ipv6: Revert 'administrative down' address handling changes.
[pandora-kernel.git] / net / ipv6 / addrconf.c
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 #include <linux/errno.h>
42 #include <linux/types.h>
43 #include <linux/kernel.h>
44 #include <linux/socket.h>
45 #include <linux/sockios.h>
46 #include <linux/net.h>
47 #include <linux/in6.h>
48 #include <linux/netdevice.h>
49 #include <linux/if_addr.h>
50 #include <linux/if_arp.h>
51 #include <linux/if_arcnet.h>
52 #include <linux/if_infiniband.h>
53 #include <linux/route.h>
54 #include <linux/inetdevice.h>
55 #include <linux/init.h>
56 #include <linux/slab.h>
57 #ifdef CONFIG_SYSCTL
58 #include <linux/sysctl.h>
59 #endif
60 #include <linux/capability.h>
61 #include <linux/delay.h>
62 #include <linux/notifier.h>
63 #include <linux/string.h>
64
65 #include <net/net_namespace.h>
66 #include <net/sock.h>
67 #include <net/snmp.h>
68
69 #include <net/ipv6.h>
70 #include <net/protocol.h>
71 #include <net/ndisc.h>
72 #include <net/ip6_route.h>
73 #include <net/addrconf.h>
74 #include <net/tcp.h>
75 #include <net/ip.h>
76 #include <net/netlink.h>
77 #include <net/pkt_sched.h>
78 #include <linux/if_tunnel.h>
79 #include <linux/rtnetlink.h>
80
81 #ifdef CONFIG_IPV6_PRIVACY
82 #include <linux/random.h>
83 #endif
84
85 #include <linux/uaccess.h>
86 #include <asm/unaligned.h>
87
88 #include <linux/proc_fs.h>
89 #include <linux/seq_file.h>
90
91 /* Set to 3 to get tracing... */
92 #define ACONF_DEBUG 2
93
94 #if ACONF_DEBUG >= 3
95 #define ADBG(x) printk x
96 #else
97 #define ADBG(x)
98 #endif
99
100 #define INFINITY_LIFE_TIME      0xFFFFFFFF
101
102 static inline u32 cstamp_delta(unsigned long cstamp)
103 {
104         return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
105 }
106
107 #define ADDRCONF_TIMER_FUZZ_MINUS       (HZ > 50 ? HZ/50 : 1)
108 #define ADDRCONF_TIMER_FUZZ             (HZ / 4)
109 #define ADDRCONF_TIMER_FUZZ_MAX         (HZ)
110
111 #ifdef CONFIG_SYSCTL
112 static void addrconf_sysctl_register(struct inet6_dev *idev);
113 static void addrconf_sysctl_unregister(struct inet6_dev *idev);
114 #else
115 static inline void addrconf_sysctl_register(struct inet6_dev *idev)
116 {
117 }
118
119 static inline void addrconf_sysctl_unregister(struct inet6_dev *idev)
120 {
121 }
122 #endif
123
124 #ifdef CONFIG_IPV6_PRIVACY
125 static int __ipv6_regen_rndid(struct inet6_dev *idev);
126 static int __ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr);
127 static void ipv6_regen_rndid(unsigned long data);
128 #endif
129
130 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev);
131 static int ipv6_count_addresses(struct inet6_dev *idev);
132
133 /*
134  *      Configured unicast address hash table
135  */
136 static struct hlist_head inet6_addr_lst[IN6_ADDR_HSIZE];
137 static DEFINE_SPINLOCK(addrconf_hash_lock);
138
139 static void addrconf_verify(unsigned long);
140
141 static DEFINE_TIMER(addr_chk_timer, addrconf_verify, 0, 0);
142 static DEFINE_SPINLOCK(addrconf_verify_lock);
143
144 static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
145 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
146
147 static void addrconf_type_change(struct net_device *dev,
148                                  unsigned long event);
149 static int addrconf_ifdown(struct net_device *dev, int how);
150
151 static void addrconf_dad_start(struct inet6_ifaddr *ifp, u32 flags);
152 static void addrconf_dad_timer(unsigned long data);
153 static void addrconf_dad_completed(struct inet6_ifaddr *ifp);
154 static void addrconf_dad_run(struct inet6_dev *idev);
155 static void addrconf_rs_timer(unsigned long data);
156 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
157 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
158
159 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
160                                 struct prefix_info *pinfo);
161 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
162                                struct net_device *dev);
163
164 static ATOMIC_NOTIFIER_HEAD(inet6addr_chain);
165
166 static struct ipv6_devconf ipv6_devconf __read_mostly = {
167         .forwarding             = 0,
168         .hop_limit              = IPV6_DEFAULT_HOPLIMIT,
169         .mtu6                   = IPV6_MIN_MTU,
170         .accept_ra              = 1,
171         .accept_redirects       = 1,
172         .autoconf               = 1,
173         .force_mld_version      = 0,
174         .dad_transmits          = 1,
175         .rtr_solicits           = MAX_RTR_SOLICITATIONS,
176         .rtr_solicit_interval   = RTR_SOLICITATION_INTERVAL,
177         .rtr_solicit_delay      = MAX_RTR_SOLICITATION_DELAY,
178 #ifdef CONFIG_IPV6_PRIVACY
179         .use_tempaddr           = 0,
180         .temp_valid_lft         = TEMP_VALID_LIFETIME,
181         .temp_prefered_lft      = TEMP_PREFERRED_LIFETIME,
182         .regen_max_retry        = REGEN_MAX_RETRY,
183         .max_desync_factor      = MAX_DESYNC_FACTOR,
184 #endif
185         .max_addresses          = IPV6_MAX_ADDRESSES,
186         .accept_ra_defrtr       = 1,
187         .accept_ra_pinfo        = 1,
188 #ifdef CONFIG_IPV6_ROUTER_PREF
189         .accept_ra_rtr_pref     = 1,
190         .rtr_probe_interval     = 60 * HZ,
191 #ifdef CONFIG_IPV6_ROUTE_INFO
192         .accept_ra_rt_info_max_plen = 0,
193 #endif
194 #endif
195         .proxy_ndp              = 0,
196         .accept_source_route    = 0,    /* we do not accept RH0 by default. */
197         .disable_ipv6           = 0,
198         .accept_dad             = 1,
199 };
200
201 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
202         .forwarding             = 0,
203         .hop_limit              = IPV6_DEFAULT_HOPLIMIT,
204         .mtu6                   = IPV6_MIN_MTU,
205         .accept_ra              = 1,
206         .accept_redirects       = 1,
207         .autoconf               = 1,
208         .dad_transmits          = 1,
209         .rtr_solicits           = MAX_RTR_SOLICITATIONS,
210         .rtr_solicit_interval   = RTR_SOLICITATION_INTERVAL,
211         .rtr_solicit_delay      = MAX_RTR_SOLICITATION_DELAY,
212 #ifdef CONFIG_IPV6_PRIVACY
213         .use_tempaddr           = 0,
214         .temp_valid_lft         = TEMP_VALID_LIFETIME,
215         .temp_prefered_lft      = TEMP_PREFERRED_LIFETIME,
216         .regen_max_retry        = REGEN_MAX_RETRY,
217         .max_desync_factor      = MAX_DESYNC_FACTOR,
218 #endif
219         .max_addresses          = IPV6_MAX_ADDRESSES,
220         .accept_ra_defrtr       = 1,
221         .accept_ra_pinfo        = 1,
222 #ifdef CONFIG_IPV6_ROUTER_PREF
223         .accept_ra_rtr_pref     = 1,
224         .rtr_probe_interval     = 60 * HZ,
225 #ifdef CONFIG_IPV6_ROUTE_INFO
226         .accept_ra_rt_info_max_plen = 0,
227 #endif
228 #endif
229         .proxy_ndp              = 0,
230         .accept_source_route    = 0,    /* we do not accept RH0 by default. */
231         .disable_ipv6           = 0,
232         .accept_dad             = 1,
233 };
234
235 /* IPv6 Wildcard Address and Loopback Address defined by RFC2553 */
236 const struct in6_addr in6addr_any = IN6ADDR_ANY_INIT;
237 const struct in6_addr in6addr_loopback = IN6ADDR_LOOPBACK_INIT;
238 const struct in6_addr in6addr_linklocal_allnodes = IN6ADDR_LINKLOCAL_ALLNODES_INIT;
239 const struct in6_addr in6addr_linklocal_allrouters = IN6ADDR_LINKLOCAL_ALLROUTERS_INIT;
240
241 /* Check if a valid qdisc is available */
242 static inline bool addrconf_qdisc_ok(const struct net_device *dev)
243 {
244         return !qdisc_tx_is_noop(dev);
245 }
246
247 /* Check if a route is valid prefix route */
248 static inline int addrconf_is_prefix_route(const struct rt6_info *rt)
249 {
250         return (rt->rt6i_flags & (RTF_GATEWAY | RTF_DEFAULT)) == 0;
251 }
252
253 static void addrconf_del_timer(struct inet6_ifaddr *ifp)
254 {
255         if (del_timer(&ifp->timer))
256                 __in6_ifa_put(ifp);
257 }
258
259 enum addrconf_timer_t {
260         AC_NONE,
261         AC_DAD,
262         AC_RS,
263 };
264
265 static void addrconf_mod_timer(struct inet6_ifaddr *ifp,
266                                enum addrconf_timer_t what,
267                                unsigned long when)
268 {
269         if (!del_timer(&ifp->timer))
270                 in6_ifa_hold(ifp);
271
272         switch (what) {
273         case AC_DAD:
274                 ifp->timer.function = addrconf_dad_timer;
275                 break;
276         case AC_RS:
277                 ifp->timer.function = addrconf_rs_timer;
278                 break;
279         default:
280                 break;
281         }
282         ifp->timer.expires = jiffies + when;
283         add_timer(&ifp->timer);
284 }
285
286 static int snmp6_alloc_dev(struct inet6_dev *idev)
287 {
288         if (snmp_mib_init((void __percpu **)idev->stats.ipv6,
289                           sizeof(struct ipstats_mib),
290                           __alignof__(struct ipstats_mib)) < 0)
291                 goto err_ip;
292         if (snmp_mib_init((void __percpu **)idev->stats.icmpv6,
293                           sizeof(struct icmpv6_mib),
294                           __alignof__(struct icmpv6_mib)) < 0)
295                 goto err_icmp;
296         if (snmp_mib_init((void __percpu **)idev->stats.icmpv6msg,
297                           sizeof(struct icmpv6msg_mib),
298                           __alignof__(struct icmpv6msg_mib)) < 0)
299                 goto err_icmpmsg;
300
301         return 0;
302
303 err_icmpmsg:
304         snmp_mib_free((void __percpu **)idev->stats.icmpv6);
305 err_icmp:
306         snmp_mib_free((void __percpu **)idev->stats.ipv6);
307 err_ip:
308         return -ENOMEM;
309 }
310
311 static void snmp6_free_dev(struct inet6_dev *idev)
312 {
313         snmp_mib_free((void __percpu **)idev->stats.icmpv6msg);
314         snmp_mib_free((void __percpu **)idev->stats.icmpv6);
315         snmp_mib_free((void __percpu **)idev->stats.ipv6);
316 }
317
318 /* Nobody refers to this device, we may destroy it. */
319
320 static void in6_dev_finish_destroy_rcu(struct rcu_head *head)
321 {
322         struct inet6_dev *idev = container_of(head, struct inet6_dev, rcu);
323         kfree(idev);
324 }
325
326 void in6_dev_finish_destroy(struct inet6_dev *idev)
327 {
328         struct net_device *dev = idev->dev;
329
330         WARN_ON(!list_empty(&idev->addr_list));
331         WARN_ON(idev->mc_list != NULL);
332
333 #ifdef NET_REFCNT_DEBUG
334         printk(KERN_DEBUG "in6_dev_finish_destroy: %s\n", dev ? dev->name : "NIL");
335 #endif
336         dev_put(dev);
337         if (!idev->dead) {
338                 pr_warning("Freeing alive inet6 device %p\n", idev);
339                 return;
340         }
341         snmp6_free_dev(idev);
342         call_rcu(&idev->rcu, in6_dev_finish_destroy_rcu);
343 }
344
345 EXPORT_SYMBOL(in6_dev_finish_destroy);
346
347 static struct inet6_dev * ipv6_add_dev(struct net_device *dev)
348 {
349         struct inet6_dev *ndev;
350
351         ASSERT_RTNL();
352
353         if (dev->mtu < IPV6_MIN_MTU)
354                 return NULL;
355
356         ndev = kzalloc(sizeof(struct inet6_dev), GFP_KERNEL);
357
358         if (ndev == NULL)
359                 return NULL;
360
361         rwlock_init(&ndev->lock);
362         ndev->dev = dev;
363         INIT_LIST_HEAD(&ndev->addr_list);
364
365         memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
366         ndev->cnf.mtu6 = dev->mtu;
367         ndev->cnf.sysctl = NULL;
368         ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
369         if (ndev->nd_parms == NULL) {
370                 kfree(ndev);
371                 return NULL;
372         }
373         if (ndev->cnf.forwarding)
374                 dev_disable_lro(dev);
375         /* We refer to the device */
376         dev_hold(dev);
377
378         if (snmp6_alloc_dev(ndev) < 0) {
379                 ADBG((KERN_WARNING
380                         "%s(): cannot allocate memory for statistics; dev=%s.\n",
381                         __func__, dev->name));
382                 neigh_parms_release(&nd_tbl, ndev->nd_parms);
383                 ndev->dead = 1;
384                 in6_dev_finish_destroy(ndev);
385                 return NULL;
386         }
387
388         if (snmp6_register_dev(ndev) < 0) {
389                 ADBG((KERN_WARNING
390                         "%s(): cannot create /proc/net/dev_snmp6/%s\n",
391                         __func__, dev->name));
392                 neigh_parms_release(&nd_tbl, ndev->nd_parms);
393                 ndev->dead = 1;
394                 in6_dev_finish_destroy(ndev);
395                 return NULL;
396         }
397
398         /* One reference from device.  We must do this before
399          * we invoke __ipv6_regen_rndid().
400          */
401         in6_dev_hold(ndev);
402
403         if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
404                 ndev->cnf.accept_dad = -1;
405
406 #if defined(CONFIG_IPV6_SIT) || defined(CONFIG_IPV6_SIT_MODULE)
407         if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
408                 printk(KERN_INFO
409                        "%s: Disabled Multicast RS\n",
410                        dev->name);
411                 ndev->cnf.rtr_solicits = 0;
412         }
413 #endif
414
415 #ifdef CONFIG_IPV6_PRIVACY
416         INIT_LIST_HEAD(&ndev->tempaddr_list);
417         setup_timer(&ndev->regen_timer, ipv6_regen_rndid, (unsigned long)ndev);
418         if ((dev->flags&IFF_LOOPBACK) ||
419             dev->type == ARPHRD_TUNNEL ||
420             dev->type == ARPHRD_TUNNEL6 ||
421             dev->type == ARPHRD_SIT ||
422             dev->type == ARPHRD_NONE) {
423                 ndev->cnf.use_tempaddr = -1;
424         } else {
425                 in6_dev_hold(ndev);
426                 ipv6_regen_rndid((unsigned long) ndev);
427         }
428 #endif
429
430         if (netif_running(dev) && addrconf_qdisc_ok(dev))
431                 ndev->if_flags |= IF_READY;
432
433         ipv6_mc_init_dev(ndev);
434         ndev->tstamp = jiffies;
435         addrconf_sysctl_register(ndev);
436         /* protected by rtnl_lock */
437         rcu_assign_pointer(dev->ip6_ptr, ndev);
438
439         /* Join all-node multicast group */
440         ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
441
442         return ndev;
443 }
444
445 static struct inet6_dev * ipv6_find_idev(struct net_device *dev)
446 {
447         struct inet6_dev *idev;
448
449         ASSERT_RTNL();
450
451         idev = __in6_dev_get(dev);
452         if (!idev) {
453                 idev = ipv6_add_dev(dev);
454                 if (!idev)
455                         return NULL;
456         }
457
458         if (dev->flags&IFF_UP)
459                 ipv6_mc_up(idev);
460         return idev;
461 }
462
463 #ifdef CONFIG_SYSCTL
464 static void dev_forward_change(struct inet6_dev *idev)
465 {
466         struct net_device *dev;
467         struct inet6_ifaddr *ifa;
468
469         if (!idev)
470                 return;
471         dev = idev->dev;
472         if (idev->cnf.forwarding)
473                 dev_disable_lro(dev);
474         if (dev && (dev->flags & IFF_MULTICAST)) {
475                 if (idev->cnf.forwarding)
476                         ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
477                 else
478                         ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
479         }
480
481         list_for_each_entry(ifa, &idev->addr_list, if_list) {
482                 if (ifa->flags&IFA_F_TENTATIVE)
483                         continue;
484                 if (idev->cnf.forwarding)
485                         addrconf_join_anycast(ifa);
486                 else
487                         addrconf_leave_anycast(ifa);
488         }
489 }
490
491
492 static void addrconf_forward_change(struct net *net, __s32 newf)
493 {
494         struct net_device *dev;
495         struct inet6_dev *idev;
496
497         rcu_read_lock();
498         for_each_netdev_rcu(net, dev) {
499                 idev = __in6_dev_get(dev);
500                 if (idev) {
501                         int changed = (!idev->cnf.forwarding) ^ (!newf);
502                         idev->cnf.forwarding = newf;
503                         if (changed)
504                                 dev_forward_change(idev);
505                 }
506         }
507         rcu_read_unlock();
508 }
509
510 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int old)
511 {
512         struct net *net;
513
514         net = (struct net *)table->extra2;
515         if (p == &net->ipv6.devconf_dflt->forwarding)
516                 return 0;
517
518         if (!rtnl_trylock()) {
519                 /* Restore the original values before restarting */
520                 *p = old;
521                 return restart_syscall();
522         }
523
524         if (p == &net->ipv6.devconf_all->forwarding) {
525                 __s32 newf = net->ipv6.devconf_all->forwarding;
526                 net->ipv6.devconf_dflt->forwarding = newf;
527                 addrconf_forward_change(net, newf);
528         } else if ((!*p) ^ (!old))
529                 dev_forward_change((struct inet6_dev *)table->extra1);
530         rtnl_unlock();
531
532         if (*p)
533                 rt6_purge_dflt_routers(net);
534         return 1;
535 }
536 #endif
537
538 static void inet6_ifa_finish_destroy_rcu(struct rcu_head *head)
539 {
540         struct inet6_ifaddr *ifp = container_of(head, struct inet6_ifaddr, rcu);
541         kfree(ifp);
542 }
543
544 /* Nobody refers to this ifaddr, destroy it */
545 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
546 {
547         WARN_ON(!hlist_unhashed(&ifp->addr_lst));
548
549 #ifdef NET_REFCNT_DEBUG
550         printk(KERN_DEBUG "inet6_ifa_finish_destroy\n");
551 #endif
552
553         in6_dev_put(ifp->idev);
554
555         if (del_timer(&ifp->timer))
556                 pr_notice("Timer is still running, when freeing ifa=%p\n", ifp);
557
558         if (ifp->state != INET6_IFADDR_STATE_DEAD) {
559                 pr_warning("Freeing alive inet6 address %p\n", ifp);
560                 return;
561         }
562         dst_release(&ifp->rt->dst);
563
564         call_rcu(&ifp->rcu, inet6_ifa_finish_destroy_rcu);
565 }
566
567 static void
568 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
569 {
570         struct list_head *p;
571         int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
572
573         /*
574          * Each device address list is sorted in order of scope -
575          * global before linklocal.
576          */
577         list_for_each(p, &idev->addr_list) {
578                 struct inet6_ifaddr *ifa
579                         = list_entry(p, struct inet6_ifaddr, if_list);
580                 if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
581                         break;
582         }
583
584         list_add_tail(&ifp->if_list, p);
585 }
586
587 static u32 ipv6_addr_hash(const struct in6_addr *addr)
588 {
589         /*
590          * We perform the hash function over the last 64 bits of the address
591          * This will include the IEEE address token on links that support it.
592          */
593         return jhash_2words((__force u32)addr->s6_addr32[2],
594                             (__force u32)addr->s6_addr32[3], 0)
595                 & (IN6_ADDR_HSIZE - 1);
596 }
597
598 /* On success it returns ifp with increased reference count */
599
600 static struct inet6_ifaddr *
601 ipv6_add_addr(struct inet6_dev *idev, const struct in6_addr *addr, int pfxlen,
602               int scope, u32 flags)
603 {
604         struct inet6_ifaddr *ifa = NULL;
605         struct rt6_info *rt;
606         unsigned int hash;
607         int err = 0;
608         int addr_type = ipv6_addr_type(addr);
609
610         if (addr_type == IPV6_ADDR_ANY ||
611             addr_type & IPV6_ADDR_MULTICAST ||
612             (!(idev->dev->flags & IFF_LOOPBACK) &&
613              addr_type & IPV6_ADDR_LOOPBACK))
614                 return ERR_PTR(-EADDRNOTAVAIL);
615
616         rcu_read_lock_bh();
617         if (idev->dead) {
618                 err = -ENODEV;                  /*XXX*/
619                 goto out2;
620         }
621
622         if (idev->cnf.disable_ipv6) {
623                 err = -EACCES;
624                 goto out2;
625         }
626
627         spin_lock(&addrconf_hash_lock);
628
629         /* Ignore adding duplicate addresses on an interface */
630         if (ipv6_chk_same_addr(dev_net(idev->dev), addr, idev->dev)) {
631                 ADBG(("ipv6_add_addr: already assigned\n"));
632                 err = -EEXIST;
633                 goto out;
634         }
635
636         ifa = kzalloc(sizeof(struct inet6_ifaddr), GFP_ATOMIC);
637
638         if (ifa == NULL) {
639                 ADBG(("ipv6_add_addr: malloc failed\n"));
640                 err = -ENOBUFS;
641                 goto out;
642         }
643
644         rt = addrconf_dst_alloc(idev, addr, 0);
645         if (IS_ERR(rt)) {
646                 err = PTR_ERR(rt);
647                 goto out;
648         }
649
650         ipv6_addr_copy(&ifa->addr, addr);
651
652         spin_lock_init(&ifa->lock);
653         spin_lock_init(&ifa->state_lock);
654         init_timer(&ifa->timer);
655         INIT_HLIST_NODE(&ifa->addr_lst);
656         ifa->timer.data = (unsigned long) ifa;
657         ifa->scope = scope;
658         ifa->prefix_len = pfxlen;
659         ifa->flags = flags | IFA_F_TENTATIVE;
660         ifa->cstamp = ifa->tstamp = jiffies;
661
662         ifa->rt = rt;
663
664         /*
665          * part one of RFC 4429, section 3.3
666          * We should not configure an address as
667          * optimistic if we do not yet know the link
668          * layer address of our nexhop router
669          */
670
671         if (rt->rt6i_nexthop == NULL)
672                 ifa->flags &= ~IFA_F_OPTIMISTIC;
673
674         ifa->idev = idev;
675         in6_dev_hold(idev);
676         /* For caller */
677         in6_ifa_hold(ifa);
678
679         /* Add to big hash table */
680         hash = ipv6_addr_hash(addr);
681
682         hlist_add_head_rcu(&ifa->addr_lst, &inet6_addr_lst[hash]);
683         spin_unlock(&addrconf_hash_lock);
684
685         write_lock(&idev->lock);
686         /* Add to inet6_dev unicast addr list. */
687         ipv6_link_dev_addr(idev, ifa);
688
689 #ifdef CONFIG_IPV6_PRIVACY
690         if (ifa->flags&IFA_F_TEMPORARY) {
691                 list_add(&ifa->tmp_list, &idev->tempaddr_list);
692                 in6_ifa_hold(ifa);
693         }
694 #endif
695
696         in6_ifa_hold(ifa);
697         write_unlock(&idev->lock);
698 out2:
699         rcu_read_unlock_bh();
700
701         if (likely(err == 0))
702                 atomic_notifier_call_chain(&inet6addr_chain, NETDEV_UP, ifa);
703         else {
704                 kfree(ifa);
705                 ifa = ERR_PTR(err);
706         }
707
708         return ifa;
709 out:
710         spin_unlock(&addrconf_hash_lock);
711         goto out2;
712 }
713
714 /* This function wants to get referenced ifp and releases it before return */
715
716 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
717 {
718         struct inet6_ifaddr *ifa, *ifn;
719         struct inet6_dev *idev = ifp->idev;
720         int state;
721         int hash;
722         int deleted = 0, onlink = 0;
723         unsigned long expires = jiffies;
724
725         hash = ipv6_addr_hash(&ifp->addr);
726
727         spin_lock_bh(&ifp->state_lock);
728         state = ifp->state;
729         ifp->state = INET6_IFADDR_STATE_DEAD;
730         spin_unlock_bh(&ifp->state_lock);
731
732         if (state == INET6_IFADDR_STATE_DEAD)
733                 goto out;
734
735         spin_lock_bh(&addrconf_hash_lock);
736         hlist_del_init_rcu(&ifp->addr_lst);
737         spin_unlock_bh(&addrconf_hash_lock);
738
739         write_lock_bh(&idev->lock);
740 #ifdef CONFIG_IPV6_PRIVACY
741         if (ifp->flags&IFA_F_TEMPORARY) {
742                 list_del(&ifp->tmp_list);
743                 if (ifp->ifpub) {
744                         in6_ifa_put(ifp->ifpub);
745                         ifp->ifpub = NULL;
746                 }
747                 __in6_ifa_put(ifp);
748         }
749 #endif
750
751         list_for_each_entry_safe(ifa, ifn, &idev->addr_list, if_list) {
752                 if (ifa == ifp) {
753                         list_del_init(&ifp->if_list);
754                         __in6_ifa_put(ifp);
755
756                         if (!(ifp->flags & IFA_F_PERMANENT) || onlink > 0)
757                                 break;
758                         deleted = 1;
759                         continue;
760                 } else if (ifp->flags & IFA_F_PERMANENT) {
761                         if (ipv6_prefix_equal(&ifa->addr, &ifp->addr,
762                                               ifp->prefix_len)) {
763                                 if (ifa->flags & IFA_F_PERMANENT) {
764                                         onlink = 1;
765                                         if (deleted)
766                                                 break;
767                                 } else {
768                                         unsigned long lifetime;
769
770                                         if (!onlink)
771                                                 onlink = -1;
772
773                                         spin_lock(&ifa->lock);
774
775                                         lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
776                                         /*
777                                          * Note: Because this address is
778                                          * not permanent, lifetime <
779                                          * LONG_MAX / HZ here.
780                                          */
781                                         if (time_before(expires,
782                                                         ifa->tstamp + lifetime * HZ))
783                                                 expires = ifa->tstamp + lifetime * HZ;
784                                         spin_unlock(&ifa->lock);
785                                 }
786                         }
787                 }
788         }
789         write_unlock_bh(&idev->lock);
790
791         addrconf_del_timer(ifp);
792
793         ipv6_ifa_notify(RTM_DELADDR, ifp);
794
795         atomic_notifier_call_chain(&inet6addr_chain, NETDEV_DOWN, ifp);
796
797         /*
798          * Purge or update corresponding prefix
799          *
800          * 1) we don't purge prefix here if address was not permanent.
801          *    prefix is managed by its own lifetime.
802          * 2) if there're no addresses, delete prefix.
803          * 3) if there're still other permanent address(es),
804          *    corresponding prefix is still permanent.
805          * 4) otherwise, update prefix lifetime to the
806          *    longest valid lifetime among the corresponding
807          *    addresses on the device.
808          *    Note: subsequent RA will update lifetime.
809          *
810          * --yoshfuji
811          */
812         if ((ifp->flags & IFA_F_PERMANENT) && onlink < 1) {
813                 struct in6_addr prefix;
814                 struct rt6_info *rt;
815                 struct net *net = dev_net(ifp->idev->dev);
816                 ipv6_addr_prefix(&prefix, &ifp->addr, ifp->prefix_len);
817                 rt = rt6_lookup(net, &prefix, NULL, ifp->idev->dev->ifindex, 1);
818
819                 if (rt && addrconf_is_prefix_route(rt)) {
820                         if (onlink == 0) {
821                                 ip6_del_rt(rt);
822                                 rt = NULL;
823                         } else if (!(rt->rt6i_flags & RTF_EXPIRES)) {
824                                 rt->rt6i_expires = expires;
825                                 rt->rt6i_flags |= RTF_EXPIRES;
826                         }
827                 }
828                 dst_release(&rt->dst);
829         }
830
831 out:
832         in6_ifa_put(ifp);
833 }
834
835 #ifdef CONFIG_IPV6_PRIVACY
836 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp, struct inet6_ifaddr *ift)
837 {
838         struct inet6_dev *idev = ifp->idev;
839         struct in6_addr addr, *tmpaddr;
840         unsigned long tmp_prefered_lft, tmp_valid_lft, tmp_cstamp, tmp_tstamp, age;
841         unsigned long regen_advance;
842         int tmp_plen;
843         int ret = 0;
844         int max_addresses;
845         u32 addr_flags;
846
847         write_lock(&idev->lock);
848         if (ift) {
849                 spin_lock_bh(&ift->lock);
850                 memcpy(&addr.s6_addr[8], &ift->addr.s6_addr[8], 8);
851                 spin_unlock_bh(&ift->lock);
852                 tmpaddr = &addr;
853         } else {
854                 tmpaddr = NULL;
855         }
856 retry:
857         in6_dev_hold(idev);
858         if (idev->cnf.use_tempaddr <= 0) {
859                 write_unlock(&idev->lock);
860                 printk(KERN_INFO
861                         "ipv6_create_tempaddr(): use_tempaddr is disabled.\n");
862                 in6_dev_put(idev);
863                 ret = -1;
864                 goto out;
865         }
866         spin_lock_bh(&ifp->lock);
867         if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
868                 idev->cnf.use_tempaddr = -1;    /*XXX*/
869                 spin_unlock_bh(&ifp->lock);
870                 write_unlock(&idev->lock);
871                 printk(KERN_WARNING
872                         "ipv6_create_tempaddr(): regeneration time exceeded. disabled temporary address support.\n");
873                 in6_dev_put(idev);
874                 ret = -1;
875                 goto out;
876         }
877         in6_ifa_hold(ifp);
878         memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
879         if (__ipv6_try_regen_rndid(idev, tmpaddr) < 0) {
880                 spin_unlock_bh(&ifp->lock);
881                 write_unlock(&idev->lock);
882                 printk(KERN_WARNING
883                         "ipv6_create_tempaddr(): regeneration of randomized interface id failed.\n");
884                 in6_ifa_put(ifp);
885                 in6_dev_put(idev);
886                 ret = -1;
887                 goto out;
888         }
889         memcpy(&addr.s6_addr[8], idev->rndid, 8);
890         age = (jiffies - ifp->tstamp) / HZ;
891         tmp_valid_lft = min_t(__u32,
892                               ifp->valid_lft,
893                               idev->cnf.temp_valid_lft + age);
894         tmp_prefered_lft = min_t(__u32,
895                                  ifp->prefered_lft,
896                                  idev->cnf.temp_prefered_lft + age -
897                                  idev->cnf.max_desync_factor);
898         tmp_plen = ifp->prefix_len;
899         max_addresses = idev->cnf.max_addresses;
900         tmp_cstamp = ifp->cstamp;
901         tmp_tstamp = ifp->tstamp;
902         spin_unlock_bh(&ifp->lock);
903
904         regen_advance = idev->cnf.regen_max_retry *
905                         idev->cnf.dad_transmits *
906                         idev->nd_parms->retrans_time / HZ;
907         write_unlock(&idev->lock);
908
909         /* A temporary address is created only if this calculated Preferred
910          * Lifetime is greater than REGEN_ADVANCE time units.  In particular,
911          * an implementation must not create a temporary address with a zero
912          * Preferred Lifetime.
913          */
914         if (tmp_prefered_lft <= regen_advance) {
915                 in6_ifa_put(ifp);
916                 in6_dev_put(idev);
917                 ret = -1;
918                 goto out;
919         }
920
921         addr_flags = IFA_F_TEMPORARY;
922         /* set in addrconf_prefix_rcv() */
923         if (ifp->flags & IFA_F_OPTIMISTIC)
924                 addr_flags |= IFA_F_OPTIMISTIC;
925
926         ift = !max_addresses ||
927               ipv6_count_addresses(idev) < max_addresses ?
928                 ipv6_add_addr(idev, &addr, tmp_plen,
929                               ipv6_addr_type(&addr)&IPV6_ADDR_SCOPE_MASK,
930                               addr_flags) : NULL;
931         if (!ift || IS_ERR(ift)) {
932                 in6_ifa_put(ifp);
933                 in6_dev_put(idev);
934                 printk(KERN_INFO
935                         "ipv6_create_tempaddr(): retry temporary address regeneration.\n");
936                 tmpaddr = &addr;
937                 write_lock(&idev->lock);
938                 goto retry;
939         }
940
941         spin_lock_bh(&ift->lock);
942         ift->ifpub = ifp;
943         ift->valid_lft = tmp_valid_lft;
944         ift->prefered_lft = tmp_prefered_lft;
945         ift->cstamp = tmp_cstamp;
946         ift->tstamp = tmp_tstamp;
947         spin_unlock_bh(&ift->lock);
948
949         addrconf_dad_start(ift, 0);
950         in6_ifa_put(ift);
951         in6_dev_put(idev);
952 out:
953         return ret;
954 }
955 #endif
956
957 /*
958  *      Choose an appropriate source address (RFC3484)
959  */
960 enum {
961         IPV6_SADDR_RULE_INIT = 0,
962         IPV6_SADDR_RULE_LOCAL,
963         IPV6_SADDR_RULE_SCOPE,
964         IPV6_SADDR_RULE_PREFERRED,
965 #ifdef CONFIG_IPV6_MIP6
966         IPV6_SADDR_RULE_HOA,
967 #endif
968         IPV6_SADDR_RULE_OIF,
969         IPV6_SADDR_RULE_LABEL,
970 #ifdef CONFIG_IPV6_PRIVACY
971         IPV6_SADDR_RULE_PRIVACY,
972 #endif
973         IPV6_SADDR_RULE_ORCHID,
974         IPV6_SADDR_RULE_PREFIX,
975         IPV6_SADDR_RULE_MAX
976 };
977
978 struct ipv6_saddr_score {
979         int                     rule;
980         int                     addr_type;
981         struct inet6_ifaddr     *ifa;
982         DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
983         int                     scopedist;
984         int                     matchlen;
985 };
986
987 struct ipv6_saddr_dst {
988         const struct in6_addr *addr;
989         int ifindex;
990         int scope;
991         int label;
992         unsigned int prefs;
993 };
994
995 static inline int ipv6_saddr_preferred(int type)
996 {
997         if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
998                 return 1;
999         return 0;
1000 }
1001
1002 static int ipv6_get_saddr_eval(struct net *net,
1003                                struct ipv6_saddr_score *score,
1004                                struct ipv6_saddr_dst *dst,
1005                                int i)
1006 {
1007         int ret;
1008
1009         if (i <= score->rule) {
1010                 switch (i) {
1011                 case IPV6_SADDR_RULE_SCOPE:
1012                         ret = score->scopedist;
1013                         break;
1014                 case IPV6_SADDR_RULE_PREFIX:
1015                         ret = score->matchlen;
1016                         break;
1017                 default:
1018                         ret = !!test_bit(i, score->scorebits);
1019                 }
1020                 goto out;
1021         }
1022
1023         switch (i) {
1024         case IPV6_SADDR_RULE_INIT:
1025                 /* Rule 0: remember if hiscore is not ready yet */
1026                 ret = !!score->ifa;
1027                 break;
1028         case IPV6_SADDR_RULE_LOCAL:
1029                 /* Rule 1: Prefer same address */
1030                 ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1031                 break;
1032         case IPV6_SADDR_RULE_SCOPE:
1033                 /* Rule 2: Prefer appropriate scope
1034                  *
1035                  *      ret
1036                  *       ^
1037                  *    -1 |  d 15
1038                  *    ---+--+-+---> scope
1039                  *       |
1040                  *       |             d is scope of the destination.
1041                  *  B-d  |  \
1042                  *       |   \      <- smaller scope is better if
1043                  *  B-15 |    \        if scope is enough for destinaion.
1044                  *       |             ret = B - scope (-1 <= scope >= d <= 15).
1045                  * d-C-1 | /
1046                  *       |/         <- greater is better
1047                  *   -C  /             if scope is not enough for destination.
1048                  *      /|             ret = scope - C (-1 <= d < scope <= 15).
1049                  *
1050                  * d - C - 1 < B -15 (for all -1 <= d <= 15).
1051                  * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1052                  * Assume B = 0 and we get C > 29.
1053                  */
1054                 ret = __ipv6_addr_src_scope(score->addr_type);
1055                 if (ret >= dst->scope)
1056                         ret = -ret;
1057                 else
1058                         ret -= 128;     /* 30 is enough */
1059                 score->scopedist = ret;
1060                 break;
1061         case IPV6_SADDR_RULE_PREFERRED:
1062                 /* Rule 3: Avoid deprecated and optimistic addresses */
1063                 ret = ipv6_saddr_preferred(score->addr_type) ||
1064                       !(score->ifa->flags & (IFA_F_DEPRECATED|IFA_F_OPTIMISTIC));
1065                 break;
1066 #ifdef CONFIG_IPV6_MIP6
1067         case IPV6_SADDR_RULE_HOA:
1068             {
1069                 /* Rule 4: Prefer home address */
1070                 int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1071                 ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1072                 break;
1073             }
1074 #endif
1075         case IPV6_SADDR_RULE_OIF:
1076                 /* Rule 5: Prefer outgoing interface */
1077                 ret = (!dst->ifindex ||
1078                        dst->ifindex == score->ifa->idev->dev->ifindex);
1079                 break;
1080         case IPV6_SADDR_RULE_LABEL:
1081                 /* Rule 6: Prefer matching label */
1082                 ret = ipv6_addr_label(net,
1083                                       &score->ifa->addr, score->addr_type,
1084                                       score->ifa->idev->dev->ifindex) == dst->label;
1085                 break;
1086 #ifdef CONFIG_IPV6_PRIVACY
1087         case IPV6_SADDR_RULE_PRIVACY:
1088             {
1089                 /* Rule 7: Prefer public address
1090                  * Note: prefer temprary address if use_tempaddr >= 2
1091                  */
1092                 int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1093                                 !!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1094                                 score->ifa->idev->cnf.use_tempaddr >= 2;
1095                 ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1096                 break;
1097             }
1098 #endif
1099         case IPV6_SADDR_RULE_ORCHID:
1100                 /* Rule 8-: Prefer ORCHID vs ORCHID or
1101                  *          non-ORCHID vs non-ORCHID
1102                  */
1103                 ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1104                         ipv6_addr_orchid(dst->addr));
1105                 break;
1106         case IPV6_SADDR_RULE_PREFIX:
1107                 /* Rule 8: Use longest matching prefix */
1108                 score->matchlen = ret = ipv6_addr_diff(&score->ifa->addr,
1109                                                        dst->addr);
1110                 break;
1111         default:
1112                 ret = 0;
1113         }
1114
1115         if (ret)
1116                 __set_bit(i, score->scorebits);
1117         score->rule = i;
1118 out:
1119         return ret;
1120 }
1121
1122 int ipv6_dev_get_saddr(struct net *net, struct net_device *dst_dev,
1123                        const struct in6_addr *daddr, unsigned int prefs,
1124                        struct in6_addr *saddr)
1125 {
1126         struct ipv6_saddr_score scores[2],
1127                                 *score = &scores[0], *hiscore = &scores[1];
1128         struct ipv6_saddr_dst dst;
1129         struct net_device *dev;
1130         int dst_type;
1131
1132         dst_type = __ipv6_addr_type(daddr);
1133         dst.addr = daddr;
1134         dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1135         dst.scope = __ipv6_addr_src_scope(dst_type);
1136         dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1137         dst.prefs = prefs;
1138
1139         hiscore->rule = -1;
1140         hiscore->ifa = NULL;
1141
1142         rcu_read_lock();
1143
1144         for_each_netdev_rcu(net, dev) {
1145                 struct inet6_dev *idev;
1146
1147                 /* Candidate Source Address (section 4)
1148                  *  - multicast and link-local destination address,
1149                  *    the set of candidate source address MUST only
1150                  *    include addresses assigned to interfaces
1151                  *    belonging to the same link as the outgoing
1152                  *    interface.
1153                  * (- For site-local destination addresses, the
1154                  *    set of candidate source addresses MUST only
1155                  *    include addresses assigned to interfaces
1156                  *    belonging to the same site as the outgoing
1157                  *    interface.)
1158                  */
1159                 if (((dst_type & IPV6_ADDR_MULTICAST) ||
1160                      dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL) &&
1161                     dst.ifindex && dev->ifindex != dst.ifindex)
1162                         continue;
1163
1164                 idev = __in6_dev_get(dev);
1165                 if (!idev)
1166                         continue;
1167
1168                 read_lock_bh(&idev->lock);
1169                 list_for_each_entry(score->ifa, &idev->addr_list, if_list) {
1170                         int i;
1171
1172                         /*
1173                          * - Tentative Address (RFC2462 section 5.4)
1174                          *  - A tentative address is not considered
1175                          *    "assigned to an interface" in the traditional
1176                          *    sense, unless it is also flagged as optimistic.
1177                          * - Candidate Source Address (section 4)
1178                          *  - In any case, anycast addresses, multicast
1179                          *    addresses, and the unspecified address MUST
1180                          *    NOT be included in a candidate set.
1181                          */
1182                         if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1183                             (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1184                                 continue;
1185
1186                         score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1187
1188                         if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1189                                      score->addr_type & IPV6_ADDR_MULTICAST)) {
1190                                 LIMIT_NETDEBUG(KERN_DEBUG
1191                                                "ADDRCONF: unspecified / multicast address "
1192                                                "assigned as unicast address on %s",
1193                                                dev->name);
1194                                 continue;
1195                         }
1196
1197                         score->rule = -1;
1198                         bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1199
1200                         for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1201                                 int minihiscore, miniscore;
1202
1203                                 minihiscore = ipv6_get_saddr_eval(net, hiscore, &dst, i);
1204                                 miniscore = ipv6_get_saddr_eval(net, score, &dst, i);
1205
1206                                 if (minihiscore > miniscore) {
1207                                         if (i == IPV6_SADDR_RULE_SCOPE &&
1208                                             score->scopedist > 0) {
1209                                                 /*
1210                                                  * special case:
1211                                                  * each remaining entry
1212                                                  * has too small (not enough)
1213                                                  * scope, because ifa entries
1214                                                  * are sorted by their scope
1215                                                  * values.
1216                                                  */
1217                                                 goto try_nextdev;
1218                                         }
1219                                         break;
1220                                 } else if (minihiscore < miniscore) {
1221                                         if (hiscore->ifa)
1222                                                 in6_ifa_put(hiscore->ifa);
1223
1224                                         in6_ifa_hold(score->ifa);
1225
1226                                         swap(hiscore, score);
1227
1228                                         /* restore our iterator */
1229                                         score->ifa = hiscore->ifa;
1230
1231                                         break;
1232                                 }
1233                         }
1234                 }
1235 try_nextdev:
1236                 read_unlock_bh(&idev->lock);
1237         }
1238         rcu_read_unlock();
1239
1240         if (!hiscore->ifa)
1241                 return -EADDRNOTAVAIL;
1242
1243         ipv6_addr_copy(saddr, &hiscore->ifa->addr);
1244         in6_ifa_put(hiscore->ifa);
1245         return 0;
1246 }
1247 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1248
1249 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1250                     unsigned char banned_flags)
1251 {
1252         struct inet6_dev *idev;
1253         int err = -EADDRNOTAVAIL;
1254
1255         rcu_read_lock();
1256         idev = __in6_dev_get(dev);
1257         if (idev) {
1258                 struct inet6_ifaddr *ifp;
1259
1260                 read_lock_bh(&idev->lock);
1261                 list_for_each_entry(ifp, &idev->addr_list, if_list) {
1262                         if (ifp->scope == IFA_LINK &&
1263                             !(ifp->flags & banned_flags)) {
1264                                 ipv6_addr_copy(addr, &ifp->addr);
1265                                 err = 0;
1266                                 break;
1267                         }
1268                 }
1269                 read_unlock_bh(&idev->lock);
1270         }
1271         rcu_read_unlock();
1272         return err;
1273 }
1274
1275 static int ipv6_count_addresses(struct inet6_dev *idev)
1276 {
1277         int cnt = 0;
1278         struct inet6_ifaddr *ifp;
1279
1280         read_lock_bh(&idev->lock);
1281         list_for_each_entry(ifp, &idev->addr_list, if_list)
1282                 cnt++;
1283         read_unlock_bh(&idev->lock);
1284         return cnt;
1285 }
1286
1287 int ipv6_chk_addr(struct net *net, struct in6_addr *addr,
1288                   struct net_device *dev, int strict)
1289 {
1290         struct inet6_ifaddr *ifp;
1291         struct hlist_node *node;
1292         unsigned int hash = ipv6_addr_hash(addr);
1293
1294         rcu_read_lock_bh();
1295         hlist_for_each_entry_rcu(ifp, node, &inet6_addr_lst[hash], addr_lst) {
1296                 if (!net_eq(dev_net(ifp->idev->dev), net))
1297                         continue;
1298                 if (ipv6_addr_equal(&ifp->addr, addr) &&
1299                     !(ifp->flags&IFA_F_TENTATIVE) &&
1300                     (dev == NULL || ifp->idev->dev == dev ||
1301                      !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1302                         rcu_read_unlock_bh();
1303                         return 1;
1304                 }
1305         }
1306
1307         rcu_read_unlock_bh();
1308         return 0;
1309 }
1310 EXPORT_SYMBOL(ipv6_chk_addr);
1311
1312 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
1313                                struct net_device *dev)
1314 {
1315         unsigned int hash = ipv6_addr_hash(addr);
1316         struct inet6_ifaddr *ifp;
1317         struct hlist_node *node;
1318
1319         hlist_for_each_entry(ifp, node, &inet6_addr_lst[hash], addr_lst) {
1320                 if (!net_eq(dev_net(ifp->idev->dev), net))
1321                         continue;
1322                 if (ipv6_addr_equal(&ifp->addr, addr)) {
1323                         if (dev == NULL || ifp->idev->dev == dev)
1324                                 return true;
1325                 }
1326         }
1327         return false;
1328 }
1329
1330 int ipv6_chk_prefix(struct in6_addr *addr, struct net_device *dev)
1331 {
1332         struct inet6_dev *idev;
1333         struct inet6_ifaddr *ifa;
1334         int     onlink;
1335
1336         onlink = 0;
1337         rcu_read_lock();
1338         idev = __in6_dev_get(dev);
1339         if (idev) {
1340                 read_lock_bh(&idev->lock);
1341                 list_for_each_entry(ifa, &idev->addr_list, if_list) {
1342                         onlink = ipv6_prefix_equal(addr, &ifa->addr,
1343                                                    ifa->prefix_len);
1344                         if (onlink)
1345                                 break;
1346                 }
1347                 read_unlock_bh(&idev->lock);
1348         }
1349         rcu_read_unlock();
1350         return onlink;
1351 }
1352
1353 EXPORT_SYMBOL(ipv6_chk_prefix);
1354
1355 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
1356                                      struct net_device *dev, int strict)
1357 {
1358         struct inet6_ifaddr *ifp, *result = NULL;
1359         unsigned int hash = ipv6_addr_hash(addr);
1360         struct hlist_node *node;
1361
1362         rcu_read_lock_bh();
1363         hlist_for_each_entry_rcu_bh(ifp, node, &inet6_addr_lst[hash], addr_lst) {
1364                 if (!net_eq(dev_net(ifp->idev->dev), net))
1365                         continue;
1366                 if (ipv6_addr_equal(&ifp->addr, addr)) {
1367                         if (dev == NULL || ifp->idev->dev == dev ||
1368                             !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
1369                                 result = ifp;
1370                                 in6_ifa_hold(ifp);
1371                                 break;
1372                         }
1373                 }
1374         }
1375         rcu_read_unlock_bh();
1376
1377         return result;
1378 }
1379
1380 /* Gets referenced address, destroys ifaddr */
1381
1382 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
1383 {
1384         if (ifp->flags&IFA_F_PERMANENT) {
1385                 spin_lock_bh(&ifp->lock);
1386                 addrconf_del_timer(ifp);
1387                 ifp->flags |= IFA_F_TENTATIVE;
1388                 if (dad_failed)
1389                         ifp->flags |= IFA_F_DADFAILED;
1390                 spin_unlock_bh(&ifp->lock);
1391                 if (dad_failed)
1392                         ipv6_ifa_notify(0, ifp);
1393                 in6_ifa_put(ifp);
1394 #ifdef CONFIG_IPV6_PRIVACY
1395         } else if (ifp->flags&IFA_F_TEMPORARY) {
1396                 struct inet6_ifaddr *ifpub;
1397                 spin_lock_bh(&ifp->lock);
1398                 ifpub = ifp->ifpub;
1399                 if (ifpub) {
1400                         in6_ifa_hold(ifpub);
1401                         spin_unlock_bh(&ifp->lock);
1402                         ipv6_create_tempaddr(ifpub, ifp);
1403                         in6_ifa_put(ifpub);
1404                 } else {
1405                         spin_unlock_bh(&ifp->lock);
1406                 }
1407                 ipv6_del_addr(ifp);
1408 #endif
1409         } else
1410                 ipv6_del_addr(ifp);
1411 }
1412
1413 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
1414 {
1415         int err = -ENOENT;
1416
1417         spin_lock(&ifp->state_lock);
1418         if (ifp->state == INET6_IFADDR_STATE_DAD) {
1419                 ifp->state = INET6_IFADDR_STATE_POSTDAD;
1420                 err = 0;
1421         }
1422         spin_unlock(&ifp->state_lock);
1423
1424         return err;
1425 }
1426
1427 void addrconf_dad_failure(struct inet6_ifaddr *ifp)
1428 {
1429         struct inet6_dev *idev = ifp->idev;
1430
1431         if (addrconf_dad_end(ifp)) {
1432                 in6_ifa_put(ifp);
1433                 return;
1434         }
1435
1436         if (net_ratelimit())
1437                 printk(KERN_INFO "%s: IPv6 duplicate address %pI6c detected!\n",
1438                         ifp->idev->dev->name, &ifp->addr);
1439
1440         if (idev->cnf.accept_dad > 1 && !idev->cnf.disable_ipv6) {
1441                 struct in6_addr addr;
1442
1443                 addr.s6_addr32[0] = htonl(0xfe800000);
1444                 addr.s6_addr32[1] = 0;
1445
1446                 if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
1447                     ipv6_addr_equal(&ifp->addr, &addr)) {
1448                         /* DAD failed for link-local based on MAC address */
1449                         idev->cnf.disable_ipv6 = 1;
1450
1451                         printk(KERN_INFO "%s: IPv6 being disabled!\n",
1452                                 ifp->idev->dev->name);
1453                 }
1454         }
1455
1456         addrconf_dad_stop(ifp, 1);
1457 }
1458
1459 /* Join to solicited addr multicast group. */
1460
1461 void addrconf_join_solict(struct net_device *dev, struct in6_addr *addr)
1462 {
1463         struct in6_addr maddr;
1464
1465         if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
1466                 return;
1467
1468         addrconf_addr_solict_mult(addr, &maddr);
1469         ipv6_dev_mc_inc(dev, &maddr);
1470 }
1471
1472 void addrconf_leave_solict(struct inet6_dev *idev, struct in6_addr *addr)
1473 {
1474         struct in6_addr maddr;
1475
1476         if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
1477                 return;
1478
1479         addrconf_addr_solict_mult(addr, &maddr);
1480         __ipv6_dev_mc_dec(idev, &maddr);
1481 }
1482
1483 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
1484 {
1485         struct in6_addr addr;
1486         ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
1487         if (ipv6_addr_any(&addr))
1488                 return;
1489         ipv6_dev_ac_inc(ifp->idev->dev, &addr);
1490 }
1491
1492 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
1493 {
1494         struct in6_addr addr;
1495         ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
1496         if (ipv6_addr_any(&addr))
1497                 return;
1498         __ipv6_dev_ac_dec(ifp->idev, &addr);
1499 }
1500
1501 static int addrconf_ifid_eui48(u8 *eui, struct net_device *dev)
1502 {
1503         if (dev->addr_len != ETH_ALEN)
1504                 return -1;
1505         memcpy(eui, dev->dev_addr, 3);
1506         memcpy(eui + 5, dev->dev_addr + 3, 3);
1507
1508         /*
1509          * The zSeries OSA network cards can be shared among various
1510          * OS instances, but the OSA cards have only one MAC address.
1511          * This leads to duplicate address conflicts in conjunction
1512          * with IPv6 if more than one instance uses the same card.
1513          *
1514          * The driver for these cards can deliver a unique 16-bit
1515          * identifier for each instance sharing the same card.  It is
1516          * placed instead of 0xFFFE in the interface identifier.  The
1517          * "u" bit of the interface identifier is not inverted in this
1518          * case.  Hence the resulting interface identifier has local
1519          * scope according to RFC2373.
1520          */
1521         if (dev->dev_id) {
1522                 eui[3] = (dev->dev_id >> 8) & 0xFF;
1523                 eui[4] = dev->dev_id & 0xFF;
1524         } else {
1525                 eui[3] = 0xFF;
1526                 eui[4] = 0xFE;
1527                 eui[0] ^= 2;
1528         }
1529         return 0;
1530 }
1531
1532 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
1533 {
1534         /* XXX: inherit EUI-64 from other interface -- yoshfuji */
1535         if (dev->addr_len != ARCNET_ALEN)
1536                 return -1;
1537         memset(eui, 0, 7);
1538         eui[7] = *(u8*)dev->dev_addr;
1539         return 0;
1540 }
1541
1542 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
1543 {
1544         if (dev->addr_len != INFINIBAND_ALEN)
1545                 return -1;
1546         memcpy(eui, dev->dev_addr + 12, 8);
1547         eui[0] |= 2;
1548         return 0;
1549 }
1550
1551 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
1552 {
1553         if (addr == 0)
1554                 return -1;
1555         eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
1556                   ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
1557                   ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
1558                   ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
1559                   ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
1560                   ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
1561         eui[1] = 0;
1562         eui[2] = 0x5E;
1563         eui[3] = 0xFE;
1564         memcpy(eui + 4, &addr, 4);
1565         return 0;
1566 }
1567
1568 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
1569 {
1570         if (dev->priv_flags & IFF_ISATAP)
1571                 return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
1572         return -1;
1573 }
1574
1575 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
1576 {
1577         switch (dev->type) {
1578         case ARPHRD_ETHER:
1579         case ARPHRD_FDDI:
1580         case ARPHRD_IEEE802_TR:
1581                 return addrconf_ifid_eui48(eui, dev);
1582         case ARPHRD_ARCNET:
1583                 return addrconf_ifid_arcnet(eui, dev);
1584         case ARPHRD_INFINIBAND:
1585                 return addrconf_ifid_infiniband(eui, dev);
1586         case ARPHRD_SIT:
1587                 return addrconf_ifid_sit(eui, dev);
1588         }
1589         return -1;
1590 }
1591
1592 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
1593 {
1594         int err = -1;
1595         struct inet6_ifaddr *ifp;
1596
1597         read_lock_bh(&idev->lock);
1598         list_for_each_entry(ifp, &idev->addr_list, if_list) {
1599                 if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
1600                         memcpy(eui, ifp->addr.s6_addr+8, 8);
1601                         err = 0;
1602                         break;
1603                 }
1604         }
1605         read_unlock_bh(&idev->lock);
1606         return err;
1607 }
1608
1609 #ifdef CONFIG_IPV6_PRIVACY
1610 /* (re)generation of randomized interface identifier (RFC 3041 3.2, 3.5) */
1611 static int __ipv6_regen_rndid(struct inet6_dev *idev)
1612 {
1613 regen:
1614         get_random_bytes(idev->rndid, sizeof(idev->rndid));
1615         idev->rndid[0] &= ~0x02;
1616
1617         /*
1618          * <draft-ietf-ipngwg-temp-addresses-v2-00.txt>:
1619          * check if generated address is not inappropriate
1620          *
1621          *  - Reserved subnet anycast (RFC 2526)
1622          *      11111101 11....11 1xxxxxxx
1623          *  - ISATAP (RFC4214) 6.1
1624          *      00-00-5E-FE-xx-xx-xx-xx
1625          *  - value 0
1626          *  - XXX: already assigned to an address on the device
1627          */
1628         if (idev->rndid[0] == 0xfd &&
1629             (idev->rndid[1]&idev->rndid[2]&idev->rndid[3]&idev->rndid[4]&idev->rndid[5]&idev->rndid[6]) == 0xff &&
1630             (idev->rndid[7]&0x80))
1631                 goto regen;
1632         if ((idev->rndid[0]|idev->rndid[1]) == 0) {
1633                 if (idev->rndid[2] == 0x5e && idev->rndid[3] == 0xfe)
1634                         goto regen;
1635                 if ((idev->rndid[2]|idev->rndid[3]|idev->rndid[4]|idev->rndid[5]|idev->rndid[6]|idev->rndid[7]) == 0x00)
1636                         goto regen;
1637         }
1638
1639         return 0;
1640 }
1641
1642 static void ipv6_regen_rndid(unsigned long data)
1643 {
1644         struct inet6_dev *idev = (struct inet6_dev *) data;
1645         unsigned long expires;
1646
1647         rcu_read_lock_bh();
1648         write_lock_bh(&idev->lock);
1649
1650         if (idev->dead)
1651                 goto out;
1652
1653         if (__ipv6_regen_rndid(idev) < 0)
1654                 goto out;
1655
1656         expires = jiffies +
1657                 idev->cnf.temp_prefered_lft * HZ -
1658                 idev->cnf.regen_max_retry * idev->cnf.dad_transmits * idev->nd_parms->retrans_time -
1659                 idev->cnf.max_desync_factor * HZ;
1660         if (time_before(expires, jiffies)) {
1661                 printk(KERN_WARNING
1662                         "ipv6_regen_rndid(): too short regeneration interval; timer disabled for %s.\n",
1663                         idev->dev->name);
1664                 goto out;
1665         }
1666
1667         if (!mod_timer(&idev->regen_timer, expires))
1668                 in6_dev_hold(idev);
1669
1670 out:
1671         write_unlock_bh(&idev->lock);
1672         rcu_read_unlock_bh();
1673         in6_dev_put(idev);
1674 }
1675
1676 static int __ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr) {
1677         int ret = 0;
1678
1679         if (tmpaddr && memcmp(idev->rndid, &tmpaddr->s6_addr[8], 8) == 0)
1680                 ret = __ipv6_regen_rndid(idev);
1681         return ret;
1682 }
1683 #endif
1684
1685 /*
1686  *      Add prefix route.
1687  */
1688
1689 static void
1690 addrconf_prefix_route(struct in6_addr *pfx, int plen, struct net_device *dev,
1691                       unsigned long expires, u32 flags)
1692 {
1693         struct fib6_config cfg = {
1694                 .fc_table = RT6_TABLE_PREFIX,
1695                 .fc_metric = IP6_RT_PRIO_ADDRCONF,
1696                 .fc_ifindex = dev->ifindex,
1697                 .fc_expires = expires,
1698                 .fc_dst_len = plen,
1699                 .fc_flags = RTF_UP | flags,
1700                 .fc_nlinfo.nl_net = dev_net(dev),
1701                 .fc_protocol = RTPROT_KERNEL,
1702         };
1703
1704         ipv6_addr_copy(&cfg.fc_dst, pfx);
1705
1706         /* Prevent useless cloning on PtP SIT.
1707            This thing is done here expecting that the whole
1708            class of non-broadcast devices need not cloning.
1709          */
1710 #if defined(CONFIG_IPV6_SIT) || defined(CONFIG_IPV6_SIT_MODULE)
1711         if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
1712                 cfg.fc_flags |= RTF_NONEXTHOP;
1713 #endif
1714
1715         ip6_route_add(&cfg);
1716 }
1717
1718 /* Create "default" multicast route to the interface */
1719
1720 static void addrconf_add_mroute(struct net_device *dev)
1721 {
1722         struct fib6_config cfg = {
1723                 .fc_table = RT6_TABLE_LOCAL,
1724                 .fc_metric = IP6_RT_PRIO_ADDRCONF,
1725                 .fc_ifindex = dev->ifindex,
1726                 .fc_dst_len = 8,
1727                 .fc_flags = RTF_UP,
1728                 .fc_nlinfo.nl_net = dev_net(dev),
1729         };
1730
1731         ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
1732
1733         ip6_route_add(&cfg);
1734 }
1735
1736 #if defined(CONFIG_IPV6_SIT) || defined(CONFIG_IPV6_SIT_MODULE)
1737 static void sit_route_add(struct net_device *dev)
1738 {
1739         struct fib6_config cfg = {
1740                 .fc_table = RT6_TABLE_MAIN,
1741                 .fc_metric = IP6_RT_PRIO_ADDRCONF,
1742                 .fc_ifindex = dev->ifindex,
1743                 .fc_dst_len = 96,
1744                 .fc_flags = RTF_UP | RTF_NONEXTHOP,
1745                 .fc_nlinfo.nl_net = dev_net(dev),
1746         };
1747
1748         /* prefix length - 96 bits "::d.d.d.d" */
1749         ip6_route_add(&cfg);
1750 }
1751 #endif
1752
1753 static void addrconf_add_lroute(struct net_device *dev)
1754 {
1755         struct in6_addr addr;
1756
1757         ipv6_addr_set(&addr,  htonl(0xFE800000), 0, 0, 0);
1758         addrconf_prefix_route(&addr, 64, dev, 0, 0);
1759 }
1760
1761 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
1762 {
1763         struct inet6_dev *idev;
1764
1765         ASSERT_RTNL();
1766
1767         idev = ipv6_find_idev(dev);
1768         if (!idev)
1769                 return ERR_PTR(-ENOBUFS);
1770
1771         if (idev->cnf.disable_ipv6)
1772                 return ERR_PTR(-EACCES);
1773
1774         /* Add default multicast route */
1775         addrconf_add_mroute(dev);
1776
1777         /* Add link local route */
1778         addrconf_add_lroute(dev);
1779         return idev;
1780 }
1781
1782 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len)
1783 {
1784         struct prefix_info *pinfo;
1785         __u32 valid_lft;
1786         __u32 prefered_lft;
1787         int addr_type;
1788         struct inet6_dev *in6_dev;
1789         struct net *net = dev_net(dev);
1790
1791         pinfo = (struct prefix_info *) opt;
1792
1793         if (len < sizeof(struct prefix_info)) {
1794                 ADBG(("addrconf: prefix option too short\n"));
1795                 return;
1796         }
1797
1798         /*
1799          *      Validation checks ([ADDRCONF], page 19)
1800          */
1801
1802         addr_type = ipv6_addr_type(&pinfo->prefix);
1803
1804         if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
1805                 return;
1806
1807         valid_lft = ntohl(pinfo->valid);
1808         prefered_lft = ntohl(pinfo->prefered);
1809
1810         if (prefered_lft > valid_lft) {
1811                 if (net_ratelimit())
1812                         printk(KERN_WARNING "addrconf: prefix option has invalid lifetime\n");
1813                 return;
1814         }
1815
1816         in6_dev = in6_dev_get(dev);
1817
1818         if (in6_dev == NULL) {
1819                 if (net_ratelimit())
1820                         printk(KERN_DEBUG "addrconf: device %s not configured\n", dev->name);
1821                 return;
1822         }
1823
1824         /*
1825          *      Two things going on here:
1826          *      1) Add routes for on-link prefixes
1827          *      2) Configure prefixes with the auto flag set
1828          */
1829
1830         if (pinfo->onlink) {
1831                 struct rt6_info *rt;
1832                 unsigned long rt_expires;
1833
1834                 /* Avoid arithmetic overflow. Really, we could
1835                  * save rt_expires in seconds, likely valid_lft,
1836                  * but it would require division in fib gc, that it
1837                  * not good.
1838                  */
1839                 if (HZ > USER_HZ)
1840                         rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
1841                 else
1842                         rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
1843
1844                 if (addrconf_finite_timeout(rt_expires))
1845                         rt_expires *= HZ;
1846
1847                 rt = rt6_lookup(net, &pinfo->prefix, NULL,
1848                                 dev->ifindex, 1);
1849
1850                 if (rt && addrconf_is_prefix_route(rt)) {
1851                         /* Autoconf prefix route */
1852                         if (valid_lft == 0) {
1853                                 ip6_del_rt(rt);
1854                                 rt = NULL;
1855                         } else if (addrconf_finite_timeout(rt_expires)) {
1856                                 /* not infinity */
1857                                 rt->rt6i_expires = jiffies + rt_expires;
1858                                 rt->rt6i_flags |= RTF_EXPIRES;
1859                         } else {
1860                                 rt->rt6i_flags &= ~RTF_EXPIRES;
1861                                 rt->rt6i_expires = 0;
1862                         }
1863                 } else if (valid_lft) {
1864                         clock_t expires = 0;
1865                         int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
1866                         if (addrconf_finite_timeout(rt_expires)) {
1867                                 /* not infinity */
1868                                 flags |= RTF_EXPIRES;
1869                                 expires = jiffies_to_clock_t(rt_expires);
1870                         }
1871                         addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
1872                                               dev, expires, flags);
1873                 }
1874                 if (rt)
1875                         dst_release(&rt->dst);
1876         }
1877
1878         /* Try to figure out our local address for this prefix */
1879
1880         if (pinfo->autoconf && in6_dev->cnf.autoconf) {
1881                 struct inet6_ifaddr * ifp;
1882                 struct in6_addr addr;
1883                 int create = 0, update_lft = 0;
1884
1885                 if (pinfo->prefix_len == 64) {
1886                         memcpy(&addr, &pinfo->prefix, 8);
1887                         if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
1888                             ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
1889                                 in6_dev_put(in6_dev);
1890                                 return;
1891                         }
1892                         goto ok;
1893                 }
1894                 if (net_ratelimit())
1895                         printk(KERN_DEBUG "IPv6 addrconf: prefix with wrong length %d\n",
1896                                pinfo->prefix_len);
1897                 in6_dev_put(in6_dev);
1898                 return;
1899
1900 ok:
1901
1902                 ifp = ipv6_get_ifaddr(net, &addr, dev, 1);
1903
1904                 if (ifp == NULL && valid_lft) {
1905                         int max_addresses = in6_dev->cnf.max_addresses;
1906                         u32 addr_flags = 0;
1907
1908 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1909                         if (in6_dev->cnf.optimistic_dad &&
1910                             !net->ipv6.devconf_all->forwarding)
1911                                 addr_flags = IFA_F_OPTIMISTIC;
1912 #endif
1913
1914                         /* Do not allow to create too much of autoconfigured
1915                          * addresses; this would be too easy way to crash kernel.
1916                          */
1917                         if (!max_addresses ||
1918                             ipv6_count_addresses(in6_dev) < max_addresses)
1919                                 ifp = ipv6_add_addr(in6_dev, &addr, pinfo->prefix_len,
1920                                                     addr_type&IPV6_ADDR_SCOPE_MASK,
1921                                                     addr_flags);
1922
1923                         if (!ifp || IS_ERR(ifp)) {
1924                                 in6_dev_put(in6_dev);
1925                                 return;
1926                         }
1927
1928                         update_lft = create = 1;
1929                         ifp->cstamp = jiffies;
1930                         addrconf_dad_start(ifp, RTF_ADDRCONF|RTF_PREFIX_RT);
1931                 }
1932
1933                 if (ifp) {
1934                         int flags;
1935                         unsigned long now;
1936 #ifdef CONFIG_IPV6_PRIVACY
1937                         struct inet6_ifaddr *ift;
1938 #endif
1939                         u32 stored_lft;
1940
1941                         /* update lifetime (RFC2462 5.5.3 e) */
1942                         spin_lock(&ifp->lock);
1943                         now = jiffies;
1944                         if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
1945                                 stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
1946                         else
1947                                 stored_lft = 0;
1948                         if (!update_lft && stored_lft) {
1949                                 if (valid_lft > MIN_VALID_LIFETIME ||
1950                                     valid_lft > stored_lft)
1951                                         update_lft = 1;
1952                                 else if (stored_lft <= MIN_VALID_LIFETIME) {
1953                                         /* valid_lft <= stored_lft is always true */
1954                                         /*
1955                                          * RFC 4862 Section 5.5.3e:
1956                                          * "Note that the preferred lifetime of
1957                                          *  the corresponding address is always
1958                                          *  reset to the Preferred Lifetime in
1959                                          *  the received Prefix Information
1960                                          *  option, regardless of whether the
1961                                          *  valid lifetime is also reset or
1962                                          *  ignored."
1963                                          *
1964                                          *  So if the preferred lifetime in
1965                                          *  this advertisement is different
1966                                          *  than what we have stored, but the
1967                                          *  valid lifetime is invalid, just
1968                                          *  reset prefered_lft.
1969                                          *
1970                                          *  We must set the valid lifetime
1971                                          *  to the stored lifetime since we'll
1972                                          *  be updating the timestamp below,
1973                                          *  else we'll set it back to the
1974                                          *  minumum.
1975                                          */
1976                                         if (prefered_lft != ifp->prefered_lft) {
1977                                                 valid_lft = stored_lft;
1978                                                 update_lft = 1;
1979                                         }
1980                                 } else {
1981                                         valid_lft = MIN_VALID_LIFETIME;
1982                                         if (valid_lft < prefered_lft)
1983                                                 prefered_lft = valid_lft;
1984                                         update_lft = 1;
1985                                 }
1986                         }
1987
1988                         if (update_lft) {
1989                                 ifp->valid_lft = valid_lft;
1990                                 ifp->prefered_lft = prefered_lft;
1991                                 ifp->tstamp = now;
1992                                 flags = ifp->flags;
1993                                 ifp->flags &= ~IFA_F_DEPRECATED;
1994                                 spin_unlock(&ifp->lock);
1995
1996                                 if (!(flags&IFA_F_TENTATIVE))
1997                                         ipv6_ifa_notify(0, ifp);
1998                         } else
1999                                 spin_unlock(&ifp->lock);
2000
2001 #ifdef CONFIG_IPV6_PRIVACY
2002                         read_lock_bh(&in6_dev->lock);
2003                         /* update all temporary addresses in the list */
2004                         list_for_each_entry(ift, &in6_dev->tempaddr_list, tmp_list) {
2005                                 /*
2006                                  * When adjusting the lifetimes of an existing
2007                                  * temporary address, only lower the lifetimes.
2008                                  * Implementations must not increase the
2009                                  * lifetimes of an existing temporary address
2010                                  * when processing a Prefix Information Option.
2011                                  */
2012                                 if (ifp != ift->ifpub)
2013                                         continue;
2014
2015                                 spin_lock(&ift->lock);
2016                                 flags = ift->flags;
2017                                 if (ift->valid_lft > valid_lft &&
2018                                     ift->valid_lft - valid_lft > (jiffies - ift->tstamp) / HZ)
2019                                         ift->valid_lft = valid_lft + (jiffies - ift->tstamp) / HZ;
2020                                 if (ift->prefered_lft > prefered_lft &&
2021                                     ift->prefered_lft - prefered_lft > (jiffies - ift->tstamp) / HZ)
2022                                         ift->prefered_lft = prefered_lft + (jiffies - ift->tstamp) / HZ;
2023                                 spin_unlock(&ift->lock);
2024                                 if (!(flags&IFA_F_TENTATIVE))
2025                                         ipv6_ifa_notify(0, ift);
2026                         }
2027
2028                         if ((create || list_empty(&in6_dev->tempaddr_list)) && in6_dev->cnf.use_tempaddr > 0) {
2029                                 /*
2030                                  * When a new public address is created as described in [ADDRCONF],
2031                                  * also create a new temporary address. Also create a temporary
2032                                  * address if it's enabled but no temporary address currently exists.
2033                                  */
2034                                 read_unlock_bh(&in6_dev->lock);
2035                                 ipv6_create_tempaddr(ifp, NULL);
2036                         } else {
2037                                 read_unlock_bh(&in6_dev->lock);
2038                         }
2039 #endif
2040                         in6_ifa_put(ifp);
2041                         addrconf_verify(0);
2042                 }
2043         }
2044         inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2045         in6_dev_put(in6_dev);
2046 }
2047
2048 /*
2049  *      Set destination address.
2050  *      Special case for SIT interfaces where we create a new "virtual"
2051  *      device.
2052  */
2053 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2054 {
2055         struct in6_ifreq ireq;
2056         struct net_device *dev;
2057         int err = -EINVAL;
2058
2059         rtnl_lock();
2060
2061         err = -EFAULT;
2062         if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2063                 goto err_exit;
2064
2065         dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2066
2067         err = -ENODEV;
2068         if (dev == NULL)
2069                 goto err_exit;
2070
2071 #if defined(CONFIG_IPV6_SIT) || defined(CONFIG_IPV6_SIT_MODULE)
2072         if (dev->type == ARPHRD_SIT) {
2073                 const struct net_device_ops *ops = dev->netdev_ops;
2074                 struct ifreq ifr;
2075                 struct ip_tunnel_parm p;
2076
2077                 err = -EADDRNOTAVAIL;
2078                 if (!(ipv6_addr_type(&ireq.ifr6_addr) & IPV6_ADDR_COMPATv4))
2079                         goto err_exit;
2080
2081                 memset(&p, 0, sizeof(p));
2082                 p.iph.daddr = ireq.ifr6_addr.s6_addr32[3];
2083                 p.iph.saddr = 0;
2084                 p.iph.version = 4;
2085                 p.iph.ihl = 5;
2086                 p.iph.protocol = IPPROTO_IPV6;
2087                 p.iph.ttl = 64;
2088                 ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
2089
2090                 if (ops->ndo_do_ioctl) {
2091                         mm_segment_t oldfs = get_fs();
2092
2093                         set_fs(KERNEL_DS);
2094                         err = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
2095                         set_fs(oldfs);
2096                 } else
2097                         err = -EOPNOTSUPP;
2098
2099                 if (err == 0) {
2100                         err = -ENOBUFS;
2101                         dev = __dev_get_by_name(net, p.name);
2102                         if (!dev)
2103                                 goto err_exit;
2104                         err = dev_open(dev);
2105                 }
2106         }
2107 #endif
2108
2109 err_exit:
2110         rtnl_unlock();
2111         return err;
2112 }
2113
2114 /*
2115  *      Manual configuration of address on an interface
2116  */
2117 static int inet6_addr_add(struct net *net, int ifindex, struct in6_addr *pfx,
2118                           unsigned int plen, __u8 ifa_flags, __u32 prefered_lft,
2119                           __u32 valid_lft)
2120 {
2121         struct inet6_ifaddr *ifp;
2122         struct inet6_dev *idev;
2123         struct net_device *dev;
2124         int scope;
2125         u32 flags;
2126         clock_t expires;
2127         unsigned long timeout;
2128
2129         ASSERT_RTNL();
2130
2131         if (plen > 128)
2132                 return -EINVAL;
2133
2134         /* check the lifetime */
2135         if (!valid_lft || prefered_lft > valid_lft)
2136                 return -EINVAL;
2137
2138         dev = __dev_get_by_index(net, ifindex);
2139         if (!dev)
2140                 return -ENODEV;
2141
2142         idev = addrconf_add_dev(dev);
2143         if (IS_ERR(idev))
2144                 return PTR_ERR(idev);
2145
2146         scope = ipv6_addr_scope(pfx);
2147
2148         timeout = addrconf_timeout_fixup(valid_lft, HZ);
2149         if (addrconf_finite_timeout(timeout)) {
2150                 expires = jiffies_to_clock_t(timeout * HZ);
2151                 valid_lft = timeout;
2152                 flags = RTF_EXPIRES;
2153         } else {
2154                 expires = 0;
2155                 flags = 0;
2156                 ifa_flags |= IFA_F_PERMANENT;
2157         }
2158
2159         timeout = addrconf_timeout_fixup(prefered_lft, HZ);
2160         if (addrconf_finite_timeout(timeout)) {
2161                 if (timeout == 0)
2162                         ifa_flags |= IFA_F_DEPRECATED;
2163                 prefered_lft = timeout;
2164         }
2165
2166         ifp = ipv6_add_addr(idev, pfx, plen, scope, ifa_flags);
2167
2168         if (!IS_ERR(ifp)) {
2169                 spin_lock_bh(&ifp->lock);
2170                 ifp->valid_lft = valid_lft;
2171                 ifp->prefered_lft = prefered_lft;
2172                 ifp->tstamp = jiffies;
2173                 spin_unlock_bh(&ifp->lock);
2174
2175                 addrconf_prefix_route(&ifp->addr, ifp->prefix_len, dev,
2176                                       expires, flags);
2177                 /*
2178                  * Note that section 3.1 of RFC 4429 indicates
2179                  * that the Optimistic flag should not be set for
2180                  * manually configured addresses
2181                  */
2182                 addrconf_dad_start(ifp, 0);
2183                 in6_ifa_put(ifp);
2184                 addrconf_verify(0);
2185                 return 0;
2186         }
2187
2188         return PTR_ERR(ifp);
2189 }
2190
2191 static int inet6_addr_del(struct net *net, int ifindex, struct in6_addr *pfx,
2192                           unsigned int plen)
2193 {
2194         struct inet6_ifaddr *ifp;
2195         struct inet6_dev *idev;
2196         struct net_device *dev;
2197
2198         if (plen > 128)
2199                 return -EINVAL;
2200
2201         dev = __dev_get_by_index(net, ifindex);
2202         if (!dev)
2203                 return -ENODEV;
2204
2205         if ((idev = __in6_dev_get(dev)) == NULL)
2206                 return -ENXIO;
2207
2208         read_lock_bh(&idev->lock);
2209         list_for_each_entry(ifp, &idev->addr_list, if_list) {
2210                 if (ifp->prefix_len == plen &&
2211                     ipv6_addr_equal(pfx, &ifp->addr)) {
2212                         in6_ifa_hold(ifp);
2213                         read_unlock_bh(&idev->lock);
2214
2215                         ipv6_del_addr(ifp);
2216
2217                         /* If the last address is deleted administratively,
2218                            disable IPv6 on this interface.
2219                          */
2220                         if (list_empty(&idev->addr_list))
2221                                 addrconf_ifdown(idev->dev, 1);
2222                         return 0;
2223                 }
2224         }
2225         read_unlock_bh(&idev->lock);
2226         return -EADDRNOTAVAIL;
2227 }
2228
2229
2230 int addrconf_add_ifaddr(struct net *net, void __user *arg)
2231 {
2232         struct in6_ifreq ireq;
2233         int err;
2234
2235         if (!capable(CAP_NET_ADMIN))
2236                 return -EPERM;
2237
2238         if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2239                 return -EFAULT;
2240
2241         rtnl_lock();
2242         err = inet6_addr_add(net, ireq.ifr6_ifindex, &ireq.ifr6_addr,
2243                              ireq.ifr6_prefixlen, IFA_F_PERMANENT,
2244                              INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
2245         rtnl_unlock();
2246         return err;
2247 }
2248
2249 int addrconf_del_ifaddr(struct net *net, void __user *arg)
2250 {
2251         struct in6_ifreq ireq;
2252         int err;
2253
2254         if (!capable(CAP_NET_ADMIN))
2255                 return -EPERM;
2256
2257         if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2258                 return -EFAULT;
2259
2260         rtnl_lock();
2261         err = inet6_addr_del(net, ireq.ifr6_ifindex, &ireq.ifr6_addr,
2262                              ireq.ifr6_prefixlen);
2263         rtnl_unlock();
2264         return err;
2265 }
2266
2267 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
2268                      int plen, int scope)
2269 {
2270         struct inet6_ifaddr *ifp;
2271
2272         ifp = ipv6_add_addr(idev, addr, plen, scope, IFA_F_PERMANENT);
2273         if (!IS_ERR(ifp)) {
2274                 spin_lock_bh(&ifp->lock);
2275                 ifp->flags &= ~IFA_F_TENTATIVE;
2276                 spin_unlock_bh(&ifp->lock);
2277                 ipv6_ifa_notify(RTM_NEWADDR, ifp);
2278                 in6_ifa_put(ifp);
2279         }
2280 }
2281
2282 #if defined(CONFIG_IPV6_SIT) || defined(CONFIG_IPV6_SIT_MODULE)
2283 static void sit_add_v4_addrs(struct inet6_dev *idev)
2284 {
2285         struct in6_addr addr;
2286         struct net_device *dev;
2287         struct net *net = dev_net(idev->dev);
2288         int scope;
2289
2290         ASSERT_RTNL();
2291
2292         memset(&addr, 0, sizeof(struct in6_addr));
2293         memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
2294
2295         if (idev->dev->flags&IFF_POINTOPOINT) {
2296                 addr.s6_addr32[0] = htonl(0xfe800000);
2297                 scope = IFA_LINK;
2298         } else {
2299                 scope = IPV6_ADDR_COMPATv4;
2300         }
2301
2302         if (addr.s6_addr32[3]) {
2303                 add_addr(idev, &addr, 128, scope);
2304                 return;
2305         }
2306
2307         for_each_netdev(net, dev) {
2308                 struct in_device * in_dev = __in_dev_get_rtnl(dev);
2309                 if (in_dev && (dev->flags & IFF_UP)) {
2310                         struct in_ifaddr * ifa;
2311
2312                         int flag = scope;
2313
2314                         for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
2315                                 int plen;
2316
2317                                 addr.s6_addr32[3] = ifa->ifa_local;
2318
2319                                 if (ifa->ifa_scope == RT_SCOPE_LINK)
2320                                         continue;
2321                                 if (ifa->ifa_scope >= RT_SCOPE_HOST) {
2322                                         if (idev->dev->flags&IFF_POINTOPOINT)
2323                                                 continue;
2324                                         flag |= IFA_HOST;
2325                                 }
2326                                 if (idev->dev->flags&IFF_POINTOPOINT)
2327                                         plen = 64;
2328                                 else
2329                                         plen = 96;
2330
2331                                 add_addr(idev, &addr, plen, flag);
2332                         }
2333                 }
2334         }
2335 }
2336 #endif
2337
2338 static void init_loopback(struct net_device *dev)
2339 {
2340         struct inet6_dev  *idev;
2341
2342         /* ::1 */
2343
2344         ASSERT_RTNL();
2345
2346         if ((idev = ipv6_find_idev(dev)) == NULL) {
2347                 printk(KERN_DEBUG "init loopback: add_dev failed\n");
2348                 return;
2349         }
2350
2351         add_addr(idev, &in6addr_loopback, 128, IFA_HOST);
2352 }
2353
2354 static void addrconf_add_linklocal(struct inet6_dev *idev, struct in6_addr *addr)
2355 {
2356         struct inet6_ifaddr * ifp;
2357         u32 addr_flags = IFA_F_PERMANENT;
2358
2359 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2360         if (idev->cnf.optimistic_dad &&
2361             !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
2362                 addr_flags |= IFA_F_OPTIMISTIC;
2363 #endif
2364
2365
2366         ifp = ipv6_add_addr(idev, addr, 64, IFA_LINK, addr_flags);
2367         if (!IS_ERR(ifp)) {
2368                 addrconf_prefix_route(&ifp->addr, ifp->prefix_len, idev->dev, 0, 0);
2369                 addrconf_dad_start(ifp, 0);
2370                 in6_ifa_put(ifp);
2371         }
2372 }
2373
2374 static void addrconf_dev_config(struct net_device *dev)
2375 {
2376         struct in6_addr addr;
2377         struct inet6_dev    * idev;
2378
2379         ASSERT_RTNL();
2380
2381         if ((dev->type != ARPHRD_ETHER) &&
2382             (dev->type != ARPHRD_FDDI) &&
2383             (dev->type != ARPHRD_IEEE802_TR) &&
2384             (dev->type != ARPHRD_ARCNET) &&
2385             (dev->type != ARPHRD_INFINIBAND)) {
2386                 /* Alas, we support only Ethernet autoconfiguration. */
2387                 return;
2388         }
2389
2390         idev = addrconf_add_dev(dev);
2391         if (IS_ERR(idev))
2392                 return;
2393
2394         memset(&addr, 0, sizeof(struct in6_addr));
2395         addr.s6_addr32[0] = htonl(0xFE800000);
2396
2397         if (ipv6_generate_eui64(addr.s6_addr + 8, dev) == 0)
2398                 addrconf_add_linklocal(idev, &addr);
2399 }
2400
2401 #if defined(CONFIG_IPV6_SIT) || defined(CONFIG_IPV6_SIT_MODULE)
2402 static void addrconf_sit_config(struct net_device *dev)
2403 {
2404         struct inet6_dev *idev;
2405
2406         ASSERT_RTNL();
2407
2408         /*
2409          * Configure the tunnel with one of our IPv4
2410          * addresses... we should configure all of
2411          * our v4 addrs in the tunnel
2412          */
2413
2414         if ((idev = ipv6_find_idev(dev)) == NULL) {
2415                 printk(KERN_DEBUG "init sit: add_dev failed\n");
2416                 return;
2417         }
2418
2419         if (dev->priv_flags & IFF_ISATAP) {
2420                 struct in6_addr addr;
2421
2422                 ipv6_addr_set(&addr,  htonl(0xFE800000), 0, 0, 0);
2423                 addrconf_prefix_route(&addr, 64, dev, 0, 0);
2424                 if (!ipv6_generate_eui64(addr.s6_addr + 8, dev))
2425                         addrconf_add_linklocal(idev, &addr);
2426                 return;
2427         }
2428
2429         sit_add_v4_addrs(idev);
2430
2431         if (dev->flags&IFF_POINTOPOINT) {
2432                 addrconf_add_mroute(dev);
2433                 addrconf_add_lroute(dev);
2434         } else
2435                 sit_route_add(dev);
2436 }
2437 #endif
2438
2439 static inline int
2440 ipv6_inherit_linklocal(struct inet6_dev *idev, struct net_device *link_dev)
2441 {
2442         struct in6_addr lladdr;
2443
2444         if (!ipv6_get_lladdr(link_dev, &lladdr, IFA_F_TENTATIVE)) {
2445                 addrconf_add_linklocal(idev, &lladdr);
2446                 return 0;
2447         }
2448         return -1;
2449 }
2450
2451 static void ip6_tnl_add_linklocal(struct inet6_dev *idev)
2452 {
2453         struct net_device *link_dev;
2454         struct net *net = dev_net(idev->dev);
2455
2456         /* first try to inherit the link-local address from the link device */
2457         if (idev->dev->iflink &&
2458             (link_dev = __dev_get_by_index(net, idev->dev->iflink))) {
2459                 if (!ipv6_inherit_linklocal(idev, link_dev))
2460                         return;
2461         }
2462         /* then try to inherit it from any device */
2463         for_each_netdev(net, link_dev) {
2464                 if (!ipv6_inherit_linklocal(idev, link_dev))
2465                         return;
2466         }
2467         printk(KERN_DEBUG "init ip6-ip6: add_linklocal failed\n");
2468 }
2469
2470 /*
2471  * Autoconfigure tunnel with a link-local address so routing protocols,
2472  * DHCPv6, MLD etc. can be run over the virtual link
2473  */
2474
2475 static void addrconf_ip6_tnl_config(struct net_device *dev)
2476 {
2477         struct inet6_dev *idev;
2478
2479         ASSERT_RTNL();
2480
2481         idev = addrconf_add_dev(dev);
2482         if (IS_ERR(idev)) {
2483                 printk(KERN_DEBUG "init ip6-ip6: add_dev failed\n");
2484                 return;
2485         }
2486         ip6_tnl_add_linklocal(idev);
2487 }
2488
2489 static int addrconf_notify(struct notifier_block *this, unsigned long event,
2490                            void * data)
2491 {
2492         struct net_device *dev = (struct net_device *) data;
2493         struct inet6_dev *idev = __in6_dev_get(dev);
2494         int run_pending = 0;
2495         int err;
2496
2497         switch (event) {
2498         case NETDEV_REGISTER:
2499                 if (!idev && dev->mtu >= IPV6_MIN_MTU) {
2500                         idev = ipv6_add_dev(dev);
2501                         if (!idev)
2502                                 return notifier_from_errno(-ENOMEM);
2503                 }
2504                 break;
2505
2506         case NETDEV_UP:
2507         case NETDEV_CHANGE:
2508                 if (dev->flags & IFF_SLAVE)
2509                         break;
2510
2511                 if (event == NETDEV_UP) {
2512                         if (!addrconf_qdisc_ok(dev)) {
2513                                 /* device is not ready yet. */
2514                                 printk(KERN_INFO
2515                                         "ADDRCONF(NETDEV_UP): %s: "
2516                                         "link is not ready\n",
2517                                         dev->name);
2518                                 break;
2519                         }
2520
2521                         if (!idev && dev->mtu >= IPV6_MIN_MTU)
2522                                 idev = ipv6_add_dev(dev);
2523
2524                         if (idev) {
2525                                 idev->if_flags |= IF_READY;
2526                                 run_pending = 1;
2527                         }
2528                 } else {
2529                         if (!addrconf_qdisc_ok(dev)) {
2530                                 /* device is still not ready. */
2531                                 break;
2532                         }
2533
2534                         if (idev) {
2535                                 if (idev->if_flags & IF_READY)
2536                                         /* device is already configured. */
2537                                         break;
2538                                 idev->if_flags |= IF_READY;
2539                         }
2540
2541                         printk(KERN_INFO
2542                                         "ADDRCONF(NETDEV_CHANGE): %s: "
2543                                         "link becomes ready\n",
2544                                         dev->name);
2545
2546                         run_pending = 1;
2547                 }
2548
2549                 switch (dev->type) {
2550 #if defined(CONFIG_IPV6_SIT) || defined(CONFIG_IPV6_SIT_MODULE)
2551                 case ARPHRD_SIT:
2552                         addrconf_sit_config(dev);
2553                         break;
2554 #endif
2555                 case ARPHRD_TUNNEL6:
2556                         addrconf_ip6_tnl_config(dev);
2557                         break;
2558                 case ARPHRD_LOOPBACK:
2559                         init_loopback(dev);
2560                         break;
2561
2562                 default:
2563                         addrconf_dev_config(dev);
2564                         break;
2565                 }
2566
2567                 if (idev) {
2568                         if (run_pending)
2569                                 addrconf_dad_run(idev);
2570
2571                         /*
2572                          * If the MTU changed during the interface down,
2573                          * when the interface up, the changed MTU must be
2574                          * reflected in the idev as well as routers.
2575                          */
2576                         if (idev->cnf.mtu6 != dev->mtu &&
2577                             dev->mtu >= IPV6_MIN_MTU) {
2578                                 rt6_mtu_change(dev, dev->mtu);
2579                                 idev->cnf.mtu6 = dev->mtu;
2580                         }
2581                         idev->tstamp = jiffies;
2582                         inet6_ifinfo_notify(RTM_NEWLINK, idev);
2583
2584                         /*
2585                          * If the changed mtu during down is lower than
2586                          * IPV6_MIN_MTU stop IPv6 on this interface.
2587                          */
2588                         if (dev->mtu < IPV6_MIN_MTU)
2589                                 addrconf_ifdown(dev, 1);
2590                 }
2591                 break;
2592
2593         case NETDEV_CHANGEMTU:
2594                 if (idev && dev->mtu >= IPV6_MIN_MTU) {
2595                         rt6_mtu_change(dev, dev->mtu);
2596                         idev->cnf.mtu6 = dev->mtu;
2597                         break;
2598                 }
2599
2600                 if (!idev && dev->mtu >= IPV6_MIN_MTU) {
2601                         idev = ipv6_add_dev(dev);
2602                         if (idev)
2603                                 break;
2604                 }
2605
2606                 /*
2607                  * MTU falled under IPV6_MIN_MTU.
2608                  * Stop IPv6 on this interface.
2609                  */
2610
2611         case NETDEV_DOWN:
2612         case NETDEV_UNREGISTER:
2613                 /*
2614                  *      Remove all addresses from this interface.
2615                  */
2616                 addrconf_ifdown(dev, event != NETDEV_DOWN);
2617                 break;
2618
2619         case NETDEV_CHANGENAME:
2620                 if (idev) {
2621                         snmp6_unregister_dev(idev);
2622                         addrconf_sysctl_unregister(idev);
2623                         addrconf_sysctl_register(idev);
2624                         err = snmp6_register_dev(idev);
2625                         if (err)
2626                                 return notifier_from_errno(err);
2627                 }
2628                 break;
2629
2630         case NETDEV_PRE_TYPE_CHANGE:
2631         case NETDEV_POST_TYPE_CHANGE:
2632                 addrconf_type_change(dev, event);
2633                 break;
2634         }
2635
2636         return NOTIFY_OK;
2637 }
2638
2639 /*
2640  *      addrconf module should be notified of a device going up
2641  */
2642 static struct notifier_block ipv6_dev_notf = {
2643         .notifier_call = addrconf_notify,
2644 };
2645
2646 static void addrconf_type_change(struct net_device *dev, unsigned long event)
2647 {
2648         struct inet6_dev *idev;
2649         ASSERT_RTNL();
2650
2651         idev = __in6_dev_get(dev);
2652
2653         if (event == NETDEV_POST_TYPE_CHANGE)
2654                 ipv6_mc_remap(idev);
2655         else if (event == NETDEV_PRE_TYPE_CHANGE)
2656                 ipv6_mc_unmap(idev);
2657 }
2658
2659 static int addrconf_ifdown(struct net_device *dev, int how)
2660 {
2661         struct net *net = dev_net(dev);
2662         struct inet6_dev *idev;
2663         struct inet6_ifaddr *ifa;
2664         int state, i;
2665
2666         ASSERT_RTNL();
2667
2668         rt6_ifdown(net, dev);
2669         neigh_ifdown(&nd_tbl, dev);
2670
2671         idev = __in6_dev_get(dev);
2672         if (idev == NULL)
2673                 return -ENODEV;
2674
2675         /*
2676          * Step 1: remove reference to ipv6 device from parent device.
2677          *         Do not dev_put!
2678          */
2679         if (how) {
2680                 idev->dead = 1;
2681
2682                 /* protected by rtnl_lock */
2683                 rcu_assign_pointer(dev->ip6_ptr, NULL);
2684
2685                 /* Step 1.5: remove snmp6 entry */
2686                 snmp6_unregister_dev(idev);
2687
2688         }
2689
2690         /* Step 2: clear hash table */
2691         for (i = 0; i < IN6_ADDR_HSIZE; i++) {
2692                 struct hlist_head *h = &inet6_addr_lst[i];
2693                 struct hlist_node *n;
2694
2695                 spin_lock_bh(&addrconf_hash_lock);
2696         restart:
2697                 hlist_for_each_entry_rcu(ifa, n, h, addr_lst) {
2698                         if (ifa->idev == idev) {
2699                                 hlist_del_init_rcu(&ifa->addr_lst);
2700                                 addrconf_del_timer(ifa);
2701                                 goto restart;
2702                         }
2703                 }
2704                 spin_unlock_bh(&addrconf_hash_lock);
2705         }
2706
2707         write_lock_bh(&idev->lock);
2708
2709         /* Step 2: clear flags for stateless addrconf */
2710         if (!how)
2711                 idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
2712
2713 #ifdef CONFIG_IPV6_PRIVACY
2714         if (how && del_timer(&idev->regen_timer))
2715                 in6_dev_put(idev);
2716
2717         /* Step 3: clear tempaddr list */
2718         while (!list_empty(&idev->tempaddr_list)) {
2719                 ifa = list_first_entry(&idev->tempaddr_list,
2720                                        struct inet6_ifaddr, tmp_list);
2721                 list_del(&ifa->tmp_list);
2722                 write_unlock_bh(&idev->lock);
2723                 spin_lock_bh(&ifa->lock);
2724
2725                 if (ifa->ifpub) {
2726                         in6_ifa_put(ifa->ifpub);
2727                         ifa->ifpub = NULL;
2728                 }
2729                 spin_unlock_bh(&ifa->lock);
2730                 in6_ifa_put(ifa);
2731                 write_lock_bh(&idev->lock);
2732         }
2733 #endif
2734
2735         while (!list_empty(&idev->addr_list)) {
2736                 ifa = list_first_entry(&idev->addr_list,
2737                                        struct inet6_ifaddr, if_list);
2738                 addrconf_del_timer(ifa);
2739
2740                 list_del(&ifa->if_list);
2741
2742                 write_unlock_bh(&idev->lock);
2743
2744                 spin_lock_bh(&ifa->state_lock);
2745                 state = ifa->state;
2746                 ifa->state = INET6_IFADDR_STATE_DEAD;
2747                 spin_unlock_bh(&ifa->state_lock);
2748
2749                 if (state != INET6_IFADDR_STATE_DEAD) {
2750                         __ipv6_ifa_notify(RTM_DELADDR, ifa);
2751                         atomic_notifier_call_chain(&inet6addr_chain, NETDEV_DOWN, ifa);
2752                 }
2753                 in6_ifa_put(ifa);
2754
2755                 write_lock_bh(&idev->lock);
2756         }
2757
2758         write_unlock_bh(&idev->lock);
2759
2760         /* Step 5: Discard multicast list */
2761         if (how)
2762                 ipv6_mc_destroy_dev(idev);
2763         else
2764                 ipv6_mc_down(idev);
2765
2766         idev->tstamp = jiffies;
2767
2768         /* Last: Shot the device (if unregistered) */
2769         if (how) {
2770                 addrconf_sysctl_unregister(idev);
2771                 neigh_parms_release(&nd_tbl, idev->nd_parms);
2772                 neigh_ifdown(&nd_tbl, dev);
2773                 in6_dev_put(idev);
2774         }
2775         return 0;
2776 }
2777
2778 static void addrconf_rs_timer(unsigned long data)
2779 {
2780         struct inet6_ifaddr *ifp = (struct inet6_ifaddr *) data;
2781         struct inet6_dev *idev = ifp->idev;
2782
2783         read_lock(&idev->lock);
2784         if (idev->dead || !(idev->if_flags & IF_READY))
2785                 goto out;
2786
2787         if (idev->cnf.forwarding)
2788                 goto out;
2789
2790         /* Announcement received after solicitation was sent */
2791         if (idev->if_flags & IF_RA_RCVD)
2792                 goto out;
2793
2794         spin_lock(&ifp->lock);
2795         if (ifp->probes++ < idev->cnf.rtr_solicits) {
2796                 /* The wait after the last probe can be shorter */
2797                 addrconf_mod_timer(ifp, AC_RS,
2798                                    (ifp->probes == idev->cnf.rtr_solicits) ?
2799                                    idev->cnf.rtr_solicit_delay :
2800                                    idev->cnf.rtr_solicit_interval);
2801                 spin_unlock(&ifp->lock);
2802
2803                 ndisc_send_rs(idev->dev, &ifp->addr, &in6addr_linklocal_allrouters);
2804         } else {
2805                 spin_unlock(&ifp->lock);
2806                 /*
2807                  * Note: we do not support deprecated "all on-link"
2808                  * assumption any longer.
2809                  */
2810                 printk(KERN_DEBUG "%s: no IPv6 routers present\n",
2811                        idev->dev->name);
2812         }
2813
2814 out:
2815         read_unlock(&idev->lock);
2816         in6_ifa_put(ifp);
2817 }
2818
2819 /*
2820  *      Duplicate Address Detection
2821  */
2822 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
2823 {
2824         unsigned long rand_num;
2825         struct inet6_dev *idev = ifp->idev;
2826
2827         if (ifp->flags & IFA_F_OPTIMISTIC)
2828                 rand_num = 0;
2829         else
2830                 rand_num = net_random() % (idev->cnf.rtr_solicit_delay ? : 1);
2831
2832         ifp->probes = idev->cnf.dad_transmits;
2833         addrconf_mod_timer(ifp, AC_DAD, rand_num);
2834 }
2835
2836 static void addrconf_dad_start(struct inet6_ifaddr *ifp, u32 flags)
2837 {
2838         struct inet6_dev *idev = ifp->idev;
2839         struct net_device *dev = idev->dev;
2840
2841         addrconf_join_solict(dev, &ifp->addr);
2842
2843         net_srandom(ifp->addr.s6_addr32[3]);
2844
2845         read_lock_bh(&idev->lock);
2846         spin_lock(&ifp->lock);
2847         if (ifp->state == INET6_IFADDR_STATE_DEAD)
2848                 goto out;
2849
2850         if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
2851             idev->cnf.accept_dad < 1 ||
2852             !(ifp->flags&IFA_F_TENTATIVE) ||
2853             ifp->flags & IFA_F_NODAD) {
2854                 ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
2855                 spin_unlock(&ifp->lock);
2856                 read_unlock_bh(&idev->lock);
2857
2858                 addrconf_dad_completed(ifp);
2859                 return;
2860         }
2861
2862         if (!(idev->if_flags & IF_READY)) {
2863                 spin_unlock(&ifp->lock);
2864                 read_unlock_bh(&idev->lock);
2865                 /*
2866                  * If the device is not ready:
2867                  * - keep it tentative if it is a permanent address.
2868                  * - otherwise, kill it.
2869                  */
2870                 in6_ifa_hold(ifp);
2871                 addrconf_dad_stop(ifp, 0);
2872                 return;
2873         }
2874
2875         /*
2876          * Optimistic nodes can start receiving
2877          * Frames right away
2878          */
2879         if (ifp->flags & IFA_F_OPTIMISTIC)
2880                 ip6_ins_rt(ifp->rt);
2881
2882         addrconf_dad_kick(ifp);
2883 out:
2884         spin_unlock(&ifp->lock);
2885         read_unlock_bh(&idev->lock);
2886 }
2887
2888 static void addrconf_dad_timer(unsigned long data)
2889 {
2890         struct inet6_ifaddr *ifp = (struct inet6_ifaddr *) data;
2891         struct inet6_dev *idev = ifp->idev;
2892         struct in6_addr mcaddr;
2893
2894         if (!ifp->probes && addrconf_dad_end(ifp))
2895                 goto out;
2896
2897         read_lock(&idev->lock);
2898         if (idev->dead || !(idev->if_flags & IF_READY)) {
2899                 read_unlock(&idev->lock);
2900                 goto out;
2901         }
2902
2903         spin_lock(&ifp->lock);
2904         if (ifp->state == INET6_IFADDR_STATE_DEAD) {
2905                 spin_unlock(&ifp->lock);
2906                 read_unlock(&idev->lock);
2907                 goto out;
2908         }
2909
2910         if (ifp->probes == 0) {
2911                 /*
2912                  * DAD was successful
2913                  */
2914
2915                 ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
2916                 spin_unlock(&ifp->lock);
2917                 read_unlock(&idev->lock);
2918
2919                 addrconf_dad_completed(ifp);
2920
2921                 goto out;
2922         }
2923
2924         ifp->probes--;
2925         addrconf_mod_timer(ifp, AC_DAD, ifp->idev->nd_parms->retrans_time);
2926         spin_unlock(&ifp->lock);
2927         read_unlock(&idev->lock);
2928
2929         /* send a neighbour solicitation for our addr */
2930         addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
2931         ndisc_send_ns(ifp->idev->dev, NULL, &ifp->addr, &mcaddr, &in6addr_any);
2932 out:
2933         in6_ifa_put(ifp);
2934 }
2935
2936 static void addrconf_dad_completed(struct inet6_ifaddr *ifp)
2937 {
2938         struct net_device *dev = ifp->idev->dev;
2939
2940         /*
2941          *      Configure the address for reception. Now it is valid.
2942          */
2943
2944         ipv6_ifa_notify(RTM_NEWADDR, ifp);
2945
2946         /* If added prefix is link local and forwarding is off,
2947            start sending router solicitations.
2948          */
2949
2950         if ((ifp->idev->cnf.forwarding == 0 ||
2951              ifp->idev->cnf.forwarding == 2) &&
2952             ifp->idev->cnf.rtr_solicits > 0 &&
2953             (dev->flags&IFF_LOOPBACK) == 0 &&
2954             (ipv6_addr_type(&ifp->addr) & IPV6_ADDR_LINKLOCAL)) {
2955                 /*
2956                  *      If a host as already performed a random delay
2957                  *      [...] as part of DAD [...] there is no need
2958                  *      to delay again before sending the first RS
2959                  */
2960                 ndisc_send_rs(ifp->idev->dev, &ifp->addr, &in6addr_linklocal_allrouters);
2961
2962                 spin_lock_bh(&ifp->lock);
2963                 ifp->probes = 1;
2964                 ifp->idev->if_flags |= IF_RS_SENT;
2965                 addrconf_mod_timer(ifp, AC_RS, ifp->idev->cnf.rtr_solicit_interval);
2966                 spin_unlock_bh(&ifp->lock);
2967         }
2968 }
2969
2970 static void addrconf_dad_run(struct inet6_dev *idev)
2971 {
2972         struct inet6_ifaddr *ifp;
2973
2974         read_lock_bh(&idev->lock);
2975         list_for_each_entry(ifp, &idev->addr_list, if_list) {
2976                 spin_lock(&ifp->lock);
2977                 if (ifp->flags & IFA_F_TENTATIVE &&
2978                     ifp->state == INET6_IFADDR_STATE_DAD)
2979                         addrconf_dad_kick(ifp);
2980                 spin_unlock(&ifp->lock);
2981         }
2982         read_unlock_bh(&idev->lock);
2983 }
2984
2985 #ifdef CONFIG_PROC_FS
2986 struct if6_iter_state {
2987         struct seq_net_private p;
2988         int bucket;
2989 };
2990
2991 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq)
2992 {
2993         struct inet6_ifaddr *ifa = NULL;
2994         struct if6_iter_state *state = seq->private;
2995         struct net *net = seq_file_net(seq);
2996
2997         for (state->bucket = 0; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
2998                 struct hlist_node *n;
2999                 hlist_for_each_entry_rcu_bh(ifa, n, &inet6_addr_lst[state->bucket],
3000                                          addr_lst)
3001                         if (net_eq(dev_net(ifa->idev->dev), net))
3002                                 return ifa;
3003         }
3004         return NULL;
3005 }
3006
3007 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
3008                                          struct inet6_ifaddr *ifa)
3009 {
3010         struct if6_iter_state *state = seq->private;
3011         struct net *net = seq_file_net(seq);
3012         struct hlist_node *n = &ifa->addr_lst;
3013
3014         hlist_for_each_entry_continue_rcu_bh(ifa, n, addr_lst)
3015                 if (net_eq(dev_net(ifa->idev->dev), net))
3016                         return ifa;
3017
3018         while (++state->bucket < IN6_ADDR_HSIZE) {
3019                 hlist_for_each_entry_rcu_bh(ifa, n,
3020                                      &inet6_addr_lst[state->bucket], addr_lst) {
3021                         if (net_eq(dev_net(ifa->idev->dev), net))
3022                                 return ifa;
3023                 }
3024         }
3025
3026         return NULL;
3027 }
3028
3029 static struct inet6_ifaddr *if6_get_idx(struct seq_file *seq, loff_t pos)
3030 {
3031         struct inet6_ifaddr *ifa = if6_get_first(seq);
3032
3033         if (ifa)
3034                 while (pos && (ifa = if6_get_next(seq, ifa)) != NULL)
3035                         --pos;
3036         return pos ? NULL : ifa;
3037 }
3038
3039 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
3040         __acquires(rcu_bh)
3041 {
3042         rcu_read_lock_bh();
3043         return if6_get_idx(seq, *pos);
3044 }
3045
3046 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3047 {
3048         struct inet6_ifaddr *ifa;
3049
3050         ifa = if6_get_next(seq, v);
3051         ++*pos;
3052         return ifa;
3053 }
3054
3055 static void if6_seq_stop(struct seq_file *seq, void *v)
3056         __releases(rcu_bh)
3057 {
3058         rcu_read_unlock_bh();
3059 }
3060
3061 static int if6_seq_show(struct seq_file *seq, void *v)
3062 {
3063         struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
3064         seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
3065                    &ifp->addr,
3066                    ifp->idev->dev->ifindex,
3067                    ifp->prefix_len,
3068                    ifp->scope,
3069                    ifp->flags,
3070                    ifp->idev->dev->name);
3071         return 0;
3072 }
3073
3074 static const struct seq_operations if6_seq_ops = {
3075         .start  = if6_seq_start,
3076         .next   = if6_seq_next,
3077         .show   = if6_seq_show,
3078         .stop   = if6_seq_stop,
3079 };
3080
3081 static int if6_seq_open(struct inode *inode, struct file *file)
3082 {
3083         return seq_open_net(inode, file, &if6_seq_ops,
3084                             sizeof(struct if6_iter_state));
3085 }
3086
3087 static const struct file_operations if6_fops = {
3088         .owner          = THIS_MODULE,
3089         .open           = if6_seq_open,
3090         .read           = seq_read,
3091         .llseek         = seq_lseek,
3092         .release        = seq_release_net,
3093 };
3094
3095 static int __net_init if6_proc_net_init(struct net *net)
3096 {
3097         if (!proc_net_fops_create(net, "if_inet6", S_IRUGO, &if6_fops))
3098                 return -ENOMEM;
3099         return 0;
3100 }
3101
3102 static void __net_exit if6_proc_net_exit(struct net *net)
3103 {
3104        proc_net_remove(net, "if_inet6");
3105 }
3106
3107 static struct pernet_operations if6_proc_net_ops = {
3108        .init = if6_proc_net_init,
3109        .exit = if6_proc_net_exit,
3110 };
3111
3112 int __init if6_proc_init(void)
3113 {
3114         return register_pernet_subsys(&if6_proc_net_ops);
3115 }
3116
3117 void if6_proc_exit(void)
3118 {
3119         unregister_pernet_subsys(&if6_proc_net_ops);
3120 }
3121 #endif  /* CONFIG_PROC_FS */
3122
3123 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
3124 /* Check if address is a home address configured on any interface. */
3125 int ipv6_chk_home_addr(struct net *net, struct in6_addr *addr)
3126 {
3127         int ret = 0;
3128         struct inet6_ifaddr *ifp = NULL;
3129         struct hlist_node *n;
3130         unsigned int hash = ipv6_addr_hash(addr);
3131
3132         rcu_read_lock_bh();
3133         hlist_for_each_entry_rcu_bh(ifp, n, &inet6_addr_lst[hash], addr_lst) {
3134                 if (!net_eq(dev_net(ifp->idev->dev), net))
3135                         continue;
3136                 if (ipv6_addr_equal(&ifp->addr, addr) &&
3137                     (ifp->flags & IFA_F_HOMEADDRESS)) {
3138                         ret = 1;
3139                         break;
3140                 }
3141         }
3142         rcu_read_unlock_bh();
3143         return ret;
3144 }
3145 #endif
3146
3147 /*
3148  *      Periodic address status verification
3149  */
3150
3151 static void addrconf_verify(unsigned long foo)
3152 {
3153         unsigned long now, next, next_sec, next_sched;
3154         struct inet6_ifaddr *ifp;
3155         struct hlist_node *node;
3156         int i;
3157
3158         rcu_read_lock_bh();
3159