by_index(net, ifm->ifa_index);
3700 	if (dev == NULL)
3701 		return -ENODEV;
3702 
3703 	/* We ignore other flags so far. */
3704 	ifa_flags = ifm->ifa_flags & (IFA_F_NODAD | IFA_F_HOMEADDRESS);
3705 
3706 	ifa = ipv6_get_ifaddr(net, pfx, dev, 1);
3707 	if (ifa == NULL) {
3708 		/*
3709 		 * It would be best to check for !NLM_F_CREATE here but
3710 		 * userspace alreay relies on not having to provide this.
3711 		 */
3712 		return inet6_addr_add(net, ifm->ifa_index, pfx,
3713 				      ifm->ifa_prefixlen, ifa_flags,
3714 				      preferred_lft, valid_lft);
3715 	}
3716 
3717 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
3718 	    !(nlh->nlmsg_flags & NLM_F_REPLACE))
3719 		err = -EEXIST;
3720 	else
3721 		err = inet6_addr_modify(ifa, ifa_flags, preferred_lft, valid_lft);
3722 
3723 	in6_ifa_put(ifa);
3724 
3725 	return err;
3726 }
3727 
3728 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u8 flags,
3729 			  u8 scope, int ifindex)
3730 {
3731 	struct ifaddrmsg *ifm;
3732 
3733 	ifm = nlmsg_data(nlh);
3734 	ifm->ifa_family = AF_INET6;
3735 	ifm->ifa_prefixlen = prefixlen;
3736 	ifm->ifa_flags = flags;
3737 	ifm->ifa_scope = scope;
3738 	ifm->ifa_index = ifindex;
3739 }
3740 
3741 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
3742 			 unsigned long tstamp, u32 preferred, u32 valid)
3743 {
3744 	struct ifa_cacheinfo ci;
3745 
3746 	ci.cstamp = cstamp_delta(cstamp);
3747 	ci.tstamp = cstamp_delta(tstamp);
3748 	ci.ifa_prefered = preferred;
3749 	ci.ifa_valid = valid;
3750 
3751 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
3752 }
3753 
3754 static inline int rt_scope(int ifa_scope)
3755 {
3756 	if (ifa_scope & IFA_HOST)
3757 		return RT_SCOPE_HOST;
3758 	else if (ifa_scope & IFA_LINK)
3759 		return RT_SCOPE_LINK;
3760 	else if (ifa_scope & IFA_SITE)
3761 		return RT_SCOPE_SITE;
3762 	else
3763 		return RT_SCOPE_UNIVERSE;
3764 }
3765 
3766 static inline int inet6_ifaddr_msgsize(void)
3767 {
3768 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
3769 	       + nla_total_size(16) /* IFA_ADDRESS */
3770 	       + nla_total_size(sizeof(struct ifa_cacheinfo));
3771 }
3772 
3773 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
3774 			     u32 portid, u32 seq, int event, unsigned int flags)
3775 {
3776 	struct nlmsghdr  *nlh;
3777 	u32 preferred, valid;
3778 
3779 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
3780 	if (nlh == NULL)
3781 		return -EMSGSIZE;
3782 
3783 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
3784 		      ifa->idev->dev->ifindex);
3785 
3786 	if (!(ifa->flags&IFA_F_PERMANENT)) {
3787 		preferred = ifa->prefered_lft;
3788 		valid = ifa->valid_lft;
3789 		if (preferred != INFINITY_LIFE_TIME) {
3790 			long tval = (jiffies - ifa->tstamp)/HZ;
3791 			if (preferred > tval)
3792 				preferred -= tval;
3793 			else
3794 				preferred = 0;
3795 			if (valid != INFINITY_LIFE_TIME) {
3796 				if (valid > tval)
3797 					valid -= tval;
3798 				else
3799 					valid = 0;
3800 			}
3801 		}
3802 	} else {
3803 		preferred = INFINITY_LIFE_TIME;
3804 		valid = INFINITY_LIFE_TIME;
3805 	}
3806 
3807 	if (nla_put(skb, IFA_ADDRESS, 16, &ifa->addr) < 0 ||
3808 	    put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0) {
3809 		nlmsg_cancel(skb, nlh);
3810 		return -EMSGSIZE;
3811 	}
3812 
3813 	return nlmsg_end(skb, nlh);
3814 }
3815 
3816 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
3817 				u32 portid, u32 seq, int event, u16 flags)
3818 {
3819 	struct nlmsghdr  *nlh;
3820 	u8 scope = RT_SCOPE_UNIVERSE;
3821 	int ifindex = ifmca->idev->dev->ifindex;
3822 
3823 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
3824 		scope = RT_SCOPE_SITE;
3825 
3826 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
3827 	if (nlh == NULL)
3828 		return -EMSGSIZE;
3829 
3830 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
3831 	if (nla_put(skb, IFA_MULTICAST, 16, &ifmca->mca_addr) < 0 ||
3832 	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
3833 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
3834 		nlmsg_cancel(skb, nlh);
3835 		return -EMSGSIZE;
3836 	}
3837 
3838 	return nlmsg_end(skb, nlh);
3839 }
3840 
3841 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
3842 				u32 portid, u32 seq, int event, unsigned int flags)
3843 {
3844 	struct nlmsghdr  *nlh;
3845 	u8 scope = RT_SCOPE_UNIVERSE;
3846 	int ifindex = ifaca->aca_idev->dev->ifindex;
3847 
3848 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
3849 		scope = RT_SCOPE_SITE;
3850 
3851 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
3852 	if (nlh == NULL)
3853 		return -EMSGSIZE;
3854 
3855 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
3856 	if (nla_put(skb, IFA_ANYCAST, 16, &ifaca->aca_addr) < 0 ||
3857 	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
3858 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
3859 		nlmsg_cancel(skb, nlh);
3860 		return -EMSGSIZE;
3861 	}
3862 
3863 	return nlmsg_end(skb, nlh);
3864 }
3865 
3866 enum addr_type_t {
3867 	UNICAST_ADDR,
3868 	MULTICAST_ADDR,
3869 	ANYCAST_ADDR,
3870 };
3871 
3872 /* called with rcu_read_lock() */
3873 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
3874 			  struct netlink_callback *cb, enum addr_type_t type,
3875 			  int s_ip_idx, int *p_ip_idx)
3876 {
3877 	struct ifmcaddr6 *ifmca;
3878 	struct ifacaddr6 *ifaca;
3879 	int err = 1;
3880 	int ip_idx = *p_ip_idx;
3881 
3882 	read_lock_bh(&idev->lock);
3883 	switch (type) {
3884 	case UNICAST_ADDR: {
3885 		struct inet6_ifaddr *ifa;
3886 
3887 		/* unicast address incl. temp addr */
3888 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
3889 			if (++ip_idx < s_ip_idx)
3890 				continue;
3891 			err = inet6_fill_ifaddr(skb, ifa,
3892 						NETLINK_CB(cb->skb).portid,
3893 						cb->nlh->nlmsg_seq,
3894 						RTM_NEWADDR,
3895 						NLM_F_MULTI);
3896 			if (err <= 0)
3897 				break;
3898 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
3899 		}
3900 		break;
3901 	}
3902 	case MULTICAST_ADDR:
3903 		/* multicast address */
3904 		for (ifmca = idev->mc_list; ifmca;
3905 		     ifmca = ifmca->next, ip_idx++) {
3906 			if (ip_idx < s_ip_idx)
3907 				continue;
3908 			err = inet6_fill_ifmcaddr(skb, ifmca,
3909 						  NETLINK_CB(cb->skb).portid,
3910 						  cb->nlh->nlmsg_seq,
3911 						  RTM_GETMULTICAST,
3912 						  NLM_F_MULTI);
3913 			if (err <= 0)
3914 				break;
3915 		}
3916 		break;
3917 	case ANYCAST_ADDR:
3918 		/* anycast address */
3919 		for (ifaca = idev->ac_list; ifaca;
3920 		     ifaca = ifaca->aca_next, ip_idx++) {
3921 			if (ip_idx < s_ip_idx)
3922 				continue;
3923 			err = inet6_fill_ifacaddr(skb, ifaca,
3924 						  NETLINK_CB(cb->skb).portid,
3925 						  cb->nlh->nlmsg_seq,
3926 						  RTM_GETANYCAST,
3927 						  NLM_F_MULTI);
3928 			if (err <= 0)
3929 				break;
3930 		}
3931 		break;
3932 	default:
3933 		break;
3934 	}
3935 	read_unlock_bh(&idev->lock);
3936 	*p_ip_idx = ip_idx;
3937 	return err;
3938 }
3939 
3940 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
3941 			   enum addr_type_t type)
3942 {
3943 	struct net *net = sock_net(skb->sk);
3944 	int h, s_h;
3945 	int idx, ip_idx;
3946 	int s_idx, s_ip_idx;
3947 	struct net_device *dev;
3948 	struct inet6_dev *idev;
3949 	struct hlist_head *head;
3950 
3951 	s_h = cb->args[0];
3952 	s_idx = idx = cb->args[1];
3953 	s_ip_idx = ip_idx = cb->args[2];
3954 
3955 	rcu_read_lock();
3956 	cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^ net->dev_base_seq;
3957 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
3958 		idx = 0;
3959 		head = &net->dev_index_head[h];
3960 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
3961 			if (idx < s_idx)
3962 				goto cont;
3963 			if (h > s_h || idx > s_idx)
3964 				s_ip_idx = 0;
3965 			ip_idx = 0;
3966 			idev = __in6_dev_get(dev);
3967 			if (!idev)
3968 				goto cont;
3969 
3970 			if (in6_dump_addrs(idev, skb, cb, type,
3971 					   s_ip_idx, &ip_idx) <= 0)
3972 				goto done;
3973 cont:
3974 			idx++;
3975 		}
3976 	}
3977 done:
3978 	rcu_read_unlock();
3979 	cb->args[0] = h;
3980 	cb->args[1] = idx;
3981 	cb->args[2] = ip_idx;
3982 
3983 	return skb->len;
3984 }
3985 
3986 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
3987 {
3988 	enum addr_type_t type = UNICAST_ADDR;
3989 
3990 	return inet6_dump_addr(skb, cb, type);
3991 }
3992 
3993 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
3994 {
3995 	enum addr_type_t type = MULTICAST_ADDR;
3996 
3997 	return inet6_dump_addr(skb, cb, type);
3998 }
3999 
4000 
4001 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
4002 {
4003 	enum addr_type_t type = ANYCAST_ADDR;
4004 
4005 	return inet6_dump_addr(skb, cb, type);
4006 }
4007 
4008 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh)
4009 {
4010 	struct net *net = sock_net(in_skb->sk);
4011 	struct ifaddrmsg *ifm;
4012 	struct nlattr *tb[IFA_MAX+1];
4013 	struct in6_addr *addr = NULL;
4014 	struct net_device *dev = NULL;
4015 	struct inet6_ifaddr *ifa;
4016 	struct sk_buff *skb;
4017 	int err;
4018 
4019 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
4020 	if (err < 0)
4021 		goto errout;
4022 
4023 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL]);
4024 	if (addr == NULL) {
4025 		err = -EINVAL;
4026 		goto errout;
4027 	}
4028 
4029 	ifm = nlmsg_data(nlh);
4030 	if (ifm->ifa_index)
4031 		dev = __dev_get_by_index(net, ifm->ifa_index);
4032 
4033 	ifa = ipv6_get_ifaddr(net, addr, dev, 1);
4034 	if (!ifa) {
4035 		err = -EADDRNOTAVAIL;
4036 		goto errout;
4037 	}
4038 
4039 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
4040 	if (!skb) {
4041 		err = -ENOBUFS;
4042 		goto errout_ifa;
4043 	}
4044 
4045 	err = inet6_fill_ifaddr(skb, ifa, NETLINK_CB(in_skb).portid,
4046 				nlh->nlmsg_seq, RTM_NEWADDR, 0);
4047 	if (err < 0) {
4048 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
4049 		WARN_ON(err == -EMSGSIZE);
4050 		kfree_skb(skb);
4051 		goto errout_ifa;
4052 	}
4053 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
4054 errout_ifa:
4055 	in6_ifa_put(ifa);
4056 errout:
4057 	return err;
4058 }
4059 
4060 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
4061 {
4062 	struct sk_buff *skb;
4063 	struct net *net = dev_net(ifa->idev->dev);
4064 	int err = -ENOBUFS;
4065 
4066 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
4067 	if (skb == NULL)
4068 		goto errout;
4069 
4070 	err = inet6_fill_ifaddr(skb, ifa, 0, 0, event, 0);
4071 	if (err < 0) {
4072 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
4073 		WARN_ON(err == -EMSGSIZE);
4074 		kfree_skb(skb);
4075 		goto errout;
4076 	}
4077 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
4078 	return;
4079 errout:
4080 	if (err < 0)
4081 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
4082 }
4083 
4084 static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
4085 				__s32 *array, int bytes)
4086 {
4087 	BUG_ON(bytes < (DEVCONF_MAX * 4));
4088 
4089 	memset(array, 0, bytes);
4090 	array[DEVCONF_FORWARDING] = cnf->forwarding;
4091 	array[DEVCONF_HOPLIMIT] = cnf->hop_limit;
4092 	array[DEVCONF_MTU6] = cnf->mtu6;
4093 	array[DEVCONF_ACCEPT_RA] = cnf->accept_ra;
4094 	array[DEVCONF_ACCEPT_REDIRECTS] = cnf->accept_redirects;
4095 	array[DEVCONF_AUTOCONF] = cnf->autoconf;
4096 	array[DEVCONF_DAD_TRANSMITS] = cnf->dad_transmits;
4097 	array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
4098 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
4099 		jiffies_to_msecs(cnf->rtr_solicit_interval);
4100 	array[DEVCONF_RTR_SOLICIT_DELAY] =
4101 		jiffies_to_msecs(cnf->rtr_solicit_delay);
4102 	array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;
4103 #ifdef CONFIG_IPV6_PRIVACY
4104 	array[DEVCONF_USE_TEMPADDR] = cnf->use_tempaddr;
4105 	array[DEVCONF_TEMP_VALID_LFT] = cnf->temp_valid_lft;
4106 	array[DEVCONF_TEMP_PREFERED_LFT] = cnf->temp_prefered_lft;
4107 	array[DEVCONF_REGEN_MAX_RETRY] = cnf->regen_max_retry;
4108 	array[DEVCONF_MAX_DESYNC_FACTOR] = cnf->max_desync_factor;
4109 #endif
4110 	array[DEVCONF_MAX_ADDRESSES] = cnf->max_addresses;
4111 	array[DEVCONF_ACCEPT_RA_DEFRTR] = cnf->accept_ra_defrtr;
4112 	array[DEVCONF_ACCEPT_RA_PINFO] = cnf->accept_ra_pinfo;
4113 #ifdef CONFIG_IPV6_ROUTER_PREF
4114 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = cnf->accept_ra_rtr_pref;
4115 	array[DEVCONF_RTR_PROBE_INTERVAL] =
4116 		jiffies_to_msecs(cnf->rtr_probe_interval);
4117 #ifdef CONFIG_IPV6_ROUTE_INFO
4118 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
4119 #endif
4120 #endif
4121 	array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
4122 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
4123 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
4124 	array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
4125 #endif
4126 #ifdef CONFIG_IPV6_MROUTE
4127 	array[DEVCONF_MC_FORWARDING] = cnf->mc_forwarding;
4128 #endif
4129 	array[DEVCONF_DISABLE_IPV6] = cnf->disable_ipv6;
4130 	array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad;
4131 	array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao;
4132 	array[DEVCONF_NDISC_NOTIFY] = cnf->ndisc_notify;
4133 }
4134 
4135 static inline size_t inet6_ifla6_size(void)
4136 {
4137 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
4138 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
4139 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
4140 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
4141 	     + nla_total_size(ICMP6_MIB_MAX * 8); /* IFLA_INET6_ICMP6STATS */
4142 }
4143 
4144 static inline size_t inet6_if_nlmsg_size(void)
4145 {
4146 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
4147 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
4148 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
4149 	       + nla_total_size(4) /* IFLA_MTU */
4150 	       + nla_total_size(4) /* IFLA_LINK */
4151 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
4152 }
4153 
4154 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
4155 				      int items, int bytes)
4156 {
4157 	int i;
4158 	int pad = bytes - sizeof(u64) * items;
4159 	BUG_ON(pad < 0);
4160 
4161 	/* Use put_unaligned() because stats may not be aligned for u64. */
4162 	put_unaligned(items, &stats[0]);
4163 	for (i = 1; i < items; i++)
4164 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
4165 
4166 	memset(&stats[items], 0, pad);
4167 }
4168 
4169 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu **mib,
4170 				      int items, int bytes, size_t syncpoff)
4171 {
4172 	int i;
4173 	int pad = bytes - sizeof(u64) * items;
4174 	BUG_ON(pad < 0);
4175 
4176 	/* Use put_unaligned() because stats may not be aligned for u64. */
4177 	put_unaligned(items, &stats[0]);
4178 	for (i = 1; i < items; i++)
4179 		put_unaligned(snmp_fold_field64(mib, i, syncpoff), &stats[i]);
4180 
4181 	memset(&stats[items], 0, pad);
4182 }
4183 
4184 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
4185 			     int bytes)
4186 {
4187 	switch (attrtype) {
4188 	case IFLA_INET6_STATS:
4189 		__snmp6_fill_stats64(stats, (void __percpu **)idev->stats.ipv6,
4190 				     IPSTATS_MIB_MAX, bytes, offsetof(struct ipstats_mib, syncp));
4191 		break;
4192 	case IFLA_INET6_ICMP6STATS:
4193 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, ICMP6_MIB_MAX, bytes);
4194 		break;
4195 	}
4196 }
4197 
4198 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev)
4199 {
4200 	struct nlattr *nla;
4201 	struct ifla_cacheinfo ci;
4202 
4203 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, idev->if_flags))
4204 		goto nla_put_failure;
4205 	ci.max_reasm_len = IPV6_MAXPLEN;
4206 	ci.tstamp = cstamp_delta(idev->tstamp);
4207 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
4208 	ci.retrans_time = jiffies_to_msecs(idev->nd_parms->retrans_time);
4209 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
4210 		goto nla_put_failure;
4211 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
4212 	if (nla == NULL)
4213 		goto nla_put_failure;
4214 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
4215 
4216 	/* XXX - MC not implemented */
4217 
4218 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
4219 	if (nla == NULL)
4220 		goto nla_put_failure;
4221 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
4222 
4223 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
4224 	if (nla == NULL)
4225 		goto nla_put_failure;
4226 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
4227 
4228 	return 0;
4229 
4230 nla_put_failure:
4231 	return -EMSGSIZE;
4232 }
4233 
4234 static size_t inet6_get_link_af_size(const struct net_device *dev)
4235 {
4236 	if (!__in6_dev_get(dev))
4237 		return 0;
4238 
4239 	return inet6_ifla6_size();
4240 }
4241 
4242 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev)
4243 {
4244 	struct inet6_dev *idev = __in6_dev_get(dev);
4245 
4246 	if (!idev)
4247 		return -ENODATA;
4248 
4249 	if (inet6_fill_ifla6_attrs(skb, idev) < 0)
4250 		return -EMSGSIZE;
4251 
4252 	return 0;
4253 }
4254 
4255 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
4256 			     u32 portid, u32 seq, int event, unsigned int flags)
4257 {
4258 	struct net_device *dev = idev->dev;
4259 	struct ifinfomsg *hdr;
4260 	struct nlmsghdr *nlh;
4261 	void *protoinfo;
4262 
4263 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
4264 	if (nlh == NULL)
4265 		return -EMSGSIZE;
4266 
4267 	hdr = nlmsg_data(nlh);
4268 	hdr->ifi_family = AF_INET6;
4269 	hdr->__ifi_pad = 0;
4270 	hdr->ifi_type = dev->type;
4271 	hdr->ifi_index = dev->ifindex;
4272 	hdr->ifi_flags = dev_get_flags(dev);
4273 	hdr->ifi_change = 0;
4274 
4275 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
4276 	    (dev->addr_len &&
4277 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
4278 	    nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
4279 	    (dev->ifindex != dev->iflink &&
4280 	     nla_put_u32(skb, IFLA_LINK, dev->iflink)))
4281 		goto nla_put_failure;
4282 	protoinfo = nla_nest_start(skb, IFLA_PROTINFO);
4283 	if (protoinfo == NULL)
4284 		goto nla_put_failure;
4285 
4286 	if (inet6_fill_ifla6_attrs(skb, idev) < 0)
4287 		goto nla_put_failure;
4288 
4289 	nla_nest_end(skb, protoinfo);
4290 	return nlmsg_end(skb, nlh);
4291 
4292 nla_put_failure:
4293 	nlmsg_cancel(skb, nlh);
4294 	return -EMSGSIZE;
4295 }
4296 
4297 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
4298 {
4299 	struct net *net = sock_net(skb->sk);
4300 	int h, s_h;
4301 	int idx = 0, s_idx;
4302 	struct net_device *dev;
4303 	struct inet6_dev *idev;
4304 	struct hlist_head *head;
4305 
4306 	s_h = cb->args[0];
4307 	s_idx = cb->args[1];
4308 
4309 	rcu_read_lock();
4310 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
4311 		idx = 0;
4312 		head = &net->dev_index_head[h];
4313 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
4314 			if (idx < s_idx)
4315 				goto cont;
4316 			idev = __in6_dev_get(dev);
4317 			if (!idev)
4318 				goto cont;
4319 			if (inet6_fill_ifinfo(skb, idev,
4320 					      NETLINK_CB(cb->skb).portid,
4321 					      cb->nlh->nlmsg_seq,
4322 					      RTM_NEWLINK, NLM_F_MULTI) <= 0)
4323 				goto out;
4324 cont:
4325 			idx++;
4326 		}
4327 	}
4328 out:
4329 	rcu_read_unlock();
4330 	cb->args[1] = idx;
4331 	cb->args[0] = h;
4332 
4333 	return skb->len;
4334 }
4335 
4336 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
4337 {
4338 	struct sk_buff *skb;
4339 	struct net *net = dev_net(idev->dev);
4340 	int err = -ENOBUFS;
4341 
4342 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
4343 	if (skb == NULL)
4344 		goto errout;
4345 
4346 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
4347 	if (err < 0) {
4348 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
4349 		WARN_ON(err == -EMSGSIZE);
4350 		kfree_skb(skb);
4351 		goto errout;
4352 	}
4353 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
4354 	return;
4355 errout:
4356 	if (err < 0)
4357 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
4358 }
4359 
4360 static inline size_t inet6_prefix_nlmsg_size(void)
4361 {
4362 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
4363 	       + nla_total_size(sizeof(struct in6_addr))
4364 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
4365 }
4366 
4367 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
4368 			     struct prefix_info *pinfo, u32 portid, u32 seq,
4369 			     int event, unsigned int flags)
4370 {
4371 	struct prefixmsg *pmsg;
4372 	struct nlmsghdr *nlh;
4373 	struct prefix_cacheinfo	ci;
4374 
4375 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
4376 	if (nlh == NULL)
4377 		return -EMSGSIZE;
4378 
4379 	pmsg = nlmsg_data(nlh);
4380 	pmsg->prefix_family = AF_INET6;
4381 	pmsg->prefix_pad1 = 0;
4382 	pmsg->prefix_pad2 = 0;
4383 	pmsg->prefix_ifindex = idev->dev->ifindex;
4384 	pmsg->prefix_len = pinfo->prefix_len;
4385 	pmsg->prefix_type = pinfo->type;
4386 	pmsg->prefix_pad3 = 0;
4387 	pmsg->prefix_flags = 0;
4388 	if (pinfo->onlink)
4389 		pmsg->prefix_flags |= IF_PREFIX_ONLINK;
4390 	if (pinfo->autoconf)
4391 		pmsg->prefix_flags |= IF_PREFIX_AUTOCONF;
4392 
4393 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
4394 		goto nla_put_failure;
4395 	ci.preferred_time = ntohl(pinfo->prefered);
4396 	ci.valid_time = ntohl(pinfo->valid);
4397 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
4398 		goto nla_put_failure;
4399 	return nlmsg_end(skb, nlh);
4400 
4401 nla_put_failure:
4402 	nlmsg_cancel(skb, nlh);
4403 	return -EMSGSIZE;
4404 }
4405 
4406 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
4407 			 struct prefix_info *pinfo)
4408 {
4409 	struct sk_buff *skb;
4410 	struct net *net = dev_net(idev->dev);
4411 	int err = -ENOBUFS;
4412 
4413 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
4414 	if (skb == NULL)
4415 		goto errout;
4416 
4417 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
4418 	if (err < 0) {
4419 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
4420 		WARN_ON(err == -EMSGSIZE);
4421 		kfree_skb(skb);
4422 		goto errout;
4423 	}
4424 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
4425 	return;
4426 errout:
4427 	if (err < 0)
4428 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
4429 }
4430 
4431 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
4432 {
4433 	struct net *net = dev_net(ifp->idev->dev);
4434 
4435 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
4436 
4437 	switch (event) {
4438 	case RTM_NEWADDR:
4439 		/*
4440 		 * If the address was optimistic
4441 		 * we inserted the route at the start of
4442 		 * our DAD process, so we don't need
4443 		 * to do it again
4444 		 */
4445 		if (!(ifp->rt->rt6i_node))
4446 			ip6_ins_rt(ifp->rt);
4447 		if (ifp->idev->cnf.forwarding)
4448 			addrconf_join_anycast(ifp);
4449 		break;
4450 	case RTM_DELADDR:
4451 		if (ifp->idev->cnf.forwarding)
4452 			addrconf_leave_anycast(ifp);
4453 		addrconf_leave_solict(ifp->idev, &ifp->addr);
4454 		dst_hold(&ifp->rt->dst);
4455 
4456 		if (ip6_del_rt(ifp->rt))
4457 			dst_free(&ifp->rt->dst);
4458 		break;
4459 	}
4460 	atomic_inc(&net->ipv6.dev_addr_genid);
4461 }
4462 
4463 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
4464 {
4465 	rcu_read_lock_bh();
4466 	if (likely(ifp->idev->dead == 0))
4467 		__ipv6_ifa_notify(event, ifp);
4468 	rcu_read_unlock_bh();
4469 }
4470 
4471 #ifdef CONFIG_SYSCTL
4472 
4473 static
4474 int addrconf_sysctl_forward(ctl_table *ctl, int write,
4475 			   void __user *buffer, size_t *lenp, loff_t *ppos)
4476 {
4477 	int *valp = ctl->data;
4478 	int val = *valp;
4479 	loff_t pos = *ppos;
4480 	ctl_table lctl;
4481 	int ret;
4482 
4483 	/*
4484 	 * ctl->data points to idev->cnf.forwarding, we should
4485 	 * not modify it until we get the rtnl lock.
4486 	 */
4487 	lctl = *ctl;
4488 	lctl.data = &val;
4489 
4490 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
4491 
4492 	if (write)
4493 		ret = addrconf_fixup_forwarding(ctl, valp, val);
4494 	if (ret)
4495 		*ppos = pos;
4496 	return ret;
4497 }
4498 
4499 static void dev_disable_change(struct inet6_dev *idev)
4500 {
4501 	if (!idev || !idev->dev)
4502 		return;
4503 
4504 	if (idev->cnf.disable_ipv6)
4505 		addrconf_notify(NULL, NETDEV_DOWN, idev->dev);
4506 	else
4507 		addrconf_notify(NULL, NETDEV_UP, idev->dev);
4508 }
4509 
4510 static void addrconf_disable_change(struct net *net, __s32 newf)
4511 {
4512 	struct net_device *dev;
4513 	struct inet6_dev *idev;
4514 
4515 	rcu_read_lock();
4516 	for_each_netdev_rcu(net, dev) {
4517 		idev = __in6_dev_get(dev);
4518 		if (idev) {
4519 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
4520 			idev->cnf.disable_ipv6 = newf;
4521 			if (changed)
4522 				dev_disable_change(idev);
4523 		}
4524 	}
4525 	rcu_read_unlock();
4526 }
4527 
4528 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
4529 {
4530 	struct net *net;
4531 	int old;
4532 
4533 	if (!rtnl_trylock())
4534 		return restart_syscall();
4535 
4536 	net = (struct net *)table->extra2;
4537 	old = *p;
4538 	*p = newf;
4539 
4540 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
4541 		rtnl_unlock();
4542 		return 0;
4543 	}
4544 
4545 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
4546 		net->ipv6.devconf_dflt->disable_ipv6 = newf;
4547 		addrconf_disable_change(net, newf);
4548 	} else if ((!newf) ^ (!old))
4549 		dev_disable_change((struct inet6_dev *)table->extra1);
4550 
4551 	rtnl_unlock();
4552 	return 0;
4553 }
4554 
4555 static
4556 int addrconf_sysctl_disable(ctl_table *ctl, int write,
4557 			    void __user *buffer, size_t *lenp, loff_t *ppos)
4558 {
4559 	int *valp = ctl->data;
4560 	int val = *valp;
4561 	loff_t pos = *ppos;
4562 	ctl_table lctl;
4563 	int ret;
4564 
4565 	/*
4566 	 * ctl->data points to idev->cnf.disable_ipv6, we should
4567 	 * not modify it until we get the rtnl lock.
4568 	 */
4569 	lctl = *ctl;
4570 	lctl.data = &val;
4571 
4572 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
4573 
4574 	if (write)
4575 		ret = addrconf_disable_ipv6(ctl, valp, val);
4576 	if (ret)
4577 		*ppos = pos;
4578 	return ret;
4579 }
4580 
4581 static struct addrconf_sysctl_table
4582 {
4583 	struct ctl_table_header *sysctl_header;
4584 	ctl_table addrconf_vars[DEVCONF_MAX+1];
4585 } addrconf_sysctl __read_mostly = {
4586 	.sysctl_header = NULL,
4587 	.addrconf_vars = {
4588 		{
4589 			.procname	= "forwarding",
4590 			.data		= &ipv6_devconf.forwarding,
4591 			.maxlen		= sizeof(int),
4592 			.mode		= 0644,
4593 			.proc_handler	= addrconf_sysctl_forward,
4594 		},
4595 		{
4596 			.procname	= "hop_limit",
4597 			.data		= &ipv6_devconf.hop_limit,
4598 			.maxlen		= sizeof(int),
4599 			.mode		= 0644,
4600 			.proc_handler	= proc_dointvec,
4601 		},
4602 		{
4603 			.procname	= "mtu",
4604 			.data		= &ipv6_devconf.mtu6,
4605 			.maxlen		= sizeof(int),
4606 			.mode		= 0644,
4607 			.proc_handler	= proc_dointvec,
4608 		},
4609 		{
4610 			.procname	= "accept_ra",
4611 			.data		= &ipv6_devconf.accept_ra,
4612 			.maxlen		= sizeof(int),
4613 			.mode		= 0644,
4614 			.proc_handler	= proc_dointvec,
4615 		},
4616 		{
4617 			.procname	= "accept_redirects",
4618 			.data		= &ipv6_devconf.accept_redirects,
4619 			.maxlen		= sizeof(int),
4620 			.mode		= 0644,
4621 			.proc_handler	= proc_dointvec,
4622 		},
4623 		{
4624 			.procname	= "autoconf",
4625 			.data		= &ipv6_devconf.autoconf,
4626 			.maxlen		= sizeof(int),
4627 			.mode		= 0644,
4628 			.proc_handler	= proc_dointvec,
4629 		},
4630 		{
4631 			.procname	= "dad_transmits",
4632 			.data		= &ipv6_devconf.dad_transmits,
4633 			.maxlen		= sizeof(int),
4634 			.mode		= 0644,
4635 			.proc_handler	= proc_dointvec,
4636 		},
4637 		{
4638 			.procname	= "router_solicitations",
4639 			.data		= &ipv6_devconf.rtr_solicits,
4640 			.maxlen		= sizeof(int),
4641 			.mode		= 0644,
4642 			.proc_handler	= proc_dointvec,
4643 		},
4644 		{
4645 			.procname	= "router_solicitation_interval",
4646 			.data		= &ipv6_devconf.rtr_solicit_interval,
4647 			.maxlen		= sizeof(int),
4648 			.mode		= 0644,
4649 			.proc_handler	= proc_dointvec_jiffies,
4650 		},
4651 		{
4652 			.procname	= "router_solicitation_delay",
4653 			.data		= &ipv6_devconf.rtr_solicit_delay,
4654 			.maxlen		= sizeof(int),
4655 			.mode		= 0644,
4656 			.proc_handler	= proc_dointvec_jiffies,
4657 		},
4658 		{
4659 			.procname	= "force_mld_version",
4660 			.data		= &ipv6_devconf.force_mld_version,
4661 			.maxlen		= sizeof(int),
4662 			.mode		= 0644,
4663 			.proc_handler	= proc_dointvec,
4664 		},
4665 #ifdef CONFIG_IPV6_PRIVACY
4666 		{
4667 			.procname	= "use_tempaddr",
4668 			.data		= &ipv6_devconf.use_tempaddr,
4669 			.maxlen		= sizeof(int),
4670 			.mode		= 0644,
4671 			.proc_handler	= proc_dointvec,
4672 		},
4673 		{
4674 			.procname	= "temp_valid_lft",
4675 			.data		= &ipv6_devconf.temp_valid_lft,
4676 			.maxlen		= sizeof(int),
4677 			.mode		= 0644,
4678 			.proc_handler	= proc_dointvec,
4679 		},
4680 		{
4681 			.procname	= "temp_prefered_lft",
4682 			.data		= &ipv6_devconf.temp_prefered_lft,
4683 			.maxlen		= sizeof(int),
4684 			.mode		= 0644,
4685 			.proc_handler	= proc_dointvec,
4686 		},
4687 		{
4688 			.procname	= "regen_max_retry",
4689 			.data		= &ipv6_devconf.regen_max_retry,
4690 			.maxlen		= sizeof(int),
4691 			.mode		= 0644,
4692 			.proc_handler	= proc_dointvec,
4693 		},
4694 		{
4695 			.procname	= "max_desync_factor",
4696 			.data		= &ipv6_devconf.max_desync_factor,
4697 			.maxlen		= sizeof(int),
4698 			.mode		= 0644,
4699 			.proc_handler	= proc_dointvec,
4700 		},
4701 #endif
4702 		{
4703 			.procname	= "max_addresses",
4704 			.data		= &ipv6_devconf.max_addresses,
4705 			.maxlen		= sizeof(int),
4706 			.mode		= 0644,
4707 			.proc_handler	= proc_dointvec,
4708 		},
4709 		{
4710 			.procname	= "accept_ra_defrtr",
4711 			.data		= &ipv6_devconf.accept_ra_defrtr,
4712 			.maxlen		= sizeof(int),
4713 			.mode		= 0644,
4714 			.proc_handler	= proc_dointvec,
4715 		},
4716 		{
4717 			.procname	= "accept_ra_pinfo",
4718 			.data		= &ipv6_devconf.accept_ra_pinfo,
4719 			.maxlen		= sizeof(int),
4720 			.mode		= 0644,
4721 			.proc_handler	= proc_dointvec,
4722 		},
4723 #ifdef CONFIG_IPV6_ROUTER_PREF
4724 		{
4725 			.procname	= "accept_ra_rtr_pref",
4726 			.data		= &ipv6_devconf.accept_ra_rtr_pref,
4727 			.maxlen		= sizeof(int),
4728 			.mode		= 0644,
4729 			.proc_handler	= proc_dointvec,
4730 		},
4731 		{
4732 			.procname	= "router_probe_interval",
4733 			.data		= &ipv6_devconf.rtr_probe_interval,
4734 			.maxlen		= sizeof(int),
4735 			.mode		= 0644,
4736 			.proc_handler	= proc_dointvec_jiffies,
4737 		},
4738 #ifdef CONFIG_IPV6_ROUTE_INFO
4739 		{
4740 			.procname	= "accept_ra_rt_info_max_plen",
4741 			.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
4742 			.maxlen		= sizeof(int),
4743 			.mode		= 0644,
4744 			.proc_handler	= proc_dointvec,
4745 		},
4746 #endif
4747 #endif
4748 		{
4749 			.procname	= "proxy_ndp",
4750 			.data		= &ipv6_devconf.proxy_ndp,
4751 			.maxlen		= sizeof(int),
4752 			.mode		= 0644,
4753 			.proc_handler	= proc_dointvec,
4754 		},
4755 		{
4756 			.procname	= "accept_source_route",
4757 			.data		= &ipv6_devconf.accept_source_route,
4758 			.maxlen		= sizeof(int),
4759 			.mode		= 0644,
4760 			.proc_handler	= proc_dointvec,
4761 		},
4762 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
4763 		{
4764 			.procname       = "optimistic_dad",
4765 			.data           = &ipv6_devconf.optimistic_dad,
4766 			.maxlen         = sizeof(int),
4767 			.mode           = 0644,
4768 			.proc_handler   = proc_dointvec,
4769 
4770 		},
4771 #endif
4772 #ifdef CONFIG_IPV6_MROUTE
4773 		{
4774 			.procname	= "mc_forwarding",
4775 			.data		= &ipv6_devconf.mc_forwarding,
4776 			.maxlen		= sizeof(int),
4777 			.mode		= 0444,
4778 			.proc_handler	= proc_dointvec,
4779 		},
4780 #endif
4781 		{
4782 			.procname	= "disable_ipv6",
4783 			.data		= &ipv6_devconf.disable_ipv6,
4784 			.maxlen		= sizeof(int),
4785 			.mode		= 0644,
4786 			.proc_handler	= addrconf_sysctl_disable,
4787 		},
4788 		{
4789 			.procname	= "accept_dad",
4790 			.data		= &ipv6_devconf.accept_dad,
4791 			.maxlen		= sizeof(int),
4792 			.mode		= 0644,
4793 			.proc_handler	= proc_dointvec,
4794 		},
4795 		{
4796 			.procname       = "force_tllao",
4797 			.data           = &ipv6_devconf.force_tllao,
4798 			.maxlen         = sizeof(int),
4799 			.mode           = 0644,
4800 			.proc_handler   = proc_dointvec
4801 		},
4802 		{
4803 			.procname       = "ndisc_notify",
4804 			.data           = &ipv6_devconf.ndisc_notify,
4805 			.maxlen         = sizeof(int),
4806 			.mode           = 0644,
4807 			.proc_handler   = proc_dointvec
4808 		},
4809 		{
4810 			/* sentinel */
4811 		}
4812 	},
4813 };
4814 
4815 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
4816 		struct inet6_dev *idev, struct ipv6_devconf *p)
4817 {
4818 	int i;
4819 	struct addrconf_sysctl_table *t;
4820 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
4821 
4822 	t = kmemdup(&addrconf_sysctl, sizeof(*t), GFP_KERNEL);
4823 	if (t == NULL)
4824 		goto out;
4825 
4826 	for (i = 0; t->addrconf_vars[i].data; i++) {
4827 		t->addrconf_vars[i].data += (char *)p - (char *)&ipv6_devconf;
4828 		t->addrconf_vars[i].extra1 = idev; /* embedded; no ref */
4829 		t->addrconf_vars[i].extra2 = net;
4830 	}
4831 
4832 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
4833 
4834 	t->sysctl_header = register_net_sysctl(net, path, t->addrconf_vars);
4835 	if (t->sysctl_header == NULL)
4836 		goto free;
4837 
4838 	p->sysctl = t;
4839 	return 0;
4840 
4841 free:
4842 	kfree(t);
4843 out:
4844 	return -ENOBUFS;
4845 }
4846 
4847 static void __addrconf_sysctl_unregister(struct ipv6_devconf *p)
4848 {
4849 	struct addrconf_sysctl_table *t;
4850 
4851 	if (p->sysctl == NULL)
4852 		return;
4853 
4854 	t = p->sysctl;
4855 	p->sysctl = NULL;
4856 	unregister_net_sysctl_table(t->sysctl_header);
4857 	kfree(t);
4858 }
4859 
4860 static void addrconf_sysctl_register(struct inet6_dev *idev)
4861 {
4862 	neigh_sysctl_register(idev->dev, idev->nd_parms, "ipv6",
4863 			      &ndisc_ifinfo_sysctl_change);
4864 	__addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
4865 					idev, &idev->cnf);
4866 }
4867 
4868 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
4869 {
4870 	__addrconf_sysctl_unregister(&idev->cnf);
4871 	neigh_sysctl_unregister(idev->nd_parms);
4872 }
4873 
4874 
4875 #endif
4876 
4877 static int __net_init addrconf_init_net(struct net *net)
4878 {
4879 	int err = -ENOMEM;
4880 	struct ipv6_devconf *all, *dflt;
4881 
4882 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
4883 	if (all == NULL)
4884 		goto err_alloc_all;
4885 
4886 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
4887 	if (dflt == NULL)
4888 		goto err_alloc_dflt;
4889 
4890 	/* these will be inherited by all namespaces */
4891 	dflt->autoconf = ipv6_defaults.autoconf;
4892 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
4893 
4894 	net->ipv6.devconf_all = all;
4895 	net->ipv6.devconf_dflt = dflt;
4896 
4897 #ifdef CONFIG_SYSCTL
4898 	err = __addrconf_sysctl_register(net, "all", NULL, all);
4899 	if (err < 0)
4900 		goto err_reg_all;
4901 
4902 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
4903 	if (err < 0)
4904 		goto err_reg_dflt;
4905 #endif
4906 	return 0;
4907 
4908 #ifdef CONFIG_SYSCTL
4909 err_reg_dflt:
4910 	__addrconf_sysctl_unregister(all);
4911 err_reg_all:
4912 	kfree(dflt);
4913 #endif
4914 err_alloc_dflt:
4915 	kfree(all);
4916 err_alloc_all:
4917 	return err;
4918 }
4919 
4920 static void __net_exit addrconf_exit_net(struct net *net)
4921 {
4922 #ifdef CONFIG_SYSCTL
4923 	__addrconf_sysctl_unregister(net->ipv6.devconf_dflt);
4924 	__addrconf_sysctl_unregister(net->ipv6.devconf_all);
4925 #endif
4926 	if (!net_eq(net, &init_net)) {
4927 		kfree(net->ipv6.devconf_dflt);
4928 		kfree(net->ipv6.devconf_all);
4929 	}
4930 }
4931 
4932 static struct pernet_operations addrconf_ops = {
4933 	.init = addrconf_init_net,
4934 	.exit = addrconf_exit_net,
4935 };
4936 
4937 /*
4938  *      Device notifier
4939  */
4940 
4941 int register_inet6addr_notifier(struct notifier_block *nb)
4942 {
4943 	return atomic_notifier_chain_register(&inet6addr_chain, nb);
4944 }
4945 EXPORT_SYMBOL(register_inet6addr_notifier);
4946 
4947 int unregister_inet6addr_notifier(struct notifier_block *nb)
4948 {
4949 	return atomic_notifier_chain_unregister(&inet6addr_chain, nb);
4950 }
4951 EXPORT_SYMBOL(unregister_inet6addr_notifier);
4952 
4953 static struct rtnl_af_ops inet6_ops = {
4954 	.family		  = AF_INET6,
4955 	.fill_link_af	  = inet6_fill_link_af,
4956 	.get_link_af_size = inet6_get_link_af_size,
4957 };
4958 
4959 /*
4960  *	Init / cleanup code
4961  */
4962 
4963 int __init addrconf_init(void)
4964 {
4965 	int i, err;
4966 
4967 	err = ipv6_addr_label_init();
4968 	if (err < 0) {
4969 		pr_crit("%s: cannot initialize default policy table: %d\n",
4970 			__func__, err);
4971 		goto out;
4972 	}
4973 
4974 	err = register_pernet_subsys(&addrconf_ops);
4975 	if (err < 0)
4976 		goto out_addrlabel;
4977 
4978 	/* The addrconf netdev notifier requires that loopback_dev
4979 	 * has it's ipv6 private information allocated and setup
4980 	 * before it can bring up and give link-local addresses
4981 	 * to other devices which are up.
4982 	 *
4983 	 * Unfortunately, loopback_dev is not necessarily the first
4984 	 * entry in the global dev_base list of net devices.  In fact,
4985 	 * it is likely to be the very last entry on that list.
4986 	 * So this causes the notifier registry below to try and
4987 	 * give link-local addresses to all devices besides loopback_dev
4988 	 * first, then loopback_dev, which cases all the non-loopback_dev
4989 	 * devices to fail to get a link-local address.
4990 	 *
4991 	 * So, as a temporary fix, allocate the ipv6 structure for
4992 	 * loopback_dev first by hand.
4993 	 * Longer term, all of the dependencies ipv6 has upon the loopback
4994 	 * device and it being up should be removed.
4995 	 */
4996 	rtnl_lock();
4997 	if (!ipv6_add_dev(init_net.loopback_dev))
4998 		err = -ENOMEM;
4999 	rtnl_unlock();
5000 	if (err)
5001 		goto errlo;
5002 
5003 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
5004 		INIT_HLIST_HEAD(&inet6_addr_lst[i]);
5005 
5006 	register_netdevice_notifier(&ipv6_dev_notf);
5007 
5008 	addrconf_verify(0);
5009 
5010 	err = rtnl_af_register(&inet6_ops);
5011 	if (err < 0)
5012 		goto errout_af;
5013 
5014 	err = __rtnl_register(PF_INET6, RTM_GETLINK, NULL, inet6_dump_ifinfo,
5015 			      NULL);
5016 	if (err < 0)
5017 		goto errout;
5018 
5019 	/* Only the first call to __rtnl_register can fail */
5020 	__rtnl_register(PF_INET6, RTM_NEWADDR, inet6_rtm_newaddr, NULL, NULL);
5021 	__rtnl_register(PF_INET6, RTM_DELADDR, inet6_rtm_deladdr, NULL, NULL);
5022 	__rtnl_register(PF_INET6, RTM_GETADDR, inet6_rtm_getaddr,
5023 			inet6_dump_ifaddr, NULL);
5024 	__rtnl_register(PF_INET6, RTM_GETMULTICAST, NULL,
5025 			inet6_dump_ifmcaddr, NULL);
5026 	__rtnl_register(PF_INET6, RTM_GETANYCAST, NULL,
5027 			inet6_dump_ifacaddr, NULL);
5028 	__rtnl_register(PF_INET6, RTM_GETNETCONF, inet6_netconf_get_devconf,
5029 			inet6_netconf_dump_devconf, NULL);
5030 
5031 	ipv6_addr_label_rtnl_register();
5032 
5033 	return 0;
5034 errout:
5035 	rtnl_af_unregister(&inet6_ops);
5036 errout_af:
5037 	unregister_netdevice_notifier(&ipv6_dev_notf);
5038 errlo:
5039 	unregister_pernet_subsys(&addrconf_ops);
5040 out_addrlabel:
5041 	ipv6_addr_label_cleanup();
5042 out:
5043 	return err;
5044 }
5045 
5046 void addrconf_cleanup(void)
5047 {
5048 	struct net_device *dev;
5049 	int i;
5050 
5051 	unregister_netdevice_notifier(&ipv6_dev_notf);
5052 	unregister_pernet_subsys(&addrconf_ops);
5053 	ipv6_addr_label_cleanup();
5054 
5055 	rtnl_lock();
5056 
5057 	__rtnl_af_unregister(&inet6_ops);
5058 
5059 	/* clean dev list */
5060 	for_each_netdev(&init_net, dev) {
5061 		if (__in6_dev_get(dev) == NULL)
5062 			continue;
5063 		addrconf_ifdown(dev, 1);
5064 	}
5065 	addrconf_ifdown(init_net.loopback_dev, 2);
5066 
5067 	/*
5068 	 *	Check hash table.
5069 	 */
5070 	spin_lock_bh(&addrconf_hash_lock);
5071 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
5072 		WARN_ON(!hlist_empty(&inet6_addr_lst[i]));
5073 	spin_unlock_bh(&addrconf_hash_lock);
5074 
5075 	del_timer(&addr_chk_timer);
5076 	rtnl_unlock();
5077 }
5078