xref: /openbmc/linux/net/ipv6/addrconf.c (revision fe2c6338fd2c6f383c4d4164262f35c8f3708e1f)
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 struct ipv6_devconf ipv6_devconf __read_mostly = {
173 	.forwarding		= 0,
174 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
175 	.mtu6			= IPV6_MIN_MTU,
176 	.accept_ra		= 1,
177 	.accept_redirects	= 1,
178 	.autoconf		= 1,
179 	.force_mld_version	= 0,
180 	.dad_transmits		= 1,
181 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
182 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
183 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
184 #ifdef CONFIG_IPV6_PRIVACY
185 	.use_tempaddr 		= 0,
186 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
187 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
188 	.regen_max_retry	= REGEN_MAX_RETRY,
189 	.max_desync_factor	= MAX_DESYNC_FACTOR,
190 #endif
191 	.max_addresses		= IPV6_MAX_ADDRESSES,
192 	.accept_ra_defrtr	= 1,
193 	.accept_ra_pinfo	= 1,
194 #ifdef CONFIG_IPV6_ROUTER_PREF
195 	.accept_ra_rtr_pref	= 1,
196 	.rtr_probe_interval	= 60 * HZ,
197 #ifdef CONFIG_IPV6_ROUTE_INFO
198 	.accept_ra_rt_info_max_plen = 0,
199 #endif
200 #endif
201 	.proxy_ndp		= 0,
202 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
203 	.disable_ipv6		= 0,
204 	.accept_dad		= 1,
205 };
206 
207 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
208 	.forwarding		= 0,
209 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
210 	.mtu6			= IPV6_MIN_MTU,
211 	.accept_ra		= 1,
212 	.accept_redirects	= 1,
213 	.autoconf		= 1,
214 	.dad_transmits		= 1,
215 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
216 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
217 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
218 #ifdef CONFIG_IPV6_PRIVACY
219 	.use_tempaddr		= 0,
220 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
221 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
222 	.regen_max_retry	= REGEN_MAX_RETRY,
223 	.max_desync_factor	= MAX_DESYNC_FACTOR,
224 #endif
225 	.max_addresses		= IPV6_MAX_ADDRESSES,
226 	.accept_ra_defrtr	= 1,
227 	.accept_ra_pinfo	= 1,
228 #ifdef CONFIG_IPV6_ROUTER_PREF
229 	.accept_ra_rtr_pref	= 1,
230 	.rtr_probe_interval	= 60 * HZ,
231 #ifdef CONFIG_IPV6_ROUTE_INFO
232 	.accept_ra_rt_info_max_plen = 0,
233 #endif
234 #endif
235 	.proxy_ndp		= 0,
236 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
237 	.disable_ipv6		= 0,
238 	.accept_dad		= 1,
239 };
240 
241 /* IPv6 Wildcard Address and Loopback Address defined by RFC2553 */
242 const struct in6_addr in6addr_any = IN6ADDR_ANY_INIT;
243 const struct in6_addr in6addr_loopback = IN6ADDR_LOOPBACK_INIT;
244 const struct in6_addr in6addr_linklocal_allnodes = IN6ADDR_LINKLOCAL_ALLNODES_INIT;
245 const struct in6_addr in6addr_linklocal_allrouters = IN6ADDR_LINKLOCAL_ALLROUTERS_INIT;
246 const struct in6_addr in6addr_interfacelocal_allnodes = IN6ADDR_INTERFACELOCAL_ALLNODES_INIT;
247 const struct in6_addr in6addr_interfacelocal_allrouters = IN6ADDR_INTERFACELOCAL_ALLROUTERS_INIT;
248 const struct in6_addr in6addr_sitelocal_allrouters = IN6ADDR_SITELOCAL_ALLROUTERS_INIT;
249 
250 /* Check if a valid qdisc is available */
251 static inline bool addrconf_qdisc_ok(const struct net_device *dev)
252 {
253 	return !qdisc_tx_is_noop(dev);
254 }
255 
256 static void addrconf_del_timer(struct inet6_ifaddr *ifp)
257 {
258 	if (del_timer(&ifp->timer))
259 		__in6_ifa_put(ifp);
260 }
261 
262 enum addrconf_timer_t {
263 	AC_NONE,
264 	AC_DAD,
265 	AC_RS,
266 };
267 
268 static void addrconf_mod_timer(struct inet6_ifaddr *ifp,
269 			       enum addrconf_timer_t what,
270 			       unsigned long when)
271 {
272 	if (!del_timer(&ifp->timer))
273 		in6_ifa_hold(ifp);
274 
275 	switch (what) {
276 	case AC_DAD:
277 		ifp->timer.function = addrconf_dad_timer;
278 		break;
279 	case AC_RS:
280 		ifp->timer.function = addrconf_rs_timer;
281 		break;
282 	default:
283 		break;
284 	}
285 	ifp->timer.expires = jiffies + when;
286 	add_timer(&ifp->timer);
287 }
288 
289 static int snmp6_alloc_dev(struct inet6_dev *idev)
290 {
291 	if (snmp_mib_init((void __percpu **)idev->stats.ipv6,
292 			  sizeof(struct ipstats_mib),
293 			  __alignof__(struct ipstats_mib)) < 0)
294 		goto err_ip;
295 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
296 					GFP_KERNEL);
297 	if (!idev->stats.icmpv6dev)
298 		goto err_icmp;
299 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
300 					   GFP_KERNEL);
301 	if (!idev->stats.icmpv6msgdev)
302 		goto err_icmpmsg;
303 
304 	return 0;
305 
306 err_icmpmsg:
307 	kfree(idev->stats.icmpv6dev);
308 err_icmp:
309 	snmp_mib_free((void __percpu **)idev->stats.ipv6);
310 err_ip:
311 	return -ENOMEM;
312 }
313 
314 static void snmp6_free_dev(struct inet6_dev *idev)
315 {
316 	kfree(idev->stats.icmpv6msgdev);
317 	kfree(idev->stats.icmpv6dev);
318 	snmp_mib_free((void __percpu **)idev->stats.ipv6);
319 }
320 
321 /* Nobody refers to this device, we may destroy it. */
322 
323 void in6_dev_finish_destroy(struct inet6_dev *idev)
324 {
325 	struct net_device *dev = idev->dev;
326 
327 	WARN_ON(!list_empty(&idev->addr_list));
328 	WARN_ON(idev->mc_list != NULL);
329 
330 #ifdef NET_REFCNT_DEBUG
331 	pr_debug("%s: %s\n", __func__, dev ? dev->name : "NIL");
332 #endif
333 	dev_put(dev);
334 	if (!idev->dead) {
335 		pr_warn("Freeing alive inet6 device %p\n", idev);
336 		return;
337 	}
338 	snmp6_free_dev(idev);
339 	kfree_rcu(idev, rcu);
340 }
341 EXPORT_SYMBOL(in6_dev_finish_destroy);
342 
343 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
344 {
345 	struct inet6_dev *ndev;
346 
347 	ASSERT_RTNL();
348 
349 	if (dev->mtu < IPV6_MIN_MTU)
350 		return NULL;
351 
352 	ndev = kzalloc(sizeof(struct inet6_dev), GFP_KERNEL);
353 
354 	if (ndev == NULL)
355 		return NULL;
356 
357 	rwlock_init(&ndev->lock);
358 	ndev->dev = dev;
359 	INIT_LIST_HEAD(&ndev->addr_list);
360 
361 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
362 	ndev->cnf.mtu6 = dev->mtu;
363 	ndev->cnf.sysctl = NULL;
364 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
365 	if (ndev->nd_parms == NULL) {
366 		kfree(ndev);
367 		return NULL;
368 	}
369 	if (ndev->cnf.forwarding)
370 		dev_disable_lro(dev);
371 	/* We refer to the device */
372 	dev_hold(dev);
373 
374 	if (snmp6_alloc_dev(ndev) < 0) {
375 		ADBG((KERN_WARNING
376 			"%s: cannot allocate memory for statistics; dev=%s.\n",
377 			__func__, dev->name));
378 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
379 		dev_put(dev);
380 		kfree(ndev);
381 		return NULL;
382 	}
383 
384 	if (snmp6_register_dev(ndev) < 0) {
385 		ADBG((KERN_WARNING
386 			"%s: cannot create /proc/net/dev_snmp6/%s\n",
387 			__func__, dev->name));
388 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
389 		ndev->dead = 1;
390 		in6_dev_finish_destroy(ndev);
391 		return NULL;
392 	}
393 
394 	/* One reference from device.  We must do this before
395 	 * we invoke __ipv6_regen_rndid().
396 	 */
397 	in6_dev_hold(ndev);
398 
399 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
400 		ndev->cnf.accept_dad = -1;
401 
402 #if IS_ENABLED(CONFIG_IPV6_SIT)
403 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
404 		pr_info("%s: Disabled Multicast RS\n", dev->name);
405 		ndev->cnf.rtr_solicits = 0;
406 	}
407 #endif
408 
409 #ifdef CONFIG_IPV6_PRIVACY
410 	INIT_LIST_HEAD(&ndev->tempaddr_list);
411 	setup_timer(&ndev->regen_timer, ipv6_regen_rndid, (unsigned long)ndev);
412 	if ((dev->flags&IFF_LOOPBACK) ||
413 	    dev->type == ARPHRD_TUNNEL ||
414 	    dev->type == ARPHRD_TUNNEL6 ||
415 	    dev->type == ARPHRD_SIT ||
416 	    dev->type == ARPHRD_NONE) {
417 		ndev->cnf.use_tempaddr = -1;
418 	} else {
419 		in6_dev_hold(ndev);
420 		ipv6_regen_rndid((unsigned long) ndev);
421 	}
422 #endif
423 	ndev->token = in6addr_any;
424 
425 	if (netif_running(dev) && addrconf_qdisc_ok(dev))
426 		ndev->if_flags |= IF_READY;
427 
428 	ipv6_mc_init_dev(ndev);
429 	ndev->tstamp = jiffies;
430 	addrconf_sysctl_register(ndev);
431 	/* protected by rtnl_lock */
432 	rcu_assign_pointer(dev->ip6_ptr, ndev);
433 
434 	/* Join interface-local all-node multicast group */
435 	ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes);
436 
437 	/* Join all-node multicast group */
438 	ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
439 
440 	/* Join all-router multicast group if forwarding is set */
441 	if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
442 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
443 
444 	return ndev;
445 }
446 
447 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
448 {
449 	struct inet6_dev *idev;
450 
451 	ASSERT_RTNL();
452 
453 	idev = __in6_dev_get(dev);
454 	if (!idev) {
455 		idev = ipv6_add_dev(dev);
456 		if (!idev)
457 			return NULL;
458 	}
459 
460 	if (dev->flags&IFF_UP)
461 		ipv6_mc_up(idev);
462 	return idev;
463 }
464 
465 static int inet6_netconf_msgsize_devconf(int type)
466 {
467 	int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
468 		    + nla_total_size(4);	/* NETCONFA_IFINDEX */
469 
470 	/* type -1 is used for ALL */
471 	if (type == -1 || type == NETCONFA_FORWARDING)
472 		size += nla_total_size(4);
473 #ifdef CONFIG_IPV6_MROUTE
474 	if (type == -1 || type == NETCONFA_MC_FORWARDING)
475 		size += nla_total_size(4);
476 #endif
477 
478 	return size;
479 }
480 
481 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
482 				      struct ipv6_devconf *devconf, u32 portid,
483 				      u32 seq, int event, unsigned int flags,
484 				      int type)
485 {
486 	struct nlmsghdr  *nlh;
487 	struct netconfmsg *ncm;
488 
489 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
490 			flags);
491 	if (nlh == NULL)
492 		return -EMSGSIZE;
493 
494 	ncm = nlmsg_data(nlh);
495 	ncm->ncm_family = AF_INET6;
496 
497 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
498 		goto nla_put_failure;
499 
500 	/* type -1 is used for ALL */
501 	if ((type == -1 || type == NETCONFA_FORWARDING) &&
502 	    nla_put_s32(skb, NETCONFA_FORWARDING, devconf->forwarding) < 0)
503 		goto nla_put_failure;
504 #ifdef CONFIG_IPV6_MROUTE
505 	if ((type == -1 || type == NETCONFA_MC_FORWARDING) &&
506 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
507 			devconf->mc_forwarding) < 0)
508 		goto nla_put_failure;
509 #endif
510 	return nlmsg_end(skb, nlh);
511 
512 nla_put_failure:
513 	nlmsg_cancel(skb, nlh);
514 	return -EMSGSIZE;
515 }
516 
517 void inet6_netconf_notify_devconf(struct net *net, int type, int ifindex,
518 				  struct ipv6_devconf *devconf)
519 {
520 	struct sk_buff *skb;
521 	int err = -ENOBUFS;
522 
523 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_ATOMIC);
524 	if (skb == NULL)
525 		goto errout;
526 
527 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
528 					 RTM_NEWNETCONF, 0, type);
529 	if (err < 0) {
530 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
531 		WARN_ON(err == -EMSGSIZE);
532 		kfree_skb(skb);
533 		goto errout;
534 	}
535 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_ATOMIC);
536 	return;
537 errout:
538 	rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
539 }
540 
541 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
542 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
543 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
544 };
545 
546 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
547 				     struct nlmsghdr *nlh)
548 {
549 	struct net *net = sock_net(in_skb->sk);
550 	struct nlattr *tb[NETCONFA_MAX+1];
551 	struct netconfmsg *ncm;
552 	struct sk_buff *skb;
553 	struct ipv6_devconf *devconf;
554 	struct inet6_dev *in6_dev;
555 	struct net_device *dev;
556 	int ifindex;
557 	int err;
558 
559 	err = nlmsg_parse(nlh, sizeof(*ncm), tb, NETCONFA_MAX,
560 			  devconf_ipv6_policy);
561 	if (err < 0)
562 		goto errout;
563 
564 	err = EINVAL;
565 	if (!tb[NETCONFA_IFINDEX])
566 		goto errout;
567 
568 	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
569 	switch (ifindex) {
570 	case NETCONFA_IFINDEX_ALL:
571 		devconf = net->ipv6.devconf_all;
572 		break;
573 	case NETCONFA_IFINDEX_DEFAULT:
574 		devconf = net->ipv6.devconf_dflt;
575 		break;
576 	default:
577 		dev = __dev_get_by_index(net, ifindex);
578 		if (dev == NULL)
579 			goto errout;
580 		in6_dev = __in6_dev_get(dev);
581 		if (in6_dev == NULL)
582 			goto errout;
583 		devconf = &in6_dev->cnf;
584 		break;
585 	}
586 
587 	err = -ENOBUFS;
588 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(-1), GFP_ATOMIC);
589 	if (skb == NULL)
590 		goto errout;
591 
592 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
593 					 NETLINK_CB(in_skb).portid,
594 					 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
595 					 -1);
596 	if (err < 0) {
597 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
598 		WARN_ON(err == -EMSGSIZE);
599 		kfree_skb(skb);
600 		goto errout;
601 	}
602 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
603 errout:
604 	return err;
605 }
606 
607 static int inet6_netconf_dump_devconf(struct sk_buff *skb,
608 				      struct netlink_callback *cb)
609 {
610 	struct net *net = sock_net(skb->sk);
611 	int h, s_h;
612 	int idx, s_idx;
613 	struct net_device *dev;
614 	struct inet6_dev *idev;
615 	struct hlist_head *head;
616 
617 	s_h = cb->args[0];
618 	s_idx = idx = cb->args[1];
619 
620 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
621 		idx = 0;
622 		head = &net->dev_index_head[h];
623 		rcu_read_lock();
624 		cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^
625 			  net->dev_base_seq;
626 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
627 			if (idx < s_idx)
628 				goto cont;
629 			idev = __in6_dev_get(dev);
630 			if (!idev)
631 				goto cont;
632 
633 			if (inet6_netconf_fill_devconf(skb, dev->ifindex,
634 						       &idev->cnf,
635 						       NETLINK_CB(cb->skb).portid,
636 						       cb->nlh->nlmsg_seq,
637 						       RTM_NEWNETCONF,
638 						       NLM_F_MULTI,
639 						       -1) <= 0) {
640 				rcu_read_unlock();
641 				goto done;
642 			}
643 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
644 cont:
645 			idx++;
646 		}
647 		rcu_read_unlock();
648 	}
649 	if (h == NETDEV_HASHENTRIES) {
650 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
651 					       net->ipv6.devconf_all,
652 					       NETLINK_CB(cb->skb).portid,
653 					       cb->nlh->nlmsg_seq,
654 					       RTM_NEWNETCONF, NLM_F_MULTI,
655 					       -1) <= 0)
656 			goto done;
657 		else
658 			h++;
659 	}
660 	if (h == NETDEV_HASHENTRIES + 1) {
661 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
662 					       net->ipv6.devconf_dflt,
663 					       NETLINK_CB(cb->skb).portid,
664 					       cb->nlh->nlmsg_seq,
665 					       RTM_NEWNETCONF, NLM_F_MULTI,
666 					       -1) <= 0)
667 			goto done;
668 		else
669 			h++;
670 	}
671 done:
672 	cb->args[0] = h;
673 	cb->args[1] = idx;
674 
675 	return skb->len;
676 }
677 
678 #ifdef CONFIG_SYSCTL
679 static void dev_forward_change(struct inet6_dev *idev)
680 {
681 	struct net_device *dev;
682 	struct inet6_ifaddr *ifa;
683 
684 	if (!idev)
685 		return;
686 	dev = idev->dev;
687 	if (idev->cnf.forwarding)
688 		dev_disable_lro(dev);
689 	if (dev->flags & IFF_MULTICAST) {
690 		if (idev->cnf.forwarding) {
691 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
692 			ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
693 			ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters);
694 		} else {
695 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
696 			ipv6_dev_mc_dec(dev, &in6addr_interfacelocal_allrouters);
697 			ipv6_dev_mc_dec(dev, &in6addr_sitelocal_allrouters);
698 		}
699 	}
700 
701 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
702 		if (ifa->flags&IFA_F_TENTATIVE)
703 			continue;
704 		if (idev->cnf.forwarding)
705 			addrconf_join_anycast(ifa);
706 		else
707 			addrconf_leave_anycast(ifa);
708 	}
709 	inet6_netconf_notify_devconf(dev_net(dev), NETCONFA_FORWARDING,
710 				     dev->ifindex, &idev->cnf);
711 }
712 
713 
714 static void addrconf_forward_change(struct net *net, __s32 newf)
715 {
716 	struct net_device *dev;
717 	struct inet6_dev *idev;
718 
719 	for_each_netdev(net, dev) {
720 		idev = __in6_dev_get(dev);
721 		if (idev) {
722 			int changed = (!idev->cnf.forwarding) ^ (!newf);
723 			idev->cnf.forwarding = newf;
724 			if (changed)
725 				dev_forward_change(idev);
726 		}
727 	}
728 }
729 
730 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int newf)
731 {
732 	struct net *net;
733 	int old;
734 
735 	if (!rtnl_trylock())
736 		return restart_syscall();
737 
738 	net = (struct net *)table->extra2;
739 	old = *p;
740 	*p = newf;
741 
742 	if (p == &net->ipv6.devconf_dflt->forwarding) {
743 		if ((!newf) ^ (!old))
744 			inet6_netconf_notify_devconf(net, NETCONFA_FORWARDING,
745 						     NETCONFA_IFINDEX_DEFAULT,
746 						     net->ipv6.devconf_dflt);
747 		rtnl_unlock();
748 		return 0;
749 	}
750 
751 	if (p == &net->ipv6.devconf_all->forwarding) {
752 		net->ipv6.devconf_dflt->forwarding = newf;
753 		addrconf_forward_change(net, newf);
754 		if ((!newf) ^ (!old))
755 			inet6_netconf_notify_devconf(net, NETCONFA_FORWARDING,
756 						     NETCONFA_IFINDEX_ALL,
757 						     net->ipv6.devconf_all);
758 	} else if ((!newf) ^ (!old))
759 		dev_forward_change((struct inet6_dev *)table->extra1);
760 	rtnl_unlock();
761 
762 	if (newf)
763 		rt6_purge_dflt_routers(net);
764 	return 1;
765 }
766 #endif
767 
768 /* Nobody refers to this ifaddr, destroy it */
769 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
770 {
771 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
772 
773 #ifdef NET_REFCNT_DEBUG
774 	pr_debug("%s\n", __func__);
775 #endif
776 
777 	in6_dev_put(ifp->idev);
778 
779 	if (del_timer(&ifp->timer))
780 		pr_notice("Timer is still running, when freeing ifa=%p\n", ifp);
781 
782 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
783 		pr_warn("Freeing alive inet6 address %p\n", ifp);
784 		return;
785 	}
786 	ip6_rt_put(ifp->rt);
787 
788 	kfree_rcu(ifp, rcu);
789 }
790 
791 static void
792 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
793 {
794 	struct list_head *p;
795 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
796 
797 	/*
798 	 * Each device address list is sorted in order of scope -
799 	 * global before linklocal.
800 	 */
801 	list_for_each(p, &idev->addr_list) {
802 		struct inet6_ifaddr *ifa
803 			= list_entry(p, struct inet6_ifaddr, if_list);
804 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
805 			break;
806 	}
807 
808 	list_add_tail(&ifp->if_list, p);
809 }
810 
811 static u32 inet6_addr_hash(const struct in6_addr *addr)
812 {
813 	return hash_32(ipv6_addr_hash(addr), IN6_ADDR_HSIZE_SHIFT);
814 }
815 
816 /* On success it returns ifp with increased reference count */
817 
818 static struct inet6_ifaddr *
819 ipv6_add_addr(struct inet6_dev *idev, const struct in6_addr *addr, int pfxlen,
820 	      int scope, u32 flags)
821 {
822 	struct inet6_ifaddr *ifa = NULL;
823 	struct rt6_info *rt;
824 	unsigned int hash;
825 	int err = 0;
826 	int addr_type = ipv6_addr_type(addr);
827 
828 	if (addr_type == IPV6_ADDR_ANY ||
829 	    addr_type & IPV6_ADDR_MULTICAST ||
830 	    (!(idev->dev->flags & IFF_LOOPBACK) &&
831 	     addr_type & IPV6_ADDR_LOOPBACK))
832 		return ERR_PTR(-EADDRNOTAVAIL);
833 
834 	rcu_read_lock_bh();
835 	if (idev->dead) {
836 		err = -ENODEV;			/*XXX*/
837 		goto out2;
838 	}
839 
840 	if (idev->cnf.disable_ipv6) {
841 		err = -EACCES;
842 		goto out2;
843 	}
844 
845 	spin_lock(&addrconf_hash_lock);
846 
847 	/* Ignore adding duplicate addresses on an interface */
848 	if (ipv6_chk_same_addr(dev_net(idev->dev), addr, idev->dev)) {
849 		ADBG(("ipv6_add_addr: already assigned\n"));
850 		err = -EEXIST;
851 		goto out;
852 	}
853 
854 	ifa = kzalloc(sizeof(struct inet6_ifaddr), GFP_ATOMIC);
855 
856 	if (ifa == NULL) {
857 		ADBG(("ipv6_add_addr: malloc failed\n"));
858 		err = -ENOBUFS;
859 		goto out;
860 	}
861 
862 	rt = addrconf_dst_alloc(idev, addr, false);
863 	if (IS_ERR(rt)) {
864 		err = PTR_ERR(rt);
865 		goto out;
866 	}
867 
868 	ifa->addr = *addr;
869 
870 	spin_lock_init(&ifa->lock);
871 	spin_lock_init(&ifa->state_lock);
872 	init_timer(&ifa->timer);
873 	INIT_HLIST_NODE(&ifa->addr_lst);
874 	ifa->timer.data = (unsigned long) ifa;
875 	ifa->scope = scope;
876 	ifa->prefix_len = pfxlen;
877 	ifa->flags = flags | IFA_F_TENTATIVE;
878 	ifa->cstamp = ifa->tstamp = jiffies;
879 	ifa->tokenized = false;
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 		inet6addr_notifier_call_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 	inet6addr_notifier_call_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, ipv6_addr_scope(&addr),
1130 			      addr_flags) : NULL;
1131 	if (IS_ERR_OR_NULL(ift)) {
1132 		in6_ifa_put(ifp);
1133 		in6_dev_put(idev);
1134 		pr_info("%s: retry temporary address regeneration\n", __func__);
1135 		tmpaddr = &addr;
1136 		write_lock(&idev->lock);
1137 		goto retry;
1138 	}
1139 
1140 	spin_lock_bh(&ift->lock);
1141 	ift->ifpub = ifp;
1142 	ift->valid_lft = tmp_valid_lft;
1143 	ift->prefered_lft = tmp_prefered_lft;
1144 	ift->cstamp = now;
1145 	ift->tstamp = tmp_tstamp;
1146 	spin_unlock_bh(&ift->lock);
1147 
1148 	addrconf_dad_start(ift);
1149 	in6_ifa_put(ift);
1150 	in6_dev_put(idev);
1151 out:
1152 	return ret;
1153 }
1154 #endif
1155 
1156 /*
1157  *	Choose an appropriate source address (RFC3484)
1158  */
1159 enum {
1160 	IPV6_SADDR_RULE_INIT = 0,
1161 	IPV6_SADDR_RULE_LOCAL,
1162 	IPV6_SADDR_RULE_SCOPE,
1163 	IPV6_SADDR_RULE_PREFERRED,
1164 #ifdef CONFIG_IPV6_MIP6
1165 	IPV6_SADDR_RULE_HOA,
1166 #endif
1167 	IPV6_SADDR_RULE_OIF,
1168 	IPV6_SADDR_RULE_LABEL,
1169 #ifdef CONFIG_IPV6_PRIVACY
1170 	IPV6_SADDR_RULE_PRIVACY,
1171 #endif
1172 	IPV6_SADDR_RULE_ORCHID,
1173 	IPV6_SADDR_RULE_PREFIX,
1174 	IPV6_SADDR_RULE_MAX
1175 };
1176 
1177 struct ipv6_saddr_score {
1178 	int			rule;
1179 	int			addr_type;
1180 	struct inet6_ifaddr	*ifa;
1181 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1182 	int			scopedist;
1183 	int			matchlen;
1184 };
1185 
1186 struct ipv6_saddr_dst {
1187 	const struct in6_addr *addr;
1188 	int ifindex;
1189 	int scope;
1190 	int label;
1191 	unsigned int prefs;
1192 };
1193 
1194 static inline int ipv6_saddr_preferred(int type)
1195 {
1196 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1197 		return 1;
1198 	return 0;
1199 }
1200 
1201 static int ipv6_get_saddr_eval(struct net *net,
1202 			       struct ipv6_saddr_score *score,
1203 			       struct ipv6_saddr_dst *dst,
1204 			       int i)
1205 {
1206 	int ret;
1207 
1208 	if (i <= score->rule) {
1209 		switch (i) {
1210 		case IPV6_SADDR_RULE_SCOPE:
1211 			ret = score->scopedist;
1212 			break;
1213 		case IPV6_SADDR_RULE_PREFIX:
1214 			ret = score->matchlen;
1215 			break;
1216 		default:
1217 			ret = !!test_bit(i, score->scorebits);
1218 		}
1219 		goto out;
1220 	}
1221 
1222 	switch (i) {
1223 	case IPV6_SADDR_RULE_INIT:
1224 		/* Rule 0: remember if hiscore is not ready yet */
1225 		ret = !!score->ifa;
1226 		break;
1227 	case IPV6_SADDR_RULE_LOCAL:
1228 		/* Rule 1: Prefer same address */
1229 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1230 		break;
1231 	case IPV6_SADDR_RULE_SCOPE:
1232 		/* Rule 2: Prefer appropriate scope
1233 		 *
1234 		 *      ret
1235 		 *       ^
1236 		 *    -1 |  d 15
1237 		 *    ---+--+-+---> scope
1238 		 *       |
1239 		 *       |             d is scope of the destination.
1240 		 *  B-d  |  \
1241 		 *       |   \      <- smaller scope is better if
1242 		 *  B-15 |    \        if scope is enough for destinaion.
1243 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1244 		 * d-C-1 | /
1245 		 *       |/         <- greater is better
1246 		 *   -C  /             if scope is not enough for destination.
1247 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1248 		 *
1249 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1250 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1251 		 * Assume B = 0 and we get C > 29.
1252 		 */
1253 		ret = __ipv6_addr_src_scope(score->addr_type);
1254 		if (ret >= dst->scope)
1255 			ret = -ret;
1256 		else
1257 			ret -= 128;	/* 30 is enough */
1258 		score->scopedist = ret;
1259 		break;
1260 	case IPV6_SADDR_RULE_PREFERRED:
1261 		/* Rule 3: Avoid deprecated and optimistic addresses */
1262 		ret = ipv6_saddr_preferred(score->addr_type) ||
1263 		      !(score->ifa->flags & (IFA_F_DEPRECATED|IFA_F_OPTIMISTIC));
1264 		break;
1265 #ifdef CONFIG_IPV6_MIP6
1266 	case IPV6_SADDR_RULE_HOA:
1267 	    {
1268 		/* Rule 4: Prefer home address */
1269 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1270 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1271 		break;
1272 	    }
1273 #endif
1274 	case IPV6_SADDR_RULE_OIF:
1275 		/* Rule 5: Prefer outgoing interface */
1276 		ret = (!dst->ifindex ||
1277 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1278 		break;
1279 	case IPV6_SADDR_RULE_LABEL:
1280 		/* Rule 6: Prefer matching label */
1281 		ret = ipv6_addr_label(net,
1282 				      &score->ifa->addr, score->addr_type,
1283 				      score->ifa->idev->dev->ifindex) == dst->label;
1284 		break;
1285 #ifdef CONFIG_IPV6_PRIVACY
1286 	case IPV6_SADDR_RULE_PRIVACY:
1287 	    {
1288 		/* Rule 7: Prefer public address
1289 		 * Note: prefer temporary address if use_tempaddr >= 2
1290 		 */
1291 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1292 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1293 				score->ifa->idev->cnf.use_tempaddr >= 2;
1294 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1295 		break;
1296 	    }
1297 #endif
1298 	case IPV6_SADDR_RULE_ORCHID:
1299 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1300 		 *	    non-ORCHID vs non-ORCHID
1301 		 */
1302 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1303 			ipv6_addr_orchid(dst->addr));
1304 		break;
1305 	case IPV6_SADDR_RULE_PREFIX:
1306 		/* Rule 8: Use longest matching prefix */
1307 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1308 		if (ret > score->ifa->prefix_len)
1309 			ret = score->ifa->prefix_len;
1310 		score->matchlen = ret;
1311 		break;
1312 	default:
1313 		ret = 0;
1314 	}
1315 
1316 	if (ret)
1317 		__set_bit(i, score->scorebits);
1318 	score->rule = i;
1319 out:
1320 	return ret;
1321 }
1322 
1323 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1324 		       const struct in6_addr *daddr, unsigned int prefs,
1325 		       struct in6_addr *saddr)
1326 {
1327 	struct ipv6_saddr_score scores[2],
1328 				*score = &scores[0], *hiscore = &scores[1];
1329 	struct ipv6_saddr_dst dst;
1330 	struct net_device *dev;
1331 	int dst_type;
1332 
1333 	dst_type = __ipv6_addr_type(daddr);
1334 	dst.addr = daddr;
1335 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1336 	dst.scope = __ipv6_addr_src_scope(dst_type);
1337 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1338 	dst.prefs = prefs;
1339 
1340 	hiscore->rule = -1;
1341 	hiscore->ifa = NULL;
1342 
1343 	rcu_read_lock();
1344 
1345 	for_each_netdev_rcu(net, dev) {
1346 		struct inet6_dev *idev;
1347 
1348 		/* Candidate Source Address (section 4)
1349 		 *  - multicast and link-local destination address,
1350 		 *    the set of candidate source address MUST only
1351 		 *    include addresses assigned to interfaces
1352 		 *    belonging to the same link as the outgoing
1353 		 *    interface.
1354 		 * (- For site-local destination addresses, the
1355 		 *    set of candidate source addresses MUST only
1356 		 *    include addresses assigned to interfaces
1357 		 *    belonging to the same site as the outgoing
1358 		 *    interface.)
1359 		 */
1360 		if (((dst_type & IPV6_ADDR_MULTICAST) ||
1361 		     dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL) &&
1362 		    dst.ifindex && dev->ifindex != dst.ifindex)
1363 			continue;
1364 
1365 		idev = __in6_dev_get(dev);
1366 		if (!idev)
1367 			continue;
1368 
1369 		read_lock_bh(&idev->lock);
1370 		list_for_each_entry(score->ifa, &idev->addr_list, if_list) {
1371 			int i;
1372 
1373 			/*
1374 			 * - Tentative Address (RFC2462 section 5.4)
1375 			 *  - A tentative address is not considered
1376 			 *    "assigned to an interface" in the traditional
1377 			 *    sense, unless it is also flagged as optimistic.
1378 			 * - Candidate Source Address (section 4)
1379 			 *  - In any case, anycast addresses, multicast
1380 			 *    addresses, and the unspecified address MUST
1381 			 *    NOT be included in a candidate set.
1382 			 */
1383 			if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1384 			    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1385 				continue;
1386 
1387 			score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1388 
1389 			if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1390 				     score->addr_type & IPV6_ADDR_MULTICAST)) {
1391 				LIMIT_NETDEBUG(KERN_DEBUG
1392 					       "ADDRCONF: unspecified / multicast address "
1393 					       "assigned as unicast address on %s",
1394 					       dev->name);
1395 				continue;
1396 			}
1397 
1398 			score->rule = -1;
1399 			bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1400 
1401 			for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1402 				int minihiscore, miniscore;
1403 
1404 				minihiscore = ipv6_get_saddr_eval(net, hiscore, &dst, i);
1405 				miniscore = ipv6_get_saddr_eval(net, score, &dst, i);
1406 
1407 				if (minihiscore > miniscore) {
1408 					if (i == IPV6_SADDR_RULE_SCOPE &&
1409 					    score->scopedist > 0) {
1410 						/*
1411 						 * special case:
1412 						 * each remaining entry
1413 						 * has too small (not enough)
1414 						 * scope, because ifa entries
1415 						 * are sorted by their scope
1416 						 * values.
1417 						 */
1418 						goto try_nextdev;
1419 					}
1420 					break;
1421 				} else if (minihiscore < miniscore) {
1422 					if (hiscore->ifa)
1423 						in6_ifa_put(hiscore->ifa);
1424 
1425 					in6_ifa_hold(score->ifa);
1426 
1427 					swap(hiscore, score);
1428 
1429 					/* restore our iterator */
1430 					score->ifa = hiscore->ifa;
1431 
1432 					break;
1433 				}
1434 			}
1435 		}
1436 try_nextdev:
1437 		read_unlock_bh(&idev->lock);
1438 	}
1439 	rcu_read_unlock();
1440 
1441 	if (!hiscore->ifa)
1442 		return -EADDRNOTAVAIL;
1443 
1444 	*saddr = hiscore->ifa->addr;
1445 	in6_ifa_put(hiscore->ifa);
1446 	return 0;
1447 }
1448 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1449 
1450 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1451 		    unsigned char banned_flags)
1452 {
1453 	struct inet6_dev *idev;
1454 	int err = -EADDRNOTAVAIL;
1455 
1456 	rcu_read_lock();
1457 	idev = __in6_dev_get(dev);
1458 	if (idev) {
1459 		struct inet6_ifaddr *ifp;
1460 
1461 		read_lock_bh(&idev->lock);
1462 		list_for_each_entry(ifp, &idev->addr_list, if_list) {
1463 			if (ifp->scope == IFA_LINK &&
1464 			    !(ifp->flags & banned_flags)) {
1465 				*addr = ifp->addr;
1466 				err = 0;
1467 				break;
1468 			}
1469 		}
1470 		read_unlock_bh(&idev->lock);
1471 	}
1472 	rcu_read_unlock();
1473 	return err;
1474 }
1475 
1476 static int ipv6_count_addresses(struct inet6_dev *idev)
1477 {
1478 	int cnt = 0;
1479 	struct inet6_ifaddr *ifp;
1480 
1481 	read_lock_bh(&idev->lock);
1482 	list_for_each_entry(ifp, &idev->addr_list, if_list)
1483 		cnt++;
1484 	read_unlock_bh(&idev->lock);
1485 	return cnt;
1486 }
1487 
1488 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1489 		  const struct net_device *dev, int strict)
1490 {
1491 	struct inet6_ifaddr *ifp;
1492 	unsigned int hash = inet6_addr_hash(addr);
1493 
1494 	rcu_read_lock_bh();
1495 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
1496 		if (!net_eq(dev_net(ifp->idev->dev), net))
1497 			continue;
1498 		if (ipv6_addr_equal(&ifp->addr, addr) &&
1499 		    !(ifp->flags&IFA_F_TENTATIVE) &&
1500 		    (dev == NULL || ifp->idev->dev == dev ||
1501 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1502 			rcu_read_unlock_bh();
1503 			return 1;
1504 		}
1505 	}
1506 
1507 	rcu_read_unlock_bh();
1508 	return 0;
1509 }
1510 EXPORT_SYMBOL(ipv6_chk_addr);
1511 
1512 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
1513 			       struct net_device *dev)
1514 {
1515 	unsigned int hash = inet6_addr_hash(addr);
1516 	struct inet6_ifaddr *ifp;
1517 
1518 	hlist_for_each_entry(ifp, &inet6_addr_lst[hash], addr_lst) {
1519 		if (!net_eq(dev_net(ifp->idev->dev), net))
1520 			continue;
1521 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1522 			if (dev == NULL || ifp->idev->dev == dev)
1523 				return true;
1524 		}
1525 	}
1526 	return false;
1527 }
1528 
1529 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
1530 {
1531 	struct inet6_dev *idev;
1532 	struct inet6_ifaddr *ifa;
1533 	int	onlink;
1534 
1535 	onlink = 0;
1536 	rcu_read_lock();
1537 	idev = __in6_dev_get(dev);
1538 	if (idev) {
1539 		read_lock_bh(&idev->lock);
1540 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
1541 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
1542 						   ifa->prefix_len);
1543 			if (onlink)
1544 				break;
1545 		}
1546 		read_unlock_bh(&idev->lock);
1547 	}
1548 	rcu_read_unlock();
1549 	return onlink;
1550 }
1551 EXPORT_SYMBOL(ipv6_chk_prefix);
1552 
1553 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
1554 				     struct net_device *dev, int strict)
1555 {
1556 	struct inet6_ifaddr *ifp, *result = NULL;
1557 	unsigned int hash = inet6_addr_hash(addr);
1558 
1559 	rcu_read_lock_bh();
1560 	hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[hash], addr_lst) {
1561 		if (!net_eq(dev_net(ifp->idev->dev), net))
1562 			continue;
1563 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1564 			if (dev == NULL || ifp->idev->dev == dev ||
1565 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
1566 				result = ifp;
1567 				in6_ifa_hold(ifp);
1568 				break;
1569 			}
1570 		}
1571 	}
1572 	rcu_read_unlock_bh();
1573 
1574 	return result;
1575 }
1576 
1577 /* Gets referenced address, destroys ifaddr */
1578 
1579 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
1580 {
1581 	if (ifp->flags&IFA_F_PERMANENT) {
1582 		spin_lock_bh(&ifp->lock);
1583 		addrconf_del_timer(ifp);
1584 		ifp->flags |= IFA_F_TENTATIVE;
1585 		if (dad_failed)
1586 			ifp->flags |= IFA_F_DADFAILED;
1587 		spin_unlock_bh(&ifp->lock);
1588 		if (dad_failed)
1589 			ipv6_ifa_notify(0, ifp);
1590 		in6_ifa_put(ifp);
1591 #ifdef CONFIG_IPV6_PRIVACY
1592 	} else if (ifp->flags&IFA_F_TEMPORARY) {
1593 		struct inet6_ifaddr *ifpub;
1594 		spin_lock_bh(&ifp->lock);
1595 		ifpub = ifp->ifpub;
1596 		if (ifpub) {
1597 			in6_ifa_hold(ifpub);
1598 			spin_unlock_bh(&ifp->lock);
1599 			ipv6_create_tempaddr(ifpub, ifp);
1600 			in6_ifa_put(ifpub);
1601 		} else {
1602 			spin_unlock_bh(&ifp->lock);
1603 		}
1604 		ipv6_del_addr(ifp);
1605 #endif
1606 	} else
1607 		ipv6_del_addr(ifp);
1608 }
1609 
1610 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
1611 {
1612 	int err = -ENOENT;
1613 
1614 	spin_lock(&ifp->state_lock);
1615 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
1616 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
1617 		err = 0;
1618 	}
1619 	spin_unlock(&ifp->state_lock);
1620 
1621 	return err;
1622 }
1623 
1624 void addrconf_dad_failure(struct inet6_ifaddr *ifp)
1625 {
1626 	struct inet6_dev *idev = ifp->idev;
1627 
1628 	if (addrconf_dad_end(ifp)) {
1629 		in6_ifa_put(ifp);
1630 		return;
1631 	}
1632 
1633 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c detected!\n",
1634 			     ifp->idev->dev->name, &ifp->addr);
1635 
1636 	if (idev->cnf.accept_dad > 1 && !idev->cnf.disable_ipv6) {
1637 		struct in6_addr addr;
1638 
1639 		addr.s6_addr32[0] = htonl(0xfe800000);
1640 		addr.s6_addr32[1] = 0;
1641 
1642 		if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
1643 		    ipv6_addr_equal(&ifp->addr, &addr)) {
1644 			/* DAD failed for link-local based on MAC address */
1645 			idev->cnf.disable_ipv6 = 1;
1646 
1647 			pr_info("%s: IPv6 being disabled!\n",
1648 				ifp->idev->dev->name);
1649 		}
1650 	}
1651 
1652 	addrconf_dad_stop(ifp, 1);
1653 }
1654 
1655 /* Join to solicited addr multicast group. */
1656 
1657 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
1658 {
1659 	struct in6_addr maddr;
1660 
1661 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
1662 		return;
1663 
1664 	addrconf_addr_solict_mult(addr, &maddr);
1665 	ipv6_dev_mc_inc(dev, &maddr);
1666 }
1667 
1668 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
1669 {
1670 	struct in6_addr maddr;
1671 
1672 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
1673 		return;
1674 
1675 	addrconf_addr_solict_mult(addr, &maddr);
1676 	__ipv6_dev_mc_dec(idev, &maddr);
1677 }
1678 
1679 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
1680 {
1681 	struct in6_addr addr;
1682 	if (ifp->prefix_len == 127) /* RFC 6164 */
1683 		return;
1684 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
1685 	if (ipv6_addr_any(&addr))
1686 		return;
1687 	ipv6_dev_ac_inc(ifp->idev->dev, &addr);
1688 }
1689 
1690 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
1691 {
1692 	struct in6_addr addr;
1693 	if (ifp->prefix_len == 127) /* RFC 6164 */
1694 		return;
1695 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
1696 	if (ipv6_addr_any(&addr))
1697 		return;
1698 	__ipv6_dev_ac_dec(ifp->idev, &addr);
1699 }
1700 
1701 static int addrconf_ifid_eui48(u8 *eui, struct net_device *dev)
1702 {
1703 	if (dev->addr_len != ETH_ALEN)
1704 		return -1;
1705 	memcpy(eui, dev->dev_addr, 3);
1706 	memcpy(eui + 5, dev->dev_addr + 3, 3);
1707 
1708 	/*
1709 	 * The zSeries OSA network cards can be shared among various
1710 	 * OS instances, but the OSA cards have only one MAC address.
1711 	 * This leads to duplicate address conflicts in conjunction
1712 	 * with IPv6 if more than one instance uses the same card.
1713 	 *
1714 	 * The driver for these cards can deliver a unique 16-bit
1715 	 * identifier for each instance sharing the same card.  It is
1716 	 * placed instead of 0xFFFE in the interface identifier.  The
1717 	 * "u" bit of the interface identifier is not inverted in this
1718 	 * case.  Hence the resulting interface identifier has local
1719 	 * scope according to RFC2373.
1720 	 */
1721 	if (dev->dev_id) {
1722 		eui[3] = (dev->dev_id >> 8) & 0xFF;
1723 		eui[4] = dev->dev_id & 0xFF;
1724 	} else {
1725 		eui[3] = 0xFF;
1726 		eui[4] = 0xFE;
1727 		eui[0] ^= 2;
1728 	}
1729 	return 0;
1730 }
1731 
1732 static int addrconf_ifid_eui64(u8 *eui, struct net_device *dev)
1733 {
1734 	if (dev->addr_len != IEEE802154_ADDR_LEN)
1735 		return -1;
1736 	memcpy(eui, dev->dev_addr, 8);
1737 	eui[0] ^= 2;
1738 	return 0;
1739 }
1740 
1741 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
1742 {
1743 	union fwnet_hwaddr *ha;
1744 
1745 	if (dev->addr_len != FWNET_ALEN)
1746 		return -1;
1747 
1748 	ha = (union fwnet_hwaddr *)dev->dev_addr;
1749 
1750 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
1751 	eui[0] ^= 2;
1752 	return 0;
1753 }
1754 
1755 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
1756 {
1757 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
1758 	if (dev->addr_len != ARCNET_ALEN)
1759 		return -1;
1760 	memset(eui, 0, 7);
1761 	eui[7] = *(u8 *)dev->dev_addr;
1762 	return 0;
1763 }
1764 
1765 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
1766 {
1767 	if (dev->addr_len != INFINIBAND_ALEN)
1768 		return -1;
1769 	memcpy(eui, dev->dev_addr + 12, 8);
1770 	eui[0] |= 2;
1771 	return 0;
1772 }
1773 
1774 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
1775 {
1776 	if (addr == 0)
1777 		return -1;
1778 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
1779 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
1780 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
1781 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
1782 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
1783 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
1784 	eui[1] = 0;
1785 	eui[2] = 0x5E;
1786 	eui[3] = 0xFE;
1787 	memcpy(eui + 4, &addr, 4);
1788 	return 0;
1789 }
1790 
1791 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
1792 {
1793 	if (dev->priv_flags & IFF_ISATAP)
1794 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
1795 	return -1;
1796 }
1797 
1798 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
1799 {
1800 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
1801 }
1802 
1803 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
1804 {
1805 	switch (dev->type) {
1806 	case ARPHRD_ETHER:
1807 	case ARPHRD_FDDI:
1808 		return addrconf_ifid_eui48(eui, dev);
1809 	case ARPHRD_ARCNET:
1810 		return addrconf_ifid_arcnet(eui, dev);
1811 	case ARPHRD_INFINIBAND:
1812 		return addrconf_ifid_infiniband(eui, dev);
1813 	case ARPHRD_SIT:
1814 		return addrconf_ifid_sit(eui, dev);
1815 	case ARPHRD_IPGRE:
1816 		return addrconf_ifid_gre(eui, dev);
1817 	case ARPHRD_IEEE802154:
1818 		return addrconf_ifid_eui64(eui, dev);
1819 	case ARPHRD_IEEE1394:
1820 		return addrconf_ifid_ieee1394(eui, dev);
1821 	}
1822 	return -1;
1823 }
1824 
1825 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
1826 {
1827 	int err = -1;
1828 	struct inet6_ifaddr *ifp;
1829 
1830 	read_lock_bh(&idev->lock);
1831 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
1832 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
1833 			memcpy(eui, ifp->addr.s6_addr+8, 8);
1834 			err = 0;
1835 			break;
1836 		}
1837 	}
1838 	read_unlock_bh(&idev->lock);
1839 	return err;
1840 }
1841 
1842 #ifdef CONFIG_IPV6_PRIVACY
1843 /* (re)generation of randomized interface identifier (RFC 3041 3.2, 3.5) */
1844 static void __ipv6_regen_rndid(struct inet6_dev *idev)
1845 {
1846 regen:
1847 	get_random_bytes(idev->rndid, sizeof(idev->rndid));
1848 	idev->rndid[0] &= ~0x02;
1849 
1850 	/*
1851 	 * <draft-ietf-ipngwg-temp-addresses-v2-00.txt>:
1852 	 * check if generated address is not inappropriate
1853 	 *
1854 	 *  - Reserved subnet anycast (RFC 2526)
1855 	 *	11111101 11....11 1xxxxxxx
1856 	 *  - ISATAP (RFC4214) 6.1
1857 	 *	00-00-5E-FE-xx-xx-xx-xx
1858 	 *  - value 0
1859 	 *  - XXX: already assigned to an address on the device
1860 	 */
1861 	if (idev->rndid[0] == 0xfd &&
1862 	    (idev->rndid[1]&idev->rndid[2]&idev->rndid[3]&idev->rndid[4]&idev->rndid[5]&idev->rndid[6]) == 0xff &&
1863 	    (idev->rndid[7]&0x80))
1864 		goto regen;
1865 	if ((idev->rndid[0]|idev->rndid[1]) == 0) {
1866 		if (idev->rndid[2] == 0x5e && idev->rndid[3] == 0xfe)
1867 			goto regen;
1868 		if ((idev->rndid[2]|idev->rndid[3]|idev->rndid[4]|idev->rndid[5]|idev->rndid[6]|idev->rndid[7]) == 0x00)
1869 			goto regen;
1870 	}
1871 }
1872 
1873 static void ipv6_regen_rndid(unsigned long data)
1874 {
1875 	struct inet6_dev *idev = (struct inet6_dev *) data;
1876 	unsigned long expires;
1877 
1878 	rcu_read_lock_bh();
1879 	write_lock_bh(&idev->lock);
1880 
1881 	if (idev->dead)
1882 		goto out;
1883 
1884 	__ipv6_regen_rndid(idev);
1885 
1886 	expires = jiffies +
1887 		idev->cnf.temp_prefered_lft * HZ -
1888 		idev->cnf.regen_max_retry * idev->cnf.dad_transmits * idev->nd_parms->retrans_time -
1889 		idev->cnf.max_desync_factor * HZ;
1890 	if (time_before(expires, jiffies)) {
1891 		pr_warn("%s: too short regeneration interval; timer disabled for %s\n",
1892 			__func__, idev->dev->name);
1893 		goto out;
1894 	}
1895 
1896 	if (!mod_timer(&idev->regen_timer, expires))
1897 		in6_dev_hold(idev);
1898 
1899 out:
1900 	write_unlock_bh(&idev->lock);
1901 	rcu_read_unlock_bh();
1902 	in6_dev_put(idev);
1903 }
1904 
1905 static void  __ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr)
1906 {
1907 	if (tmpaddr && memcmp(idev->rndid, &tmpaddr->s6_addr[8], 8) == 0)
1908 		__ipv6_regen_rndid(idev);
1909 }
1910 #endif
1911 
1912 /*
1913  *	Add prefix route.
1914  */
1915 
1916 static void
1917 addrconf_prefix_route(struct in6_addr *pfx, int plen, struct net_device *dev,
1918 		      unsigned long expires, u32 flags)
1919 {
1920 	struct fib6_config cfg = {
1921 		.fc_table = RT6_TABLE_PREFIX,
1922 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
1923 		.fc_ifindex = dev->ifindex,
1924 		.fc_expires = expires,
1925 		.fc_dst_len = plen,
1926 		.fc_flags = RTF_UP | flags,
1927 		.fc_nlinfo.nl_net = dev_net(dev),
1928 		.fc_protocol = RTPROT_KERNEL,
1929 	};
1930 
1931 	cfg.fc_dst = *pfx;
1932 
1933 	/* Prevent useless cloning on PtP SIT.
1934 	   This thing is done here expecting that the whole
1935 	   class of non-broadcast devices need not cloning.
1936 	 */
1937 #if IS_ENABLED(CONFIG_IPV6_SIT)
1938 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
1939 		cfg.fc_flags |= RTF_NONEXTHOP;
1940 #endif
1941 
1942 	ip6_route_add(&cfg);
1943 }
1944 
1945 
1946 static struct rt6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
1947 						  int plen,
1948 						  const struct net_device *dev,
1949 						  u32 flags, u32 noflags)
1950 {
1951 	struct fib6_node *fn;
1952 	struct rt6_info *rt = NULL;
1953 	struct fib6_table *table;
1954 
1955 	table = fib6_get_table(dev_net(dev), RT6_TABLE_PREFIX);
1956 	if (table == NULL)
1957 		return NULL;
1958 
1959 	read_lock_bh(&table->tb6_lock);
1960 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0);
1961 	if (!fn)
1962 		goto out;
1963 	for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
1964 		if (rt->dst.dev->ifindex != dev->ifindex)
1965 			continue;
1966 		if ((rt->rt6i_flags & flags) != flags)
1967 			continue;
1968 		if ((rt->rt6i_flags & noflags) != 0)
1969 			continue;
1970 		dst_hold(&rt->dst);
1971 		break;
1972 	}
1973 out:
1974 	read_unlock_bh(&table->tb6_lock);
1975 	return rt;
1976 }
1977 
1978 
1979 /* Create "default" multicast route to the interface */
1980 
1981 static void addrconf_add_mroute(struct net_device *dev)
1982 {
1983 	struct fib6_config cfg = {
1984 		.fc_table = RT6_TABLE_LOCAL,
1985 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
1986 		.fc_ifindex = dev->ifindex,
1987 		.fc_dst_len = 8,
1988 		.fc_flags = RTF_UP,
1989 		.fc_nlinfo.nl_net = dev_net(dev),
1990 	};
1991 
1992 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
1993 
1994 	ip6_route_add(&cfg);
1995 }
1996 
1997 #if IS_ENABLED(CONFIG_IPV6_SIT)
1998 static void sit_route_add(struct net_device *dev)
1999 {
2000 	struct fib6_config cfg = {
2001 		.fc_table = RT6_TABLE_MAIN,
2002 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2003 		.fc_ifindex = dev->ifindex,
2004 		.fc_dst_len = 96,
2005 		.fc_flags = RTF_UP | RTF_NONEXTHOP,
2006 		.fc_nlinfo.nl_net = dev_net(dev),
2007 	};
2008 
2009 	/* prefix length - 96 bits "::d.d.d.d" */
2010 	ip6_route_add(&cfg);
2011 }
2012 #endif
2013 
2014 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2015 {
2016 	struct inet6_dev *idev;
2017 
2018 	ASSERT_RTNL();
2019 
2020 	idev = ipv6_find_idev(dev);
2021 	if (!idev)
2022 		return ERR_PTR(-ENOBUFS);
2023 
2024 	if (idev->cnf.disable_ipv6)
2025 		return ERR_PTR(-EACCES);
2026 
2027 	/* Add default multicast route */
2028 	if (!(dev->flags & IFF_LOOPBACK))
2029 		addrconf_add_mroute(dev);
2030 
2031 	return idev;
2032 }
2033 
2034 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2035 {
2036 	struct prefix_info *pinfo;
2037 	__u32 valid_lft;
2038 	__u32 prefered_lft;
2039 	int addr_type;
2040 	struct inet6_dev *in6_dev;
2041 	struct net *net = dev_net(dev);
2042 
2043 	pinfo = (struct prefix_info *) opt;
2044 
2045 	if (len < sizeof(struct prefix_info)) {
2046 		ADBG(("addrconf: prefix option too short\n"));
2047 		return;
2048 	}
2049 
2050 	/*
2051 	 *	Validation checks ([ADDRCONF], page 19)
2052 	 */
2053 
2054 	addr_type = ipv6_addr_type(&pinfo->prefix);
2055 
2056 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2057 		return;
2058 
2059 	valid_lft = ntohl(pinfo->valid);
2060 	prefered_lft = ntohl(pinfo->prefered);
2061 
2062 	if (prefered_lft > valid_lft) {
2063 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2064 		return;
2065 	}
2066 
2067 	in6_dev = in6_dev_get(dev);
2068 
2069 	if (in6_dev == NULL) {
2070 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2071 				    dev->name);
2072 		return;
2073 	}
2074 
2075 	/*
2076 	 *	Two things going on here:
2077 	 *	1) Add routes for on-link prefixes
2078 	 *	2) Configure prefixes with the auto flag set
2079 	 */
2080 
2081 	if (pinfo->onlink) {
2082 		struct rt6_info *rt;
2083 		unsigned long rt_expires;
2084 
2085 		/* Avoid arithmetic overflow. Really, we could
2086 		 * save rt_expires in seconds, likely valid_lft,
2087 		 * but it would require division in fib gc, that it
2088 		 * not good.
2089 		 */
2090 		if (HZ > USER_HZ)
2091 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2092 		else
2093 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2094 
2095 		if (addrconf_finite_timeout(rt_expires))
2096 			rt_expires *= HZ;
2097 
2098 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2099 					       pinfo->prefix_len,
2100 					       dev,
2101 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2102 					       RTF_GATEWAY | RTF_DEFAULT);
2103 
2104 		if (rt) {
2105 			/* Autoconf prefix route */
2106 			if (valid_lft == 0) {
2107 				ip6_del_rt(rt);
2108 				rt = NULL;
2109 			} else if (addrconf_finite_timeout(rt_expires)) {
2110 				/* not infinity */
2111 				rt6_set_expires(rt, jiffies + rt_expires);
2112 			} else {
2113 				rt6_clean_expires(rt);
2114 			}
2115 		} else if (valid_lft) {
2116 			clock_t expires = 0;
2117 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2118 			if (addrconf_finite_timeout(rt_expires)) {
2119 				/* not infinity */
2120 				flags |= RTF_EXPIRES;
2121 				expires = jiffies_to_clock_t(rt_expires);
2122 			}
2123 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2124 					      dev, expires, flags);
2125 		}
2126 		ip6_rt_put(rt);
2127 	}
2128 
2129 	/* Try to figure out our local address for this prefix */
2130 
2131 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
2132 		struct inet6_ifaddr *ifp;
2133 		struct in6_addr addr;
2134 		int create = 0, update_lft = 0;
2135 		bool tokenized = false;
2136 
2137 		if (pinfo->prefix_len == 64) {
2138 			memcpy(&addr, &pinfo->prefix, 8);
2139 
2140 			if (!ipv6_addr_any(&in6_dev->token)) {
2141 				read_lock_bh(&in6_dev->lock);
2142 				memcpy(addr.s6_addr + 8,
2143 				       in6_dev->token.s6_addr + 8, 8);
2144 				read_unlock_bh(&in6_dev->lock);
2145 				tokenized = true;
2146 			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2147 				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2148 				in6_dev_put(in6_dev);
2149 				return;
2150 			}
2151 			goto ok;
2152 		}
2153 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2154 				    pinfo->prefix_len);
2155 		in6_dev_put(in6_dev);
2156 		return;
2157 
2158 ok:
2159 
2160 		ifp = ipv6_get_ifaddr(net, &addr, dev, 1);
2161 
2162 		if (ifp == NULL && valid_lft) {
2163 			int max_addresses = in6_dev->cnf.max_addresses;
2164 			u32 addr_flags = 0;
2165 
2166 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2167 			if (in6_dev->cnf.optimistic_dad &&
2168 			    !net->ipv6.devconf_all->forwarding && sllao)
2169 				addr_flags = IFA_F_OPTIMISTIC;
2170 #endif
2171 
2172 			/* Do not allow to create too much of autoconfigured
2173 			 * addresses; this would be too easy way to crash kernel.
2174 			 */
2175 			if (!max_addresses ||
2176 			    ipv6_count_addresses(in6_dev) < max_addresses)
2177 				ifp = ipv6_add_addr(in6_dev, &addr, pinfo->prefix_len,
2178 						    addr_type&IPV6_ADDR_SCOPE_MASK,
2179 						    addr_flags);
2180 
2181 			if (IS_ERR_OR_NULL(ifp)) {
2182 				in6_dev_put(in6_dev);
2183 				return;
2184 			}
2185 
2186 			update_lft = create = 1;
2187 			ifp->cstamp = jiffies;
2188 			ifp->tokenized = tokenized;
2189 			addrconf_dad_start(ifp);
2190 		}
2191 
2192 		if (ifp) {
2193 			int flags;
2194 			unsigned long now;
2195 #ifdef CONFIG_IPV6_PRIVACY
2196 			struct inet6_ifaddr *ift;
2197 #endif
2198 			u32 stored_lft;
2199 
2200 			/* update lifetime (RFC2462 5.5.3 e) */
2201 			spin_lock(&ifp->lock);
2202 			now = jiffies;
2203 			if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2204 				stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2205 			else
2206 				stored_lft = 0;
2207 			if (!update_lft && stored_lft) {
2208 				if (valid_lft > MIN_VALID_LIFETIME ||
2209 				    valid_lft > stored_lft)
2210 					update_lft = 1;
2211 				else if (stored_lft <= MIN_VALID_LIFETIME) {
2212 					/* valid_lft <= stored_lft is always true */
2213 					/*
2214 					 * RFC 4862 Section 5.5.3e:
2215 					 * "Note that the preferred lifetime of
2216 					 *  the corresponding address is always
2217 					 *  reset to the Preferred Lifetime in
2218 					 *  the received Prefix Information
2219 					 *  option, regardless of whether the
2220 					 *  valid lifetime is also reset or
2221 					 *  ignored."
2222 					 *
2223 					 *  So if the preferred lifetime in
2224 					 *  this advertisement is different
2225 					 *  than what we have stored, but the
2226 					 *  valid lifetime is invalid, just
2227 					 *  reset prefered_lft.
2228 					 *
2229 					 *  We must set the valid lifetime
2230 					 *  to the stored lifetime since we'll
2231 					 *  be updating the timestamp below,
2232 					 *  else we'll set it back to the
2233 					 *  minimum.
2234 					 */
2235 					if (prefered_lft != ifp->prefered_lft) {
2236 						valid_lft = stored_lft;
2237 						update_lft = 1;
2238 					}
2239 				} else {
2240 					valid_lft = MIN_VALID_LIFETIME;
2241 					if (valid_lft < prefered_lft)
2242 						prefered_lft = valid_lft;
2243 					update_lft = 1;
2244 				}
2245 			}
2246 
2247 			if (update_lft) {
2248 				ifp->valid_lft = valid_lft;
2249 				ifp->prefered_lft = prefered_lft;
2250 				ifp->tstamp = now;
2251 				flags = ifp->flags;
2252 				ifp->flags &= ~IFA_F_DEPRECATED;
2253 				spin_unlock(&ifp->lock);
2254 
2255 				if (!(flags&IFA_F_TENTATIVE))
2256 					ipv6_ifa_notify(0, ifp);
2257 			} else
2258 				spin_unlock(&ifp->lock);
2259 
2260 #ifdef CONFIG_IPV6_PRIVACY
2261 			read_lock_bh(&in6_dev->lock);
2262 			/* update all temporary addresses in the list */
2263 			list_for_each_entry(ift, &in6_dev->tempaddr_list,
2264 					    tmp_list) {
2265 				int age, max_valid, max_prefered;
2266 
2267 				if (ifp != ift->ifpub)
2268 					continue;
2269 
2270 				/*
2271 				 * RFC 4941 section 3.3:
2272 				 * If a received option will extend the lifetime
2273 				 * of a public address, the lifetimes of
2274 				 * temporary addresses should be extended,
2275 				 * subject to the overall constraint that no
2276 				 * temporary addresses should ever remain
2277 				 * "valid" or "preferred" for a time longer than
2278 				 * (TEMP_VALID_LIFETIME) or
2279 				 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR),
2280 				 * respectively.
2281 				 */
2282 				age = (now - ift->cstamp) / HZ;
2283 				max_valid = in6_dev->cnf.temp_valid_lft - age;
2284 				if (max_valid < 0)
2285 					max_valid = 0;
2286 
2287 				max_prefered = in6_dev->cnf.temp_prefered_lft -
2288 					       in6_dev->cnf.max_desync_factor -
2289 					       age;
2290 				if (max_prefered < 0)
2291 					max_prefered = 0;
2292 
2293 				if (valid_lft > max_valid)
2294 					valid_lft = max_valid;
2295 
2296 				if (prefered_lft > max_prefered)
2297 					prefered_lft = max_prefered;
2298 
2299 				spin_lock(&ift->lock);
2300 				flags = ift->flags;
2301 				ift->valid_lft = valid_lft;
2302 				ift->prefered_lft = prefered_lft;
2303 				ift->tstamp = now;
2304 				if (prefered_lft > 0)
2305 					ift->flags &= ~IFA_F_DEPRECATED;
2306 
2307 				spin_unlock(&ift->lock);
2308 				if (!(flags&IFA_F_TENTATIVE))
2309 					ipv6_ifa_notify(0, ift);
2310 			}
2311 
2312 			if ((create || list_empty(&in6_dev->tempaddr_list)) && in6_dev->cnf.use_tempaddr > 0) {
2313 				/*
2314 				 * When a new public address is created as
2315 				 * described in [ADDRCONF], also create a new
2316 				 * temporary address. Also create a temporary
2317 				 * address if it's enabled but no temporary
2318 				 * address currently exists.
2319 				 */
2320 				read_unlock_bh(&in6_dev->lock);
2321 				ipv6_create_tempaddr(ifp, NULL);
2322 			} else {
2323 				read_unlock_bh(&in6_dev->lock);
2324 			}
2325 #endif
2326 			in6_ifa_put(ifp);
2327 			addrconf_verify(0);
2328 		}
2329 	}
2330 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2331 	in6_dev_put(in6_dev);
2332 }
2333 
2334 /*
2335  *	Set destination address.
2336  *	Special case for SIT interfaces where we create a new "virtual"
2337  *	device.
2338  */
2339 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2340 {
2341 	struct in6_ifreq ireq;
2342 	struct net_device *dev;
2343 	int err = -EINVAL;
2344 
2345 	rtnl_lock();
2346 
2347 	err = -EFAULT;
2348 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2349 		goto err_exit;
2350 
2351 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2352 
2353 	err = -ENODEV;
2354 	if (dev == NULL)
2355 		goto err_exit;
2356 
2357 #if IS_ENABLED(CONFIG_IPV6_SIT)
2358 	if (dev->type == ARPHRD_SIT) {
2359 		const struct net_device_ops *ops = dev->netdev_ops;
2360 		struct ifreq ifr;
2361 		struct ip_tunnel_parm p;
2362 
2363 		err = -EADDRNOTAVAIL;
2364 		if (!(ipv6_addr_type(&ireq.ifr6_addr) & IPV6_ADDR_COMPATv4))
2365 			goto err_exit;
2366 
2367 		memset(&p, 0, sizeof(p));
2368 		p.iph.daddr = ireq.ifr6_addr.s6_addr32[3];
2369 		p.iph.saddr = 0;
2370 		p.iph.version = 4;
2371 		p.iph.ihl = 5;
2372 		p.iph.protocol = IPPROTO_IPV6;
2373 		p.iph.ttl = 64;
2374 		ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
2375 
2376 		if (ops->ndo_do_ioctl) {
2377 			mm_segment_t oldfs = get_fs();
2378 
2379 			set_fs(KERNEL_DS);
2380 			err = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
2381 			set_fs(oldfs);
2382 		} else
2383 			err = -EOPNOTSUPP;
2384 
2385 		if (err == 0) {
2386 			err = -ENOBUFS;
2387 			dev = __dev_get_by_name(net, p.name);
2388 			if (!dev)
2389 				goto err_exit;
2390 			err = dev_open(dev);
2391 		}
2392 	}
2393 #endif
2394 
2395 err_exit:
2396 	rtnl_unlock();
2397 	return err;
2398 }
2399 
2400 /*
2401  *	Manual configuration of address on an interface
2402  */
2403 static int inet6_addr_add(struct net *net, int ifindex, const struct in6_addr *pfx,
2404 			  const struct in6_addr *peer_pfx,
2405 			  unsigned int plen, __u8 ifa_flags, __u32 prefered_lft,
2406 			  __u32 valid_lft)
2407 {
2408 	struct inet6_ifaddr *ifp;
2409 	struct inet6_dev *idev;
2410 	struct net_device *dev;
2411 	int scope;
2412 	u32 flags;
2413 	clock_t expires;
2414 	unsigned long timeout;
2415 
2416 	ASSERT_RTNL();
2417 
2418 	if (plen > 128)
2419 		return -EINVAL;
2420 
2421 	/* check the lifetime */
2422 	if (!valid_lft || prefered_lft > valid_lft)
2423 		return -EINVAL;
2424 
2425 	dev = __dev_get_by_index(net, ifindex);
2426 	if (!dev)
2427 		return -ENODEV;
2428 
2429 	idev = addrconf_add_dev(dev);
2430 	if (IS_ERR(idev))
2431 		return PTR_ERR(idev);
2432 
2433 	scope = ipv6_addr_scope(pfx);
2434 
2435 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
2436 	if (addrconf_finite_timeout(timeout)) {
2437 		expires = jiffies_to_clock_t(timeout * HZ);
2438 		valid_lft = timeout;
2439 		flags = RTF_EXPIRES;
2440 	} else {
2441 		expires = 0;
2442 		flags = 0;
2443 		ifa_flags |= IFA_F_PERMANENT;
2444 	}
2445 
2446 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
2447 	if (addrconf_finite_timeout(timeout)) {
2448 		if (timeout == 0)
2449 			ifa_flags |= IFA_F_DEPRECATED;
2450 		prefered_lft = timeout;
2451 	}
2452 
2453 	ifp = ipv6_add_addr(idev, pfx, plen, scope, ifa_flags);
2454 
2455 	if (!IS_ERR(ifp)) {
2456 		spin_lock_bh(&ifp->lock);
2457 		ifp->valid_lft = valid_lft;
2458 		ifp->prefered_lft = prefered_lft;
2459 		ifp->tstamp = jiffies;
2460 		if (peer_pfx)
2461 			ifp->peer_addr = *peer_pfx;
2462 		spin_unlock_bh(&ifp->lock);
2463 
2464 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, dev,
2465 				      expires, flags);
2466 		/*
2467 		 * Note that section 3.1 of RFC 4429 indicates
2468 		 * that the Optimistic flag should not be set for
2469 		 * manually configured addresses
2470 		 */
2471 		addrconf_dad_start(ifp);
2472 		in6_ifa_put(ifp);
2473 		addrconf_verify(0);
2474 		return 0;
2475 	}
2476 
2477 	return PTR_ERR(ifp);
2478 }
2479 
2480 static int inet6_addr_del(struct net *net, int ifindex, const struct in6_addr *pfx,
2481 			  unsigned int plen)
2482 {
2483 	struct inet6_ifaddr *ifp;
2484 	struct inet6_dev *idev;
2485 	struct net_device *dev;
2486 
2487 	if (plen > 128)
2488 		return -EINVAL;
2489 
2490 	dev = __dev_get_by_index(net, ifindex);
2491 	if (!dev)
2492 		return -ENODEV;
2493 
2494 	if ((idev = __in6_dev_get(dev)) == NULL)
2495 		return -ENXIO;
2496 
2497 	read_lock_bh(&idev->lock);
2498 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
2499 		if (ifp->prefix_len == plen &&
2500 		    ipv6_addr_equal(pfx, &ifp->addr)) {
2501 			in6_ifa_hold(ifp);
2502 			read_unlock_bh(&idev->lock);
2503 
2504 			ipv6_del_addr(ifp);
2505 
2506 			/* If the last address is deleted administratively,
2507 			   disable IPv6 on this interface.
2508 			 */
2509 			if (list_empty(&idev->addr_list))
2510 				addrconf_ifdown(idev->dev, 1);
2511 			return 0;
2512 		}
2513 	}
2514 	read_unlock_bh(&idev->lock);
2515 	return -EADDRNOTAVAIL;
2516 }
2517 
2518 
2519 int addrconf_add_ifaddr(struct net *net, void __user *arg)
2520 {
2521 	struct in6_ifreq ireq;
2522 	int err;
2523 
2524 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2525 		return -EPERM;
2526 
2527 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2528 		return -EFAULT;
2529 
2530 	rtnl_lock();
2531 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &ireq.ifr6_addr, NULL,
2532 			     ireq.ifr6_prefixlen, IFA_F_PERMANENT,
2533 			     INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
2534 	rtnl_unlock();
2535 	return err;
2536 }
2537 
2538 int addrconf_del_ifaddr(struct net *net, void __user *arg)
2539 {
2540 	struct in6_ifreq ireq;
2541 	int err;
2542 
2543 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2544 		return -EPERM;
2545 
2546 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2547 		return -EFAULT;
2548 
2549 	rtnl_lock();
2550 	err = inet6_addr_del(net, ireq.ifr6_ifindex, &ireq.ifr6_addr,
2551 			     ireq.ifr6_prefixlen);
2552 	rtnl_unlock();
2553 	return err;
2554 }
2555 
2556 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
2557 		     int plen, int scope)
2558 {
2559 	struct inet6_ifaddr *ifp;
2560 
2561 	ifp = ipv6_add_addr(idev, addr, plen, scope, IFA_F_PERMANENT);
2562 	if (!IS_ERR(ifp)) {
2563 		spin_lock_bh(&ifp->lock);
2564 		ifp->flags &= ~IFA_F_TENTATIVE;
2565 		spin_unlock_bh(&ifp->lock);
2566 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
2567 		in6_ifa_put(ifp);
2568 	}
2569 }
2570 
2571 #if IS_ENABLED(CONFIG_IPV6_SIT)
2572 static void sit_add_v4_addrs(struct inet6_dev *idev)
2573 {
2574 	struct in6_addr addr;
2575 	struct net_device *dev;
2576 	struct net *net = dev_net(idev->dev);
2577 	int scope;
2578 
2579 	ASSERT_RTNL();
2580 
2581 	memset(&addr, 0, sizeof(struct in6_addr));
2582 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
2583 
2584 	if (idev->dev->flags&IFF_POINTOPOINT) {
2585 		addr.s6_addr32[0] = htonl(0xfe800000);
2586 		scope = IFA_LINK;
2587 	} else {
2588 		scope = IPV6_ADDR_COMPATv4;
2589 	}
2590 
2591 	if (addr.s6_addr32[3]) {
2592 		add_addr(idev, &addr, 128, scope);
2593 		return;
2594 	}
2595 
2596 	for_each_netdev(net, dev) {
2597 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
2598 		if (in_dev && (dev->flags & IFF_UP)) {
2599 			struct in_ifaddr *ifa;
2600 
2601 			int flag = scope;
2602 
2603 			for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
2604 				int plen;
2605 
2606 				addr.s6_addr32[3] = ifa->ifa_local;
2607 
2608 				if (ifa->ifa_scope == RT_SCOPE_LINK)
2609 					continue;
2610 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
2611 					if (idev->dev->flags&IFF_POINTOPOINT)
2612 						continue;
2613 					flag |= IFA_HOST;
2614 				}
2615 				if (idev->dev->flags&IFF_POINTOPOINT)
2616 					plen = 64;
2617 				else
2618 					plen = 96;
2619 
2620 				add_addr(idev, &addr, plen, flag);
2621 			}
2622 		}
2623 	}
2624 }
2625 #endif
2626 
2627 static void init_loopback(struct net_device *dev)
2628 {
2629 	struct inet6_dev  *idev;
2630 	struct net_device *sp_dev;
2631 	struct inet6_ifaddr *sp_ifa;
2632 	struct rt6_info *sp_rt;
2633 
2634 	/* ::1 */
2635 
2636 	ASSERT_RTNL();
2637 
2638 	if ((idev = ipv6_find_idev(dev)) == NULL) {
2639 		pr_debug("%s: add_dev failed\n", __func__);
2640 		return;
2641 	}
2642 
2643 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST);
2644 
2645 	/* Add routes to other interface's IPv6 addresses */
2646 	for_each_netdev(dev_net(dev), sp_dev) {
2647 		if (!strcmp(sp_dev->name, dev->name))
2648 			continue;
2649 
2650 		idev = __in6_dev_get(sp_dev);
2651 		if (!idev)
2652 			continue;
2653 
2654 		read_lock_bh(&idev->lock);
2655 		list_for_each_entry(sp_ifa, &idev->addr_list, if_list) {
2656 
2657 			if (sp_ifa->flags & (IFA_F_DADFAILED | IFA_F_TENTATIVE))
2658 				continue;
2659 
2660 			sp_rt = addrconf_dst_alloc(idev, &sp_ifa->addr, 0);
2661 
2662 			/* Failure cases are ignored */
2663 			if (!IS_ERR(sp_rt)) {
2664 				sp_ifa->rt = sp_rt;
2665 				ip6_ins_rt(sp_rt);
2666 			}
2667 		}
2668 		read_unlock_bh(&idev->lock);
2669 	}
2670 }
2671 
2672 static void addrconf_add_linklocal(struct inet6_dev *idev, const struct in6_addr *addr)
2673 {
2674 	struct inet6_ifaddr *ifp;
2675 	u32 addr_flags = IFA_F_PERMANENT;
2676 
2677 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2678 	if (idev->cnf.optimistic_dad &&
2679 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
2680 		addr_flags |= IFA_F_OPTIMISTIC;
2681 #endif
2682 
2683 
2684 	ifp = ipv6_add_addr(idev, addr, 64, IFA_LINK, addr_flags);
2685 	if (!IS_ERR(ifp)) {
2686 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, idev->dev, 0, 0);
2687 		addrconf_dad_start(ifp);
2688 		in6_ifa_put(ifp);
2689 	}
2690 }
2691 
2692 static void addrconf_dev_config(struct net_device *dev)
2693 {
2694 	struct in6_addr addr;
2695 	struct inet6_dev *idev;
2696 
2697 	ASSERT_RTNL();
2698 
2699 	if ((dev->type != ARPHRD_ETHER) &&
2700 	    (dev->type != ARPHRD_FDDI) &&
2701 	    (dev->type != ARPHRD_ARCNET) &&
2702 	    (dev->type != ARPHRD_INFINIBAND) &&
2703 	    (dev->type != ARPHRD_IEEE802154) &&
2704 	    (dev->type != ARPHRD_IEEE1394)) {
2705 		/* Alas, we support only Ethernet autoconfiguration. */
2706 		return;
2707 	}
2708 
2709 	idev = addrconf_add_dev(dev);
2710 	if (IS_ERR(idev))
2711 		return;
2712 
2713 	memset(&addr, 0, sizeof(struct in6_addr));
2714 	addr.s6_addr32[0] = htonl(0xFE800000);
2715 
2716 	if (ipv6_generate_eui64(addr.s6_addr + 8, dev) == 0)
2717 		addrconf_add_linklocal(idev, &addr);
2718 }
2719 
2720 #if IS_ENABLED(CONFIG_IPV6_SIT)
2721 static void addrconf_sit_config(struct net_device *dev)
2722 {
2723 	struct inet6_dev *idev;
2724 
2725 	ASSERT_RTNL();
2726 
2727 	/*
2728 	 * Configure the tunnel with one of our IPv4
2729 	 * addresses... we should configure all of
2730 	 * our v4 addrs in the tunnel
2731 	 */
2732 
2733 	if ((idev = ipv6_find_idev(dev)) == NULL) {
2734 		pr_debug("%s: add_dev failed\n", __func__);
2735 		return;
2736 	}
2737 
2738 	if (dev->priv_flags & IFF_ISATAP) {
2739 		struct in6_addr addr;
2740 
2741 		ipv6_addr_set(&addr,  htonl(0xFE800000), 0, 0, 0);
2742 		addrconf_prefix_route(&addr, 64, dev, 0, 0);
2743 		if (!ipv6_generate_eui64(addr.s6_addr + 8, dev))
2744 			addrconf_add_linklocal(idev, &addr);
2745 		return;
2746 	}
2747 
2748 	sit_add_v4_addrs(idev);
2749 
2750 	if (dev->flags&IFF_POINTOPOINT)
2751 		addrconf_add_mroute(dev);
2752 	else
2753 		sit_route_add(dev);
2754 }
2755 #endif
2756 
2757 #if IS_ENABLED(CONFIG_NET_IPGRE)
2758 static void addrconf_gre_config(struct net_device *dev)
2759 {
2760 	struct inet6_dev *idev;
2761 	struct in6_addr addr;
2762 
2763 	pr_info("%s(%s)\n", __func__, dev->name);
2764 
2765 	ASSERT_RTNL();
2766 
2767 	if ((idev = ipv6_find_idev(dev)) == NULL) {
2768 		pr_debug("%s: add_dev failed\n", __func__);
2769 		return;
2770 	}
2771 
2772 	ipv6_addr_set(&addr,  htonl(0xFE800000), 0, 0, 0);
2773 	addrconf_prefix_route(&addr, 64, dev, 0, 0);
2774 
2775 	if (!ipv6_generate_eui64(addr.s6_addr + 8, dev))
2776 		addrconf_add_linklocal(idev, &addr);
2777 }
2778 #endif
2779 
2780 static inline int
2781 ipv6_inherit_linklocal(struct inet6_dev *idev, struct net_device *link_dev)
2782 {
2783 	struct in6_addr lladdr;
2784 
2785 	if (!ipv6_get_lladdr(link_dev, &lladdr, IFA_F_TENTATIVE)) {
2786 		addrconf_add_linklocal(idev, &lladdr);
2787 		return 0;
2788 	}
2789 	return -1;
2790 }
2791 
2792 static void ip6_tnl_add_linklocal(struct inet6_dev *idev)
2793 {
2794 	struct net_device *link_dev;
2795 	struct net *net = dev_net(idev->dev);
2796 
2797 	/* first try to inherit the link-local address from the link device */
2798 	if (idev->dev->iflink &&
2799 	    (link_dev = __dev_get_by_index(net, idev->dev->iflink))) {
2800 		if (!ipv6_inherit_linklocal(idev, link_dev))
2801 			return;
2802 	}
2803 	/* then try to inherit it from any device */
2804 	for_each_netdev(net, link_dev) {
2805 		if (!ipv6_inherit_linklocal(idev, link_dev))
2806 			return;
2807 	}
2808 	pr_debug("init ip6-ip6: add_linklocal failed\n");
2809 }
2810 
2811 /*
2812  * Autoconfigure tunnel with a link-local address so routing protocols,
2813  * DHCPv6, MLD etc. can be run over the virtual link
2814  */
2815 
2816 static void addrconf_ip6_tnl_config(struct net_device *dev)
2817 {
2818 	struct inet6_dev *idev;
2819 
2820 	ASSERT_RTNL();
2821 
2822 	idev = addrconf_add_dev(dev);
2823 	if (IS_ERR(idev)) {
2824 		pr_debug("init ip6-ip6: add_dev failed\n");
2825 		return;
2826 	}
2827 	ip6_tnl_add_linklocal(idev);
2828 }
2829 
2830 static int addrconf_notify(struct notifier_block *this, unsigned long event,
2831 			   void *ptr)
2832 {
2833 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
2834 	struct inet6_dev *idev = __in6_dev_get(dev);
2835 	int run_pending = 0;
2836 	int err;
2837 
2838 	switch (event) {
2839 	case NETDEV_REGISTER:
2840 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
2841 			idev = ipv6_add_dev(dev);
2842 			if (!idev)
2843 				return notifier_from_errno(-ENOMEM);
2844 		}
2845 		break;
2846 
2847 	case NETDEV_UP:
2848 	case NETDEV_CHANGE:
2849 		if (dev->flags & IFF_SLAVE)
2850 			break;
2851 
2852 		if (event == NETDEV_UP) {
2853 			if (!addrconf_qdisc_ok(dev)) {
2854 				/* device is not ready yet. */
2855 				pr_info("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
2856 					dev->name);
2857 				break;
2858 			}
2859 
2860 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
2861 				idev = ipv6_add_dev(dev);
2862 
2863 			if (idev) {
2864 				idev->if_flags |= IF_READY;
2865 				run_pending = 1;
2866 			}
2867 		} else {
2868 			if (!addrconf_qdisc_ok(dev)) {
2869 				/* device is still not ready. */
2870 				break;
2871 			}
2872 
2873 			if (idev) {
2874 				if (idev->if_flags & IF_READY)
2875 					/* device is already configured. */
2876 					break;
2877 				idev->if_flags |= IF_READY;
2878 			}
2879 
2880 			pr_info("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
2881 				dev->name);
2882 
2883 			run_pending = 1;
2884 		}
2885 
2886 		switch (dev->type) {
2887 #if IS_ENABLED(CONFIG_IPV6_SIT)
2888 		case ARPHRD_SIT:
2889 			addrconf_sit_config(dev);
2890 			break;
2891 #endif
2892 #if IS_ENABLED(CONFIG_NET_IPGRE)
2893 		case ARPHRD_IPGRE:
2894 			addrconf_gre_config(dev);
2895 			break;
2896 #endif
2897 		case ARPHRD_TUNNEL6:
2898 			addrconf_ip6_tnl_config(dev);
2899 			break;
2900 		case ARPHRD_LOOPBACK:
2901 			init_loopback(dev);
2902 			break;
2903 
2904 		default:
2905 			addrconf_dev_config(dev);
2906 			break;
2907 		}
2908 
2909 		if (idev) {
2910 			if (run_pending)
2911 				addrconf_dad_run(idev);
2912 
2913 			/*
2914 			 * If the MTU changed during the interface down,
2915 			 * when the interface up, the changed MTU must be
2916 			 * reflected in the idev as well as routers.
2917 			 */
2918 			if (idev->cnf.mtu6 != dev->mtu &&
2919 			    dev->mtu >= IPV6_MIN_MTU) {
2920 				rt6_mtu_change(dev, dev->mtu);
2921 				idev->cnf.mtu6 = dev->mtu;
2922 			}
2923 			idev->tstamp = jiffies;
2924 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
2925 
2926 			/*
2927 			 * If the changed mtu during down is lower than
2928 			 * IPV6_MIN_MTU stop IPv6 on this interface.
2929 			 */
2930 			if (dev->mtu < IPV6_MIN_MTU)
2931 				addrconf_ifdown(dev, 1);
2932 		}
2933 		break;
2934 
2935 	case NETDEV_CHANGEMTU:
2936 		if (idev && dev->mtu >= IPV6_MIN_MTU) {
2937 			rt6_mtu_change(dev, dev->mtu);
2938 			idev->cnf.mtu6 = dev->mtu;
2939 			break;
2940 		}
2941 
2942 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
2943 			idev = ipv6_add_dev(dev);
2944 			if (idev)
2945 				break;
2946 		}
2947 
2948 		/*
2949 		 * MTU falled under IPV6_MIN_MTU.
2950 		 * Stop IPv6 on this interface.
2951 		 */
2952 
2953 	case NETDEV_DOWN:
2954 	case NETDEV_UNREGISTER:
2955 		/*
2956 		 *	Remove all addresses from this interface.
2957 		 */
2958 		addrconf_ifdown(dev, event != NETDEV_DOWN);
2959 		break;
2960 
2961 	case NETDEV_CHANGENAME:
2962 		if (idev) {
2963 			snmp6_unregister_dev(idev);
2964 			addrconf_sysctl_unregister(idev);
2965 			addrconf_sysctl_register(idev);
2966 			err = snmp6_register_dev(idev);
2967 			if (err)
2968 				return notifier_from_errno(err);
2969 		}
2970 		break;
2971 
2972 	case NETDEV_PRE_TYPE_CHANGE:
2973 	case NETDEV_POST_TYPE_CHANGE:
2974 		addrconf_type_change(dev, event);
2975 		break;
2976 	}
2977 
2978 	return NOTIFY_OK;
2979 }
2980 
2981 /*
2982  *	addrconf module should be notified of a device going up
2983  */
2984 static struct notifier_block ipv6_dev_notf = {
2985 	.notifier_call = addrconf_notify,
2986 };
2987 
2988 static void addrconf_type_change(struct net_device *dev, unsigned long event)
2989 {
2990 	struct inet6_dev *idev;
2991 	ASSERT_RTNL();
2992 
2993 	idev = __in6_dev_get(dev);
2994 
2995 	if (event == NETDEV_POST_TYPE_CHANGE)
2996 		ipv6_mc_remap(idev);
2997 	else if (event == NETDEV_PRE_TYPE_CHANGE)
2998 		ipv6_mc_unmap(idev);
2999 }
3000 
3001 static int addrconf_ifdown(struct net_device *dev, int how)
3002 {
3003 	struct net *net = dev_net(dev);
3004 	struct inet6_dev *idev;
3005 	struct inet6_ifaddr *ifa;
3006 	int state, i;
3007 
3008 	ASSERT_RTNL();
3009 
3010 	rt6_ifdown(net, dev);
3011 	neigh_ifdown(&nd_tbl, dev);
3012 
3013 	idev = __in6_dev_get(dev);
3014 	if (idev == NULL)
3015 		return -ENODEV;
3016 
3017 	/*
3018 	 * Step 1: remove reference to ipv6 device from parent device.
3019 	 *	   Do not dev_put!
3020 	 */
3021 	if (how) {
3022 		idev->dead = 1;
3023 
3024 		/* protected by rtnl_lock */
3025 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
3026 
3027 		/* Step 1.5: remove snmp6 entry */
3028 		snmp6_unregister_dev(idev);
3029 
3030 	}
3031 
3032 	/* Step 2: clear hash table */
3033 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3034 		struct hlist_head *h = &inet6_addr_lst[i];
3035 
3036 		spin_lock_bh(&addrconf_hash_lock);
3037 	restart:
3038 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
3039 			if (ifa->idev == idev) {
3040 				hlist_del_init_rcu(&ifa->addr_lst);
3041 				addrconf_del_timer(ifa);
3042 				goto restart;
3043 			}
3044 		}
3045 		spin_unlock_bh(&addrconf_hash_lock);
3046 	}
3047 
3048 	write_lock_bh(&idev->lock);
3049 
3050 	/* Step 2: clear flags for stateless addrconf */
3051 	if (!how)
3052 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3053 
3054 #ifdef CONFIG_IPV6_PRIVACY
3055 	if (how && del_timer(&idev->regen_timer))
3056 		in6_dev_put(idev);
3057 
3058 	/* Step 3: clear tempaddr list */
3059 	while (!list_empty(&idev->tempaddr_list)) {
3060 		ifa = list_first_entry(&idev->tempaddr_list,
3061 				       struct inet6_ifaddr, tmp_list);
3062 		list_del(&ifa->tmp_list);
3063 		write_unlock_bh(&idev->lock);
3064 		spin_lock_bh(&ifa->lock);
3065 
3066 		if (ifa->ifpub) {
3067 			in6_ifa_put(ifa->ifpub);
3068 			ifa->ifpub = NULL;
3069 		}
3070 		spin_unlock_bh(&ifa->lock);
3071 		in6_ifa_put(ifa);
3072 		write_lock_bh(&idev->lock);
3073 	}
3074 #endif
3075 
3076 	while (!list_empty(&idev->addr_list)) {
3077 		ifa = list_first_entry(&idev->addr_list,
3078 				       struct inet6_ifaddr, if_list);
3079 		addrconf_del_timer(ifa);
3080 
3081 		list_del(&ifa->if_list);
3082 
3083 		write_unlock_bh(&idev->lock);
3084 
3085 		spin_lock_bh(&ifa->state_lock);
3086 		state = ifa->state;
3087 		ifa->state = INET6_IFADDR_STATE_DEAD;
3088 		spin_unlock_bh(&ifa->state_lock);
3089 
3090 		if (state != INET6_IFADDR_STATE_DEAD) {
3091 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
3092 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
3093 		}
3094 		in6_ifa_put(ifa);
3095 
3096 		write_lock_bh(&idev->lock);
3097 	}
3098 
3099 	write_unlock_bh(&idev->lock);
3100 
3101 	/* Step 5: Discard multicast list */
3102 	if (how)
3103 		ipv6_mc_destroy_dev(idev);
3104 	else
3105 		ipv6_mc_down(idev);
3106 
3107 	idev->tstamp = jiffies;
3108 
3109 	/* Last: Shot the device (if unregistered) */
3110 	if (how) {
3111 		addrconf_sysctl_unregister(idev);
3112 		neigh_parms_release(&nd_tbl, idev->nd_parms);
3113 		neigh_ifdown(&nd_tbl, dev);
3114 		in6_dev_put(idev);
3115 	}
3116 	return 0;
3117 }
3118 
3119 static void addrconf_rs_timer(unsigned long data)
3120 {
3121 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *) data;
3122 	struct inet6_dev *idev = ifp->idev;
3123 
3124 	read_lock(&idev->lock);
3125 	if (idev->dead || !(idev->if_flags & IF_READY))
3126 		goto out;
3127 
3128 	if (!ipv6_accept_ra(idev))
3129 		goto out;
3130 
3131 	/* Announcement received after solicitation was sent */
3132 	if (idev->if_flags & IF_RA_RCVD)
3133 		goto out;
3134 
3135 	spin_lock(&ifp->lock);
3136 	if (ifp->probes++ < idev->cnf.rtr_solicits) {
3137 		/* The wait after the last probe can be shorter */
3138 		addrconf_mod_timer(ifp, AC_RS,
3139 				   (ifp->probes == idev->cnf.rtr_solicits) ?
3140 				   idev->cnf.rtr_solicit_delay :
3141 				   idev->cnf.rtr_solicit_interval);
3142 		spin_unlock(&ifp->lock);
3143 
3144 		ndisc_send_rs(idev->dev, &ifp->addr, &in6addr_linklocal_allrouters);
3145 	} else {
3146 		spin_unlock(&ifp->lock);
3147 		/*
3148 		 * Note: we do not support deprecated "all on-link"
3149 		 * assumption any longer.
3150 		 */
3151 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
3152 	}
3153 
3154 out:
3155 	read_unlock(&idev->lock);
3156 	in6_ifa_put(ifp);
3157 }
3158 
3159 /*
3160  *	Duplicate Address Detection
3161  */
3162 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
3163 {
3164 	unsigned long rand_num;
3165 	struct inet6_dev *idev = ifp->idev;
3166 
3167 	if (ifp->flags & IFA_F_OPTIMISTIC)
3168 		rand_num = 0;
3169 	else
3170 		rand_num = net_random() % (idev->cnf.rtr_solicit_delay ? : 1);
3171 
3172 	ifp->probes = idev->cnf.dad_transmits;
3173 	addrconf_mod_timer(ifp, AC_DAD, rand_num);
3174 }
3175 
3176 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
3177 {
3178 	struct inet6_dev *idev = ifp->idev;
3179 	struct net_device *dev = idev->dev;
3180 
3181 	addrconf_join_solict(dev, &ifp->addr);
3182 
3183 	net_srandom(ifp->addr.s6_addr32[3]);
3184 
3185 	read_lock_bh(&idev->lock);
3186 	spin_lock(&ifp->lock);
3187 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
3188 		goto out;
3189 
3190 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
3191 	    idev->cnf.accept_dad < 1 ||
3192 	    !(ifp->flags&IFA_F_TENTATIVE) ||
3193 	    ifp->flags & IFA_F_NODAD) {
3194 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3195 		spin_unlock(&ifp->lock);
3196 		read_unlock_bh(&idev->lock);
3197 
3198 		addrconf_dad_completed(ifp);
3199 		return;
3200 	}
3201 
3202 	if (!(idev->if_flags & IF_READY)) {
3203 		spin_unlock(&ifp->lock);
3204 		read_unlock_bh(&idev->lock);
3205 		/*
3206 		 * If the device is not ready:
3207 		 * - keep it tentative if it is a permanent address.
3208 		 * - otherwise, kill it.
3209 		 */
3210 		in6_ifa_hold(ifp);
3211 		addrconf_dad_stop(ifp, 0);
3212 		return;
3213 	}
3214 
3215 	/*
3216 	 * Optimistic nodes can start receiving
3217 	 * Frames right away
3218 	 */
3219 	if (ifp->flags & IFA_F_OPTIMISTIC)
3220 		ip6_ins_rt(ifp->rt);
3221 
3222 	addrconf_dad_kick(ifp);
3223 out:
3224 	spin_unlock(&ifp->lock);
3225 	read_unlock_bh(&idev->lock);
3226 }
3227 
3228 static void addrconf_dad_timer(unsigned long data)
3229 {
3230 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *) data;
3231 	struct inet6_dev *idev = ifp->idev;
3232 	struct in6_addr mcaddr;
3233 
3234 	if (!ifp->probes && addrconf_dad_end(ifp))
3235 		goto out;
3236 
3237 	read_lock(&idev->lock);
3238 	if (idev->dead || !(idev->if_flags & IF_READY)) {
3239 		read_unlock(&idev->lock);
3240 		goto out;
3241 	}
3242 
3243 	spin_lock(&ifp->lock);
3244 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
3245 		spin_unlock(&ifp->lock);
3246 		read_unlock(&idev->lock);
3247 		goto out;
3248 	}
3249 
3250 	if (ifp->probes == 0) {
3251 		/*
3252 		 * DAD was successful
3253 		 */
3254 
3255 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3256 		spin_unlock(&ifp->lock);
3257 		read_unlock(&idev->lock);
3258 
3259 		addrconf_dad_completed(ifp);
3260 
3261 		goto out;
3262 	}
3263 
3264 	ifp->probes--;
3265 	addrconf_mod_timer(ifp, AC_DAD, ifp->idev->nd_parms->retrans_time);
3266 	spin_unlock(&ifp->lock);
3267 	read_unlock(&idev->lock);
3268 
3269 	/* send a neighbour solicitation for our addr */
3270 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
3271 	ndisc_send_ns(ifp->idev->dev, NULL, &ifp->addr, &mcaddr, &in6addr_any);
3272 out:
3273 	in6_ifa_put(ifp);
3274 }
3275 
3276 static void addrconf_dad_completed(struct inet6_ifaddr *ifp)
3277 {
3278 	struct net_device *dev = ifp->idev->dev;
3279 
3280 	/*
3281 	 *	Configure the address for reception. Now it is valid.
3282 	 */
3283 
3284 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
3285 
3286 	/* If added prefix is link local and we are prepared to process
3287 	   router advertisements, start sending router solicitations.
3288 	 */
3289 
3290 	if (ipv6_accept_ra(ifp->idev) &&
3291 	    ifp->idev->cnf.rtr_solicits > 0 &&
3292 	    (dev->flags&IFF_LOOPBACK) == 0 &&
3293 	    (ipv6_addr_type(&ifp->addr) & IPV6_ADDR_LINKLOCAL)) {
3294 		/*
3295 		 *	If a host as already performed a random delay
3296 		 *	[...] as part of DAD [...] there is no need
3297 		 *	to delay again before sending the first RS
3298 		 */
3299 		ndisc_send_rs(ifp->idev->dev, &ifp->addr, &in6addr_linklocal_allrouters);
3300 
3301 		spin_lock_bh(&ifp->lock);
3302 		ifp->probes = 1;
3303 		ifp->idev->if_flags |= IF_RS_SENT;
3304 		addrconf_mod_timer(ifp, AC_RS, ifp->idev->cnf.rtr_solicit_interval);
3305 		spin_unlock_bh(&ifp->lock);
3306 	}
3307 }
3308 
3309 static void addrconf_dad_run(struct inet6_dev *idev)
3310 {
3311 	struct inet6_ifaddr *ifp;
3312 
3313 	read_lock_bh(&idev->lock);
3314 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
3315 		spin_lock(&ifp->lock);
3316 		if (ifp->flags & IFA_F_TENTATIVE &&
3317 		    ifp->state == INET6_IFADDR_STATE_DAD)
3318 			addrconf_dad_kick(ifp);
3319 		spin_unlock(&ifp->lock);
3320 	}
3321 	read_unlock_bh(&idev->lock);
3322 }
3323 
3324 #ifdef CONFIG_PROC_FS
3325 struct if6_iter_state {
3326 	struct seq_net_private p;
3327 	int bucket;
3328 	int offset;
3329 };
3330 
3331 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
3332 {
3333 	struct inet6_ifaddr *ifa = NULL;
3334 	struct if6_iter_state *state = seq->private;
3335 	struct net *net = seq_file_net(seq);
3336 	int p = 0;
3337 
3338 	/* initial bucket if pos is 0 */
3339 	if (pos == 0) {
3340 		state->bucket = 0;
3341 		state->offset = 0;
3342 	}
3343 
3344 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
3345 		hlist_for_each_entry_rcu_bh(ifa, &inet6_addr_lst[state->bucket],
3346 					 addr_lst) {
3347 			if (!net_eq(dev_net(ifa->idev->dev), net))
3348 				continue;
3349 			/* sync with offset */
3350 			if (p < state->offset) {
3351 				p++;
3352 				continue;
3353 			}
3354 			state->offset++;
3355 			return ifa;
3356 		}
3357 
3358 		/* prepare for next bucket */
3359 		state->offset = 0;
3360 		p = 0;
3361 	}
3362 	return NULL;
3363 }
3364 
3365 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
3366 					 struct inet6_ifaddr *ifa)
3367 {
3368 	struct if6_iter_state *state = seq->private;
3369 	struct net *net = seq_file_net(seq);
3370 
3371 	hlist_for_each_entry_continue_rcu_bh(ifa, addr_lst) {
3372 		if (!net_eq(dev_net(ifa->idev->dev), net))
3373 			continue;
3374 		state->offset++;
3375 		return ifa;
3376 	}
3377 
3378 	while (++state->bucket < IN6_ADDR_HSIZE) {
3379 		state->offset = 0;
3380 		hlist_for_each_entry_rcu_bh(ifa,
3381 				     &inet6_addr_lst[state->bucket], addr_lst) {
3382 			if (!net_eq(dev_net(ifa->idev->dev), net))
3383 				continue;
3384 			state->offset++;
3385 			return ifa;
3386 		}
3387 	}
3388 
3389 	return NULL;
3390 }
3391 
3392 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
3393 	__acquires(rcu_bh)
3394 {
3395 	rcu_read_lock_bh();
3396 	return if6_get_first(seq, *pos);
3397 }
3398 
3399 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3400 {
3401 	struct inet6_ifaddr *ifa;
3402 
3403 	ifa = if6_get_next(seq, v);
3404 	++*pos;
3405 	return ifa;
3406 }
3407 
3408 static void if6_seq_stop(struct seq_file *seq, void *v)
3409 	__releases(rcu_bh)
3410 {
3411 	rcu_read_unlock_bh();
3412 }
3413 
3414 static int if6_seq_show(struct seq_file *seq, void *v)
3415 {
3416 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
3417 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
3418 		   &ifp->addr,
3419 		   ifp->idev->dev->ifindex,
3420 		   ifp->prefix_len,
3421 		   ifp->scope,
3422 		   ifp->flags,
3423 		   ifp->idev->dev->name);
3424 	return 0;
3425 }
3426 
3427 static const struct seq_operations if6_seq_ops = {
3428 	.start	= if6_seq_start,
3429 	.next	= if6_seq_next,
3430 	.show	= if6_seq_show,
3431 	.stop	= if6_seq_stop,
3432 };
3433 
3434 static int if6_seq_open(struct inode *inode, struct file *file)
3435 {
3436 	return seq_open_net(inode, file, &if6_seq_ops,
3437 			    sizeof(struct if6_iter_state));
3438 }
3439 
3440 static const struct file_operations if6_fops = {
3441 	.owner		= THIS_MODULE,
3442 	.open		= if6_seq_open,
3443 	.read		= seq_read,
3444 	.llseek		= seq_lseek,
3445 	.release	= seq_release_net,
3446 };
3447 
3448 static int __net_init if6_proc_net_init(struct net *net)
3449 {
3450 	if (!proc_create("if_inet6", S_IRUGO, net->proc_net, &if6_fops))
3451 		return -ENOMEM;
3452 	return 0;
3453 }
3454 
3455 static void __net_exit if6_proc_net_exit(struct net *net)
3456 {
3457 	remove_proc_entry("if_inet6", net->proc_net);
3458 }
3459 
3460 static struct pernet_operations if6_proc_net_ops = {
3461        .init = if6_proc_net_init,
3462        .exit = if6_proc_net_exit,
3463 };
3464 
3465 int __init if6_proc_init(void)
3466 {
3467 	return register_pernet_subsys(&if6_proc_net_ops);
3468 }
3469 
3470 void if6_proc_exit(void)
3471 {
3472 	unregister_pernet_subsys(&if6_proc_net_ops);
3473 }
3474 #endif	/* CONFIG_PROC_FS */
3475 
3476 #if IS_ENABLED(CONFIG_IPV6_MIP6)
3477 /* Check if address is a home address configured on any interface. */
3478 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
3479 {
3480 	int ret = 0;
3481 	struct inet6_ifaddr *ifp = NULL;
3482 	unsigned int hash = inet6_addr_hash(addr);
3483 
3484 	rcu_read_lock_bh();
3485 	hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[hash], addr_lst) {
3486 		if (!net_eq(dev_net(ifp->idev->dev), net))
3487 			continue;
3488 		if (ipv6_addr_equal(&ifp->addr, addr) &&
3489 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
3490 			ret = 1;
3491 			break;
3492 		}
3493 	}
3494 	rcu_read_unlock_bh();
3495 	return ret;
3496 }
3497 #endif
3498 
3499 /*
3500  *	Periodic address status verification
3501  */
3502 
3503 static void addrconf_verify(unsigned long foo)
3504 {
3505 	unsigned long now, next, next_sec, next_sched;
3506 	struct inet6_ifaddr *ifp;
3507 	int i;
3508 
3509 	rcu_read_lock_bh();
3510 	spin_lock(&addrconf_verify_lock);
3511 	now = jiffies;
3512 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
3513 
3514 	del_timer(&addr_chk_timer);
3515 
3516 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3517 restart:
3518 		hlist_for_each_entry_rcu_bh(ifp,
3519 					 &inet6_addr_lst[i], addr_lst) {
3520 			unsigned long age;
3521 
3522 			if (ifp->flags & IFA_F_PERMANENT)
3523 				continue;
3524 
3525 			spin_lock(&ifp->lock);
3526 			/* We try to batch several events at once. */
3527 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
3528 
3529 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
3530 			    age >= ifp->valid_lft) {
3531 				spin_unlock(&ifp->lock);
3532 				in6_ifa_hold(ifp);
3533 				ipv6_del_addr(ifp);
3534 				goto restart;
3535 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
3536 				spin_unlock(&ifp->lock);
3537 				continue;
3538 			} else if (age >= ifp->prefered_lft) {
3539 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
3540 				int deprecate = 0;
3541 
3542 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
3543 					deprecate = 1;
3544 					ifp->flags |= IFA_F_DEPRECATED;
3545 				}
3546 
3547 				if (time_before(ifp->tstamp + ifp->valid_lft * HZ, next))
3548 					next = ifp->tstamp + ifp->valid_lft * HZ;
3549 
3550 				spin_unlock(&ifp->lock);
3551 
3552 				if (deprecate) {
3553 					in6_ifa_hold(ifp);
3554 
3555 					ipv6_ifa_notify(0, ifp);
3556 					in6_ifa_put(ifp);
3557 					goto restart;
3558 				}
3559 #ifdef CONFIG_IPV6_PRIVACY
3560 			} else if ((ifp->flags&IFA_F_TEMPORARY) &&
3561 				   !(ifp->flags&IFA_F_TENTATIVE)) {
3562 				unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
3563 					ifp->idev->cnf.dad_transmits *
3564 					ifp->idev->nd_parms->retrans_time / HZ;
3565 
3566 				if (age >= ifp->prefered_lft - regen_advance) {
3567 					struct inet6_ifaddr *ifpub = ifp->ifpub;
3568 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
3569 						next = ifp->tstamp + ifp->prefered_lft * HZ;
3570 					if (!ifp->regen_count && ifpub) {
3571 						ifp->regen_count++;
3572 						in6_ifa_hold(ifp);
3573 						in6_ifa_hold(ifpub);
3574 						spin_unlock(&ifp->lock);
3575 
3576 						spin_lock(&ifpub->lock);
3577 						ifpub->regen_count = 0;
3578 						spin_unlock(&ifpub->lock);
3579 						ipv6_create_tempaddr(ifpub, ifp);
3580 						in6_ifa_put(ifpub);
3581 						in6_ifa_put(ifp);
3582 						goto restart;
3583 					}
3584 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
3585 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
3586 				spin_unlock(&ifp->lock);
3587 #endif
3588 			} else {
3589 				/* ifp->prefered_lft <= ifp->valid_lft */
3590 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
3591 					next = ifp->tstamp + ifp->prefered_lft * HZ;
3592 				spin_unlock(&ifp->lock);
3593 			}
3594 		}
3595 	}
3596 
3597 	next_sec = round_jiffies_up(next);
3598 	next_sched = next;
3599 
3600 	/* If rounded timeout is accurate enough, accept it. */
3601 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
3602 		next_sched = next_sec;
3603 
3604 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
3605 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
3606 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
3607 
3608 	ADBG((KERN_DEBUG "now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
3609 	      now, next, next_sec, next_sched));
3610 
3611 	addr_chk_timer.expires = next_sched;
3612 	add_timer(&addr_chk_timer);
3613 	spin_unlock(&addrconf_verify_lock);
3614 	rcu_read_unlock_bh();
3615 }
3616 
3617 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
3618 				     struct in6_addr **peer_pfx)
3619 {
3620 	struct in6_addr *pfx = NULL;
3621 
3622 	*peer_pfx = NULL;
3623 
3624 	if (addr)
3625 		pfx = nla_data(addr);
3626 
3627 	if (local) {
3628 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
3629 			*peer_pfx = pfx;
3630 		pfx = nla_data(local);
3631 	}
3632 
3633 	return pfx;
3634 }
3635 
3636 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
3637 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
3638 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
3639 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
3640 };
3641 
3642 static int
3643 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh)
3644 {
3645 	struct net *net = sock_net(skb->sk);
3646 	struct ifaddrmsg *ifm;
3647 	struct nlattr *tb[IFA_MAX+1];
3648 	struct in6_addr *pfx, *peer_pfx;
3649 	int err;
3650 
3651 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
3652 	if (err < 0)
3653 		return err;
3654 
3655 	ifm = nlmsg_data(nlh);
3656 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
3657 	if (pfx == NULL)
3658 		return -EINVAL;
3659 
3660 	return inet6_addr_del(net, ifm->ifa_index, pfx, ifm->ifa_prefixlen);
3661 }
3662 
3663 static int inet6_addr_modify(struct inet6_ifaddr *ifp, u8 ifa_flags,
3664 			     u32 prefered_lft, u32 valid_lft)
3665 {
3666 	u32 flags;
3667 	clock_t expires;
3668 	unsigned long timeout;
3669 
3670 	if (!valid_lft || (prefered_lft > valid_lft))
3671 		return -EINVAL;
3672 
3673 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
3674 	if (addrconf_finite_timeout(timeout)) {
3675 		expires = jiffies_to_clock_t(timeout * HZ);
3676 		valid_lft = timeout;
3677 		flags = RTF_EXPIRES;
3678 	} else {
3679 		expires = 0;
3680 		flags = 0;
3681 		ifa_flags |= IFA_F_PERMANENT;
3682 	}
3683 
3684 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
3685 	if (addrconf_finite_timeout(timeout)) {
3686 		if (timeout == 0)
3687 			ifa_flags |= IFA_F_DEPRECATED;
3688 		prefered_lft = timeout;
3689 	}
3690 
3691 	spin_lock_bh(&ifp->lock);
3692 	ifp->flags = (ifp->flags & ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD | IFA_F_HOMEADDRESS)) | ifa_flags;
3693 	ifp->tstamp = jiffies;
3694 	ifp->valid_lft = valid_lft;
3695 	ifp->prefered_lft = prefered_lft;
3696 
3697 	spin_unlock_bh(&ifp->lock);
3698 	if (!(ifp->flags&IFA_F_TENTATIVE))
3699 		ipv6_ifa_notify(0, ifp);
3700 
3701 	addrconf_prefix_route(&ifp->addr, ifp->prefix_len, ifp->idev->dev,
3702 			      expires, flags);
3703 	addrconf_verify(0);
3704 
3705 	return 0;
3706 }
3707 
3708 static int
3709 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh)
3710 {
3711 	struct net *net = sock_net(skb->sk);
3712 	struct ifaddrmsg *ifm;
3713 	struct nlattr *tb[IFA_MAX+1];
3714 	struct in6_addr *pfx, *peer_pfx;
3715 	struct inet6_ifaddr *ifa;
3716 	struct net_device *dev;
3717 	u32 valid_lft = INFINITY_LIFE_TIME, preferred_lft = INFINITY_LIFE_TIME;
3718 	u8 ifa_flags;
3719 	int err;
3720 
3721 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
3722 	if (err < 0)
3723 		return err;
3724 
3725 	ifm = nlmsg_data(nlh);
3726 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
3727 	if (pfx == NULL)
3728 		return -EINVAL;
3729 
3730 	if (tb[IFA_CACHEINFO]) {
3731 		struct ifa_cacheinfo *ci;
3732 
3733 		ci = nla_data(tb[IFA_CACHEINFO]);
3734 		valid_lft = ci->ifa_valid;
3735 		preferred_lft = ci->ifa_prefered;
3736 	} else {
3737 		preferred_lft = INFINITY_LIFE_TIME;
3738 		valid_lft = INFINITY_LIFE_TIME;
3739 	}
3740 
3741 	dev =  __dev_get_by_index(net, ifm->ifa_index);
3742 	if (dev == NULL)
3743 		return -ENODEV;
3744 
3745 	/* We ignore other flags so far. */
3746 	ifa_flags = ifm->ifa_flags & (IFA_F_NODAD | IFA_F_HOMEADDRESS);
3747 
3748 	ifa = ipv6_get_ifaddr(net, pfx, dev, 1);
3749 	if (ifa == NULL) {
3750 		/*
3751 		 * It would be best to check for !NLM_F_CREATE here but
3752 		 * userspace alreay relies on not having to provide this.
3753 		 */
3754 		return inet6_addr_add(net, ifm->ifa_index, pfx, peer_pfx,
3755 				      ifm->ifa_prefixlen, ifa_flags,
3756 				      preferred_lft, valid_lft);
3757 	}
3758 
3759 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
3760 	    !(nlh->nlmsg_flags & NLM_F_REPLACE))
3761 		err = -EEXIST;
3762 	else
3763 		err = inet6_addr_modify(ifa, ifa_flags, preferred_lft, valid_lft);
3764 
3765 	in6_ifa_put(ifa);
3766 
3767 	return err;
3768 }
3769 
3770 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u8 flags,
3771 			  u8 scope, int ifindex)
3772 {
3773 	struct ifaddrmsg *ifm;
3774 
3775 	ifm = nlmsg_data(nlh);
3776 	ifm->ifa_family = AF_INET6;
3777 	ifm->ifa_prefixlen = prefixlen;
3778 	ifm->ifa_flags = flags;
3779 	ifm->ifa_scope = scope;
3780 	ifm->ifa_index = ifindex;
3781 }
3782 
3783 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
3784 			 unsigned long tstamp, u32 preferred, u32 valid)
3785 {
3786 	struct ifa_cacheinfo ci;
3787 
3788 	ci.cstamp = cstamp_delta(cstamp);
3789 	ci.tstamp = cstamp_delta(tstamp);
3790 	ci.ifa_prefered = preferred;
3791 	ci.ifa_valid = valid;
3792 
3793 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
3794 }
3795 
3796 static inline int rt_scope(int ifa_scope)
3797 {
3798 	if (ifa_scope & IFA_HOST)
3799 		return RT_SCOPE_HOST;
3800 	else if (ifa_scope & IFA_LINK)
3801 		return RT_SCOPE_LINK;
3802 	else if (ifa_scope & IFA_SITE)
3803 		return RT_SCOPE_SITE;
3804 	else
3805 		return RT_SCOPE_UNIVERSE;
3806 }
3807 
3808 static inline int inet6_ifaddr_msgsize(void)
3809 {
3810 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
3811 	       + nla_total_size(16) /* IFA_LOCAL */
3812 	       + nla_total_size(16) /* IFA_ADDRESS */
3813 	       + nla_total_size(sizeof(struct ifa_cacheinfo));
3814 }
3815 
3816 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
3817 			     u32 portid, u32 seq, int event, unsigned int flags)
3818 {
3819 	struct nlmsghdr  *nlh;
3820 	u32 preferred, valid;
3821 
3822 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
3823 	if (nlh == NULL)
3824 		return -EMSGSIZE;
3825 
3826 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
3827 		      ifa->idev->dev->ifindex);
3828 
3829 	if (!(ifa->flags&IFA_F_PERMANENT)) {
3830 		preferred = ifa->prefered_lft;
3831 		valid = ifa->valid_lft;
3832 		if (preferred != INFINITY_LIFE_TIME) {
3833 			long tval = (jiffies - ifa->tstamp)/HZ;
3834 			if (preferred > tval)
3835 				preferred -= tval;
3836 			else
3837 				preferred = 0;
3838 			if (valid != INFINITY_LIFE_TIME) {
3839 				if (valid > tval)
3840 					valid -= tval;
3841 				else
3842 					valid = 0;
3843 			}
3844 		}
3845 	} else {
3846 		preferred = INFINITY_LIFE_TIME;
3847 		valid = INFINITY_LIFE_TIME;
3848 	}
3849 
3850 	if (!ipv6_addr_any(&ifa->peer_addr)) {
3851 		if (nla_put(skb, IFA_LOCAL, 16, &ifa->addr) < 0 ||
3852 		    nla_put(skb, IFA_ADDRESS, 16, &ifa->peer_addr) < 0)
3853 			goto error;
3854 	} else
3855 		if (nla_put(skb, IFA_ADDRESS, 16, &ifa->addr) < 0)
3856 			goto error;
3857 
3858 	if (put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0)
3859 		goto error;
3860 
3861 	return nlmsg_end(skb, nlh);
3862 
3863 error:
3864 	nlmsg_cancel(skb, nlh);
3865 	return -EMSGSIZE;
3866 }
3867 
3868 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
3869 				u32 portid, u32 seq, int event, u16 flags)
3870 {
3871 	struct nlmsghdr  *nlh;
3872 	u8 scope = RT_SCOPE_UNIVERSE;
3873 	int ifindex = ifmca->idev->dev->ifindex;
3874 
3875 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
3876 		scope = RT_SCOPE_SITE;
3877 
3878 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
3879 	if (nlh == NULL)
3880 		return -EMSGSIZE;
3881 
3882 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
3883 	if (nla_put(skb, IFA_MULTICAST, 16, &ifmca->mca_addr) < 0 ||
3884 	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
3885 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
3886 		nlmsg_cancel(skb, nlh);
3887 		return -EMSGSIZE;
3888 	}
3889 
3890 	return nlmsg_end(skb, nlh);
3891 }
3892 
3893 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
3894 				u32 portid, u32 seq, int event, unsigned int flags)
3895 {
3896 	struct nlmsghdr  *nlh;
3897 	u8 scope = RT_SCOPE_UNIVERSE;
3898 	int ifindex = ifaca->aca_idev->dev->ifindex;
3899 
3900 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
3901 		scope = RT_SCOPE_SITE;
3902 
3903 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
3904 	if (nlh == NULL)
3905 		return -EMSGSIZE;
3906 
3907 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
3908 	if (nla_put(skb, IFA_ANYCAST, 16, &ifaca->aca_addr) < 0 ||
3909 	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
3910 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
3911 		nlmsg_cancel(skb, nlh);
3912 		return -EMSGSIZE;
3913 	}
3914 
3915 	return nlmsg_end(skb, nlh);
3916 }
3917 
3918 enum addr_type_t {
3919 	UNICAST_ADDR,
3920 	MULTICAST_ADDR,
3921 	ANYCAST_ADDR,
3922 };
3923 
3924 /* called with rcu_read_lock() */
3925 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
3926 			  struct netlink_callback *cb, enum addr_type_t type,
3927 			  int s_ip_idx, int *p_ip_idx)
3928 {
3929 	struct ifmcaddr6 *ifmca;
3930 	struct ifacaddr6 *ifaca;
3931 	int err = 1;
3932 	int ip_idx = *p_ip_idx;
3933 
3934 	read_lock_bh(&idev->lock);
3935 	switch (type) {
3936 	case UNICAST_ADDR: {
3937 		struct inet6_ifaddr *ifa;
3938 
3939 		/* unicast address incl. temp addr */
3940 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
3941 			if (++ip_idx < s_ip_idx)
3942 				continue;
3943 			err = inet6_fill_ifaddr(skb, ifa,
3944 						NETLINK_CB(cb->skb).portid,
3945 						cb->nlh->nlmsg_seq,
3946 						RTM_NEWADDR,
3947 						NLM_F_MULTI);
3948 			if (err <= 0)
3949 				break;
3950 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
3951 		}
3952 		break;
3953 	}
3954 	case MULTICAST_ADDR:
3955 		/* multicast address */
3956 		for (ifmca = idev->mc_list; ifmca;
3957 		     ifmca = ifmca->next, ip_idx++) {
3958 			if (ip_idx < s_ip_idx)
3959 				continue;
3960 			err = inet6_fill_ifmcaddr(skb, ifmca,
3961 						  NETLINK_CB(cb->skb).portid,
3962 						  cb->nlh->nlmsg_seq,
3963 						  RTM_GETMULTICAST,
3964 						  NLM_F_MULTI);
3965 			if (err <= 0)
3966 				break;
3967 		}
3968 		break;
3969 	case ANYCAST_ADDR:
3970 		/* anycast address */
3971 		for (ifaca = idev->ac_list; ifaca;
3972 		     ifaca = ifaca->aca_next, ip_idx++) {
3973 			if (ip_idx < s_ip_idx)
3974 				continue;
3975 			err = inet6_fill_ifacaddr(skb, ifaca,
3976 						  NETLINK_CB(cb->skb).portid,
3977 						  cb->nlh->nlmsg_seq,
3978 						  RTM_GETANYCAST,
3979 						  NLM_F_MULTI);
3980 			if (err <= 0)
3981 				break;
3982 		}
3983 		break;
3984 	default:
3985 		break;
3986 	}
3987 	read_unlock_bh(&idev->lock);
3988 	*p_ip_idx = ip_idx;
3989 	return err;
3990 }
3991 
3992 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
3993 			   enum addr_type_t type)
3994 {
3995 	struct net *net = sock_net(skb->sk);
3996 	int h, s_h;
3997 	int idx, ip_idx;
3998 	int s_idx, s_ip_idx;
3999 	struct net_device *dev;
4000 	struct inet6_dev *idev;
4001 	struct hlist_head *head;
4002 
4003 	s_h = cb->args[0];
4004 	s_idx = idx = cb->args[1];
4005 	s_ip_idx = ip_idx = cb->args[2];
4006 
4007 	rcu_read_lock();
4008 	cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^ net->dev_base_seq;
4009 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
4010 		idx = 0;
4011 		head = &net->dev_index_head[h];
4012 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
4013 			if (idx < s_idx)
4014 				goto cont;
4015 			if (h > s_h || idx > s_idx)
4016 				s_ip_idx = 0;
4017 			ip_idx = 0;
4018 			idev = __in6_dev_get(dev);
4019 			if (!idev)
4020 				goto cont;
4021 
4022 			if (in6_dump_addrs(idev, skb, cb, type,
4023 					   s_ip_idx, &ip_idx) <= 0)
4024 				goto done;
4025 cont:
4026 			idx++;
4027 		}
4028 	}
4029 done:
4030 	rcu_read_unlock();
4031 	cb->args[0] = h;
4032 	cb->args[1] = idx;
4033 	cb->args[2] = ip_idx;
4034 
4035 	return skb->len;
4036 }
4037 
4038 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
4039 {
4040 	enum addr_type_t type = UNICAST_ADDR;
4041 
4042 	return inet6_dump_addr(skb, cb, type);
4043 }
4044 
4045 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
4046 {
4047 	enum addr_type_t type = MULTICAST_ADDR;
4048 
4049 	return inet6_dump_addr(skb, cb, type);
4050 }
4051 
4052 
4053 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
4054 {
4055 	enum addr_type_t type = ANYCAST_ADDR;
4056 
4057 	return inet6_dump_addr(skb, cb, type);
4058 }
4059 
4060 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh)
4061 {
4062 	struct net *net = sock_net(in_skb->sk);
4063 	struct ifaddrmsg *ifm;
4064 	struct nlattr *tb[IFA_MAX+1];
4065 	struct in6_addr *addr = NULL, *peer;
4066 	struct net_device *dev = NULL;
4067 	struct inet6_ifaddr *ifa;
4068 	struct sk_buff *skb;
4069 	int err;
4070 
4071 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
4072 	if (err < 0)
4073 		goto errout;
4074 
4075 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
4076 	if (addr == NULL) {
4077 		err = -EINVAL;
4078 		goto errout;
4079 	}
4080 
4081 	ifm = nlmsg_data(nlh);
4082 	if (ifm->ifa_index)
4083 		dev = __dev_get_by_index(net, ifm->ifa_index);
4084 
4085 	ifa = ipv6_get_ifaddr(net, addr, dev, 1);
4086 	if (!ifa) {
4087 		err = -EADDRNOTAVAIL;
4088 		goto errout;
4089 	}
4090 
4091 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
4092 	if (!skb) {
4093 		err = -ENOBUFS;
4094 		goto errout_ifa;
4095 	}
4096 
4097 	err = inet6_fill_ifaddr(skb, ifa, NETLINK_CB(in_skb).portid,
4098 				nlh->nlmsg_seq, RTM_NEWADDR, 0);
4099 	if (err < 0) {
4100 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
4101 		WARN_ON(err == -EMSGSIZE);
4102 		kfree_skb(skb);
4103 		goto errout_ifa;
4104 	}
4105 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
4106 errout_ifa:
4107 	in6_ifa_put(ifa);
4108 errout:
4109 	return err;
4110 }
4111 
4112 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
4113 {
4114 	struct sk_buff *skb;
4115 	struct net *net = dev_net(ifa->idev->dev);
4116 	int err = -ENOBUFS;
4117 
4118 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
4119 	if (skb == NULL)
4120 		goto errout;
4121 
4122 	err = inet6_fill_ifaddr(skb, ifa, 0, 0, event, 0);
4123 	if (err < 0) {
4124 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
4125 		WARN_ON(err == -EMSGSIZE);
4126 		kfree_skb(skb);
4127 		goto errout;
4128 	}
4129 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
4130 	return;
4131 errout:
4132 	if (err < 0)
4133 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
4134 }
4135 
4136 static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
4137 				__s32 *array, int bytes)
4138 {
4139 	BUG_ON(bytes < (DEVCONF_MAX * 4));
4140 
4141 	memset(array, 0, bytes);
4142 	array[DEVCONF_FORWARDING] = cnf->forwarding;
4143 	array[DEVCONF_HOPLIMIT] = cnf->hop_limit;
4144 	array[DEVCONF_MTU6] = cnf->mtu6;
4145 	array[DEVCONF_ACCEPT_RA] = cnf->accept_ra;
4146 	array[DEVCONF_ACCEPT_REDIRECTS] = cnf->accept_redirects;
4147 	array[DEVCONF_AUTOCONF] = cnf->autoconf;
4148 	array[DEVCONF_DAD_TRANSMITS] = cnf->dad_transmits;
4149 	array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
4150 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
4151 		jiffies_to_msecs(cnf->rtr_solicit_interval);
4152 	array[DEVCONF_RTR_SOLICIT_DELAY] =
4153 		jiffies_to_msecs(cnf->rtr_solicit_delay);
4154 	array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;
4155 #ifdef CONFIG_IPV6_PRIVACY
4156 	array[DEVCONF_USE_TEMPADDR] = cnf->use_tempaddr;
4157 	array[DEVCONF_TEMP_VALID_LFT] = cnf->temp_valid_lft;
4158 	array[DEVCONF_TEMP_PREFERED_LFT] = cnf->temp_prefered_lft;
4159 	array[DEVCONF_REGEN_MAX_RETRY] = cnf->regen_max_retry;
4160 	array[DEVCONF_MAX_DESYNC_FACTOR] = cnf->max_desync_factor;
4161 #endif
4162 	array[DEVCONF_MAX_ADDRESSES] = cnf->max_addresses;
4163 	array[DEVCONF_ACCEPT_RA_DEFRTR] = cnf->accept_ra_defrtr;
4164 	array[DEVCONF_ACCEPT_RA_PINFO] = cnf->accept_ra_pinfo;
4165 #ifdef CONFIG_IPV6_ROUTER_PREF
4166 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = cnf->accept_ra_rtr_pref;
4167 	array[DEVCONF_RTR_PROBE_INTERVAL] =
4168 		jiffies_to_msecs(cnf->rtr_probe_interval);
4169 #ifdef CONFIG_IPV6_ROUTE_INFO
4170 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
4171 #endif
4172 #endif
4173 	array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
4174 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
4175 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
4176 	array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
4177 #endif
4178 #ifdef CONFIG_IPV6_MROUTE
4179 	array[DEVCONF_MC_FORWARDING] = cnf->mc_forwarding;
4180 #endif
4181 	array[DEVCONF_DISABLE_IPV6] = cnf->disable_ipv6;
4182 	array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad;
4183 	array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao;
4184 	array[DEVCONF_NDISC_NOTIFY] = cnf->ndisc_notify;
4185 }
4186 
4187 static inline size_t inet6_ifla6_size(void)
4188 {
4189 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
4190 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
4191 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
4192 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
4193 	     + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
4194 	     + nla_total_size(sizeof(struct in6_addr)); /* IFLA_INET6_TOKEN */
4195 }
4196 
4197 static inline size_t inet6_if_nlmsg_size(void)
4198 {
4199 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
4200 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
4201 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
4202 	       + nla_total_size(4) /* IFLA_MTU */
4203 	       + nla_total_size(4) /* IFLA_LINK */
4204 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
4205 }
4206 
4207 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
4208 				      int items, int bytes)
4209 {
4210 	int i;
4211 	int pad = bytes - sizeof(u64) * items;
4212 	BUG_ON(pad < 0);
4213 
4214 	/* Use put_unaligned() because stats may not be aligned for u64. */
4215 	put_unaligned(items, &stats[0]);
4216 	for (i = 1; i < items; i++)
4217 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
4218 
4219 	memset(&stats[items], 0, pad);
4220 }
4221 
4222 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu **mib,
4223 				      int items, int bytes, size_t syncpoff)
4224 {
4225 	int i;
4226 	int pad = bytes - sizeof(u64) * items;
4227 	BUG_ON(pad < 0);
4228 
4229 	/* Use put_unaligned() because stats may not be aligned for u64. */
4230 	put_unaligned(items, &stats[0]);
4231 	for (i = 1; i < items; i++)
4232 		put_unaligned(snmp_fold_field64(mib, i, syncpoff), &stats[i]);
4233 
4234 	memset(&stats[items], 0, pad);
4235 }
4236 
4237 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
4238 			     int bytes)
4239 {
4240 	switch (attrtype) {
4241 	case IFLA_INET6_STATS:
4242 		__snmp6_fill_stats64(stats, (void __percpu **)idev->stats.ipv6,
4243 				     IPSTATS_MIB_MAX, bytes, offsetof(struct ipstats_mib, syncp));
4244 		break;
4245 	case IFLA_INET6_ICMP6STATS:
4246 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, ICMP6_MIB_MAX, bytes);
4247 		break;
4248 	}
4249 }
4250 
4251 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev)
4252 {
4253 	struct nlattr *nla;
4254 	struct ifla_cacheinfo ci;
4255 
4256 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, idev->if_flags))
4257 		goto nla_put_failure;
4258 	ci.max_reasm_len = IPV6_MAXPLEN;
4259 	ci.tstamp = cstamp_delta(idev->tstamp);
4260 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
4261 	ci.retrans_time = jiffies_to_msecs(idev->nd_parms->retrans_time);
4262 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
4263 		goto nla_put_failure;
4264 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
4265 	if (nla == NULL)
4266 		goto nla_put_failure;
4267 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
4268 
4269 	/* XXX - MC not implemented */
4270 
4271 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
4272 	if (nla == NULL)
4273 		goto nla_put_failure;
4274 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
4275 
4276 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
4277 	if (nla == NULL)
4278 		goto nla_put_failure;
4279 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
4280 
4281 	nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
4282 	if (nla == NULL)
4283 		goto nla_put_failure;
4284 	read_lock_bh(&idev->lock);
4285 	memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
4286 	read_unlock_bh(&idev->lock);
4287 
4288 	return 0;
4289 
4290 nla_put_failure:
4291 	return -EMSGSIZE;
4292 }
4293 
4294 static size_t inet6_get_link_af_size(const struct net_device *dev)
4295 {
4296 	if (!__in6_dev_get(dev))
4297 		return 0;
4298 
4299 	return inet6_ifla6_size();
4300 }
4301 
4302 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev)
4303 {
4304 	struct inet6_dev *idev = __in6_dev_get(dev);
4305 
4306 	if (!idev)
4307 		return -ENODATA;
4308 
4309 	if (inet6_fill_ifla6_attrs(skb, idev) < 0)
4310 		return -EMSGSIZE;
4311 
4312 	return 0;
4313 }
4314 
4315 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token)
4316 {
4317 	struct inet6_ifaddr *ifp;
4318 	struct net_device *dev = idev->dev;
4319 	bool update_rs = false;
4320 
4321 	if (token == NULL)
4322 		return -EINVAL;
4323 	if (ipv6_addr_any(token))
4324 		return -EINVAL;
4325 	if (dev->flags & (IFF_LOOPBACK | IFF_NOARP))
4326 		return -EINVAL;
4327 	if (!ipv6_accept_ra(idev))
4328 		return -EINVAL;
4329 	if (idev->cnf.rtr_solicits <= 0)
4330 		return -EINVAL;
4331 
4332 	write_lock_bh(&idev->lock);
4333 
4334 	BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
4335 	memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
4336 
4337 	write_unlock_bh(&idev->lock);
4338 
4339 	if (!idev->dead && (idev->if_flags & IF_READY)) {
4340 		struct in6_addr ll_addr;
4341 
4342 		ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
4343 				IFA_F_OPTIMISTIC);
4344 
4345 		/* If we're not ready, then normal ifup will take care
4346 		 * of this. Otherwise, we need to request our rs here.
4347 		 */
4348 		ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
4349 		update_rs = true;
4350 	}
4351 
4352 	write_lock_bh(&idev->lock);
4353 
4354 	if (update_rs)
4355 		idev->if_flags |= IF_RS_SENT;
4356 
4357 	/* Well, that's kinda nasty ... */
4358 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
4359 		spin_lock(&ifp->lock);
4360 		if (ifp->tokenized) {
4361 			ifp->valid_lft = 0;
4362 			ifp->prefered_lft = 0;
4363 		}
4364 		spin_unlock(&ifp->lock);
4365 	}
4366 
4367 	write_unlock_bh(&idev->lock);
4368 	return 0;
4369 }
4370 
4371 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla)
4372 {
4373 	int err = -EINVAL;
4374 	struct inet6_dev *idev = __in6_dev_get(dev);
4375 	struct nlattr *tb[IFLA_INET6_MAX + 1];
4376 
4377 	if (!idev)
4378 		return -EAFNOSUPPORT;
4379 
4380 	if (nla_parse_nested(tb, IFLA_INET6_MAX, nla, NULL) < 0)
4381 		BUG();
4382 
4383 	if (tb[IFLA_INET6_TOKEN])
4384 		err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]));
4385 
4386 	return err;
4387 }
4388 
4389 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
4390 			     u32 portid, u32 seq, int event, unsigned int flags)
4391 {
4392 	struct net_device *dev = idev->dev;
4393 	struct ifinfomsg *hdr;
4394 	struct nlmsghdr *nlh;
4395 	void *protoinfo;
4396 
4397 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
4398 	if (nlh == NULL)
4399 		return -EMSGSIZE;
4400 
4401 	hdr = nlmsg_data(nlh);
4402 	hdr->ifi_family = AF_INET6;
4403 	hdr->__ifi_pad = 0;
4404 	hdr->ifi_type = dev->type;
4405 	hdr->ifi_index = dev->ifindex;
4406 	hdr->ifi_flags = dev_get_flags(dev);
4407 	hdr->ifi_change = 0;
4408 
4409 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
4410 	    (dev->addr_len &&
4411 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
4412 	    nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
4413 	    (dev->ifindex != dev->iflink &&
4414 	     nla_put_u32(skb, IFLA_LINK, dev->iflink)))
4415 		goto nla_put_failure;
4416 	protoinfo = nla_nest_start(skb, IFLA_PROTINFO);
4417 	if (protoinfo == NULL)
4418 		goto nla_put_failure;
4419 
4420 	if (inet6_fill_ifla6_attrs(skb, idev) < 0)
4421 		goto nla_put_failure;
4422 
4423 	nla_nest_end(skb, protoinfo);
4424 	return nlmsg_end(skb, nlh);
4425 
4426 nla_put_failure:
4427 	nlmsg_cancel(skb, nlh);
4428 	return -EMSGSIZE;
4429 }
4430 
4431 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
4432 {
4433 	struct net *net = sock_net(skb->sk);
4434 	int h, s_h;
4435 	int idx = 0, s_idx;
4436 	struct net_device *dev;
4437 	struct inet6_dev *idev;
4438 	struct hlist_head *head;
4439 
4440 	s_h = cb->args[0];
4441 	s_idx = cb->args[1];
4442 
4443 	rcu_read_lock();
4444 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
4445 		idx = 0;
4446 		head = &net->dev_index_head[h];
4447 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
4448 			if (idx < s_idx)
4449 				goto cont;
4450 			idev = __in6_dev_get(dev);
4451 			if (!idev)
4452 				goto cont;
4453 			if (inet6_fill_ifinfo(skb, idev,
4454 					      NETLINK_CB(cb->skb).portid,
4455 					      cb->nlh->nlmsg_seq,
4456 					      RTM_NEWLINK, NLM_F_MULTI) <= 0)
4457 				goto out;
4458 cont:
4459 			idx++;
4460 		}
4461 	}
4462 out:
4463 	rcu_read_unlock();
4464 	cb->args[1] = idx;
4465 	cb->args[0] = h;
4466 
4467 	return skb->len;
4468 }
4469 
4470 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
4471 {
4472 	struct sk_buff *skb;
4473 	struct net *net = dev_net(idev->dev);
4474 	int err = -ENOBUFS;
4475 
4476 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
4477 	if (skb == NULL)
4478 		goto errout;
4479 
4480 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
4481 	if (err < 0) {
4482 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
4483 		WARN_ON(err == -EMSGSIZE);
4484 		kfree_skb(skb);
4485 		goto errout;
4486 	}
4487 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
4488 	return;
4489 errout:
4490 	if (err < 0)
4491 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
4492 }
4493 
4494 static inline size_t inet6_prefix_nlmsg_size(void)
4495 {
4496 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
4497 	       + nla_total_size(sizeof(struct in6_addr))
4498 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
4499 }
4500 
4501 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
4502 			     struct prefix_info *pinfo, u32 portid, u32 seq,
4503 			     int event, unsigned int flags)
4504 {
4505 	struct prefixmsg *pmsg;
4506 	struct nlmsghdr *nlh;
4507 	struct prefix_cacheinfo	ci;
4508 
4509 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
4510 	if (nlh == NULL)
4511 		return -EMSGSIZE;
4512 
4513 	pmsg = nlmsg_data(nlh);
4514 	pmsg->prefix_family = AF_INET6;
4515 	pmsg->prefix_pad1 = 0;
4516 	pmsg->prefix_pad2 = 0;
4517 	pmsg->prefix_ifindex = idev->dev->ifindex;
4518 	pmsg->prefix_len = pinfo->prefix_len;
4519 	pmsg->prefix_type = pinfo->type;
4520 	pmsg->prefix_pad3 = 0;
4521 	pmsg->prefix_flags = 0;
4522 	if (pinfo->onlink)
4523 		pmsg->prefix_flags |= IF_PREFIX_ONLINK;
4524 	if (pinfo->autoconf)
4525 		pmsg->prefix_flags |= IF_PREFIX_AUTOCONF;
4526 
4527 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
4528 		goto nla_put_failure;
4529 	ci.preferred_time = ntohl(pinfo->prefered);
4530 	ci.valid_time = ntohl(pinfo->valid);
4531 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
4532 		goto nla_put_failure;
4533 	return nlmsg_end(skb, nlh);
4534 
4535 nla_put_failure:
4536 	nlmsg_cancel(skb, nlh);
4537 	return -EMSGSIZE;
4538 }
4539 
4540 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
4541 			 struct prefix_info *pinfo)
4542 {
4543 	struct sk_buff *skb;
4544 	struct net *net = dev_net(idev->dev);
4545 	int err = -ENOBUFS;
4546 
4547 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
4548 	if (skb == NULL)
4549 		goto errout;
4550 
4551 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
4552 	if (err < 0) {
4553 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
4554 		WARN_ON(err == -EMSGSIZE);
4555 		kfree_skb(skb);
4556 		goto errout;
4557 	}
4558 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
4559 	return;
4560 errout:
4561 	if (err < 0)
4562 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
4563 }
4564 
4565 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
4566 {
4567 	struct net *net = dev_net(ifp->idev->dev);
4568 
4569 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
4570 
4571 	switch (event) {
4572 	case RTM_NEWADDR:
4573 		/*
4574 		 * If the address was optimistic
4575 		 * we inserted the route at the start of
4576 		 * our DAD process, so we don't need
4577 		 * to do it again
4578 		 */
4579 		if (!(ifp->rt->rt6i_node))
4580 			ip6_ins_rt(ifp->rt);
4581 		if (ifp->idev->cnf.forwarding)
4582 			addrconf_join_anycast(ifp);
4583 		if (!ipv6_addr_any(&ifp->peer_addr))
4584 			addrconf_prefix_route(&ifp->peer_addr, 128,
4585 					      ifp->idev->dev, 0, 0);
4586 		break;
4587 	case RTM_DELADDR:
4588 		if (ifp->idev->cnf.forwarding)
4589 			addrconf_leave_anycast(ifp);
4590 		addrconf_leave_solict(ifp->idev, &ifp->addr);
4591 		if (!ipv6_addr_any(&ifp->peer_addr)) {
4592 			struct rt6_info *rt;
4593 			struct net_device *dev = ifp->idev->dev;
4594 
4595 			rt = rt6_lookup(dev_net(dev), &ifp->peer_addr, NULL,
4596 					dev->ifindex, 1);
4597 			if (rt) {
4598 				dst_hold(&rt->dst);
4599 				if (ip6_del_rt(rt))
4600 					dst_free(&rt->dst);
4601 			}
4602 		}
4603 		dst_hold(&ifp->rt->dst);
4604 
4605 		if (ip6_del_rt(ifp->rt))
4606 			dst_free(&ifp->rt->dst);
4607 		break;
4608 	}
4609 	atomic_inc(&net->ipv6.dev_addr_genid);
4610 }
4611 
4612 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
4613 {
4614 	rcu_read_lock_bh();
4615 	if (likely(ifp->idev->dead == 0))
4616 		__ipv6_ifa_notify(event, ifp);
4617 	rcu_read_unlock_bh();
4618 }
4619 
4620 #ifdef CONFIG_SYSCTL
4621 
4622 static
4623 int addrconf_sysctl_forward(struct ctl_table *ctl, int write,
4624 			   void __user *buffer, size_t *lenp, loff_t *ppos)
4625 {
4626 	int *valp = ctl->data;
4627 	int val = *valp;
4628 	loff_t pos = *ppos;
4629 	struct ctl_table lctl;
4630 	int ret;
4631 
4632 	/*
4633 	 * ctl->data points to idev->cnf.forwarding, we should
4634 	 * not modify it until we get the rtnl lock.
4635 	 */
4636 	lctl = *ctl;
4637 	lctl.data = &val;
4638 
4639 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
4640 
4641 	if (write)
4642 		ret = addrconf_fixup_forwarding(ctl, valp, val);
4643 	if (ret)
4644 		*ppos = pos;
4645 	return ret;
4646 }
4647 
4648 static void dev_disable_change(struct inet6_dev *idev)
4649 {
4650 	struct netdev_notifier_info info;
4651 
4652 	if (!idev || !idev->dev)
4653 		return;
4654 
4655 	netdev_notifier_info_init(&info, idev->dev);
4656 	if (idev->cnf.disable_ipv6)
4657 		addrconf_notify(NULL, NETDEV_DOWN, &info);
4658 	else
4659 		addrconf_notify(NULL, NETDEV_UP, &info);
4660 }
4661 
4662 static void addrconf_disable_change(struct net *net, __s32 newf)
4663 {
4664 	struct net_device *dev;
4665 	struct inet6_dev *idev;
4666 
4667 	rcu_read_lock();
4668 	for_each_netdev_rcu(net, dev) {
4669 		idev = __in6_dev_get(dev);
4670 		if (idev) {
4671 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
4672 			idev->cnf.disable_ipv6 = newf;
4673 			if (changed)
4674 				dev_disable_change(idev);
4675 		}
4676 	}
4677 	rcu_read_unlock();
4678 }
4679 
4680 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
4681 {
4682 	struct net *net;
4683 	int old;
4684 
4685 	if (!rtnl_trylock())
4686 		return restart_syscall();
4687 
4688 	net = (struct net *)table->extra2;
4689 	old = *p;
4690 	*p = newf;
4691 
4692 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
4693 		rtnl_unlock();
4694 		return 0;
4695 	}
4696 
4697 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
4698 		net->ipv6.devconf_dflt->disable_ipv6 = newf;
4699 		addrconf_disable_change(net, newf);
4700 	} else if ((!newf) ^ (!old))
4701 		dev_disable_change((struct inet6_dev *)table->extra1);
4702 
4703 	rtnl_unlock();
4704 	return 0;
4705 }
4706 
4707 static
4708 int addrconf_sysctl_disable(struct ctl_table *ctl, int write,
4709 			    void __user *buffer, size_t *lenp, loff_t *ppos)
4710 {
4711 	int *valp = ctl->data;
4712 	int val = *valp;
4713 	loff_t pos = *ppos;
4714 	struct ctl_table lctl;
4715 	int ret;
4716 
4717 	/*
4718 	 * ctl->data points to idev->cnf.disable_ipv6, we should
4719 	 * not modify it until we get the rtnl lock.
4720 	 */
4721 	lctl = *ctl;
4722 	lctl.data = &val;
4723 
4724 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
4725 
4726 	if (write)
4727 		ret = addrconf_disable_ipv6(ctl, valp, val);
4728 	if (ret)
4729 		*ppos = pos;
4730 	return ret;
4731 }
4732 
4733 static struct addrconf_sysctl_table
4734 {
4735 	struct ctl_table_header *sysctl_header;
4736 	struct ctl_table addrconf_vars[DEVCONF_MAX+1];
4737 } addrconf_sysctl __read_mostly = {
4738 	.sysctl_header = NULL,
4739 	.addrconf_vars = {
4740 		{
4741 			.procname	= "forwarding",
4742 			.data		= &ipv6_devconf.forwarding,
4743 			.maxlen		= sizeof(int),
4744 			.mode		= 0644,
4745 			.proc_handler	= addrconf_sysctl_forward,
4746 		},
4747 		{
4748 			.procname	= "hop_limit",
4749 			.data		= &ipv6_devconf.hop_limit,
4750 			.maxlen		= sizeof(int),
4751 			.mode		= 0644,
4752 			.proc_handler	= proc_dointvec,
4753 		},
4754 		{
4755 			.procname	= "mtu",
4756 			.data		= &ipv6_devconf.mtu6,
4757 			.maxlen		= sizeof(int),
4758 			.mode		= 0644,
4759 			.proc_handler	= proc_dointvec,
4760 		},
4761 		{
4762 			.procname	= "accept_ra",
4763 			.data		= &ipv6_devconf.accept_ra,
4764 			.maxlen		= sizeof(int),
4765 			.mode		= 0644,
4766 			.proc_handler	= proc_dointvec,
4767 		},
4768 		{
4769 			.procname	= "accept_redirects",
4770 			.data		= &ipv6_devconf.accept_redirects,
4771 			.maxlen		= sizeof(int),
4772 			.mode		= 0644,
4773 			.proc_handler	= proc_dointvec,
4774 		},
4775 		{
4776 			.procname	= "autoconf",
4777 			.data		= &ipv6_devconf.autoconf,
4778 			.maxlen		= sizeof(int),
4779 			.mode		= 0644,
4780 			.proc_handler	= proc_dointvec,
4781 		},
4782 		{
4783 			.procname	= "dad_transmits",
4784 			.data		= &ipv6_devconf.dad_transmits,
4785 			.maxlen		= sizeof(int),
4786 			.mode		= 0644,
4787 			.proc_handler	= proc_dointvec,
4788 		},
4789 		{
4790 			.procname	= "router_solicitations",
4791 			.data		= &ipv6_devconf.rtr_solicits,
4792 			.maxlen		= sizeof(int),
4793 			.mode		= 0644,
4794 			.proc_handler	= proc_dointvec,
4795 		},
4796 		{
4797 			.procname	= "router_solicitation_interval",
4798 			.data		= &ipv6_devconf.rtr_solicit_interval,
4799 			.maxlen		= sizeof(int),
4800 			.mode		= 0644,
4801 			.proc_handler	= proc_dointvec_jiffies,
4802 		},
4803 		{
4804 			.procname	= "router_solicitation_delay",
4805 			.data		= &ipv6_devconf.rtr_solicit_delay,
4806 			.maxlen		= sizeof(int),
4807 			.mode		= 0644,
4808 			.proc_handler	= proc_dointvec_jiffies,
4809 		},
4810 		{
4811 			.procname	= "force_mld_version",
4812 			.data		= &ipv6_devconf.force_mld_version,
4813 			.maxlen		= sizeof(int),
4814 			.mode		= 0644,
4815 			.proc_handler	= proc_dointvec,
4816 		},
4817 #ifdef CONFIG_IPV6_PRIVACY
4818 		{
4819 			.procname	= "use_tempaddr",
4820 			.data		= &ipv6_devconf.use_tempaddr,
4821 			.maxlen		= sizeof(int),
4822 			.mode		= 0644,
4823 			.proc_handler	= proc_dointvec,
4824 		},
4825 		{
4826 			.procname	= "temp_valid_lft",
4827 			.data		= &ipv6_devconf.temp_valid_lft,
4828 			.maxlen		= sizeof(int),
4829 			.mode		= 0644,
4830 			.proc_handler	= proc_dointvec,
4831 		},
4832 		{
4833 			.procname	= "temp_prefered_lft",
4834 			.data		= &ipv6_devconf.temp_prefered_lft,
4835 			.maxlen		= sizeof(int),
4836 			.mode		= 0644,
4837 			.proc_handler	= proc_dointvec,
4838 		},
4839 		{
4840 			.procname	= "regen_max_retry",
4841 			.data		= &ipv6_devconf.regen_max_retry,
4842 			.maxlen		= sizeof(int),
4843 			.mode		= 0644,
4844 			.proc_handler	= proc_dointvec,
4845 		},
4846 		{
4847 			.procname	= "max_desync_factor",
4848 			.data		= &ipv6_devconf.max_desync_factor,
4849 			.maxlen		= sizeof(int),
4850 			.mode		= 0644,
4851 			.proc_handler	= proc_dointvec,
4852 		},
4853 #endif
4854 		{
4855 			.procname	= "max_addresses",
4856 			.data		= &ipv6_devconf.max_addresses,
4857 			.maxlen		= sizeof(int),
4858 			.mode		= 0644,
4859 			.proc_handler	= proc_dointvec,
4860 		},
4861 		{
4862 			.procname	= "accept_ra_defrtr",
4863 			.data		= &ipv6_devconf.accept_ra_defrtr,
4864 			.maxlen		= sizeof(int),
4865 			.mode		= 0644,
4866 			.proc_handler	= proc_dointvec,
4867 		},
4868 		{
4869 			.procname	= "accept_ra_pinfo",
4870 			.data		= &ipv6_devconf.accept_ra_pinfo,
4871 			.maxlen		= sizeof(int),
4872 			.mode		= 0644,
4873 			.proc_handler	= proc_dointvec,
4874 		},
4875 #ifdef CONFIG_IPV6_ROUTER_PREF
4876 		{
4877 			.procname	= "accept_ra_rtr_pref",
4878 			.data		= &ipv6_devconf.accept_ra_rtr_pref,
4879 			.maxlen		= sizeof(int),
4880 			.mode		= 0644,
4881 			.proc_handler	= proc_dointvec,
4882 		},
4883 		{
4884 			.procname	= "router_probe_interval",
4885 			.data		= &ipv6_devconf.rtr_probe_interval,
4886 			.maxlen		= sizeof(int),
4887 			.mode		= 0644,
4888 			.proc_handler	= proc_dointvec_jiffies,
4889 		},
4890 #ifdef CONFIG_IPV6_ROUTE_INFO
4891 		{
4892 			.procname	= "accept_ra_rt_info_max_plen",
4893 			.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
4894 			.maxlen		= sizeof(int),
4895 			.mode		= 0644,
4896 			.proc_handler	= proc_dointvec,
4897 		},
4898 #endif
4899 #endif
4900 		{
4901 			.procname	= "proxy_ndp",
4902 			.data		= &ipv6_devconf.proxy_ndp,
4903 			.maxlen		= sizeof(int),
4904 			.mode		= 0644,
4905 			.proc_handler	= proc_dointvec,
4906 		},
4907 		{
4908 			.procname	= "accept_source_route",
4909 			.data		= &ipv6_devconf.accept_source_route,
4910 			.maxlen		= sizeof(int),
4911 			.mode		= 0644,
4912 			.proc_handler	= proc_dointvec,
4913 		},
4914 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
4915 		{
4916 			.procname       = "optimistic_dad",
4917 			.data           = &ipv6_devconf.optimistic_dad,
4918 			.maxlen         = sizeof(int),
4919 			.mode           = 0644,
4920 			.proc_handler   = proc_dointvec,
4921 
4922 		},
4923 #endif
4924 #ifdef CONFIG_IPV6_MROUTE
4925 		{
4926 			.procname	= "mc_forwarding",
4927 			.data		= &ipv6_devconf.mc_forwarding,
4928 			.maxlen		= sizeof(int),
4929 			.mode		= 0444,
4930 			.proc_handler	= proc_dointvec,
4931 		},
4932 #endif
4933 		{
4934 			.procname	= "disable_ipv6",
4935 			.data		= &ipv6_devconf.disable_ipv6,
4936 			.maxlen		= sizeof(int),
4937 			.mode		= 0644,
4938 			.proc_handler	= addrconf_sysctl_disable,
4939 		},
4940 		{
4941 			.procname	= "accept_dad",
4942 			.data		= &ipv6_devconf.accept_dad,
4943 			.maxlen		= sizeof(int),
4944 			.mode		= 0644,
4945 			.proc_handler	= proc_dointvec,
4946 		},
4947 		{
4948 			.procname       = "force_tllao",
4949 			.data           = &ipv6_devconf.force_tllao,
4950 			.maxlen         = sizeof(int),
4951 			.mode           = 0644,
4952 			.proc_handler   = proc_dointvec
4953 		},
4954 		{
4955 			.procname       = "ndisc_notify",
4956 			.data           = &ipv6_devconf.ndisc_notify,
4957 			.maxlen         = sizeof(int),
4958 			.mode           = 0644,
4959 			.proc_handler   = proc_dointvec
4960 		},
4961 		{
4962 			/* sentinel */
4963 		}
4964 	},
4965 };
4966 
4967 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
4968 		struct inet6_dev *idev, struct ipv6_devconf *p)
4969 {
4970 	int i;
4971 	struct addrconf_sysctl_table *t;
4972 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
4973 
4974 	t = kmemdup(&addrconf_sysctl, sizeof(*t), GFP_KERNEL);
4975 	if (t == NULL)
4976 		goto out;
4977 
4978 	for (i = 0; t->addrconf_vars[i].data; i++) {
4979 		t->addrconf_vars[i].data += (char *)p - (char *)&ipv6_devconf;
4980 		t->addrconf_vars[i].extra1 = idev; /* embedded; no ref */
4981 		t->addrconf_vars[i].extra2 = net;
4982 	}
4983 
4984 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
4985 
4986 	t->sysctl_header = register_net_sysctl(net, path, t->addrconf_vars);
4987 	if (t->sysctl_header == NULL)
4988 		goto free;
4989 
4990 	p->sysctl = t;
4991 	return 0;
4992 
4993 free:
4994 	kfree(t);
4995 out:
4996 	return -ENOBUFS;
4997 }
4998 
4999 static void __addrconf_sysctl_unregister(struct ipv6_devconf *p)
5000 {
5001 	struct addrconf_sysctl_table *t;
5002 
5003 	if (p->sysctl == NULL)
5004 		return;
5005 
5006 	t = p->sysctl;
5007 	p->sysctl = NULL;
5008 	unregister_net_sysctl_table(t->sysctl_header);
5009 	kfree(t);
5010 }
5011 
5012 static void addrconf_sysctl_register(struct inet6_dev *idev)
5013 {
5014 	neigh_sysctl_register(idev->dev, idev->nd_parms, "ipv6",
5015 			      &ndisc_ifinfo_sysctl_change);
5016 	__addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
5017 					idev, &idev->cnf);
5018 }
5019 
5020 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
5021 {
5022 	__addrconf_sysctl_unregister(&idev->cnf);
5023 	neigh_sysctl_unregister(idev->nd_parms);
5024 }
5025 
5026 
5027 #endif
5028 
5029 static int __net_init addrconf_init_net(struct net *net)
5030 {
5031 	int err = -ENOMEM;
5032 	struct ipv6_devconf *all, *dflt;
5033 
5034 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
5035 	if (all == NULL)
5036 		goto err_alloc_all;
5037 
5038 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
5039 	if (dflt == NULL)
5040 		goto err_alloc_dflt;
5041 
5042 	/* these will be inherited by all namespaces */
5043 	dflt->autoconf = ipv6_defaults.autoconf;
5044 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
5045 
5046 	net->ipv6.devconf_all = all;
5047 	net->ipv6.devconf_dflt = dflt;
5048 
5049 #ifdef CONFIG_SYSCTL
5050 	err = __addrconf_sysctl_register(net, "all", NULL, all);
5051 	if (err < 0)
5052 		goto err_reg_all;
5053 
5054 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
5055 	if (err < 0)
5056 		goto err_reg_dflt;
5057 #endif
5058 	return 0;
5059 
5060 #ifdef CONFIG_SYSCTL
5061 err_reg_dflt:
5062 	__addrconf_sysctl_unregister(all);
5063 err_reg_all:
5064 	kfree(dflt);
5065 #endif
5066 err_alloc_dflt:
5067 	kfree(all);
5068 err_alloc_all:
5069 	return err;
5070 }
5071 
5072 static void __net_exit addrconf_exit_net(struct net *net)
5073 {
5074 #ifdef CONFIG_SYSCTL
5075 	__addrconf_sysctl_unregister(net->ipv6.devconf_dflt);
5076 	__addrconf_sysctl_unregister(net->ipv6.devconf_all);
5077 #endif
5078 	if (!net_eq(net, &init_net)) {
5079 		kfree(net->ipv6.devconf_dflt);
5080 		kfree(net->ipv6.devconf_all);
5081 	}
5082 }
5083 
5084 static struct pernet_operations addrconf_ops = {
5085 	.init = addrconf_init_net,
5086 	.exit = addrconf_exit_net,
5087 };
5088 
5089 static struct rtnl_af_ops inet6_ops = {
5090 	.family		  = AF_INET6,
5091 	.fill_link_af	  = inet6_fill_link_af,
5092 	.get_link_af_size = inet6_get_link_af_size,
5093 	.set_link_af	  = inet6_set_link_af,
5094 };
5095 
5096 /*
5097  *	Init / cleanup code
5098  */
5099 
5100 int __init addrconf_init(void)
5101 {
5102 	int i, err;
5103 
5104 	err = ipv6_addr_label_init();
5105 	if (err < 0) {
5106 		pr_crit("%s: cannot initialize default policy table: %d\n",
5107 			__func__, err);
5108 		goto out;
5109 	}
5110 
5111 	err = register_pernet_subsys(&addrconf_ops);
5112 	if (err < 0)
5113 		goto out_addrlabel;
5114 
5115 	/* The addrconf netdev notifier requires that loopback_dev
5116 	 * has it's ipv6 private information allocated and setup
5117 	 * before it can bring up and give link-local addresses
5118 	 * to other devices which are up.
5119 	 *
5120 	 * Unfortunately, loopback_dev is not necessarily the first
5121 	 * entry in the global dev_base list of net devices.  In fact,
5122 	 * it is likely to be the very last entry on that list.
5123 	 * So this causes the notifier registry below to try and
5124 	 * give link-local addresses to all devices besides loopback_dev
5125 	 * first, then loopback_dev, which cases all the non-loopback_dev
5126 	 * devices to fail to get a link-local address.
5127 	 *
5128 	 * So, as a temporary fix, allocate the ipv6 structure for
5129 	 * loopback_dev first by hand.
5130 	 * Longer term, all of the dependencies ipv6 has upon the loopback
5131 	 * device and it being up should be removed.
5132 	 */
5133 	rtnl_lock();
5134 	if (!ipv6_add_dev(init_net.loopback_dev))
5135 		err = -ENOMEM;
5136 	rtnl_unlock();
5137 	if (err)
5138 		goto errlo;
5139 
5140 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
5141 		INIT_HLIST_HEAD(&inet6_addr_lst[i]);
5142 
5143 	register_netdevice_notifier(&ipv6_dev_notf);
5144 
5145 	addrconf_verify(0);
5146 
5147 	err = rtnl_af_register(&inet6_ops);
5148 	if (err < 0)
5149 		goto errout_af;
5150 
5151 	err = __rtnl_register(PF_INET6, RTM_GETLINK, NULL, inet6_dump_ifinfo,
5152 			      NULL);
5153 	if (err < 0)
5154 		goto errout;
5155 
5156 	/* Only the first call to __rtnl_register can fail */
5157 	__rtnl_register(PF_INET6, RTM_NEWADDR, inet6_rtm_newaddr, NULL, NULL);
5158 	__rtnl_register(PF_INET6, RTM_DELADDR, inet6_rtm_deladdr, NULL, NULL);
5159 	__rtnl_register(PF_INET6, RTM_GETADDR, inet6_rtm_getaddr,
5160 			inet6_dump_ifaddr, NULL);
5161 	__rtnl_register(PF_INET6, RTM_GETMULTICAST, NULL,
5162 			inet6_dump_ifmcaddr, NULL);
5163 	__rtnl_register(PF_INET6, RTM_GETANYCAST, NULL,
5164 			inet6_dump_ifacaddr, NULL);
5165 	__rtnl_register(PF_INET6, RTM_GETNETCONF, inet6_netconf_get_devconf,
5166 			inet6_netconf_dump_devconf, NULL);
5167 
5168 	ipv6_addr_label_rtnl_register();
5169 
5170 	return 0;
5171 errout:
5172 	rtnl_af_unregister(&inet6_ops);
5173 errout_af:
5174 	unregister_netdevice_notifier(&ipv6_dev_notf);
5175 errlo:
5176 	unregister_pernet_subsys(&addrconf_ops);
5177 out_addrlabel:
5178 	ipv6_addr_label_cleanup();
5179 out:
5180 	return err;
5181 }
5182 
5183 void addrconf_cleanup(void)
5184 {
5185 	struct net_device *dev;
5186 	int i;
5187 
5188 	unregister_netdevice_notifier(&ipv6_dev_notf);
5189 	unregister_pernet_subsys(&addrconf_ops);
5190 	ipv6_addr_label_cleanup();
5191 
5192 	rtnl_lock();
5193 
5194 	__rtnl_af_unregister(&inet6_ops);
5195 
5196 	/* clean dev list */
5197 	for_each_netdev(&init_net, dev) {
5198 		if (__in6_dev_get(dev) == NULL)
5199 			continue;
5200 		addrconf_ifdown(dev, 1);
5201 	}
5202 	addrconf_ifdown(init_net.loopback_dev, 2);
5203 
5204 	/*
5205 	 *	Check hash table.
5206 	 */
5207 	spin_lock_bh(&addrconf_hash_lock);
5208 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
5209 		WARN_ON(!hlist_empty(&inet6_addr_lst[i]));
5210 	spin_unlock_bh(&addrconf_hash_lock);
5211 
5212 	del_timer(&addr_chk_timer);
5213 	rtnl_unlock();
5214 }
5215