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TOMOYO Linux Cross Reference
Linux/net/ipv6/addrconf.c

Version: ~ [ linux-5.15-rc5 ] ~ [ linux-5.14.11 ] ~ [ linux-5.13.19 ] ~ [ linux-5.12.19 ] ~ [ linux-5.11.22 ] ~ [ linux-5.10.72 ] ~ [ linux-5.9.16 ] ~ [ linux-5.8.18 ] ~ [ linux-5.7.19 ] ~ [ linux-5.6.19 ] ~ [ linux-5.5.19 ] ~ [ linux-5.4.152 ] ~ [ linux-5.3.18 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.210 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.250 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.286 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.288 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.18.140 ] ~ [ linux-3.16.85 ] ~ [ linux-3.14.79 ] ~ [ linux-3.12.74 ] ~ [ linux-3.10.108 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
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  1 /*
  2  *      IPv6 Address [auto]configuration
  3  *      Linux INET6 implementation
  4  *
  5  *      Authors:
  6  *      Pedro Roque             <roque@di.fc.ul.pt>
  7  *      Alexey Kuznetsov        <kuznet@ms2.inr.ac.ru>
  8  *
  9  *      This program is free software; you can redistribute it and/or
 10  *      modify it under the terms of the GNU General Public License
 11  *      as published by the Free Software Foundation; either version
 12  *      2 of the License, or (at your option) any later version.
 13  */
 14 
 15 /*
 16  *      Changes:
 17  *
 18  *      Janos Farkas                    :       delete timer on ifdown
 19  *      <chexum@bankinf.banki.hu>
 20  *      Andi Kleen                      :       kill double kfree on module
 21  *                                              unload.
 22  *      Maciej W. Rozycki               :       FDDI support
 23  *      sekiya@USAGI                    :       Don't send too many RS
 24  *                                              packets.
 25  *      yoshfuji@USAGI                  :       Fixed interval between DAD
 26  *                                              packets.
 27  *      YOSHIFUJI Hideaki @USAGI        :       improved accuracy of
 28  *                                              address validation timer.
 29  *      YOSHIFUJI Hideaki @USAGI        :       Privacy Extensions (RFC3041)
 30  *                                              support.
 31  *      Yuji SEKIYA @USAGI              :       Don't assign a same IPv6
 32  *                                              address on a same interface.
 33  *      YOSHIFUJI Hideaki @USAGI        :       ARCnet support
 34  *      YOSHIFUJI Hideaki @USAGI        :       convert /proc/net/if_inet6 to
 35  *                                              seq_file.
 36  *      YOSHIFUJI Hideaki @USAGI        :       improved source address
 37  *                                              selection; consider scope,
 38  *                                              status etc.
 39  */
 40 
 41 #define pr_fmt(fmt) "IPv6: " fmt
 42 
 43 #include <linux/errno.h>
 44 #include <linux/types.h>
 45 #include <linux/kernel.h>
 46 #include <linux/sched/signal.h>
 47 #include <linux/socket.h>
 48 #include <linux/sockios.h>
 49 #include <linux/net.h>
 50 #include <linux/inet.h>
 51 #include <linux/in6.h>
 52 #include <linux/netdevice.h>
 53 #include <linux/if_addr.h>
 54 #include <linux/if_arp.h>
 55 #include <linux/if_arcnet.h>
 56 #include <linux/if_infiniband.h>
 57 #include <linux/route.h>
 58 #include <linux/inetdevice.h>
 59 #include <linux/init.h>
 60 #include <linux/slab.h>
 61 #ifdef CONFIG_SYSCTL
 62 #include <linux/sysctl.h>
 63 #endif
 64 #include <linux/capability.h>
 65 #include <linux/delay.h>
 66 #include <linux/notifier.h>
 67 #include <linux/string.h>
 68 #include <linux/hash.h>
 69 
 70 #include <net/net_namespace.h>
 71 #include <net/sock.h>
 72 #include <net/snmp.h>
 73 
 74 #include <net/6lowpan.h>
 75 #include <net/firewire.h>
 76 #include <net/ipv6.h>
 77 #include <net/protocol.h>
 78 #include <net/ndisc.h>
 79 #include <net/ip6_route.h>
 80 #include <net/addrconf.h>
 81 #include <net/tcp.h>
 82 #include <net/ip.h>
 83 #include <net/netlink.h>
 84 #include <net/pkt_sched.h>
 85 #include <net/l3mdev.h>
 86 #include <linux/if_tunnel.h>
 87 #include <linux/rtnetlink.h>
 88 #include <linux/netconf.h>
 89 #include <linux/random.h>
 90 #include <linux/uaccess.h>
 91 #include <asm/unaligned.h>
 92 
 93 #include <linux/proc_fs.h>
 94 #include <linux/seq_file.h>
 95 #include <linux/export.h>
 96 
 97 #define INFINITY_LIFE_TIME      0xFFFFFFFF
 98 
 99 #define IPV6_MAX_STRLEN \
100         sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255")
101 
102 static inline u32 cstamp_delta(unsigned long cstamp)
103 {
104         return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
105 }
106 
107 static inline s32 rfc3315_s14_backoff_init(s32 irt)
108 {
109         /* multiply 'initial retransmission time' by 0.9 .. 1.1 */
110         u64 tmp = (900000 + prandom_u32() % 200001) * (u64)irt;
111         do_div(tmp, 1000000);
112         return (s32)tmp;
113 }
114 
115 static inline s32 rfc3315_s14_backoff_update(s32 rt, s32 mrt)
116 {
117         /* multiply 'retransmission timeout' by 1.9 .. 2.1 */
118         u64 tmp = (1900000 + prandom_u32() % 200001) * (u64)rt;
119         do_div(tmp, 1000000);
120         if ((s32)tmp > mrt) {
121                 /* multiply 'maximum retransmission time' by 0.9 .. 1.1 */
122                 tmp = (900000 + prandom_u32() % 200001) * (u64)mrt;
123                 do_div(tmp, 1000000);
124         }
125         return (s32)tmp;
126 }
127 
128 #ifdef CONFIG_SYSCTL
129 static int addrconf_sysctl_register(struct inet6_dev *idev);
130 static void addrconf_sysctl_unregister(struct inet6_dev *idev);
131 #else
132 static inline int addrconf_sysctl_register(struct inet6_dev *idev)
133 {
134         return 0;
135 }
136 
137 static inline void addrconf_sysctl_unregister(struct inet6_dev *idev)
138 {
139 }
140 #endif
141 
142 static void ipv6_regen_rndid(struct inet6_dev *idev);
143 static void ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr);
144 
145 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev);
146 static int ipv6_count_addresses(const struct inet6_dev *idev);
147 static int ipv6_generate_stable_address(struct in6_addr *addr,
148                                         u8 dad_count,
149                                         const struct inet6_dev *idev);
150 
151 #define IN6_ADDR_HSIZE_SHIFT    8
152 #define IN6_ADDR_HSIZE          (1 << IN6_ADDR_HSIZE_SHIFT)
153 /*
154  *      Configured unicast address hash table
155  */
156 static struct hlist_head inet6_addr_lst[IN6_ADDR_HSIZE];
157 static DEFINE_SPINLOCK(addrconf_hash_lock);
158 
159 static void addrconf_verify(void);
160 static void addrconf_verify_rtnl(void);
161 static void addrconf_verify_work(struct work_struct *);
162 
163 static struct workqueue_struct *addrconf_wq;
164 static DECLARE_DELAYED_WORK(addr_chk_work, addrconf_verify_work);
165 
166 static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
167 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
168 
169 static void addrconf_type_change(struct net_device *dev,
170                                  unsigned long event);
171 static int addrconf_ifdown(struct net_device *dev, int how);
172 
173 static struct rt6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
174                                                   int plen,
175                                                   const struct net_device *dev,
176                                                   u32 flags, u32 noflags);
177 
178 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
179 static void addrconf_dad_work(struct work_struct *w);
180 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
181                                    bool send_na);
182 static void addrconf_dad_run(struct inet6_dev *idev);
183 static void addrconf_rs_timer(struct timer_list *t);
184 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
185 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
186 
187 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
188                                 struct prefix_info *pinfo);
189 
190 static struct ipv6_devconf ipv6_devconf __read_mostly = {
191         .forwarding             = 0,
192         .hop_limit              = IPV6_DEFAULT_HOPLIMIT,
193         .mtu6                   = IPV6_MIN_MTU,
194         .accept_ra              = 1,
195         .accept_redirects       = 1,
196         .autoconf               = 1,
197         .force_mld_version      = 0,
198         .mldv1_unsolicited_report_interval = 10 * HZ,
199         .mldv2_unsolicited_report_interval = HZ,
200         .dad_transmits          = 1,
201         .rtr_solicits           = MAX_RTR_SOLICITATIONS,
202         .rtr_solicit_interval   = RTR_SOLICITATION_INTERVAL,
203         .rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
204         .rtr_solicit_delay      = MAX_RTR_SOLICITATION_DELAY,
205         .use_tempaddr           = 0,
206         .temp_valid_lft         = TEMP_VALID_LIFETIME,
207         .temp_prefered_lft      = TEMP_PREFERRED_LIFETIME,
208         .regen_max_retry        = REGEN_MAX_RETRY,
209         .max_desync_factor      = MAX_DESYNC_FACTOR,
210         .max_addresses          = IPV6_MAX_ADDRESSES,
211         .accept_ra_defrtr       = 1,
212         .accept_ra_from_local   = 0,
213         .accept_ra_min_hop_limit= 1,
214         .accept_ra_pinfo        = 1,
215 #ifdef CONFIG_IPV6_ROUTER_PREF
216         .accept_ra_rtr_pref     = 1,
217         .rtr_probe_interval     = 60 * HZ,
218 #ifdef CONFIG_IPV6_ROUTE_INFO
219         .accept_ra_rt_info_min_plen = 0,
220         .accept_ra_rt_info_max_plen = 0,
221 #endif
222 #endif
223         .proxy_ndp              = 0,
224         .accept_source_route    = 0,    /* we do not accept RH0 by default. */
225         .disable_ipv6           = 0,
226         .accept_dad             = 0,
227         .suppress_frag_ndisc    = 1,
228         .accept_ra_mtu          = 1,
229         .stable_secret          = {
230                 .initialized = false,
231         },
232         .use_oif_addrs_only     = 0,
233         .ignore_routes_with_linkdown = 0,
234         .keep_addr_on_down      = 0,
235         .seg6_enabled           = 0,
236 #ifdef CONFIG_IPV6_SEG6_HMAC
237         .seg6_require_hmac      = 0,
238 #endif
239         .enhanced_dad           = 1,
240         .addr_gen_mode          = IN6_ADDR_GEN_MODE_EUI64,
241         .disable_policy         = 0,
242 };
243 
244 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
245         .forwarding             = 0,
246         .hop_limit              = IPV6_DEFAULT_HOPLIMIT,
247         .mtu6                   = IPV6_MIN_MTU,
248         .accept_ra              = 1,
249         .accept_redirects       = 1,
250         .autoconf               = 1,
251         .force_mld_version      = 0,
252         .mldv1_unsolicited_report_interval = 10 * HZ,
253         .mldv2_unsolicited_report_interval = HZ,
254         .dad_transmits          = 1,
255         .rtr_solicits           = MAX_RTR_SOLICITATIONS,
256         .rtr_solicit_interval   = RTR_SOLICITATION_INTERVAL,
257         .rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
258         .rtr_solicit_delay      = MAX_RTR_SOLICITATION_DELAY,
259         .use_tempaddr           = 0,
260         .temp_valid_lft         = TEMP_VALID_LIFETIME,
261         .temp_prefered_lft      = TEMP_PREFERRED_LIFETIME,
262         .regen_max_retry        = REGEN_MAX_RETRY,
263         .max_desync_factor      = MAX_DESYNC_FACTOR,
264         .max_addresses          = IPV6_MAX_ADDRESSES,
265         .accept_ra_defrtr       = 1,
266         .accept_ra_from_local   = 0,
267         .accept_ra_min_hop_limit= 1,
268         .accept_ra_pinfo        = 1,
269 #ifdef CONFIG_IPV6_ROUTER_PREF
270         .accept_ra_rtr_pref     = 1,
271         .rtr_probe_interval     = 60 * HZ,
272 #ifdef CONFIG_IPV6_ROUTE_INFO
273         .accept_ra_rt_info_min_plen = 0,
274         .accept_ra_rt_info_max_plen = 0,
275 #endif
276 #endif
277         .proxy_ndp              = 0,
278         .accept_source_route    = 0,    /* we do not accept RH0 by default. */
279         .disable_ipv6           = 0,
280         .accept_dad             = 1,
281         .suppress_frag_ndisc    = 1,
282         .accept_ra_mtu          = 1,
283         .stable_secret          = {
284                 .initialized = false,
285         },
286         .use_oif_addrs_only     = 0,
287         .ignore_routes_with_linkdown = 0,
288         .keep_addr_on_down      = 0,
289         .seg6_enabled           = 0,
290 #ifdef CONFIG_IPV6_SEG6_HMAC
291         .seg6_require_hmac      = 0,
292 #endif
293         .enhanced_dad           = 1,
294         .addr_gen_mode          = IN6_ADDR_GEN_MODE_EUI64,
295         .disable_policy         = 0,
296 };
297 
298 /* Check if link is ready: is it up and is a valid qdisc available */
299 static inline bool addrconf_link_ready(const struct net_device *dev)
300 {
301         return netif_oper_up(dev) && !qdisc_tx_is_noop(dev);
302 }
303 
304 static void addrconf_del_rs_timer(struct inet6_dev *idev)
305 {
306         if (del_timer(&idev->rs_timer))
307                 __in6_dev_put(idev);
308 }
309 
310 static void addrconf_del_dad_work(struct inet6_ifaddr *ifp)
311 {
312         if (cancel_delayed_work(&ifp->dad_work))
313                 __in6_ifa_put(ifp);
314 }
315 
316 static void addrconf_mod_rs_timer(struct inet6_dev *idev,
317                                   unsigned long when)
318 {
319         if (!timer_pending(&idev->rs_timer))
320                 in6_dev_hold(idev);
321         mod_timer(&idev->rs_timer, jiffies + when);
322 }
323 
324 static void addrconf_mod_dad_work(struct inet6_ifaddr *ifp,
325                                    unsigned long delay)
326 {
327         in6_ifa_hold(ifp);
328         if (mod_delayed_work(addrconf_wq, &ifp->dad_work, delay))
329                 in6_ifa_put(ifp);
330 }
331 
332 static int snmp6_alloc_dev(struct inet6_dev *idev)
333 {
334         int i;
335 
336         idev->stats.ipv6 = alloc_percpu(struct ipstats_mib);
337         if (!idev->stats.ipv6)
338                 goto err_ip;
339 
340         for_each_possible_cpu(i) {
341                 struct ipstats_mib *addrconf_stats;
342                 addrconf_stats = per_cpu_ptr(idev->stats.ipv6, i);
343                 u64_stats_init(&addrconf_stats->syncp);
344         }
345 
346 
347         idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
348                                         GFP_KERNEL);
349         if (!idev->stats.icmpv6dev)
350                 goto err_icmp;
351         idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
352                                            GFP_KERNEL);
353         if (!idev->stats.icmpv6msgdev)
354                 goto err_icmpmsg;
355 
356         return 0;
357 
358 err_icmpmsg:
359         kfree(idev->stats.icmpv6dev);
360 err_icmp:
361         free_percpu(idev->stats.ipv6);
362 err_ip:
363         return -ENOMEM;
364 }
365 
366 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
367 {
368         struct inet6_dev *ndev;
369         int err = -ENOMEM;
370 
371         ASSERT_RTNL();
372 
373         if (dev->mtu < IPV6_MIN_MTU)
374                 return ERR_PTR(-EINVAL);
375 
376         ndev = kzalloc(sizeof(struct inet6_dev), GFP_KERNEL);
377         if (!ndev)
378                 return ERR_PTR(err);
379 
380         rwlock_init(&ndev->lock);
381         ndev->dev = dev;
382         INIT_LIST_HEAD(&ndev->addr_list);
383         timer_setup(&ndev->rs_timer, addrconf_rs_timer, 0);
384         memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
385 
386         if (ndev->cnf.stable_secret.initialized)
387                 ndev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
388         else
389                 ndev->cnf.addr_gen_mode = ipv6_devconf_dflt.addr_gen_mode;
390 
391         ndev->cnf.mtu6 = dev->mtu;
392         ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
393         if (!ndev->nd_parms) {
394                 kfree(ndev);
395                 return ERR_PTR(err);
396         }
397         if (ndev->cnf.forwarding)
398                 dev_disable_lro(dev);
399         /* We refer to the device */
400         dev_hold(dev);
401 
402         if (snmp6_alloc_dev(ndev) < 0) {
403                 netdev_dbg(dev, "%s: cannot allocate memory for statistics\n",
404                            __func__);
405                 neigh_parms_release(&nd_tbl, ndev->nd_parms);
406                 dev_put(dev);
407                 kfree(ndev);
408                 return ERR_PTR(err);
409         }
410 
411         if (snmp6_register_dev(ndev) < 0) {
412                 netdev_dbg(dev, "%s: cannot create /proc/net/dev_snmp6/%s\n",
413                            __func__, dev->name);
414                 goto err_release;
415         }
416 
417         /* One reference from device. */
418         refcount_set(&ndev->refcnt, 1);
419 
420         if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
421                 ndev->cnf.accept_dad = -1;
422 
423 #if IS_ENABLED(CONFIG_IPV6_SIT)
424         if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
425                 pr_info("%s: Disabled Multicast RS\n", dev->name);
426                 ndev->cnf.rtr_solicits = 0;
427         }
428 #endif
429 
430         INIT_LIST_HEAD(&ndev->tempaddr_list);
431         ndev->desync_factor = U32_MAX;
432         if ((dev->flags&IFF_LOOPBACK) ||
433             dev->type == ARPHRD_TUNNEL ||
434             dev->type == ARPHRD_TUNNEL6 ||
435             dev->type == ARPHRD_SIT ||
436             dev->type == ARPHRD_NONE) {
437                 ndev->cnf.use_tempaddr = -1;
438         } else
439                 ipv6_regen_rndid(ndev);
440 
441         ndev->token = in6addr_any;
442 
443         if (netif_running(dev) && addrconf_link_ready(dev))
444                 ndev->if_flags |= IF_READY;
445 
446         ipv6_mc_init_dev(ndev);
447         ndev->tstamp = jiffies;
448         err = addrconf_sysctl_register(ndev);
449         if (err) {
450                 ipv6_mc_destroy_dev(ndev);
451                 snmp6_unregister_dev(ndev);
452                 goto err_release;
453         }
454         /* protected by rtnl_lock */
455         rcu_assign_pointer(dev->ip6_ptr, ndev);
456 
457         /* Join interface-local all-node multicast group */
458         ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes);
459 
460         /* Join all-node multicast group */
461         ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
462 
463         /* Join all-router multicast group if forwarding is set */
464         if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
465                 ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
466 
467         return ndev;
468 
469 err_release:
470         neigh_parms_release(&nd_tbl, ndev->nd_parms);
471         ndev->dead = 1;
472         in6_dev_finish_destroy(ndev);
473         return ERR_PTR(err);
474 }
475 
476 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
477 {
478         struct inet6_dev *idev;
479 
480         ASSERT_RTNL();
481 
482         idev = __in6_dev_get(dev);
483         if (!idev) {
484                 idev = ipv6_add_dev(dev);
485                 if (IS_ERR(idev))
486                         return NULL;
487         }
488 
489         if (dev->flags&IFF_UP)
490                 ipv6_mc_up(idev);
491         return idev;
492 }
493 
494 static int inet6_netconf_msgsize_devconf(int type)
495 {
496         int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
497                     + nla_total_size(4);        /* NETCONFA_IFINDEX */
498         bool all = false;
499 
500         if (type == NETCONFA_ALL)
501                 all = true;
502 
503         if (all || type == NETCONFA_FORWARDING)
504                 size += nla_total_size(4);
505 #ifdef CONFIG_IPV6_MROUTE
506         if (all || type == NETCONFA_MC_FORWARDING)
507                 size += nla_total_size(4);
508 #endif
509         if (all || type == NETCONFA_PROXY_NEIGH)
510                 size += nla_total_size(4);
511 
512         if (all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN)
513                 size += nla_total_size(4);
514 
515         return size;
516 }
517 
518 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
519                                       struct ipv6_devconf *devconf, u32 portid,
520                                       u32 seq, int event, unsigned int flags,
521                                       int type)
522 {
523         struct nlmsghdr  *nlh;
524         struct netconfmsg *ncm;
525         bool all = false;
526 
527         nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
528                         flags);
529         if (!nlh)
530                 return -EMSGSIZE;
531 
532         if (type == NETCONFA_ALL)
533                 all = true;
534 
535         ncm = nlmsg_data(nlh);
536         ncm->ncm_family = AF_INET6;
537 
538         if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
539                 goto nla_put_failure;
540 
541         if (!devconf)
542                 goto out;
543 
544         if ((all || type == NETCONFA_FORWARDING) &&
545             nla_put_s32(skb, NETCONFA_FORWARDING, devconf->forwarding) < 0)
546                 goto nla_put_failure;
547 #ifdef CONFIG_IPV6_MROUTE
548         if ((all || type == NETCONFA_MC_FORWARDING) &&
549             nla_put_s32(skb, NETCONFA_MC_FORWARDING,
550                         devconf->mc_forwarding) < 0)
551                 goto nla_put_failure;
552 #endif
553         if ((all || type == NETCONFA_PROXY_NEIGH) &&
554             nla_put_s32(skb, NETCONFA_PROXY_NEIGH, devconf->proxy_ndp) < 0)
555                 goto nla_put_failure;
556 
557         if ((all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN) &&
558             nla_put_s32(skb, NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
559                         devconf->ignore_routes_with_linkdown) < 0)
560                 goto nla_put_failure;
561 
562 out:
563         nlmsg_end(skb, nlh);
564         return 0;
565 
566 nla_put_failure:
567         nlmsg_cancel(skb, nlh);
568         return -EMSGSIZE;
569 }
570 
571 void inet6_netconf_notify_devconf(struct net *net, int event, int type,
572                                   int ifindex, struct ipv6_devconf *devconf)
573 {
574         struct sk_buff *skb;
575         int err = -ENOBUFS;
576 
577         skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_KERNEL);
578         if (!skb)
579                 goto errout;
580 
581         err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
582                                          event, 0, type);
583         if (err < 0) {
584                 /* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
585                 WARN_ON(err == -EMSGSIZE);
586                 kfree_skb(skb);
587                 goto errout;
588         }
589         rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_KERNEL);
590         return;
591 errout:
592         rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
593 }
594 
595 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
596         [NETCONFA_IFINDEX]      = { .len = sizeof(int) },
597         [NETCONFA_FORWARDING]   = { .len = sizeof(int) },
598         [NETCONFA_PROXY_NEIGH]  = { .len = sizeof(int) },
599         [NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN]  = { .len = sizeof(int) },
600 };
601 
602 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
603                                      struct nlmsghdr *nlh,
604                                      struct netlink_ext_ack *extack)
605 {
606         struct net *net = sock_net(in_skb->sk);
607         struct nlattr *tb[NETCONFA_MAX+1];
608         struct inet6_dev *in6_dev = NULL;
609         struct net_device *dev = NULL;
610         struct netconfmsg *ncm;
611         struct sk_buff *skb;
612         struct ipv6_devconf *devconf;
613         int ifindex;
614         int err;
615 
616         err = nlmsg_parse(nlh, sizeof(*ncm), tb, NETCONFA_MAX,
617                           devconf_ipv6_policy, extack);
618         if (err < 0)
619                 return err;
620 
621         if (!tb[NETCONFA_IFINDEX])
622                 return -EINVAL;
623 
624         err = -EINVAL;
625         ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
626         switch (ifindex) {
627         case NETCONFA_IFINDEX_ALL:
628                 devconf = net->ipv6.devconf_all;
629                 break;
630         case NETCONFA_IFINDEX_DEFAULT:
631                 devconf = net->ipv6.devconf_dflt;
632                 break;
633         default:
634                 dev = dev_get_by_index(net, ifindex);
635                 if (!dev)
636                         return -EINVAL;
637                 in6_dev = in6_dev_get(dev);
638                 if (!in6_dev)
639                         goto errout;
640                 devconf = &in6_dev->cnf;
641                 break;
642         }
643 
644         err = -ENOBUFS;
645         skb = nlmsg_new(inet6_netconf_msgsize_devconf(NETCONFA_ALL), GFP_KERNEL);
646         if (!skb)
647                 goto errout;
648 
649         err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
650                                          NETLINK_CB(in_skb).portid,
651                                          nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
652                                          NETCONFA_ALL);
653         if (err < 0) {
654                 /* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
655                 WARN_ON(err == -EMSGSIZE);
656                 kfree_skb(skb);
657                 goto errout;
658         }
659         err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
660 errout:
661         if (in6_dev)
662                 in6_dev_put(in6_dev);
663         if (dev)
664                 dev_put(dev);
665         return err;
666 }
667 
668 static int inet6_netconf_dump_devconf(struct sk_buff *skb,
669                                       struct netlink_callback *cb)
670 {
671         struct net *net = sock_net(skb->sk);
672         int h, s_h;
673         int idx, s_idx;
674         struct net_device *dev;
675         struct inet6_dev *idev;
676         struct hlist_head *head;
677 
678         s_h = cb->args[0];
679         s_idx = idx = cb->args[1];
680 
681         for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
682                 idx = 0;
683                 head = &net->dev_index_head[h];
684                 rcu_read_lock();
685                 cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^
686                           net->dev_base_seq;
687                 hlist_for_each_entry_rcu(dev, head, index_hlist) {
688                         if (idx < s_idx)
689                                 goto cont;
690                         idev = __in6_dev_get(dev);
691                         if (!idev)
692                                 goto cont;
693 
694                         if (inet6_netconf_fill_devconf(skb, dev->ifindex,
695                                                        &idev->cnf,
696                                                        NETLINK_CB(cb->skb).portid,
697                                                        cb->nlh->nlmsg_seq,
698                                                        RTM_NEWNETCONF,
699                                                        NLM_F_MULTI,
700                                                        NETCONFA_ALL) < 0) {
701                                 rcu_read_unlock();
702                                 goto done;
703                         }
704                         nl_dump_check_consistent(cb, nlmsg_hdr(skb));
705 cont:
706                         idx++;
707                 }
708                 rcu_read_unlock();
709         }
710         if (h == NETDEV_HASHENTRIES) {
711                 if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
712                                                net->ipv6.devconf_all,
713                                                NETLINK_CB(cb->skb).portid,
714                                                cb->nlh->nlmsg_seq,
715                                                RTM_NEWNETCONF, NLM_F_MULTI,
716                                                NETCONFA_ALL) < 0)
717                         goto done;
718                 else
719                         h++;
720         }
721         if (h == NETDEV_HASHENTRIES + 1) {
722                 if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
723                                                net->ipv6.devconf_dflt,
724                                                NETLINK_CB(cb->skb).portid,
725                                                cb->nlh->nlmsg_seq,
726                                                RTM_NEWNETCONF, NLM_F_MULTI,
727                                                NETCONFA_ALL) < 0)
728                         goto done;
729                 else
730                         h++;
731         }
732 done:
733         cb->args[0] = h;
734         cb->args[1] = idx;
735 
736         return skb->len;
737 }
738 
739 #ifdef CONFIG_SYSCTL
740 static void dev_forward_change(struct inet6_dev *idev)
741 {
742         struct net_device *dev;
743         struct inet6_ifaddr *ifa;
744 
745         if (!idev)
746                 return;
747         dev = idev->dev;
748         if (idev->cnf.forwarding)
749                 dev_disable_lro(dev);
750         if (dev->flags & IFF_MULTICAST) {
751                 if (idev->cnf.forwarding) {
752                         ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
753                         ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
754                         ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters);
755                 } else {
756                         ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
757                         ipv6_dev_mc_dec(dev, &in6addr_interfacelocal_allrouters);
758                         ipv6_dev_mc_dec(dev, &in6addr_sitelocal_allrouters);
759                 }
760         }
761 
762         list_for_each_entry(ifa, &idev->addr_list, if_list) {
763                 if (ifa->flags&IFA_F_TENTATIVE)
764                         continue;
765                 if (idev->cnf.forwarding)
766                         addrconf_join_anycast(ifa);
767                 else
768                         addrconf_leave_anycast(ifa);
769         }
770         inet6_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
771                                      NETCONFA_FORWARDING,
772                                      dev->ifindex, &idev->cnf);
773 }
774 
775 
776 static void addrconf_forward_change(struct net *net, __s32 newf)
777 {
778         struct net_device *dev;
779         struct inet6_dev *idev;
780 
781         for_each_netdev(net, dev) {
782                 idev = __in6_dev_get(dev);
783                 if (idev) {
784                         int changed = (!idev->cnf.forwarding) ^ (!newf);
785                         idev->cnf.forwarding = newf;
786                         if (changed)
787                                 dev_forward_change(idev);
788                 }
789         }
790 }
791 
792 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int newf)
793 {
794         struct net *net;
795         int old;
796 
797         if (!rtnl_trylock())
798                 return restart_syscall();
799 
800         net = (struct net *)table->extra2;
801         old = *p;
802         *p = newf;
803 
804         if (p == &net->ipv6.devconf_dflt->forwarding) {
805                 if ((!newf) ^ (!old))
806                         inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
807                                                      NETCONFA_FORWARDING,
808                                                      NETCONFA_IFINDEX_DEFAULT,
809                                                      net->ipv6.devconf_dflt);
810                 rtnl_unlock();
811                 return 0;
812         }
813 
814         if (p == &net->ipv6.devconf_all->forwarding) {
815                 int old_dflt = net->ipv6.devconf_dflt->forwarding;
816 
817                 net->ipv6.devconf_dflt->forwarding = newf;
818                 if ((!newf) ^ (!old_dflt))
819                         inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
820                                                      NETCONFA_FORWARDING,
821                                                      NETCONFA_IFINDEX_DEFAULT,
822                                                      net->ipv6.devconf_dflt);
823 
824                 addrconf_forward_change(net, newf);
825                 if ((!newf) ^ (!old))
826                         inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
827                                                      NETCONFA_FORWARDING,
828                                                      NETCONFA_IFINDEX_ALL,
829                                                      net->ipv6.devconf_all);
830         } else if ((!newf) ^ (!old))
831                 dev_forward_change((struct inet6_dev *)table->extra1);
832         rtnl_unlock();
833 
834         if (newf)
835                 rt6_purge_dflt_routers(net);
836         return 1;
837 }
838 
839 static void addrconf_linkdown_change(struct net *net, __s32 newf)
840 {
841         struct net_device *dev;
842         struct inet6_dev *idev;
843 
844         for_each_netdev(net, dev) {
845                 idev = __in6_dev_get(dev);
846                 if (idev) {
847                         int changed = (!idev->cnf.ignore_routes_with_linkdown) ^ (!newf);
848 
849                         idev->cnf.ignore_routes_with_linkdown = newf;
850                         if (changed)
851                                 inet6_netconf_notify_devconf(dev_net(dev),
852                                                              RTM_NEWNETCONF,
853                                                              NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
854                                                              dev->ifindex,
855                                                              &idev->cnf);
856                 }
857         }
858 }
859 
860 static int addrconf_fixup_linkdown(struct ctl_table *table, int *p, int newf)
861 {
862         struct net *net;
863         int old;
864 
865         if (!rtnl_trylock())
866                 return restart_syscall();
867 
868         net = (struct net *)table->extra2;
869         old = *p;
870         *p = newf;
871 
872         if (p == &net->ipv6.devconf_dflt->ignore_routes_with_linkdown) {
873                 if ((!newf) ^ (!old))
874                         inet6_netconf_notify_devconf(net,
875                                                      RTM_NEWNETCONF,
876                                                      NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
877                                                      NETCONFA_IFINDEX_DEFAULT,
878                                                      net->ipv6.devconf_dflt);
879                 rtnl_unlock();
880                 return 0;
881         }
882 
883         if (p == &net->ipv6.devconf_all->ignore_routes_with_linkdown) {
884                 net->ipv6.devconf_dflt->ignore_routes_with_linkdown = newf;
885                 addrconf_linkdown_change(net, newf);
886                 if ((!newf) ^ (!old))
887                         inet6_netconf_notify_devconf(net,
888                                                      RTM_NEWNETCONF,
889                                                      NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
890                                                      NETCONFA_IFINDEX_ALL,
891                                                      net->ipv6.devconf_all);
892         }
893         rtnl_unlock();
894 
895         return 1;
896 }
897 
898 #endif
899 
900 /* Nobody refers to this ifaddr, destroy it */
901 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
902 {
903         WARN_ON(!hlist_unhashed(&ifp->addr_lst));
904 
905 #ifdef NET_REFCNT_DEBUG
906         pr_debug("%s\n", __func__);
907 #endif
908 
909         in6_dev_put(ifp->idev);
910 
911         if (cancel_delayed_work(&ifp->dad_work))
912                 pr_notice("delayed DAD work was pending while freeing ifa=%p\n",
913                           ifp);
914 
915         if (ifp->state != INET6_IFADDR_STATE_DEAD) {
916                 pr_warn("Freeing alive inet6 address %p\n", ifp);
917                 return;
918         }
919         ip6_rt_put(ifp->rt);
920 
921         kfree_rcu(ifp, rcu);
922 }
923 
924 static void
925 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
926 {
927         struct list_head *p;
928         int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
929 
930         /*
931          * Each device address list is sorted in order of scope -
932          * global before linklocal.
933          */
934         list_for_each(p, &idev->addr_list) {
935                 struct inet6_ifaddr *ifa
936                         = list_entry(p, struct inet6_ifaddr, if_list);
937                 if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
938                         break;
939         }
940 
941         list_add_tail_rcu(&ifp->if_list, p);
942 }
943 
944 static u32 inet6_addr_hash(const struct net *net, const struct in6_addr *addr)
945 {
946         u32 val = ipv6_addr_hash(addr) ^ net_hash_mix(net);
947 
948         return hash_32(val, IN6_ADDR_HSIZE_SHIFT);
949 }
950 
951 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
952                                struct net_device *dev, unsigned int hash)
953 {
954         struct inet6_ifaddr *ifp;
955 
956         hlist_for_each_entry(ifp, &inet6_addr_lst[hash], addr_lst) {
957                 if (!net_eq(dev_net(ifp->idev->dev), net))
958                         continue;
959                 if (ipv6_addr_equal(&ifp->addr, addr)) {
960                         if (!dev || ifp->idev->dev == dev)
961                                 return true;
962                 }
963         }
964         return false;
965 }
966 
967 static int ipv6_add_addr_hash(struct net_device *dev, struct inet6_ifaddr *ifa)
968 {
969         unsigned int hash = inet6_addr_hash(dev_net(dev), &ifa->addr);
970         int err = 0;
971 
972         spin_lock(&addrconf_hash_lock);
973 
974         /* Ignore adding duplicate addresses on an interface */
975         if (ipv6_chk_same_addr(dev_net(dev), &ifa->addr, dev, hash)) {
976                 netdev_dbg(dev, "ipv6_add_addr: already assigned\n");
977                 err = -EEXIST;
978         } else {
979                 hlist_add_head_rcu(&ifa->addr_lst, &inet6_addr_lst[hash]);
980         }
981 
982         spin_unlock(&addrconf_hash_lock);
983 
984         return err;
985 }
986 
987 /* On success it returns ifp with increased reference count */
988 
989 static struct inet6_ifaddr *
990 ipv6_add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
991               const struct in6_addr *peer_addr, int pfxlen,
992               int scope, u32 flags, u32 valid_lft, u32 prefered_lft,
993               bool can_block, struct netlink_ext_ack *extack)
994 {
995         gfp_t gfp_flags = can_block ? GFP_KERNEL : GFP_ATOMIC;
996         struct net *net = dev_net(idev->dev);
997         struct inet6_ifaddr *ifa = NULL;
998         struct rt6_info *rt = NULL;
999         int err = 0;
1000         int addr_type = ipv6_addr_type(addr);
1001 
1002         if (addr_type == IPV6_ADDR_ANY ||
1003             addr_type & IPV6_ADDR_MULTICAST ||
1004             (!(idev->dev->flags & IFF_LOOPBACK) &&
1005              addr_type & IPV6_ADDR_LOOPBACK))
1006                 return ERR_PTR(-EADDRNOTAVAIL);
1007 
1008         if (idev->dead) {
1009                 err = -ENODEV;                  /*XXX*/
1010                 goto out;
1011         }
1012 
1013         if (idev->cnf.disable_ipv6) {
1014                 err = -EACCES;
1015                 goto out;
1016         }
1017 
1018         /* validator notifier needs to be blocking;
1019          * do not call in atomic context
1020          */
1021         if (can_block) {
1022                 struct in6_validator_info i6vi = {
1023                         .i6vi_addr = *addr,
1024                         .i6vi_dev = idev,
1025                         .extack = extack,
1026                 };
1027 
1028                 err = inet6addr_validator_notifier_call_chain(NETDEV_UP, &i6vi);
1029                 err = notifier_to_errno(err);
1030                 if (err < 0)
1031                         goto out;
1032         }
1033 
1034         ifa = kzalloc(sizeof(*ifa), gfp_flags);
1035         if (!ifa) {
1036                 err = -ENOBUFS;
1037                 goto out;
1038         }
1039 
1040         rt = addrconf_dst_alloc(idev, addr, false);
1041         if (IS_ERR(rt)) {
1042                 err = PTR_ERR(rt);
1043                 rt = NULL;
1044                 goto out;
1045         }
1046 
1047         if (net->ipv6.devconf_all->disable_policy ||
1048             idev->cnf.disable_policy)
1049                 rt->dst.flags |= DST_NOPOLICY;
1050 
1051         neigh_parms_data_state_setall(idev->nd_parms);
1052 
1053         ifa->addr = *addr;
1054         if (peer_addr)
1055                 ifa->peer_addr = *peer_addr;
1056 
1057         spin_lock_init(&ifa->lock);
1058         INIT_DELAYED_WORK(&ifa->dad_work, addrconf_dad_work);
1059         INIT_HLIST_NODE(&ifa->addr_lst);
1060         ifa->scope = scope;
1061         ifa->prefix_len = pfxlen;
1062         ifa->flags = flags;
1063         /* No need to add the TENTATIVE flag for addresses with NODAD */
1064         if (!(flags & IFA_F_NODAD))
1065                 ifa->flags |= IFA_F_TENTATIVE;
1066         ifa->valid_lft = valid_lft;
1067         ifa->prefered_lft = prefered_lft;
1068         ifa->cstamp = ifa->tstamp = jiffies;
1069         ifa->tokenized = false;
1070 
1071         ifa->rt = rt;
1072 
1073         ifa->idev = idev;
1074         in6_dev_hold(idev);
1075 
1076         /* For caller */
1077         refcount_set(&ifa->refcnt, 1);
1078 
1079         rcu_read_lock_bh();
1080 
1081         err = ipv6_add_addr_hash(idev->dev, ifa);
1082         if (err < 0) {
1083                 rcu_read_unlock_bh();
1084                 goto out;
1085         }
1086 
1087         write_lock(&idev->lock);
1088 
1089         /* Add to inet6_dev unicast addr list. */
1090         ipv6_link_dev_addr(idev, ifa);
1091 
1092         if (ifa->flags&IFA_F_TEMPORARY) {
1093                 list_add(&ifa->tmp_list, &idev->tempaddr_list);
1094                 in6_ifa_hold(ifa);
1095         }
1096 
1097         in6_ifa_hold(ifa);
1098         write_unlock(&idev->lock);
1099 
1100         rcu_read_unlock_bh();
1101 
1102         inet6addr_notifier_call_chain(NETDEV_UP, ifa);
1103 out:
1104         if (unlikely(err < 0)) {
1105                 if (rt)
1106                         ip6_rt_put(rt);
1107                 if (ifa) {
1108                         if (ifa->idev)
1109                                 in6_dev_put(ifa->idev);
1110                         kfree(ifa);
1111                 }
1112                 ifa = ERR_PTR(err);
1113         }
1114 
1115         return ifa;
1116 }
1117 
1118 enum cleanup_prefix_rt_t {
1119         CLEANUP_PREFIX_RT_NOP,    /* no cleanup action for prefix route */
1120         CLEANUP_PREFIX_RT_DEL,    /* delete the prefix route */
1121         CLEANUP_PREFIX_RT_EXPIRE, /* update the lifetime of the prefix route */
1122 };
1123 
1124 /*
1125  * Check, whether the prefix for ifp would still need a prefix route
1126  * after deleting ifp. The function returns one of the CLEANUP_PREFIX_RT_*
1127  * constants.
1128  *
1129  * 1) we don't purge prefix if address was not permanent.
1130  *    prefix is managed by its own lifetime.
1131  * 2) we also don't purge, if the address was IFA_F_NOPREFIXROUTE.
1132  * 3) if there are no addresses, delete prefix.
1133  * 4) if there are still other permanent address(es),
1134  *    corresponding prefix is still permanent.
1135  * 5) if there are still other addresses with IFA_F_NOPREFIXROUTE,
1136  *    don't purge the prefix, assume user space is managing it.
1137  * 6) otherwise, update prefix lifetime to the
1138  *    longest valid lifetime among the corresponding
1139  *    addresses on the device.
1140  *    Note: subsequent RA will update lifetime.
1141  **/
1142 static enum cleanup_prefix_rt_t
1143 check_cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long *expires)
1144 {
1145         struct inet6_ifaddr *ifa;
1146         struct inet6_dev *idev = ifp->idev;
1147         unsigned long lifetime;
1148         enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_DEL;
1149 
1150         *expires = jiffies;
1151 
1152         list_for_each_entry(ifa, &idev->addr_list, if_list) {
1153                 if (ifa == ifp)
1154                         continue;
1155                 if (!ipv6_prefix_equal(&ifa->addr, &ifp->addr,
1156                                        ifp->prefix_len))
1157                         continue;
1158                 if (ifa->flags & (IFA_F_PERMANENT | IFA_F_NOPREFIXROUTE))
1159                         return CLEANUP_PREFIX_RT_NOP;
1160 
1161                 action = CLEANUP_PREFIX_RT_EXPIRE;
1162 
1163                 spin_lock(&ifa->lock);
1164 
1165                 lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
1166                 /*
1167                  * Note: Because this address is
1168                  * not permanent, lifetime <
1169                  * LONG_MAX / HZ here.
1170                  */
1171                 if (time_before(*expires, ifa->tstamp + lifetime * HZ))
1172                         *expires = ifa->tstamp + lifetime * HZ;
1173                 spin_unlock(&ifa->lock);
1174         }
1175 
1176         return action;
1177 }
1178 
1179 static void
1180 cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long expires, bool del_rt)
1181 {
1182         struct rt6_info *rt;
1183 
1184         rt = addrconf_get_prefix_route(&ifp->addr,
1185                                        ifp->prefix_len,
1186                                        ifp->idev->dev,
1187                                        0, RTF_GATEWAY | RTF_DEFAULT);
1188         if (rt) {
1189                 if (del_rt)
1190                         ip6_del_rt(rt);
1191                 else {
1192                         if (!(rt->rt6i_flags & RTF_EXPIRES))
1193                                 rt6_set_expires(rt, expires);
1194                         ip6_rt_put(rt);
1195                 }
1196         }
1197 }
1198 
1199 
1200 /* This function wants to get referenced ifp and releases it before return */
1201 
1202 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
1203 {
1204         int state;
1205         enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_NOP;
1206         unsigned long expires;
1207 
1208         ASSERT_RTNL();
1209 
1210         spin_lock_bh(&ifp->lock);
1211         state = ifp->state;
1212         ifp->state = INET6_IFADDR_STATE_DEAD;
1213         spin_unlock_bh(&ifp->lock);
1214 
1215         if (state == INET6_IFADDR_STATE_DEAD)
1216                 goto out;
1217 
1218         spin_lock_bh(&addrconf_hash_lock);
1219         hlist_del_init_rcu(&ifp->addr_lst);
1220         spin_unlock_bh(&addrconf_hash_lock);
1221 
1222         write_lock_bh(&ifp->idev->lock);
1223 
1224         if (ifp->flags&IFA_F_TEMPORARY) {
1225                 list_del(&ifp->tmp_list);
1226                 if (ifp->ifpub) {
1227                         in6_ifa_put(ifp->ifpub);
1228                         ifp->ifpub = NULL;
1229                 }
1230                 __in6_ifa_put(ifp);
1231         }
1232 
1233         if (ifp->flags & IFA_F_PERMANENT && !(ifp->flags & IFA_F_NOPREFIXROUTE))
1234                 action = check_cleanup_prefix_route(ifp, &expires);
1235 
1236         list_del_rcu(&ifp->if_list);
1237         __in6_ifa_put(ifp);
1238 
1239         write_unlock_bh(&ifp->idev->lock);
1240 
1241         addrconf_del_dad_work(ifp);
1242 
1243         ipv6_ifa_notify(RTM_DELADDR, ifp);
1244 
1245         inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);
1246 
1247         if (action != CLEANUP_PREFIX_RT_NOP) {
1248                 cleanup_prefix_route(ifp, expires,
1249                         action == CLEANUP_PREFIX_RT_DEL);
1250         }
1251 
1252         /* clean up prefsrc entries */
1253         rt6_remove_prefsrc(ifp);
1254 out:
1255         in6_ifa_put(ifp);
1256 }
1257 
1258 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp,
1259                                 struct inet6_ifaddr *ift,
1260                                 bool block)
1261 {
1262         struct inet6_dev *idev = ifp->idev;
1263         struct in6_addr addr, *tmpaddr;
1264         unsigned long tmp_prefered_lft, tmp_valid_lft, tmp_tstamp, age;
1265         unsigned long regen_advance;
1266         int tmp_plen;
1267         int ret = 0;
1268         u32 addr_flags;
1269         unsigned long now = jiffies;
1270         long max_desync_factor;
1271         s32 cnf_temp_preferred_lft;
1272 
1273         write_lock_bh(&idev->lock);
1274         if (ift) {
1275                 spin_lock_bh(&ift->lock);
1276                 memcpy(&addr.s6_addr[8], &ift->addr.s6_addr[8], 8);
1277                 spin_unlock_bh(&ift->lock);
1278                 tmpaddr = &addr;
1279         } else {
1280                 tmpaddr = NULL;
1281         }
1282 retry:
1283         in6_dev_hold(idev);
1284         if (idev->cnf.use_tempaddr <= 0) {
1285                 write_unlock_bh(&idev->lock);
1286                 pr_info("%s: use_tempaddr is disabled\n", __func__);
1287                 in6_dev_put(idev);
1288                 ret = -1;
1289                 goto out;
1290         }
1291         spin_lock_bh(&ifp->lock);
1292         if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
1293                 idev->cnf.use_tempaddr = -1;    /*XXX*/
1294                 spin_unlock_bh(&ifp->lock);
1295                 write_unlock_bh(&idev->lock);
1296                 pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1297                         __func__);
1298                 in6_dev_put(idev);
1299                 ret = -1;
1300                 goto out;
1301         }
1302         in6_ifa_hold(ifp);
1303         memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1304         ipv6_try_regen_rndid(idev, tmpaddr);
1305         memcpy(&addr.s6_addr[8], idev->rndid, 8);
1306         age = (now - ifp->tstamp) / HZ;
1307 
1308         regen_advance = idev->cnf.regen_max_retry *
1309                         idev->cnf.dad_transmits *
1310                         NEIGH_VAR(idev->nd_parms, RETRANS_TIME) / HZ;
1311 
1312         /* recalculate max_desync_factor each time and update
1313          * idev->desync_factor if it's larger
1314          */
1315         cnf_temp_preferred_lft = READ_ONCE(idev->cnf.temp_prefered_lft);
1316         max_desync_factor = min_t(__u32,
1317                                   idev->cnf.max_desync_factor,
1318                                   cnf_temp_preferred_lft - regen_advance);
1319 
1320         if (unlikely(idev->desync_factor > max_desync_factor)) {
1321                 if (max_desync_factor > 0) {
1322                         get_random_bytes(&idev->desync_factor,
1323                                          sizeof(idev->desync_factor));
1324                         idev->desync_factor %= max_desync_factor;
1325                 } else {
1326                         idev->desync_factor = 0;
1327                 }
1328         }
1329 
1330         tmp_valid_lft = min_t(__u32,
1331                               ifp->valid_lft,
1332                               idev->cnf.temp_valid_lft + age);
1333         tmp_prefered_lft = cnf_temp_preferred_lft + age -
1334                             idev->desync_factor;
1335         tmp_prefered_lft = min_t(__u32, ifp->prefered_lft, tmp_prefered_lft);
1336         tmp_plen = ifp->prefix_len;
1337         tmp_tstamp = ifp->tstamp;
1338         spin_unlock_bh(&ifp->lock);
1339 
1340         write_unlock_bh(&idev->lock);
1341 
1342         /* A temporary address is created only if this calculated Preferred
1343          * Lifetime is greater than REGEN_ADVANCE time units.  In particular,
1344          * an implementation must not create a temporary address with a zero
1345          * Preferred Lifetime.
1346          * Use age calculation as in addrconf_verify to avoid unnecessary
1347          * temporary addresses being generated.
1348          */
1349         age = (now - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
1350         if (tmp_prefered_lft <= regen_advance + age) {
1351                 in6_ifa_put(ifp);
1352                 in6_dev_put(idev);
1353                 ret = -1;
1354                 goto out;
1355         }
1356 
1357         addr_flags = IFA_F_TEMPORARY;
1358         /* set in addrconf_prefix_rcv() */
1359         if (ifp->flags & IFA_F_OPTIMISTIC)
1360                 addr_flags |= IFA_F_OPTIMISTIC;
1361 
1362         ift = ipv6_add_addr(idev, &addr, NULL, tmp_plen,
1363                             ipv6_addr_scope(&addr), addr_flags,
1364                             tmp_valid_lft, tmp_prefered_lft, block, NULL);
1365         if (IS_ERR(ift)) {
1366                 in6_ifa_put(ifp);
1367                 in6_dev_put(idev);
1368                 pr_info("%s: retry temporary address regeneration\n", __func__);
1369                 tmpaddr = &addr;
1370                 write_lock_bh(&idev->lock);
1371                 goto retry;
1372         }
1373 
1374         spin_lock_bh(&ift->lock);
1375         ift->ifpub = ifp;
1376         ift->cstamp = now;
1377         ift->tstamp = tmp_tstamp;
1378         spin_unlock_bh(&ift->lock);
1379 
1380         addrconf_dad_start(ift);
1381         in6_ifa_put(ift);
1382         in6_dev_put(idev);
1383 out:
1384         return ret;
1385 }
1386 
1387 /*
1388  *      Choose an appropriate source address (RFC3484)
1389  */
1390 enum {
1391         IPV6_SADDR_RULE_INIT = 0,
1392         IPV6_SADDR_RULE_LOCAL,
1393         IPV6_SADDR_RULE_SCOPE,
1394         IPV6_SADDR_RULE_PREFERRED,
1395 #ifdef CONFIG_IPV6_MIP6
1396         IPV6_SADDR_RULE_HOA,
1397 #endif
1398         IPV6_SADDR_RULE_OIF,
1399         IPV6_SADDR_RULE_LABEL,
1400         IPV6_SADDR_RULE_PRIVACY,
1401         IPV6_SADDR_RULE_ORCHID,
1402         IPV6_SADDR_RULE_PREFIX,
1403 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1404         IPV6_SADDR_RULE_NOT_OPTIMISTIC,
1405 #endif
1406         IPV6_SADDR_RULE_MAX
1407 };
1408 
1409 struct ipv6_saddr_score {
1410         int                     rule;
1411         int                     addr_type;
1412         struct inet6_ifaddr     *ifa;
1413         DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1414         int                     scopedist;
1415         int                     matchlen;
1416 };
1417 
1418 struct ipv6_saddr_dst {
1419         const struct in6_addr *addr;
1420         int ifindex;
1421         int scope;
1422         int label;
1423         unsigned int prefs;
1424 };
1425 
1426 static inline int ipv6_saddr_preferred(int type)
1427 {
1428         if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1429                 return 1;
1430         return 0;
1431 }
1432 
1433 static bool ipv6_use_optimistic_addr(struct net *net,
1434                                      struct inet6_dev *idev)
1435 {
1436 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1437         if (!idev)
1438                 return false;
1439         if (!net->ipv6.devconf_all->optimistic_dad && !idev->cnf.optimistic_dad)
1440                 return false;
1441         if (!net->ipv6.devconf_all->use_optimistic && !idev->cnf.use_optimistic)
1442                 return false;
1443 
1444         return true;
1445 #else
1446         return false;
1447 #endif
1448 }
1449 
1450 static bool ipv6_allow_optimistic_dad(struct net *net,
1451                                       struct inet6_dev *idev)
1452 {
1453 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1454         if (!idev)
1455                 return false;
1456         if (!net->ipv6.devconf_all->optimistic_dad && !idev->cnf.optimistic_dad)
1457                 return false;
1458 
1459         return true;
1460 #else
1461         return false;
1462 #endif
1463 }
1464 
1465 static int ipv6_get_saddr_eval(struct net *net,
1466                                struct ipv6_saddr_score *score,
1467                                struct ipv6_saddr_dst *dst,
1468                                int i)
1469 {
1470         int ret;
1471 
1472         if (i <= score->rule) {
1473                 switch (i) {
1474                 case IPV6_SADDR_RULE_SCOPE:
1475                         ret = score->scopedist;
1476                         break;
1477                 case IPV6_SADDR_RULE_PREFIX:
1478                         ret = score->matchlen;
1479                         break;
1480                 default:
1481                         ret = !!test_bit(i, score->scorebits);
1482                 }
1483                 goto out;
1484         }
1485 
1486         switch (i) {
1487         case IPV6_SADDR_RULE_INIT:
1488                 /* Rule 0: remember if hiscore is not ready yet */
1489                 ret = !!score->ifa;
1490                 break;
1491         case IPV6_SADDR_RULE_LOCAL:
1492                 /* Rule 1: Prefer same address */
1493                 ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1494                 break;
1495         case IPV6_SADDR_RULE_SCOPE:
1496                 /* Rule 2: Prefer appropriate scope
1497                  *
1498                  *      ret
1499                  *       ^
1500                  *    -1 |  d 15
1501                  *    ---+--+-+---> scope
1502                  *       |
1503                  *       |             d is scope of the destination.
1504                  *  B-d  |  \
1505                  *       |   \      <- smaller scope is better if
1506                  *  B-15 |    \        if scope is enough for destination.
1507                  *       |             ret = B - scope (-1 <= scope >= d <= 15).
1508                  * d-C-1 | /
1509                  *       |/         <- greater is better
1510                  *   -C  /             if scope is not enough for destination.
1511                  *      /|             ret = scope - C (-1 <= d < scope <= 15).
1512                  *
1513                  * d - C - 1 < B -15 (for all -1 <= d <= 15).
1514                  * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1515                  * Assume B = 0 and we get C > 29.
1516                  */
1517                 ret = __ipv6_addr_src_scope(score->addr_type);
1518                 if (ret >= dst->scope)
1519                         ret = -ret;
1520                 else
1521                         ret -= 128;     /* 30 is enough */
1522                 score->scopedist = ret;
1523                 break;
1524         case IPV6_SADDR_RULE_PREFERRED:
1525             {
1526                 /* Rule 3: Avoid deprecated and optimistic addresses */
1527                 u8 avoid = IFA_F_DEPRECATED;
1528 
1529                 if (!ipv6_use_optimistic_addr(net, score->ifa->idev))
1530                         avoid |= IFA_F_OPTIMISTIC;
1531                 ret = ipv6_saddr_preferred(score->addr_type) ||
1532                       !(score->ifa->flags & avoid);
1533                 break;
1534             }
1535 #ifdef CONFIG_IPV6_MIP6
1536         case IPV6_SADDR_RULE_HOA:
1537             {
1538                 /* Rule 4: Prefer home address */
1539                 int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1540                 ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1541                 break;
1542             }
1543 #endif
1544         case IPV6_SADDR_RULE_OIF:
1545                 /* Rule 5: Prefer outgoing interface */
1546                 ret = (!dst->ifindex ||
1547                        dst->ifindex == score->ifa->idev->dev->ifindex);
1548                 break;
1549         case IPV6_SADDR_RULE_LABEL:
1550                 /* Rule 6: Prefer matching label */
1551                 ret = ipv6_addr_label(net,
1552                                       &score->ifa->addr, score->addr_type,
1553                                       score->ifa->idev->dev->ifindex) == dst->label;
1554                 break;
1555         case IPV6_SADDR_RULE_PRIVACY:
1556             {
1557                 /* Rule 7: Prefer public address
1558                  * Note: prefer temporary address if use_tempaddr >= 2
1559                  */
1560                 int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1561                                 !!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1562                                 score->ifa->idev->cnf.use_tempaddr >= 2;
1563                 ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1564                 break;
1565             }
1566         case IPV6_SADDR_RULE_ORCHID:
1567                 /* Rule 8-: Prefer ORCHID vs ORCHID or
1568                  *          non-ORCHID vs non-ORCHID
1569                  */
1570                 ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1571                         ipv6_addr_orchid(dst->addr));
1572                 break;
1573         case IPV6_SADDR_RULE_PREFIX:
1574                 /* Rule 8: Use longest matching prefix */
1575                 ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1576                 if (ret > score->ifa->prefix_len)
1577                         ret = score->ifa->prefix_len;
1578                 score->matchlen = ret;
1579                 break;
1580 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1581         case IPV6_SADDR_RULE_NOT_OPTIMISTIC:
1582                 /* Optimistic addresses still have lower precedence than other
1583                  * preferred addresses.
1584                  */
1585                 ret = !(score->ifa->flags & IFA_F_OPTIMISTIC);
1586                 break;
1587 #endif
1588         default:
1589                 ret = 0;
1590         }
1591 
1592         if (ret)
1593                 __set_bit(i, score->scorebits);
1594         score->rule = i;
1595 out:
1596         return ret;
1597 }
1598 
1599 static int __ipv6_dev_get_saddr(struct net *net,
1600                                 struct ipv6_saddr_dst *dst,
1601                                 struct inet6_dev *idev,
1602                                 struct ipv6_saddr_score *scores,
1603                                 int hiscore_idx)
1604 {
1605         struct ipv6_saddr_score *score = &scores[1 - hiscore_idx], *hiscore = &scores[hiscore_idx];
1606 
1607         list_for_each_entry_rcu(score->ifa, &idev->addr_list, if_list) {
1608                 int i;
1609 
1610                 /*
1611                  * - Tentative Address (RFC2462 section 5.4)
1612                  *  - A tentative address is not considered
1613                  *    "assigned to an interface" in the traditional
1614                  *    sense, unless it is also flagged as optimistic.
1615                  * - Candidate Source Address (section 4)
1616                  *  - In any case, anycast addresses, multicast
1617                  *    addresses, and the unspecified address MUST
1618                  *    NOT be included in a candidate set.
1619                  */
1620                 if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1621                     (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1622                         continue;
1623 
1624                 score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1625 
1626                 if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1627                              score->addr_type & IPV6_ADDR_MULTICAST)) {
1628                         net_dbg_ratelimited("ADDRCONF: unspecified / multicast address assigned as unicast address on %s",
1629                                             idev->dev->name);
1630                         continue;
1631                 }
1632 
1633                 score->rule = -1;
1634                 bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1635 
1636                 for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1637                         int minihiscore, miniscore;
1638 
1639                         minihiscore = ipv6_get_saddr_eval(net, hiscore, dst, i);
1640                         miniscore = ipv6_get_saddr_eval(net, score, dst, i);
1641 
1642                         if (minihiscore > miniscore) {
1643                                 if (i == IPV6_SADDR_RULE_SCOPE &&
1644                                     score->scopedist > 0) {
1645                                         /*
1646                                          * special case:
1647                                          * each remaining entry
1648                                          * has too small (not enough)
1649                                          * scope, because ifa entries
1650                                          * are sorted by their scope
1651                                          * values.
1652                                          */
1653                                         goto out;
1654                                 }
1655                                 break;
1656                         } else if (minihiscore < miniscore) {
1657                                 swap(hiscore, score);
1658                                 hiscore_idx = 1 - hiscore_idx;
1659 
1660                                 /* restore our iterator */
1661                                 score->ifa = hiscore->ifa;
1662 
1663                                 break;
1664                         }
1665                 }
1666         }
1667 out:
1668         return hiscore_idx;
1669 }
1670 
1671 static int ipv6_get_saddr_master(struct net *net,
1672                                  const struct net_device *dst_dev,
1673                                  const struct net_device *master,
1674                                  struct ipv6_saddr_dst *dst,
1675                                  struct ipv6_saddr_score *scores,
1676                                  int hiscore_idx)
1677 {
1678         struct inet6_dev *idev;
1679 
1680         idev = __in6_dev_get(dst_dev);
1681         if (idev)
1682                 hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1683                                                    scores, hiscore_idx);
1684 
1685         idev = __in6_dev_get(master);
1686         if (idev)
1687                 hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1688                                                    scores, hiscore_idx);
1689 
1690         return hiscore_idx;
1691 }
1692 
1693 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1694                        const struct in6_addr *daddr, unsigned int prefs,
1695                        struct in6_addr *saddr)
1696 {
1697         struct ipv6_saddr_score scores[2], *hiscore;
1698         struct ipv6_saddr_dst dst;
1699         struct inet6_dev *idev;
1700         struct net_device *dev;
1701         int dst_type;
1702         bool use_oif_addr = false;
1703         int hiscore_idx = 0;
1704         int ret = 0;
1705 
1706         dst_type = __ipv6_addr_type(daddr);
1707         dst.addr = daddr;
1708         dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1709         dst.scope = __ipv6_addr_src_scope(dst_type);
1710         dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1711         dst.prefs = prefs;
1712 
1713         scores[hiscore_idx].rule = -1;
1714         scores[hiscore_idx].ifa = NULL;
1715 
1716         rcu_read_lock();
1717 
1718         /* Candidate Source Address (section 4)
1719          *  - multicast and link-local destination address,
1720          *    the set of candidate source address MUST only
1721          *    include addresses assigned to interfaces
1722          *    belonging to the same link as the outgoing
1723          *    interface.
1724          * (- For site-local destination addresses, the
1725          *    set of candidate source addresses MUST only
1726          *    include addresses assigned to interfaces
1727          *    belonging to the same site as the outgoing
1728          *    interface.)
1729          *  - "It is RECOMMENDED that the candidate source addresses
1730          *    be the set of unicast addresses assigned to the
1731          *    interface that will be used to send to the destination
1732          *    (the 'outgoing' interface)." (RFC 6724)
1733          */
1734         if (dst_dev) {
1735                 idev = __in6_dev_get(dst_dev);
1736                 if ((dst_type & IPV6_ADDR_MULTICAST) ||
1737                     dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL ||
1738                     (idev && idev->cnf.use_oif_addrs_only)) {
1739                         use_oif_addr = true;
1740                 }
1741         }
1742 
1743         if (use_oif_addr) {
1744                 if (idev)
1745                         hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1746         } else {
1747                 const struct net_device *master;
1748                 int master_idx = 0;
1749 
1750                 /* if dst_dev exists and is enslaved to an L3 device, then
1751                  * prefer addresses from dst_dev and then the master over
1752                  * any other enslaved devices in the L3 domain.
1753                  */
1754                 master = l3mdev_master_dev_rcu(dst_dev);
1755                 if (master) {
1756                         master_idx = master->ifindex;
1757 
1758                         hiscore_idx = ipv6_get_saddr_master(net, dst_dev,
1759                                                             master, &dst,
1760                                                             scores, hiscore_idx);
1761 
1762                         if (scores[hiscore_idx].ifa)
1763                                 goto out;
1764                 }
1765 
1766                 for_each_netdev_rcu(net, dev) {
1767                         /* only consider addresses on devices in the
1768                          * same L3 domain
1769                          */
1770                         if (l3mdev_master_ifindex_rcu(dev) != master_idx)
1771                                 continue;
1772                         idev = __in6_dev_get(dev);
1773                         if (!idev)
1774                                 continue;
1775                         hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1776                 }
1777         }
1778 
1779 out:
1780         hiscore = &scores[hiscore_idx];
1781         if (!hiscore->ifa)
1782                 ret = -EADDRNOTAVAIL;
1783         else
1784                 *saddr = hiscore->ifa->addr;
1785 
1786         rcu_read_unlock();
1787         return ret;
1788 }
1789 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1790 
1791 int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr,
1792                       u32 banned_flags)
1793 {
1794         struct inet6_ifaddr *ifp;
1795         int err = -EADDRNOTAVAIL;
1796 
1797         list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1798                 if (ifp->scope > IFA_LINK)
1799                         break;
1800                 if (ifp->scope == IFA_LINK &&
1801                     !(ifp->flags & banned_flags)) {
1802                         *addr = ifp->addr;
1803                         err = 0;
1804                         break;
1805                 }
1806         }
1807         return err;
1808 }
1809 
1810 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1811                     u32 banned_flags)
1812 {
1813         struct inet6_dev *idev;
1814         int err = -EADDRNOTAVAIL;
1815 
1816         rcu_read_lock();
1817         idev = __in6_dev_get(dev);
1818         if (idev) {
1819                 read_lock_bh(&idev->lock);
1820                 err = __ipv6_get_lladdr(idev, addr, banned_flags);
1821                 read_unlock_bh(&idev->lock);
1822         }
1823         rcu_read_unlock();
1824         return err;
1825 }
1826 
1827 static int ipv6_count_addresses(const struct inet6_dev *idev)
1828 {
1829         const struct inet6_ifaddr *ifp;
1830         int cnt = 0;
1831 
1832         rcu_read_lock();
1833         list_for_each_entry_rcu(ifp, &idev->addr_list, if_list)
1834                 cnt++;
1835         rcu_read_unlock();
1836         return cnt;
1837 }
1838 
1839 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1840                   const struct net_device *dev, int strict)
1841 {
1842         return ipv6_chk_addr_and_flags(net, addr, dev, !dev,
1843                                        strict, IFA_F_TENTATIVE);
1844 }
1845 EXPORT_SYMBOL(ipv6_chk_addr);
1846 
1847 /* device argument is used to find the L3 domain of interest. If
1848  * skip_dev_check is set, then the ifp device is not checked against
1849  * the passed in dev argument. So the 2 cases for addresses checks are:
1850  *   1. does the address exist in the L3 domain that dev is part of
1851  *      (skip_dev_check = true), or
1852  *
1853  *   2. does the address exist on the specific device
1854  *      (skip_dev_check = false)
1855  */
1856 int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
1857                             const struct net_device *dev, bool skip_dev_check,
1858                             int strict, u32 banned_flags)
1859 {
1860         unsigned int hash = inet6_addr_hash(net, addr);
1861         const struct net_device *l3mdev;
1862         struct inet6_ifaddr *ifp;
1863         u32 ifp_flags;
1864 
1865         rcu_read_lock();
1866 
1867         l3mdev = l3mdev_master_dev_rcu(dev);
1868         if (skip_dev_check)
1869                 dev = NULL;
1870 
1871         hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
1872                 if (!net_eq(dev_net(ifp->idev->dev), net))
1873                         continue;
1874 
1875                 if (l3mdev_master_dev_rcu(ifp->idev->dev) != l3mdev)
1876                         continue;
1877 
1878                 /* Decouple optimistic from tentative for evaluation here.
1879                  * Ban optimistic addresses explicitly, when required.
1880                  */
1881                 ifp_flags = (ifp->flags&IFA_F_OPTIMISTIC)
1882                             ? (ifp->flags&~IFA_F_TENTATIVE)
1883                             : ifp->flags;
1884                 if (ipv6_addr_equal(&ifp->addr, addr) &&
1885                     !(ifp_flags&banned_flags) &&
1886                     (!dev || ifp->idev->dev == dev ||
1887                      !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1888                         rcu_read_unlock();
1889                         return 1;
1890                 }
1891         }
1892 
1893         rcu_read_unlock();
1894         return 0;
1895 }
1896 EXPORT_SYMBOL(ipv6_chk_addr_and_flags);
1897 
1898 
1899 /* Compares an address/prefix_len with addresses on device @dev.
1900  * If one is found it returns true.
1901  */
1902 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
1903         const unsigned int prefix_len, struct net_device *dev)
1904 {
1905         const struct inet6_ifaddr *ifa;
1906         const struct inet6_dev *idev;
1907         bool ret = false;
1908 
1909         rcu_read_lock();
1910         idev = __in6_dev_get(dev);
1911         if (idev) {
1912                 list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
1913                         ret = ipv6_prefix_equal(addr, &ifa->addr, prefix_len);
1914                         if (ret)
1915                                 break;
1916                 }
1917         }
1918         rcu_read_unlock();
1919 
1920         return ret;
1921 }
1922 EXPORT_SYMBOL(ipv6_chk_custom_prefix);
1923 
1924 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
1925 {
1926         const struct inet6_ifaddr *ifa;
1927         const struct inet6_dev *idev;
1928         int     onlink;
1929 
1930         onlink = 0;
1931         rcu_read_lock();
1932         idev = __in6_dev_get(dev);
1933         if (idev) {
1934                 list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
1935                         onlink = ipv6_prefix_equal(addr, &ifa->addr,
1936                                                    ifa->prefix_len);
1937                         if (onlink)
1938                                 break;
1939                 }
1940         }
1941         rcu_read_unlock();
1942         return onlink;
1943 }
1944 EXPORT_SYMBOL(ipv6_chk_prefix);
1945 
1946 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
1947                                      struct net_device *dev, int strict)
1948 {
1949         unsigned int hash = inet6_addr_hash(net, addr);
1950         struct inet6_ifaddr *ifp, *result = NULL;
1951 
1952         rcu_read_lock();
1953         hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
1954                 if (!net_eq(dev_net(ifp->idev->dev), net))
1955                         continue;
1956                 if (ipv6_addr_equal(&ifp->addr, addr)) {
1957                         if (!dev || ifp->idev->dev == dev ||
1958                             !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
1959                                 result = ifp;
1960                                 in6_ifa_hold(ifp);
1961                                 break;
1962                         }
1963                 }
1964         }
1965         rcu_read_unlock();
1966 
1967         return result;
1968 }
1969 
1970 /* Gets referenced address, destroys ifaddr */
1971 
1972 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
1973 {
1974         if (dad_failed)
1975                 ifp->flags |= IFA_F_DADFAILED;
1976 
1977         if (ifp->flags&IFA_F_TEMPORARY) {
1978                 struct inet6_ifaddr *ifpub;
1979                 spin_lock_bh(&ifp->lock);
1980                 ifpub = ifp->ifpub;
1981                 if (ifpub) {
1982                         in6_ifa_hold(ifpub);
1983                         spin_unlock_bh(&ifp->lock);
1984                         ipv6_create_tempaddr(ifpub, ifp, true);
1985                         in6_ifa_put(ifpub);
1986                 } else {
1987                         spin_unlock_bh(&ifp->lock);
1988                 }
1989                 ipv6_del_addr(ifp);
1990         } else if (ifp->flags&IFA_F_PERMANENT || !dad_failed) {
1991                 spin_lock_bh(&ifp->lock);
1992                 addrconf_del_dad_work(ifp);
1993                 ifp->flags |= IFA_F_TENTATIVE;
1994                 if (dad_failed)
1995                         ifp->flags &= ~IFA_F_OPTIMISTIC;
1996                 spin_unlock_bh(&ifp->lock);
1997                 if (dad_failed)
1998                         ipv6_ifa_notify(0, ifp);
1999                 in6_ifa_put(ifp);
2000         } else {
2001                 ipv6_del_addr(ifp);
2002         }
2003 }
2004 
2005 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
2006 {
2007         int err = -ENOENT;
2008 
2009         spin_lock_bh(&ifp->lock);
2010         if (ifp->state == INET6_IFADDR_STATE_DAD) {
2011                 ifp->state = INET6_IFADDR_STATE_POSTDAD;
2012                 err = 0;
2013         }
2014         spin_unlock_bh(&ifp->lock);
2015 
2016         return err;
2017 }
2018 
2019 void addrconf_dad_failure(struct sk_buff *skb, struct inet6_ifaddr *ifp)
2020 {
2021         struct inet6_dev *idev = ifp->idev;
2022         struct net *net = dev_net(ifp->idev->dev);
2023 
2024         if (addrconf_dad_end(ifp)) {
2025                 in6_ifa_put(ifp);
2026                 return;
2027         }
2028 
2029         net_info_ratelimited("%s: IPv6 duplicate address %pI6c used by %pM detected!\n",
2030                              ifp->idev->dev->name, &ifp->addr, eth_hdr(skb)->h_source);
2031 
2032         spin_lock_bh(&ifp->lock);
2033 
2034         if (ifp->flags & IFA_F_STABLE_PRIVACY) {
2035                 int scope = ifp->scope;
2036                 u32 flags = ifp->flags;
2037                 struct in6_addr new_addr;
2038                 struct inet6_ifaddr *ifp2;
2039                 u32 valid_lft, preferred_lft;
2040                 int pfxlen = ifp->prefix_len;
2041                 int retries = ifp->stable_privacy_retry + 1;
2042 
2043                 if (retries > net->ipv6.sysctl.idgen_retries) {
2044                         net_info_ratelimited("%s: privacy stable address generation failed because of DAD conflicts!\n",
2045                                              ifp->idev->dev->name);
2046                         goto errdad;
2047                 }
2048 
2049                 new_addr = ifp->addr;
2050                 if (ipv6_generate_stable_address(&new_addr, retries,
2051                                                  idev))
2052                         goto errdad;
2053 
2054                 valid_lft = ifp->valid_lft;
2055                 preferred_lft = ifp->prefered_lft;
2056 
2057                 spin_unlock_bh(&ifp->lock);
2058 
2059                 if (idev->cnf.max_addresses &&
2060                     ipv6_count_addresses(idev) >=
2061                     idev->cnf.max_addresses)
2062                         goto lock_errdad;
2063 
2064                 net_info_ratelimited("%s: generating new stable privacy address because of DAD conflict\n",
2065                                      ifp->idev->dev->name);
2066 
2067                 ifp2 = ipv6_add_addr(idev, &new_addr, NULL, pfxlen,
2068                                      scope, flags, valid_lft,
2069                                      preferred_lft, false, NULL);
2070                 if (IS_ERR(ifp2))
2071                         goto lock_errdad;
2072 
2073                 spin_lock_bh(&ifp2->lock);
2074                 ifp2->stable_privacy_retry = retries;
2075                 ifp2->state = INET6_IFADDR_STATE_PREDAD;
2076                 spin_unlock_bh(&ifp2->lock);
2077 
2078                 addrconf_mod_dad_work(ifp2, net->ipv6.sysctl.idgen_delay);
2079                 in6_ifa_put(ifp2);
2080 lock_errdad:
2081                 spin_lock_bh(&ifp->lock);
2082         }
2083 
2084 errdad:
2085         /* transition from _POSTDAD to _ERRDAD */
2086         ifp->state = INET6_IFADDR_STATE_ERRDAD;
2087         spin_unlock_bh(&ifp->lock);
2088 
2089         addrconf_mod_dad_work(ifp, 0);
2090         in6_ifa_put(ifp);
2091 }
2092 
2093 /* Join to solicited addr multicast group.
2094  * caller must hold RTNL */
2095 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
2096 {
2097         struct in6_addr maddr;
2098 
2099         if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2100                 return;
2101 
2102         addrconf_addr_solict_mult(addr, &maddr);
2103         ipv6_dev_mc_inc(dev, &maddr);
2104 }
2105 
2106 /* caller must hold RTNL */
2107 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
2108 {
2109         struct in6_addr maddr;
2110 
2111         if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2112                 return;
2113 
2114         addrconf_addr_solict_mult(addr, &maddr);
2115         __ipv6_dev_mc_dec(idev, &maddr);
2116 }
2117 
2118 /* caller must hold RTNL */
2119 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
2120 {
2121         struct in6_addr addr;
2122 
2123         if (ifp->prefix_len >= 127) /* RFC 6164 */
2124                 return;
2125         ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2126         if (ipv6_addr_any(&addr))
2127                 return;
2128         __ipv6_dev_ac_inc(ifp->idev, &addr);
2129 }
2130 
2131 /* caller must hold RTNL */
2132 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
2133 {
2134         struct in6_addr addr;
2135 
2136         if (ifp->prefix_len >= 127) /* RFC 6164 */
2137                 return;
2138         ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2139         if (ipv6_addr_any(&addr))
2140                 return;
2141         __ipv6_dev_ac_dec(ifp->idev, &addr);
2142 }
2143 
2144 static int addrconf_ifid_6lowpan(u8 *eui, struct net_device *dev)
2145 {
2146         switch (dev->addr_len) {
2147         case ETH_ALEN:
2148                 memcpy(eui, dev->dev_addr, 3);
2149                 eui[3] = 0xFF;
2150                 eui[4] = 0xFE;
2151                 memcpy(eui + 5, dev->dev_addr + 3, 3);
2152                 break;
2153         case EUI64_ADDR_LEN:
2154                 memcpy(eui, dev->dev_addr, EUI64_ADDR_LEN);
2155                 eui[0] ^= 2;
2156                 break;
2157         default:
2158                 return -1;
2159         }
2160 
2161         return 0;
2162 }
2163 
2164 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
2165 {
2166         union fwnet_hwaddr *ha;
2167 
2168         if (dev->addr_len != FWNET_ALEN)
2169                 return -1;
2170 
2171         ha = (union fwnet_hwaddr *)dev->dev_addr;
2172 
2173         memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
2174         eui[0] ^= 2;
2175         return 0;
2176 }
2177 
2178 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
2179 {
2180         /* XXX: inherit EUI-64 from other interface -- yoshfuji */
2181         if (dev->addr_len != ARCNET_ALEN)
2182                 return -1;
2183         memset(eui, 0, 7);
2184         eui[7] = *(u8 *)dev->dev_addr;
2185         return 0;
2186 }
2187 
2188 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
2189 {
2190         if (dev->addr_len != INFINIBAND_ALEN)
2191                 return -1;
2192         memcpy(eui, dev->dev_addr + 12, 8);
2193         eui[0] |= 2;
2194         return 0;
2195 }
2196 
2197 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
2198 {
2199         if (addr == 0)
2200                 return -1;
2201         eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
2202                   ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
2203                   ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
2204                   ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
2205                   ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
2206                   ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
2207         eui[1] = 0;
2208         eui[2] = 0x5E;
2209         eui[3] = 0xFE;
2210         memcpy(eui + 4, &addr, 4);
2211         return 0;
2212 }
2213 
2214 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
2215 {
2216         if (dev->priv_flags & IFF_ISATAP)
2217                 return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2218         return -1;
2219 }
2220 
2221 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
2222 {
2223         return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2224 }
2225 
2226 static int addrconf_ifid_ip6tnl(u8 *eui, struct net_device *dev)
2227 {
2228         memcpy(eui, dev->perm_addr, 3);
2229         memcpy(eui + 5, dev->perm_addr + 3, 3);
2230         eui[3] = 0xFF;
2231         eui[4] = 0xFE;
2232         eui[0] ^= 2;
2233         return 0;
2234 }
2235 
2236 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
2237 {
2238         switch (dev->type) {
2239         case ARPHRD_ETHER:
2240         case ARPHRD_FDDI:
2241                 return addrconf_ifid_eui48(eui, dev);
2242         case ARPHRD_ARCNET:
2243                 return addrconf_ifid_arcnet(eui, dev);
2244         case ARPHRD_INFINIBAND:
2245                 return addrconf_ifid_infiniband(eui, dev);
2246         case ARPHRD_SIT:
2247                 return addrconf_ifid_sit(eui, dev);
2248         case ARPHRD_IPGRE:
2249         case ARPHRD_TUNNEL:
2250                 return addrconf_ifid_gre(eui, dev);
2251         case ARPHRD_6LOWPAN:
2252                 return addrconf_ifid_6lowpan(eui, dev);
2253         case ARPHRD_IEEE1394:
2254                 return addrconf_ifid_ieee1394(eui, dev);
2255         case ARPHRD_TUNNEL6:
2256         case ARPHRD_IP6GRE:
2257                 return addrconf_ifid_ip6tnl(eui, dev);
2258         }
2259         return -1;
2260 }
2261 
2262 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
2263 {
2264         int err = -1;
2265         struct inet6_ifaddr *ifp;
2266 
2267         read_lock_bh(&idev->lock);
2268         list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
2269                 if (ifp->scope > IFA_LINK)
2270                         break;
2271                 if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
2272                         memcpy(eui, ifp->addr.s6_addr+8, 8);
2273                         err = 0;
2274                         break;
2275                 }
2276         }
2277         read_unlock_bh(&idev->lock);
2278         return err;
2279 }
2280 
2281 /* (re)generation of randomized interface identifier (RFC 3041 3.2, 3.5) */
2282 static void ipv6_regen_rndid(struct inet6_dev *idev)
2283 {
2284 regen:
2285         get_random_bytes(idev->rndid, sizeof(idev->rndid));
2286         idev->rndid[0] &= ~0x02;
2287 
2288         /*
2289          * <draft-ietf-ipngwg-temp-addresses-v2-00.txt>:
2290          * check if generated address is not inappropriate
2291          *
2292          *  - Reserved subnet anycast (RFC 2526)
2293          *      11111101 11....11 1xxxxxxx
2294          *  - ISATAP (RFC4214) 6.1
2295          *      00-00-5E-FE-xx-xx-xx-xx
2296          *  - value 0
2297          *  - XXX: already assigned to an address on the device
2298          */
2299         if (idev->rndid[0] == 0xfd &&
2300             (idev->rndid[1]&idev->rndid[2]&idev->rndid[3]&idev->rndid[4]&idev->rndid[5]&idev->rndid[6]) == 0xff &&
2301             (idev->rndid[7]&0x80))
2302                 goto regen;
2303         if ((idev->rndid[0]|idev->rndid[1]) == 0) {
2304                 if (idev->rndid[2] == 0x5e && idev->rndid[3] == 0xfe)
2305                         goto regen;
2306                 if ((idev->rndid[2]|idev->rndid[3]|idev->rndid[4]|idev->rndid[5]|idev->rndid[6]|idev->rndid[7]) == 0x00)
2307                         goto regen;
2308         }
2309 }
2310 
2311 static void  ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr)
2312 {
2313         if (tmpaddr && memcmp(idev->rndid, &tmpaddr->s6_addr[8], 8) == 0)
2314                 ipv6_regen_rndid(idev);
2315 }
2316 
2317 /*
2318  *      Add prefix route.
2319  */
2320 
2321 static void
2322 addrconf_prefix_route(struct in6_addr *pfx, int plen, struct net_device *dev,
2323                       unsigned long expires, u32 flags)
2324 {
2325         struct fib6_config cfg = {
2326                 .fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX,
2327                 .fc_metric = IP6_RT_PRIO_ADDRCONF,
2328                 .fc_ifindex = dev->ifindex,
2329                 .fc_expires = expires,
2330                 .fc_dst_len = plen,
2331                 .fc_flags = RTF_UP | flags,
2332                 .fc_nlinfo.nl_net = dev_net(dev),
2333                 .fc_protocol = RTPROT_KERNEL,
2334         };
2335 
2336         cfg.fc_dst = *pfx;
2337 
2338         /* Prevent useless cloning on PtP SIT.
2339            This thing is done here expecting that the whole
2340            class of non-broadcast devices need not cloning.
2341          */
2342 #if IS_ENABLED(CONFIG_IPV6_SIT)
2343         if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
2344                 cfg.fc_flags |= RTF_NONEXTHOP;
2345 #endif
2346 
2347         ip6_route_add(&cfg, NULL);
2348 }
2349 
2350 
2351 static struct rt6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
2352                                                   int plen,
2353                                                   const struct net_device *dev,
2354                                                   u32 flags, u32 noflags)
2355 {
2356         struct fib6_node *fn;
2357         struct rt6_info *rt = NULL;
2358         struct fib6_table *table;
2359         u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX;
2360 
2361         table = fib6_get_table(dev_net(dev), tb_id);
2362         if (!table)
2363                 return NULL;
2364 
2365         rcu_read_lock();
2366         fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0, true);
2367         if (!fn)
2368                 goto out;
2369 
2370         for_each_fib6_node_rt_rcu(fn) {
2371                 if (rt->dst.dev->ifindex != dev->ifindex)
2372                         continue;
2373                 if ((rt->rt6i_flags & flags) != flags)
2374                         continue;
2375                 if ((rt->rt6i_flags & noflags) != 0)
2376                         continue;
2377                 if (!dst_hold_safe(&rt->dst))
2378                         rt = NULL;
2379                 break;
2380         }
2381 out:
2382         rcu_read_unlock();
2383         return rt;
2384 }
2385 
2386 
2387 /* Create "default" multicast route to the interface */
2388 
2389 static void addrconf_add_mroute(struct net_device *dev)
2390 {
2391         struct fib6_config cfg = {
2392                 .fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_LOCAL,
2393                 .fc_metric = IP6_RT_PRIO_ADDRCONF,
2394                 .fc_ifindex = dev->ifindex,
2395                 .fc_dst_len = 8,
2396                 .fc_flags = RTF_UP,
2397                 .fc_nlinfo.nl_net = dev_net(dev),
2398         };
2399 
2400         ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
2401 
2402         ip6_route_add(&cfg, NULL);
2403 }
2404 
2405 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2406 {
2407         struct inet6_dev *idev;
2408 
2409         ASSERT_RTNL();
2410 
2411         idev = ipv6_find_idev(dev);
2412         if (!idev)
2413                 return ERR_PTR(-ENOBUFS);
2414 
2415         if (idev->cnf.disable_ipv6)
2416                 return ERR_PTR(-EACCES);
2417 
2418         /* Add default multicast route */
2419         if (!(dev->flags & IFF_LOOPBACK) && !netif_is_l3_master(dev))
2420                 addrconf_add_mroute(dev);
2421 
2422         return idev;
2423 }
2424 
2425 static void manage_tempaddrs(struct inet6_dev *idev,
2426                              struct inet6_ifaddr *ifp,
2427                              __u32 valid_lft, __u32 prefered_lft,
2428                              bool create, unsigned long now)
2429 {
2430         u32 flags;
2431         struct inet6_ifaddr *ift;
2432 
2433         read_lock_bh(&idev->lock);
2434         /* update all temporary addresses in the list */
2435         list_for_each_entry(ift, &idev->tempaddr_list, tmp_list) {
2436                 int age, max_valid, max_prefered;
2437 
2438                 if (ifp != ift->ifpub)
2439                         continue;
2440 
2441                 /* RFC 4941 section 3.3:
2442                  * If a received option will extend the lifetime of a public
2443                  * address, the lifetimes of temporary addresses should
2444                  * be extended, subject to the overall constraint that no
2445                  * temporary addresses should ever remain "valid" or "preferred"
2446                  * for a time longer than (TEMP_VALID_LIFETIME) or
2447                  * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR), respectively.
2448                  */
2449                 age = (now - ift->cstamp) / HZ;
2450                 max_valid = idev->cnf.temp_valid_lft - age;
2451                 if (max_valid < 0)
2452                         max_valid = 0;
2453 
2454                 max_prefered = idev->cnf.temp_prefered_lft -
2455                                idev->desync_factor - age;
2456                 if (max_prefered < 0)
2457                         max_prefered = 0;
2458 
2459                 if (valid_lft > max_valid)
2460                         valid_lft = max_valid;
2461 
2462                 if (prefered_lft > max_prefered)
2463                         prefered_lft = max_prefered;
2464 
2465                 spin_lock(&ift->lock);
2466                 flags = ift->flags;
2467                 ift->valid_lft = valid_lft;
2468                 ift->prefered_lft = prefered_lft;
2469                 ift->tstamp = now;
2470                 if (prefered_lft > 0)
2471                         ift->flags &= ~IFA_F_DEPRECATED;
2472 
2473                 spin_unlock(&ift->lock);
2474                 if (!(flags&IFA_F_TENTATIVE))
2475                         ipv6_ifa_notify(0, ift);
2476         }
2477 
2478         if ((create || list_empty(&idev->tempaddr_list)) &&
2479             idev->cnf.use_tempaddr > 0) {
2480                 /* When a new public address is created as described
2481                  * in [ADDRCONF], also create a new temporary address.
2482                  * Also create a temporary address if it's enabled but
2483                  * no temporary address currently exists.
2484                  */
2485                 read_unlock_bh(&idev->lock);
2486                 ipv6_create_tempaddr(ifp, NULL, false);
2487         } else {
2488                 read_unlock_bh(&idev->lock);
2489         }
2490 }
2491 
2492 static bool is_addr_mode_generate_stable(struct inet6_dev *idev)
2493 {
2494         return idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY ||
2495                idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_RANDOM;
2496 }
2497 
2498 int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
2499                                  const struct prefix_info *pinfo,
2500                                  struct inet6_dev *in6_dev,
2501                                  const struct in6_addr *addr, int addr_type,
2502                                  u32 addr_flags, bool sllao, bool tokenized,
2503                                  __u32 valid_lft, u32 prefered_lft)
2504 {
2505         struct inet6_ifaddr *ifp = ipv6_get_ifaddr(net, addr, dev, 1);
2506         int create = 0, update_lft = 0;
2507 
2508         if (!ifp && valid_lft) {
2509                 int max_addresses = in6_dev->cnf.max_addresses;
2510 
2511 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2512                 if ((net->ipv6.devconf_all->optimistic_dad ||
2513                      in6_dev->cnf.optimistic_dad) &&
2514                     !net->ipv6.devconf_all->forwarding && sllao)
2515                         addr_flags |= IFA_F_OPTIMISTIC;
2516 #endif
2517 
2518                 /* Do not allow to create too much of autoconfigured
2519                  * addresses; this would be too easy way to crash kernel.
2520                  */
2521                 if (!max_addresses ||
2522                     ipv6_count_addresses(in6_dev) < max_addresses)
2523                         ifp = ipv6_add_addr(in6_dev, addr, NULL,
2524                                             pinfo->prefix_len,
2525                                             addr_type&IPV6_ADDR_SCOPE_MASK,
2526                                             addr_flags, valid_lft,
2527                                             prefered_lft, false, NULL);
2528 
2529                 if (IS_ERR_OR_NULL(ifp))
2530                         return -1;
2531 
2532                 update_lft = 0;
2533                 create = 1;
2534                 spin_lock_bh(&ifp->lock);
2535                 ifp->flags |= IFA_F_MANAGETEMPADDR;
2536                 ifp->cstamp = jiffies;
2537                 ifp->tokenized = tokenized;
2538                 spin_unlock_bh(&ifp->lock);
2539                 addrconf_dad_start(ifp);
2540         }
2541 
2542         if (ifp) {
2543                 u32 flags;
2544                 unsigned long now;
2545                 u32 stored_lft;
2546 
2547                 /* update lifetime (RFC2462 5.5.3 e) */
2548                 spin_lock_bh(&ifp->lock);
2549                 now = jiffies;
2550                 if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2551                         stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2552                 else
2553                         stored_lft = 0;
2554                 if (!update_lft && !create && stored_lft) {
2555                         const u32 minimum_lft = min_t(u32,
2556                                 stored_lft, MIN_VALID_LIFETIME);
2557                         valid_lft = max(valid_lft, minimum_lft);
2558 
2559                         /* RFC4862 Section 5.5.3e:
2560                          * "Note that the preferred lifetime of the
2561                          *  corresponding address is always reset to
2562                          *  the Preferred Lifetime in the received
2563                          *  Prefix Information option, regardless of
2564                          *  whether the valid lifetime is also reset or
2565                          *  ignored."
2566                          *
2567                          * So we should always update prefered_lft here.
2568                          */
2569                         update_lft = 1;
2570                 }
2571 
2572                 if (update_lft) {
2573                         ifp->valid_lft = valid_lft;
2574                         ifp->prefered_lft = prefered_lft;
2575                         ifp->tstamp = now;
2576                         flags = ifp->flags;
2577                         ifp->flags &= ~IFA_F_DEPRECATED;
2578                         spin_unlock_bh(&ifp->lock);
2579 
2580                         if (!(flags&IFA_F_TENTATIVE))
2581                                 ipv6_ifa_notify(0, ifp);
2582                 } else
2583                         spin_unlock_bh(&ifp->lock);
2584 
2585                 manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
2586                                  create, now);
2587 
2588                 in6_ifa_put(ifp);
2589                 addrconf_verify();
2590         }
2591 
2592         return 0;
2593 }
2594 EXPORT_SYMBOL_GPL(addrconf_prefix_rcv_add_addr);
2595 
2596 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2597 {
2598         struct prefix_info *pinfo;
2599         __u32 valid_lft;
2600         __u32 prefered_lft;
2601         int addr_type, err;
2602         u32 addr_flags = 0;
2603         struct inet6_dev *in6_dev;
2604         struct net *net = dev_net(dev);
2605 
2606         pinfo = (struct prefix_info *) opt;
2607 
2608         if (len < sizeof(struct prefix_info)) {
2609                 netdev_dbg(dev, "addrconf: prefix option too short\n");
2610                 return;
2611         }
2612 
2613         /*
2614          *      Validation checks ([ADDRCONF], page 19)
2615          */
2616 
2617         addr_type = ipv6_addr_type(&pinfo->prefix);
2618 
2619         if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2620                 return;
2621 
2622         valid_lft = ntohl(pinfo->valid);
2623         prefered_lft = ntohl(pinfo->prefered);
2624 
2625         if (prefered_lft > valid_lft) {
2626                 net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2627                 return;
2628         }
2629 
2630         in6_dev = in6_dev_get(dev);
2631 
2632         if (!in6_dev) {
2633                 net_dbg_ratelimited("addrconf: device %s not configured\n",
2634                                     dev->name);
2635                 return;
2636         }
2637 
2638         /*
2639          *      Two things going on here:
2640          *      1) Add routes for on-link prefixes
2641          *      2) Configure prefixes with the auto flag set
2642          */
2643 
2644         if (pinfo->onlink) {
2645                 struct rt6_info *rt;
2646                 unsigned long rt_expires;
2647 
2648                 /* Avoid arithmetic overflow. Really, we could
2649                  * save rt_expires in seconds, likely valid_lft,
2650                  * but it would require division in fib gc, that it
2651                  * not good.
2652                  */
2653                 if (HZ > USER_HZ)
2654                         rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2655                 else
2656                         rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2657 
2658                 if (addrconf_finite_timeout(rt_expires))
2659                         rt_expires *= HZ;
2660 
2661                 rt = addrconf_get_prefix_route(&pinfo->prefix,
2662                                                pinfo->prefix_len,
2663                                                dev,
2664                                                RTF_ADDRCONF | RTF_PREFIX_RT,
2665                                                RTF_GATEWAY | RTF_DEFAULT);
2666 
2667                 if (rt) {
2668                         /* Autoconf prefix route */
2669                         if (valid_lft == 0) {
2670                                 ip6_del_rt(rt);
2671                                 rt = NULL;
2672                         } else if (addrconf_finite_timeout(rt_expires)) {
2673                                 /* not infinity */
2674                                 rt6_set_expires(rt, jiffies + rt_expires);
2675                         } else {
2676                                 rt6_clean_expires(rt);
2677                         }
2678                 } else if (valid_lft) {
2679                         clock_t expires = 0;
2680                         int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2681                         if (addrconf_finite_timeout(rt_expires)) {
2682                                 /* not infinity */
2683                                 flags |= RTF_EXPIRES;
2684                                 expires = jiffies_to_clock_t(rt_expires);
2685                         }
2686                         addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2687                                               dev, expires, flags);
2688                 }
2689                 ip6_rt_put(rt);
2690         }
2691 
2692         /* Try to figure out our local address for this prefix */
2693 
2694         if (pinfo->autoconf && in6_dev->cnf.autoconf) {
2695                 struct in6_addr addr;
2696                 bool tokenized = false, dev_addr_generated = false;
2697 
2698                 if (pinfo->prefix_len == 64) {
2699                         memcpy(&addr, &pinfo->prefix, 8);
2700 
2701                         if (!ipv6_addr_any(&in6_dev->token)) {
2702                                 read_lock_bh(&in6_dev->lock);
2703                                 memcpy(addr.s6_addr + 8,
2704                                        in6_dev->token.s6_addr + 8, 8);
2705                                 read_unlock_bh(&in6_dev->lock);
2706                                 tokenized = true;
2707                         } else if (is_addr_mode_generate_stable(in6_dev) &&
2708                                    !ipv6_generate_stable_address(&addr, 0,
2709                                                                  in6_dev)) {
2710                                 addr_flags |= IFA_F_STABLE_PRIVACY;
2711                                 goto ok;
2712                         } else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2713                                    ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2714                                 goto put;
2715                         } else {
2716                                 dev_addr_generated = true;
2717                         }
2718                         goto ok;
2719                 }
2720                 net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2721                                     pinfo->prefix_len);
2722                 goto put;
2723 
2724 ok:
2725                 err = addrconf_prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
2726                                                    &addr, addr_type,
2727                                                    addr_flags, sllao,
2728                                                    tokenized, valid_lft,
2729                                                    prefered_lft);
2730                 if (err)
2731                         goto put;
2732 
2733                 /* Ignore error case here because previous prefix add addr was
2734                  * successful which will be notified.
2735                  */
2736                 ndisc_ops_prefix_rcv_add_addr(net, dev, pinfo, in6_dev, &addr,
2737                                               addr_type, addr_flags, sllao,
2738                                               tokenized, valid_lft,
2739                                               prefered_lft,
2740                                               dev_addr_generated);
2741         }
2742         inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2743 put:
2744         in6_dev_put(in6_dev);
2745 }
2746 
2747 /*
2748  *      Set destination address.
2749  *      Special case for SIT interfaces where we create a new "virtual"
2750  *      device.
2751  */
2752 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2753 {
2754         struct in6_ifreq ireq;
2755         struct net_device *dev;
2756         int err = -EINVAL;
2757 
2758         rtnl_lock();
2759 
2760         err = -EFAULT;
2761         if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2762                 goto err_exit;
2763 
2764         dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2765 
2766         err = -ENODEV;
2767         if (!dev)
2768                 goto err_exit;
2769 
2770 #if IS_ENABLED(CONFIG_IPV6_SIT)
2771         if (dev->type == ARPHRD_SIT) {
2772                 const struct net_device_ops *ops = dev->netdev_ops;
2773                 struct ifreq ifr;
2774                 struct ip_tunnel_parm p;
2775 
2776                 err = -EADDRNOTAVAIL;
2777                 if (!(ipv6_addr_type(&ireq.ifr6_addr) & IPV6_ADDR_COMPATv4))
2778                         goto err_exit;
2779 
2780                 memset(&p, 0, sizeof(p));
2781                 p.iph.daddr = ireq.ifr6_addr.s6_addr32[3];
2782                 p.iph.saddr = 0;
2783                 p.iph.version = 4;
2784                 p.iph.ihl = 5;
2785                 p.iph.protocol = IPPROTO_IPV6;
2786                 p.iph.ttl = 64;
2787                 ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
2788 
2789                 if (ops->ndo_do_ioctl) {
2790                         mm_segment_t oldfs = get_fs();
2791 
2792                         set_fs(KERNEL_DS);
2793                         err = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
2794                         set_fs(oldfs);
2795                 } else
2796                         err = -EOPNOTSUPP;
2797 
2798                 if (err == 0) {
2799                         err = -ENOBUFS;
2800                         dev = __dev_get_by_name(net, p.name);
2801                         if (!dev)
2802                                 goto err_exit;
2803                         err = dev_open(dev);
2804                 }
2805         }
2806 #endif
2807 
2808 err_exit:
2809         rtnl_unlock();
2810         return err;
2811 }
2812 
2813 static int ipv6_mc_config(struct sock *sk, bool join,
2814                           const struct in6_addr *addr, int ifindex)
2815 {
2816         int ret;
2817 
2818         ASSERT_RTNL();
2819 
2820         lock_sock(sk);
2821         if (join)
2822                 ret = ipv6_sock_mc_join(sk, ifindex, addr);
2823         else
2824                 ret = ipv6_sock_mc_drop(sk, ifindex, addr);
2825         release_sock(sk);
2826 
2827         return ret;
2828 }
2829 
2830 /*
2831  *      Manual configuration of address on an interface
2832  */
2833 static int inet6_addr_add(struct net *net, int ifindex,
2834                           const struct in6_addr *pfx,
2835                           const struct in6_addr *peer_pfx,
2836                           unsigned int plen, __u32 ifa_flags,
2837                           __u32 prefered_lft, __u32 valid_lft,
2838                           struct netlink_ext_ack *extack)
2839 {
2840         struct inet6_ifaddr *ifp;
2841         struct inet6_dev *idev;
2842         struct net_device *dev;
2843         unsigned long timeout;
2844         clock_t expires;
2845         int scope;
2846         u32 flags;
2847 
2848         ASSERT_RTNL();
2849 
2850         if (plen > 128)
2851                 return -EINVAL;
2852 
2853         /* check the lifetime */
2854         if (!valid_lft || prefered_lft > valid_lft)
2855                 return -EINVAL;
2856 
2857         if (ifa_flags & IFA_F_MANAGETEMPADDR && plen != 64)
2858                 return -EINVAL;
2859 
2860         dev = __dev_get_by_index(net, ifindex);
2861         if (!dev)
2862                 return -ENODEV;
2863 
2864         idev = addrconf_add_dev(dev);
2865         if (IS_ERR(idev))
2866                 return PTR_ERR(idev);
2867 
2868         if (ifa_flags & IFA_F_MCAUTOJOIN) {
2869                 int ret = ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2870                                          true, pfx, ifindex);
2871 
2872                 if (ret < 0)
2873                         return ret;
2874         }
2875 
2876         scope = ipv6_addr_scope(pfx);
2877 
2878         timeout = addrconf_timeout_fixup(valid_lft, HZ);
2879         if (addrconf_finite_timeout(timeout)) {
2880                 expires = jiffies_to_clock_t(timeout * HZ);
2881                 valid_lft = timeout;
2882                 flags = RTF_EXPIRES;
2883         } else {
2884                 expires = 0;
2885                 flags = 0;
2886                 ifa_flags |= IFA_F_PERMANENT;
2887         }
2888 
2889         timeout = addrconf_timeout_fixup(prefered_lft, HZ);
2890         if (addrconf_finite_timeout(timeout)) {
2891                 if (timeout == 0)
2892                         ifa_flags |= IFA_F_DEPRECATED;
2893                 prefered_lft = timeout;
2894         }
2895 
2896         ifp = ipv6_add_addr(idev, pfx, peer_pfx, plen, scope, ifa_flags,
2897                             valid_lft, prefered_lft, true, extack);
2898 
2899         if (!IS_ERR(ifp)) {
2900                 if (!(ifa_flags & IFA_F_NOPREFIXROUTE)) {
2901                         addrconf_prefix_route(&ifp->addr, ifp->prefix_len, dev,
2902                                               expires, flags);
2903                 }
2904 
2905                 /*
2906                  * Note that section 3.1 of RFC 4429 indicates
2907                  * that the Optimistic flag should not be set for
2908                  * manually configured addresses
2909                  */
2910                 addrconf_dad_start(ifp);
2911                 if (ifa_flags & IFA_F_MANAGETEMPADDR)
2912                         manage_tempaddrs(idev, ifp, valid_lft, prefered_lft,
2913                                          true, jiffies);
2914                 in6_ifa_put(ifp);
2915                 addrconf_verify_rtnl();
2916                 return 0;
2917         } else if (ifa_flags & IFA_F_MCAUTOJOIN) {
2918                 ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2919                                false, pfx, ifindex);
2920         }
2921 
2922         return PTR_ERR(ifp);
2923 }
2924 
2925 static int inet6_addr_del(struct net *net, int ifindex, u32 ifa_flags,
2926                           const struct in6_addr *pfx, unsigned int plen)
2927 {
2928         struct inet6_ifaddr *ifp;
2929         struct inet6_dev *idev;
2930         struct net_device *dev;
2931 
2932         if (plen > 128)
2933                 return -EINVAL;
2934 
2935         dev = __dev_get_by_index(net, ifindex);
2936         if (!dev)
2937                 return -ENODEV;
2938 
2939         idev = __in6_dev_get(dev);
2940         if (!idev)
2941                 return -ENXIO;
2942 
2943         read_lock_bh(&idev->lock);
2944         list_for_each_entry(ifp, &idev->addr_list, if_list) {
2945                 if (ifp->prefix_len == plen &&
2946                     ipv6_addr_equal(pfx, &ifp->addr)) {
2947                         in6_ifa_hold(ifp);
2948                         read_unlock_bh(&idev->lock);
2949 
2950                         if (!(ifp->flags & IFA_F_TEMPORARY) &&
2951                             (ifa_flags & IFA_F_MANAGETEMPADDR))
2952                                 manage_tempaddrs(idev, ifp, 0, 0, false,
2953                                                  jiffies);
2954                         ipv6_del_addr(ifp);
2955                         addrconf_verify_rtnl();
2956                         if (ipv6_addr_is_multicast(pfx)) {
2957                                 ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2958                                                false, pfx, dev->ifindex);
2959                         }
2960                         return 0;
2961                 }
2962         }
2963         read_unlock_bh(&idev->lock);
2964         return -EADDRNOTAVAIL;
2965 }
2966 
2967 
2968 int addrconf_add_ifaddr(struct net *net, void __user *arg)
2969 {
2970         struct in6_ifreq ireq;
2971         int err;
2972 
2973         if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2974                 return -EPERM;
2975 
2976         if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2977                 return -EFAULT;
2978 
2979         rtnl_lock();
2980         err = inet6_addr_add(net, ireq.ifr6_ifindex, &ireq.ifr6_addr, NULL,
2981                              ireq.ifr6_prefixlen, IFA_F_PERMANENT,
2982                              INFINITY_LIFE_TIME, INFINITY_LIFE_TIME, NULL);
2983         rtnl_unlock();
2984         return err;
2985 }
2986 
2987 int addrconf_del_ifaddr(struct net *net, void __user *arg)
2988 {
2989         struct in6_ifreq ireq;
2990         int err;
2991 
2992         if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2993                 return -EPERM;
2994 
2995         if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2996                 return -EFAULT;
2997 
2998         rtnl_lock();
2999         err = inet6_addr_del(net, ireq.ifr6_ifindex, 0, &ireq.ifr6_addr,
3000                              ireq.ifr6_prefixlen);
3001         rtnl_unlock();
3002         return err;
3003 }
3004 
3005 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
3006                      int plen, int scope)
3007 {
3008         struct inet6_ifaddr *ifp;
3009 
3010         ifp = ipv6_add_addr(idev, addr, NULL, plen,
3011                             scope, IFA_F_PERMANENT,
3012                             INFINITY_LIFE_TIME, INFINITY_LIFE_TIME,
3013                             true, NULL);
3014         if (!IS_ERR(ifp)) {
3015                 spin_lock_bh(&ifp->lock);
3016                 ifp->flags &= ~IFA_F_TENTATIVE;
3017                 spin_unlock_bh(&ifp->lock);
3018                 rt_genid_bump_ipv6(dev_net(idev->dev));
3019                 ipv6_ifa_notify(RTM_NEWADDR, ifp);
3020                 in6_ifa_put(ifp);
3021         }
3022 }
3023 
3024 #if IS_ENABLED(CONFIG_IPV6_SIT)
3025 static void sit_add_v4_addrs(struct inet6_dev *idev)
3026 {
3027         struct in6_addr addr;
3028         struct net_device *dev;
3029         struct net *net = dev_net(idev->dev);
3030         int scope, plen;
3031         u32 pflags = 0;
3032 
3033         ASSERT_RTNL();
3034 
3035         memset(&addr, 0, sizeof(struct in6_addr));
3036         memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
3037 
3038         if (idev->dev->flags&IFF_POINTOPOINT) {
3039                 addr.s6_addr32[0] = htonl(0xfe800000);
3040                 scope = IFA_LINK;
3041                 plen = 64;
3042         } else {
3043                 scope = IPV6_ADDR_COMPATv4;
3044                 plen = 96;
3045                 pflags |= RTF_NONEXTHOP;
3046         }
3047 
3048         if (addr.s6_addr32[3]) {
3049                 add_addr(idev, &addr, plen, scope);
3050                 addrconf_prefix_route(&addr, plen, idev->dev, 0, pflags);
3051                 return;
3052         }
3053 
3054         for_each_netdev(net, dev) {
3055                 struct in_device *in_dev = __in_dev_get_rtnl(dev);
3056                 if (in_dev && (dev->flags & IFF_UP)) {
3057                         struct in_ifaddr *ifa;
3058 
3059                         int flag = scope;
3060 
3061                         for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
3062 
3063                                 addr.s6_addr32[3] = ifa->ifa_local;
3064 
3065                                 if (ifa->ifa_scope == RT_SCOPE_LINK)
3066                                         continue;
3067                                 if (ifa->ifa_scope >= RT_SCOPE_HOST) {
3068                                         if (idev->dev->flags&IFF_POINTOPOINT)
3069                                                 continue;
3070                                         flag |= IFA_HOST;
3071                                 }
3072 
3073                                 add_addr(idev, &addr, plen, flag);
3074                                 addrconf_prefix_route(&addr, plen, idev->dev, 0,
3075                                                       pflags);
3076                         }
3077                 }
3078         }
3079 }
3080 #endif
3081 
3082 static void init_loopback(struct net_device *dev)
3083 {
3084         struct inet6_dev  *idev;
3085 
3086         /* ::1 */
3087 
3088         ASSERT_RTNL();
3089 
3090         idev = ipv6_find_idev(dev);
3091         if (!idev) {
3092                 pr_debug("%s: add_dev failed\n", __func__);
3093                 return;
3094         }
3095 
3096         add_addr(idev, &in6addr_loopback, 128, IFA_HOST);
3097 }
3098 
3099 void addrconf_add_linklocal(struct inet6_dev *idev,
3100                             const struct in6_addr *addr, u32 flags)
3101 {
3102         struct inet6_ifaddr *ifp;
3103         u32 addr_flags = flags | IFA_F_PERMANENT;
3104 
3105 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
3106         if ((dev_net(idev->dev)->ipv6.devconf_all->optimistic_dad ||
3107              idev->cnf.optimistic_dad) &&
3108             !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
3109                 addr_flags |= IFA_F_OPTIMISTIC;
3110 #endif
3111 
3112         ifp = ipv6_add_addr(idev, addr, NULL, 64, IFA_LINK, addr_flags,
3113                             INFINITY_LIFE_TIME, INFINITY_LIFE_TIME, true, NULL);
3114         if (!IS_ERR(ifp)) {
3115                 addrconf_prefix_route(&ifp->addr, ifp->prefix_len, idev->dev, 0, 0);
3116                 addrconf_dad_start(ifp);
3117                 in6_ifa_put(ifp);
3118         }
3119 }
3120 EXPORT_SYMBOL_GPL(addrconf_add_linklocal);
3121 
3122 static bool ipv6_reserved_interfaceid(struct in6_addr address)
3123 {
3124         if ((address.s6_addr32[2] | address.s6_addr32[3]) == 0)
3125                 return true;
3126 
3127         if (address.s6_addr32[2] == htonl(0x02005eff) &&
3128             ((address.s6_addr32[3] & htonl(0xfe000000)) == htonl(0xfe000000)))
3129                 return true;
3130 
3131         if (address.s6_addr32[2] == htonl(0xfdffffff) &&
3132             ((address.s6_addr32[3] & htonl(0xffffff80)) == htonl(0xffffff80)))
3133                 return true;
3134 
3135         return false;
3136 }
3137 
3138 static int ipv6_generate_stable_address(struct in6_addr *address,
3139                                         u8 dad_count,
3140                                         const struct inet6_dev *idev)
3141 {
3142         static DEFINE_SPINLOCK(lock);
3143         static __u32 digest[SHA_DIGEST_WORDS];
3144         static __u32 workspace[SHA_WORKSPACE_WORDS];
3145 
3146         static union {
3147                 char __data[SHA_MESSAGE_BYTES];
3148                 struct {
3149                         struct in6_addr secret;
3150                         __be32 prefix[2];
3151                         unsigned char hwaddr[MAX_ADDR_LEN];
3152                         u8 dad_count;
3153                 } __packed;
3154         } data;
3155 
3156         struct in6_addr secret;
3157         struct in6_addr temp;
3158         struct net *net = dev_net(idev->dev);
3159 
3160         BUILD_BUG_ON(sizeof(data.__data) != sizeof(data));
3161 
3162         if (idev->cnf.stable_secret.initialized)
3163                 secret = idev->cnf.stable_secret.secret;
3164         else if (net->ipv6.devconf_dflt->stable_secret.initialized)
3165                 secret = net->ipv6.devconf_dflt->stable_secret.secret;
3166         else
3167                 return -1;
3168 
3169 retry:
3170         spin_lock_bh(&lock);
3171 
3172         sha_init(digest);
3173         memset(&data, 0, sizeof(data));
3174         memset(workspace, 0, sizeof(workspace));
3175         memcpy(data.hwaddr, idev->dev->perm_addr, idev->dev->addr_len);
3176         data.prefix[0] = address->s6_addr32[0];
3177         data.prefix[1] = address->s6_addr32[1];
3178         data.secret = secret;
3179         data.dad_count = dad_count;
3180 
3181         sha_transform(digest, data.__data, workspace);
3182 
3183         temp = *address;
3184         temp.s6_addr32[2] = (__force __be32)digest[0];
3185         temp.s6_addr32[3] = (__force __be32)digest[1];
3186 
3187         spin_unlock_bh(&lock);
3188 
3189         if (ipv6_reserved_interfaceid(temp)) {
3190                 dad_count++;
3191                 if (dad_count > dev_net(idev->dev)->ipv6.sysctl.idgen_retries)
3192                         return -1;
3193                 goto retry;
3194         }
3195 
3196         *address = temp;
3197         return 0;
3198 }
3199 
3200 static void ipv6_gen_mode_random_init(struct inet6_dev *idev)
3201 {
3202         struct ipv6_stable_secret *s = &idev->cnf.stable_secret;
3203 
3204         if (s->initialized)
3205                 return;
3206         s = &idev->cnf.stable_secret;
3207         get_random_bytes(&s->secret, sizeof(s->secret));
3208         s->initialized = true;
3209 }
3210 
3211 static void addrconf_addr_gen(struct inet6_dev *idev, bool prefix_route)
3212 {
3213         struct in6_addr addr;
3214 
3215         /* no link local addresses on L3 master devices */
3216         if (netif_is_l3_master(idev->dev))
3217                 return;
3218 
3219         ipv6_addr_set(&addr, htonl(0xFE800000), 0, 0, 0);
3220 
3221         switch (idev->cnf.addr_gen_mode) {
3222         case IN6_ADDR_GEN_MODE_RANDOM:
3223                 ipv6_gen_mode_random_init(idev);
3224                 /* fallthrough */
3225         case IN6_ADDR_GEN_MODE_STABLE_PRIVACY:
3226                 if (!ipv6_generate_stable_address(&addr, 0, idev))
3227                         addrconf_add_linklocal(idev, &addr,
3228                                                IFA_F_STABLE_PRIVACY);
3229                 else if (prefix_route)
3230                         addrconf_prefix_route(&addr, 64, idev->dev, 0, 0);
3231                 break;
3232         case IN6_ADDR_GEN_MODE_EUI64:
3233                 /* addrconf_add_linklocal also adds a prefix_route and we
3234                  * only need to care about prefix routes if ipv6_generate_eui64
3235                  * couldn't generate one.
3236                  */
3237                 if (ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) == 0)
3238                         addrconf_add_linklocal(idev, &addr, 0);
3239                 else if (prefix_route)
3240                         addrconf_prefix_route(&addr, 64, idev->dev, 0, 0);
3241                 break;
3242         case IN6_ADDR_GEN_MODE_NONE:
3243         default:
3244                 /* will not add any link local address */
3245                 break;
3246         }
3247 }
3248 
3249 static void addrconf_dev_config(struct net_device *dev)
3250 {
3251         struct inet6_dev *idev;
3252 
3253         ASSERT_RTNL();
3254 
3255         if ((dev->type != ARPHRD_ETHER) &&
3256             (dev->type != ARPHRD_FDDI) &&
3257             (dev->type != ARPHRD_ARCNET) &&
3258             (dev->type != ARPHRD_INFINIBAND) &&
3259             (dev->type != ARPHRD_IEEE1394) &&
3260             (dev->type != ARPHRD_TUNNEL6) &&
3261             (dev->type != ARPHRD_6LOWPAN) &&
3262             (dev->type != ARPHRD_IP6GRE) &&
3263             (dev->type != ARPHRD_IPGRE) &&
3264             (dev->type != ARPHRD_TUNNEL) &&
3265             (dev->type != ARPHRD_NONE)) {
3266                 /* Alas, we support only Ethernet autoconfiguration. */
3267                 return;
3268         }
3269 
3270         idev = addrconf_add_dev(dev);
3271         if (IS_ERR(idev))
3272                 return;
3273 
3274         /* this device type has no EUI support */
3275         if (dev->type == ARPHRD_NONE &&
3276             idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64)
3277                 idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_RANDOM;
3278 
3279         addrconf_addr_gen(idev, false);
3280 }
3281 
3282 #if IS_ENABLED(CONFIG_IPV6_SIT)
3283 static void addrconf_sit_config(struct net_device *dev)
3284 {
3285         struct inet6_dev *idev;
3286 
3287         ASSERT_RTNL();
3288 
3289         /*
3290          * Configure the tunnel with one of our IPv4
3291          * addresses... we should configure all of
3292          * our v4 addrs in the tunnel
3293          */
3294 
3295         idev = ipv6_find_idev(dev);
3296         if (!idev) {
3297                 pr_debug("%s: add_dev failed\n", __func__);
3298                 return;
3299         }
3300 
3301         if (dev->priv_flags & IFF_ISATAP) {
3302                 addrconf_addr_gen(idev, false);
3303                 return;
3304         }
3305 
3306         sit_add_v4_addrs(idev);
3307 
3308         if (dev->flags&IFF_POINTOPOINT)
3309                 addrconf_add_mroute(dev);
3310 }
3311 #endif
3312 
3313 #if IS_ENABLED(CONFIG_NET_IPGRE)
3314 static void addrconf_gre_config(struct net_device *dev)
3315 {
3316         struct inet6_dev *idev;
3317 
3318         ASSERT_RTNL();
3319 
3320         idev = ipv6_find_idev(dev);
3321         if (!idev) {
3322                 pr_debug("%s: add_dev failed\n", __func__);
3323                 return;
3324         }
3325 
3326         addrconf_addr_gen(idev, true);
3327         if (dev->flags & IFF_POINTOPOINT)
3328                 addrconf_add_mroute(dev);
3329 }
3330 #endif
3331 
3332 static int fixup_permanent_addr(struct inet6_dev *idev,
3333                                 struct inet6_ifaddr *ifp)
3334 {
3335         /* !rt6i_node means the host route was removed from the
3336          * FIB, for example, if 'lo' device is taken down. In that
3337          * case regenerate the host route.
3338          */
3339         if (!ifp->rt || !ifp->rt->rt6i_node) {
3340                 struct rt6_info *rt, *prev;
3341 
3342                 rt = addrconf_dst_alloc(idev, &ifp->addr, false);
3343                 if (IS_ERR(rt))
3344                         return PTR_ERR(rt);
3345 
3346                 /* ifp->rt can be accessed outside of rtnl */
3347                 spin_lock(&ifp->lock);
3348                 prev = ifp->rt;
3349                 ifp->rt = rt;
3350                 spin_unlock(&ifp->lock);
3351 
3352                 ip6_rt_put(prev);
3353         }
3354 
3355         if (!(ifp->flags & IFA_F_NOPREFIXROUTE)) {
3356                 addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3357                                       idev->dev, 0, 0);
3358         }
3359 
3360         if (ifp->state == INET6_IFADDR_STATE_PREDAD)
3361                 addrconf_dad_start(ifp);
3362 
3363         return 0;
3364 }
3365 
3366 static void addrconf_permanent_addr(struct net_device *dev)
3367 {
3368         struct inet6_ifaddr *ifp, *tmp;
3369         struct inet6_dev *idev;
3370 
3371         idev = __in6_dev_get(dev);
3372         if (!idev)
3373                 return;
3374 
3375         write_lock_bh(&idev->lock);
3376 
3377         list_for_each_entry_safe(ifp, tmp, &idev->addr_list, if_list) {
3378                 if ((ifp->flags & IFA_F_PERMANENT) &&
3379                     fixup_permanent_addr(idev, ifp) < 0) {
3380                         write_unlock_bh(&idev->lock);
3381                         in6_ifa_hold(ifp);
3382                         ipv6_del_addr(ifp);
3383                         write_lock_bh(&idev->lock);
3384 
3385                         net_info_ratelimited("%s: Failed to add prefix route for address %pI6c; dropping\n",
3386                                              idev->dev->name, &ifp->addr);
3387                 }
3388         }
3389 
3390         write_unlock_bh(&idev->lock);
3391 }
3392 
3393 static int addrconf_notify(struct notifier_block *this, unsigned long event,
3394                            void *ptr)
3395 {
3396         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3397         struct netdev_notifier_changeupper_info *info;
3398         struct inet6_dev *idev = __in6_dev_get(dev);
3399         struct net *net = dev_net(dev);
3400         int run_pending = 0;
3401         int err;
3402 
3403         switch (event) {
3404         case NETDEV_REGISTER:
3405                 if (!idev && dev->mtu >= IPV6_MIN_MTU) {
3406                         idev = ipv6_add_dev(dev);
3407                         if (IS_ERR(idev))
3408                                 return notifier_from_errno(PTR_ERR(idev));
3409                 }
3410                 break;
3411 
3412         case NETDEV_CHANGEMTU:
3413                 /* if MTU under IPV6_MIN_MTU stop IPv6 on this interface. */
3414                 if (dev->mtu < IPV6_MIN_MTU) {
3415                         addrconf_ifdown(dev, dev != net->loopback_dev);
3416                         break;
3417                 }
3418 
3419                 if (idev) {
3420                         rt6_mtu_change(dev, dev->mtu);
3421                         idev->cnf.mtu6 = dev->mtu;
3422                         break;
3423                 }
3424 
3425                 /* allocate new idev */
3426                 idev = ipv6_add_dev(dev);
3427                 if (IS_ERR(idev))
3428                         break;
3429 
3430                 /* device is still not ready */
3431                 if (!(idev->if_flags & IF_READY))
3432                         break;
3433 
3434                 run_pending = 1;
3435 
3436                 /* fall through */
3437 
3438         case NETDEV_UP:
3439         case NETDEV_CHANGE:
3440                 if (dev->flags & IFF_SLAVE)
3441                         break;
3442 
3443                 if (idev && idev->cnf.disable_ipv6)
3444                         break;
3445 
3446                 if (event == NETDEV_UP) {
3447                         /* restore routes for permanent addresses */
3448                         addrconf_permanent_addr(dev);
3449 
3450                         if (!addrconf_link_ready(dev)) {
3451                                 /* device is not ready yet. */
3452                                 pr_info("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
3453                                         dev->name);
3454                                 break;
3455                         }
3456 
3457                         if (!idev && dev->mtu >= IPV6_MIN_MTU)
3458                                 idev = ipv6_add_dev(dev);
3459 
3460                         if (!IS_ERR_OR_NULL(idev)) {
3461                                 idev->if_flags |= IF_READY;
3462                                 run_pending = 1;
3463                         }
3464                 } else if (event == NETDEV_CHANGE) {
3465                         if (!addrconf_link_ready(dev)) {
3466                                 /* device is still not ready. */
3467                                 rt6_sync_down_dev(dev, event);
3468                                 break;
3469                         }
3470 
3471                         if (idev) {
3472                                 if (idev->if_flags & IF_READY) {
3473                                         /* device is already configured -
3474                                          * but resend MLD reports, we might
3475                                          * have roamed and need to update
3476                                          * multicast snooping switches
3477                                          */
3478                                         ipv6_mc_up(idev);
3479                                         rt6_sync_up(dev, RTNH_F_LINKDOWN);
3480                                         break;
3481                                 }
3482                                 idev->if_flags |= IF_READY;
3483                         }
3484 
3485                         pr_info("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
3486                                 dev->name);
3487 
3488                         run_pending = 1;
3489                 }
3490 
3491                 switch (dev->type) {
3492 #if IS_ENABLED(CONFIG_IPV6_SIT)
3493                 case ARPHRD_SIT:
3494                         addrconf_sit_config(dev);
3495                         break;
3496 #endif
3497 #if IS_ENABLED(CONFIG_NET_IPGRE)
3498                 case ARPHRD_IPGRE:
3499                         addrconf_gre_config(dev);
3500                         break;
3501 #endif
3502                 case ARPHRD_LOOPBACK:
3503                         init_loopback(dev);
3504                         break;
3505 
3506                 default:
3507                         addrconf_dev_config(dev);
3508                         break;
3509                 }
3510 
3511                 if (!IS_ERR_OR_NULL(idev)) {
3512                         if (run_pending)
3513                                 addrconf_dad_run(idev);
3514 
3515                         /* Device has an address by now */
3516                         rt6_sync_up(dev, RTNH_F_DEAD);
3517 
3518                         /*
3519                          * If the MTU changed during the interface down,
3520                          * when the interface up, the changed MTU must be
3521                          * reflected in the idev as well as routers.
3522                          */
3523                         if (idev->cnf.mtu6 != dev->mtu &&
3524                             dev->mtu >= IPV6_MIN_MTU) {
3525                                 rt6_mtu_change(dev, dev->mtu);
3526                                 idev->cnf.mtu6 = dev->mtu;
3527                         }
3528                         idev->tstamp = jiffies;
3529                         inet6_ifinfo_notify(RTM_NEWLINK, idev);
3530 
3531                         /*
3532                          * If the changed mtu during down is lower than
3533                          * IPV6_MIN_MTU stop IPv6 on this interface.
3534                          */
3535                         if (dev->mtu < IPV6_MIN_MTU)
3536                                 addrconf_ifdown(dev, dev != net->loopback_dev);
3537                 }
3538                 break;
3539 
3540         case NETDEV_DOWN:
3541         case NETDEV_UNREGISTER:
3542                 /*
3543                  *      Remove all addresses from this interface.
3544                  */
3545                 addrconf_ifdown(dev, event != NETDEV_DOWN);
3546                 break;
3547 
3548         case NETDEV_CHANGENAME:
3549                 if (idev) {
3550                         snmp6_unregister_dev(idev);
3551                         addrconf_sysctl_unregister(idev);
3552                         err = addrconf_sysctl_register(idev);
3553                         if (err)
3554                                 return notifier_from_errno(err);
3555                         err = snmp6_register_dev(idev);
3556                         if (err) {
3557                                 addrconf_sysctl_unregister(idev);
3558                                 return notifier_from_errno(err);
3559                         }
3560                 }
3561                 break;
3562 
3563         case NETDEV_PRE_TYPE_CHANGE:
3564         case NETDEV_POST_TYPE_CHANGE:
3565                 if (idev)
3566                         addrconf_type_change(dev, event);
3567                 break;
3568 
3569         case NETDEV_CHANGEUPPER:
3570                 info = ptr;
3571 
3572                 /* flush all routes if dev is linked to or unlinked from
3573                  * an L3 master device (e.g., VRF)
3574                  */
3575                 if (info->upper_dev && netif_is_l3_master(info->upper_dev))
3576                         addrconf_ifdown(dev, 0);
3577         }
3578 
3579         return NOTIFY_OK;
3580 }
3581 
3582 /*
3583  *      addrconf module should be notified of a device going up
3584  */
3585 static struct notifier_block ipv6_dev_notf = {
3586         .notifier_call = addrconf_notify,
3587         .priority = ADDRCONF_NOTIFY_PRIORITY,
3588 };
3589 
3590 static void addrconf_type_change(struct net_device *dev, unsigned long event)
3591 {
3592         struct inet6_dev *idev;
3593         ASSERT_RTNL();
3594 
3595         idev = __in6_dev_get(dev);
3596 
3597         if (event == NETDEV_POST_TYPE_CHANGE)
3598                 ipv6_mc_remap(idev);
3599         else if (event == NETDEV_PRE_TYPE_CHANGE)
3600                 ipv6_mc_unmap(idev);
3601 }
3602 
3603 static bool addr_is_local(const struct in6_addr *addr)
3604 {
3605         return ipv6_addr_type(addr) &
3606                 (IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
3607 }
3608 
3609 static int addrconf_ifdown(struct net_device *dev, int how)
3610 {
3611         unsigned long event = how ? NETDEV_UNREGISTER : NETDEV_DOWN;
3612         struct net *net = dev_net(dev);
3613         struct inet6_dev *idev;
3614         struct inet6_ifaddr *ifa, *tmp;
3615         int _keep_addr;
3616         bool keep_addr;
3617         int state, i;
3618 
3619         ASSERT_RTNL();
3620 
3621         rt6_disable_ip(dev, event);
3622 
3623         idev = __in6_dev_get(dev);
3624         if (!idev)
3625                 return -ENODEV;
3626 
3627         /*
3628          * Step 1: remove reference to ipv6 device from parent device.
3629          *         Do not dev_put!
3630          */
3631         if (how) {
3632                 idev->dead = 1;
3633 
3634                 /* protected by rtnl_lock */
3635                 RCU_INIT_POINTER(dev->ip6_ptr, NULL);
3636 
3637                 /* Step 1.5: remove snmp6 entry */
3638                 snmp6_unregister_dev(idev);
3639 
3640         }
3641 
3642         /* aggregate the system setting and interface setting */
3643         _keep_addr = net->ipv6.devconf_all->keep_addr_on_down;
3644         if (!_keep_addr)
3645                 _keep_addr = idev->cnf.keep_addr_on_down;
3646 
3647         /* combine the user config with event to determine if permanent
3648          * addresses are to be removed from address hash table
3649          */
3650         keep_addr = !(how || _keep_addr <= 0 || idev->cnf.disable_ipv6);
3651 
3652         /* Step 2: clear hash table */
3653         for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3654                 struct hlist_head *h = &inet6_addr_lst[i];
3655 
3656                 spin_lock_bh(&addrconf_hash_lock);
3657 restart:
3658                 hlist_for_each_entry_rcu(ifa, h, addr_lst) {
3659                         if (ifa->idev == idev) {
3660                                 addrconf_del_dad_work(ifa);
3661                                 /* combined flag + permanent flag decide if
3662                                  * address is retained on a down event
3663                                  */
3664                                 if (!keep_addr ||
3665                                     !(ifa->flags & IFA_F_PERMANENT) ||
3666                                     addr_is_local(&ifa->addr)) {
3667                                         hlist_del_init_rcu(&ifa->addr_lst);
3668                                         goto restart;
3669                                 }
3670                         }
3671                 }
3672                 spin_unlock_bh(&addrconf_hash_lock);
3673         }
3674 
3675         write_lock_bh(&idev->lock);
3676 
3677         addrconf_del_rs_timer(idev);
3678 
3679         /* Step 2: clear flags for stateless addrconf */
3680         if (!how)
3681                 idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3682 
3683         /* Step 3: clear tempaddr list */
3684         while (!list_empty(&idev->tempaddr_list)) {
3685                 ifa = list_first_entry(&idev->tempaddr_list,
3686                                        struct inet6_ifaddr, tmp_list);
3687                 list_del(&ifa->tmp_list);
3688                 write_unlock_bh(&idev->lock);
3689                 spin_lock_bh(&ifa->lock);
3690 
3691                 if (ifa->ifpub) {
3692                         in6_ifa_put(ifa->ifpub);
3693                         ifa->ifpub = NULL;
3694                 }
3695                 spin_unlock_bh(&ifa->lock);
3696                 in6_ifa_put(ifa);
3697                 write_lock_bh(&idev->lock);
3698         }
3699 
3700         /* re-combine the user config with event to determine if permanent
3701          * addresses are to be removed from the interface list
3702          */
3703         keep_addr = (!how && _keep_addr > 0 && !idev->cnf.disable_ipv6);
3704 
3705         list_for_each_entry_safe(ifa, tmp, &idev->addr_list, if_list) {
3706                 struct rt6_info *rt = NULL;
3707                 bool keep;
3708 
3709                 addrconf_del_dad_work(ifa);
3710 
3711                 keep = keep_addr && (ifa->flags & IFA_F_PERMANENT) &&
3712                         !addr_is_local(&ifa->addr);
3713 
3714                 write_unlock_bh(&idev->lock);
3715                 spin_lock_bh(&ifa->lock);
3716 
3717                 if (keep) {
3718                         /* set state to skip the notifier below */
3719                         state = INET6_IFADDR_STATE_DEAD;
3720                         ifa->state = INET6_IFADDR_STATE_PREDAD;
3721                         if (!(ifa->flags & IFA_F_NODAD))
3722                                 ifa->flags |= IFA_F_TENTATIVE;
3723 
3724                         rt = ifa->rt;
3725                         ifa->rt = NULL;
3726                 } else {
3727                         state = ifa->state;
3728                         ifa->state = INET6_IFADDR_STATE_DEAD;
3729                 }
3730 
3731                 spin_unlock_bh(&ifa->lock);
3732 
3733                 if (rt)
3734                         ip6_del_rt(rt);
3735 
3736                 if (state != INET6_IFADDR_STATE_DEAD) {
3737                         __ipv6_ifa_notify(RTM_DELADDR, ifa);
3738                         inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
3739                 } else {
3740                         if (idev->cnf.forwarding)
3741                                 addrconf_leave_anycast(ifa);
3742                         addrconf_leave_solict(ifa->idev, &ifa->addr);
3743                 }
3744 
3745                 write_lock_bh(&idev->lock);
3746                 if (!keep) {
3747                         list_del_rcu(&ifa->if_list);
3748                         in6_ifa_put(ifa);
3749                 }
3750         }
3751 
3752         write_unlock_bh(&idev->lock);
3753 
3754         /* Step 5: Discard anycast and multicast list */
3755         if (how) {
3756                 ipv6_ac_destroy_dev(idev);
3757                 ipv6_mc_destroy_dev(idev);
3758         } else {
3759                 ipv6_mc_down(idev);
3760         }
3761 
3762         idev->tstamp = jiffies;
3763 
3764         /* Last: Shot the device (if unregistered) */
3765         if (how) {
3766                 addrconf_sysctl_unregister(idev);
3767                 neigh_parms_release(&nd_tbl, idev->nd_parms);
3768                 neigh_ifdown(&nd_tbl, dev);
3769                 in6_dev_put(idev);
3770         }
3771         return 0;
3772 }
3773 
3774 static void addrconf_rs_timer(struct timer_list *t)
3775 {
3776         struct inet6_dev *idev = from_timer(idev, t, rs_timer);
3777         struct net_device *dev = idev->dev;
3778         struct in6_addr lladdr;
3779 
3780         write_lock(&idev->lock);
3781         if (idev->dead || !(idev->if_flags & IF_READY))
3782                 goto out;
3783 
3784         if (!ipv6_accept_ra(idev))
3785                 goto out;
3786 
3787         /* Announcement received after solicitation was sent */
3788         if (idev->if_flags & IF_RA_RCVD)
3789                 goto out;
3790 
3791         if (idev->rs_probes++ < idev->cnf.rtr_solicits || idev->cnf.rtr_solicits < 0) {
3792                 write_unlock(&idev->lock);
3793                 if (!ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
3794                         ndisc_send_rs(dev, &lladdr,
3795                                       &in6addr_linklocal_allrouters);
3796                 else
3797                         goto put;
3798 
3799                 write_lock(&idev->lock);
3800                 idev->rs_interval = rfc3315_s14_backoff_update(
3801                         idev->rs_interval, idev->cnf.rtr_solicit_max_interval);
3802                 /* The wait after the last probe can be shorter */
3803                 addrconf_mod_rs_timer(idev, (idev->rs_probes ==
3804                                              idev->cnf.rtr_solicits) ?
3805                                       idev->cnf.rtr_solicit_delay :
3806                                       idev->rs_interval);
3807         } else {
3808                 /*
3809                  * Note: we do not support deprecated "all on-link"
3810                  * assumption any longer.
3811                  */
3812                 pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
3813         }
3814 
3815 out:
3816         write_unlock(&idev->lock);
3817 put:
3818         in6_dev_put(idev);
3819 }
3820 
3821 /*
3822  *      Duplicate Address Detection
3823  */
3824 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
3825 {
3826         unsigned long rand_num;
3827         struct inet6_dev *idev = ifp->idev;
3828         u64 nonce;
3829 
3830         if (ifp->flags & IFA_F_OPTIMISTIC)
3831                 rand_num = 0;
3832         else
3833                 rand_num = prandom_u32() % (idev->cnf.rtr_solicit_delay ? : 1);
3834 
3835         nonce = 0;
3836         if (idev->cnf.enhanced_dad ||
3837             dev_net(idev->dev)->ipv6.devconf_all->enhanced_dad) {
3838                 do
3839                         get_random_bytes(&nonce, 6);
3840                 while (nonce == 0);
3841         }
3842         ifp->dad_nonce = nonce;
3843         ifp->dad_probes = idev->cnf.dad_transmits;
3844         addrconf_mod_dad_work(ifp, rand_num);
3845 }
3846 
3847 static void addrconf_dad_begin(struct inet6_ifaddr *ifp)
3848 {
3849         struct inet6_dev *idev = ifp->idev;
3850         struct net_device *dev = idev->dev;
3851         bool bump_id, notify = false;
3852 
3853         addrconf_join_solict(dev, &ifp->addr);
3854 
3855         prandom_seed((__force u32) ifp->addr.s6_addr32[3]);
3856 
3857         read_lock_bh(&idev->lock);
3858         spin_lock(&ifp->lock);
3859         if (ifp->state == INET6_IFADDR_STATE_DEAD)
3860                 goto out;
3861 
3862         if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
3863             (dev_net(dev)->ipv6.devconf_all->accept_dad < 1 &&
3864              idev->cnf.accept_dad < 1) ||
3865             !(ifp->flags&IFA_F_TENTATIVE) ||
3866             ifp->flags & IFA_F_NODAD) {
3867                 bool send_na = false;
3868 
3869                 if (ifp->flags & IFA_F_TENTATIVE &&
3870                     !(ifp->flags & IFA_F_OPTIMISTIC))
3871                         send_na = true;
3872                 bump_id = ifp->flags & IFA_F_TENTATIVE;
3873                 ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3874                 spin_unlock(&ifp->lock);
3875                 read_unlock_bh(&idev->lock);
3876 
3877                 addrconf_dad_completed(ifp, bump_id, send_na);
3878                 return;
3879         }
3880 
3881         if (!(idev->if_flags & IF_READY)) {
3882                 spin_unlock(&ifp->lock);
3883                 read_unlock_bh(&idev->lock);
3884                 /*
3885                  * If the device is not ready:
3886                  * - keep it tentative if it is a permanent address.
3887                  * - otherwise, kill it.
3888                  */
3889                 in6_ifa_hold(ifp);
3890                 addrconf_dad_stop(ifp, 0);
3891                 return;
3892         }
3893 
3894         /*
3895          * Optimistic nodes can start receiving
3896          * Frames right away
3897          */
3898         if (ifp->flags & IFA_F_OPTIMISTIC) {
3899                 ip6_ins_rt(ifp->rt);
3900                 if (ipv6_use_optimistic_addr(dev_net(dev), idev)) {
3901                         /* Because optimistic nodes can use this address,
3902                          * notify listeners. If DAD fails, RTM_DELADDR is sent.
3903                          */
3904                         notify = true;
3905                 }
3906         }
3907 
3908         addrconf_dad_kick(ifp);
3909 out:
3910         spin_unlock(&ifp->lock);
3911         read_unlock_bh(&idev->lock);
3912         if (notify)
3913                 ipv6_ifa_notify(RTM_NEWADDR, ifp);
3914 }
3915 
3916 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
3917 {
3918         bool begin_dad = false;
3919 
3920         spin_lock_bh(&ifp->lock);
3921         if (ifp->state != INET6_IFADDR_STATE_DEAD) {
3922                 ifp->state = INET6_IFADDR_STATE_PREDAD;
3923                 begin_dad = true;
3924         }
3925         spin_unlock_bh(&ifp->lock);
3926 
3927         if (begin_dad)
3928                 addrconf_mod_dad_work(ifp, 0);
3929 }
3930 
3931 static void addrconf_dad_work(struct work_struct *w)
3932 {
3933         struct inet6_ifaddr *ifp = container_of(to_delayed_work(w),
3934                                                 struct inet6_ifaddr,
3935                                                 dad_work);
3936         struct inet6_dev *idev = ifp->idev;
3937         bool bump_id, disable_ipv6 = false;
3938         struct in6_addr mcaddr;
3939 
3940         enum {
3941                 DAD_PROCESS,
3942                 DAD_BEGIN,
3943                 DAD_ABORT,
3944         } action = DAD_PROCESS;
3945 
3946         rtnl_lock();
3947 
3948         spin_lock_bh(&ifp->lock);
3949         if (ifp->state == INET6_IFADDR_STATE_PREDAD) {
3950                 action = DAD_BEGIN;
3951                 ifp->state = INET6_IFADDR_STATE_DAD;
3952         } else if (ifp->state == INET6_IFADDR_STATE_ERRDAD) {
3953                 action = DAD_ABORT;
3954                 ifp->state = INET6_IFADDR_STATE_POSTDAD;
3955 
3956                 if ((dev_net(idev->dev)->ipv6.devconf_all->accept_dad > 1 ||
3957                      idev->cnf.accept_dad > 1) &&
3958                     !idev->cnf.disable_ipv6 &&
3959                     !(ifp->flags & IFA_F_STABLE_PRIVACY)) {
3960                         struct in6_addr addr;
3961 
3962                         addr.s6_addr32[0] = htonl(0xfe800000);
3963                         addr.s6_addr32[1] = 0;
3964 
3965                         if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
3966                             ipv6_addr_equal(&ifp->addr, &addr)) {
3967                                 /* DAD failed for link-local based on MAC */
3968                                 idev->cnf.disable_ipv6 = 1;
3969 
3970                                 pr_info("%s: IPv6 being disabled!\n",
3971                                         ifp->idev->dev->name);
3972                                 disable_ipv6 = true;
3973                         }
3974                 }
3975         }
3976         spin_unlock_bh(&ifp->lock);
3977 
3978         if (action == DAD_BEGIN) {
3979                 addrconf_dad_begin(ifp);
3980                 goto out;
3981         } else if (action == DAD_ABORT) {
3982                 in6_ifa_hold(ifp);
3983                 addrconf_dad_stop(ifp, 1);
3984                 if (disable_ipv6)
3985                         addrconf_ifdown(idev->dev, 0);
3986                 goto out;
3987         }
3988 
3989         if (!ifp->dad_probes && addrconf_dad_end(ifp))
3990                 goto out;
3991 
3992         write_lock_bh(&idev->lock);
3993         if (idev->dead || !(idev->if_flags & IF_READY)) {
3994                 write_unlock_bh(&idev->lock);
3995                 goto out;
3996         }
3997 
3998         spin_lock(&ifp->lock);
3999         if (ifp->state == INET6_IFADDR_STATE_DEAD) {
4000                 spin_unlock(&ifp->lock);
4001                 write_unlock_bh(&idev->lock);
4002                 goto out;
4003         }
4004 
4005         if (ifp->dad_probes == 0) {
4006                 bool send_na = false;
4007 
4008                 /*
4009                  * DAD was successful
4010                  */
4011 
4012                 if (ifp->flags & IFA_F_TENTATIVE &&
4013                     !(ifp->flags & IFA_F_OPTIMISTIC))
4014                         send_na = true;
4015                 bump_id = ifp->flags & IFA_F_TENTATIVE;
4016                 ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
4017                 spin_unlock(&ifp->lock);
4018                 write_unlock_bh(&idev->lock);
4019 
4020                 addrconf_dad_completed(ifp, bump_id, send_na);
4021 
4022                 goto out;
4023         }
4024 
4025         ifp->dad_probes--;
4026         addrconf_mod_dad_work(ifp,
4027                               NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME));
4028         spin_unlock(&ifp->lock);
4029         write_unlock_bh(&idev->lock);
4030 
4031         /* send a neighbour solicitation for our addr */
4032         addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
4033         ndisc_send_ns(ifp->idev->dev, &ifp->addr, &mcaddr, &in6addr_any,
4034                       ifp->dad_nonce);
4035 out:
4036         in6_ifa_put(ifp);
4037         rtnl_unlock();
4038 }
4039 
4040 /* ifp->idev must be at least read locked */
4041 static bool ipv6_lonely_lladdr(struct inet6_ifaddr *ifp)
4042 {
4043         struct inet6_ifaddr *ifpiter;
4044         struct inet6_dev *idev = ifp->idev;
4045 
4046         list_for_each_entry_reverse(ifpiter, &idev->addr_list, if_list) {
4047                 if (ifpiter->scope > IFA_LINK)
4048                         break;
4049                 if (ifp != ifpiter && ifpiter->scope == IFA_LINK &&
4050                     (ifpiter->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE|
4051                                        IFA_F_OPTIMISTIC|IFA_F_DADFAILED)) ==
4052                     IFA_F_PERMANENT)
4053                         return false;
4054         }
4055         return true;
4056 }
4057 
4058 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
4059                                    bool send_na)
4060 {
4061         struct net_device *dev = ifp->idev->dev;
4062         struct in6_addr lladdr;
4063         bool send_rs, send_mld;
4064 
4065         addrconf_del_dad_work(ifp);
4066 
4067         /*
4068          *      Configure the address for reception. Now it is valid.
4069          */
4070 
4071         ipv6_ifa_notify(RTM_NEWADDR, ifp);
4072 
4073         /* If added prefix is link local and we are prepared to process
4074            router advertisements, start sending router solicitations.
4075          */
4076 
4077         read_lock_bh(&ifp->idev->lock);
4078         send_mld = ifp->scope == IFA_LINK && ipv6_lonely_lladdr(ifp);
4079         send_rs = send_mld &&
4080                   ipv6_accept_ra(ifp->idev) &&
4081                   ifp->idev->cnf.rtr_solicits != 0 &&
4082                   (dev->flags&IFF_LOOPBACK) == 0;
4083         read_unlock_bh(&ifp->idev->lock);
4084 
4085         /* While dad is in progress mld report's source address is in6_addrany.
4086          * Resend with proper ll now.
4087          */
4088         if (send_mld)
4089                 ipv6_mc_dad_complete(ifp->idev);
4090 
4091         /* send unsolicited NA if enabled */
4092         if (send_na &&
4093             (ifp->idev->cnf.ndisc_notify ||
4094              dev_net(dev)->ipv6.devconf_all->ndisc_notify)) {
4095                 ndisc_send_na(dev, &in6addr_linklocal_allnodes, &ifp->addr,
4096                               /*router=*/ !!ifp->idev->cnf.forwarding,
4097                               /*solicited=*/ false, /*override=*/ true,
4098                               /*inc_opt=*/ true);
4099         }
4100 
4101         if (send_rs) {
4102                 /*
4103                  *      If a host as already performed a random delay
4104                  *      [...] as part of DAD [...] there is no need
4105                  *      to delay again before sending the first RS
4106                  */
4107                 if (ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4108                         return;
4109                 ndisc_send_rs(dev, &lladdr, &in6addr_linklocal_allrouters);
4110 
4111                 write_lock_bh(&ifp->idev->lock);
4112                 spin_lock(&ifp->lock);
4113                 ifp->idev->rs_interval = rfc3315_s14_backoff_init(
4114                         ifp->idev->cnf.rtr_solicit_interval);
4115                 ifp->idev->rs_probes = 1;
4116                 ifp->idev->if_flags |= IF_RS_SENT;
4117                 addrconf_mod_rs_timer(ifp->idev, ifp->idev->rs_interval);
4118                 spin_unlock(&ifp->lock);
4119                 write_unlock_bh(&ifp->idev->lock);
4120         }
4121 
4122         if (bump_id)
4123                 rt_genid_bump_ipv6(dev_net(dev));
4124 
4125         /* Make sure that a new temporary address will be created
4126          * before this temporary address becomes deprecated.
4127          */
4128         if (ifp->flags & IFA_F_TEMPORARY)
4129                 addrconf_verify_rtnl();
4130 }
4131 
4132 static void addrconf_dad_run(struct inet6_dev *idev)
4133 {
4134         struct inet6_ifaddr *ifp;
4135 
4136         read_lock_bh(&idev->lock);
4137         list_for_each_entry(ifp, &idev->addr_list, if_list) {
4138                 spin_lock(&ifp->lock);
4139                 if (ifp->flags & IFA_F_TENTATIVE &&
4140                     ifp->state == INET6_IFADDR_STATE_DAD)
4141                         addrconf_dad_kick(ifp);
4142                 spin_unlock(&ifp->lock);
4143         }
4144         read_unlock_bh(&idev->lock);
4145 }
4146 
4147 #ifdef CONFIG_PROC_FS
4148 struct if6_iter_state {
4149         struct seq_net_private p;
4150         int bucket;
4151         int offset;
4152 };
4153 
4154 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
4155 {
4156         struct if6_iter_state *state = seq->private;
4157         struct net *net = seq_file_net(seq);
4158         struct inet6_ifaddr *ifa = NULL;
4159         int p = 0;
4160 
4161         /* initial bucket if pos is 0 */
4162         if (pos == 0) {
4163                 state->bucket = 0;
4164                 state->offset = 0;
4165         }
4166 
4167         for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
4168                 hlist_for_each_entry_rcu(ifa, &inet6_addr_lst[state->bucket],
4169                                          addr_lst) {
4170                         if (!net_eq(dev_net(ifa->idev->dev), net))
4171                                 continue;
4172                         /* sync with offset */
4173                         if (p < state->offset) {
4174                                 p++;
4175                                 continue;
4176                         }
4177                         state->offset++;
4178                         return ifa;
4179                 }
4180 
4181                 /* prepare for next bucket */
4182                 state->offset = 0;
4183                 p = 0;
4184         }
4185         return NULL;
4186 }
4187 
4188 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
4189                                          struct inet6_ifaddr *ifa)
4190 {
4191         struct if6_iter_state *state = seq->private;
4192         struct net *net = seq_file_net(seq);
4193 
4194         hlist_for_each_entry_continue_rcu(ifa, addr_lst) {
4195                 if (!net_eq(dev_net(ifa->idev->dev), net))
4196                         continue;
4197                 state->offset++;
4198                 return ifa;
4199         }
4200 
4201         while (++state->bucket < IN6_ADDR_HSIZE) {
4202                 state->offset = 0;
4203                 hlist_for_each_entry_rcu(ifa,
4204                                      &inet6_addr_lst[state->bucket], addr_lst) {
4205                         if (!net_eq(dev_net(ifa->idev->dev), net))
4206                                 continue;
4207                         state->offset++;
4208                         return ifa;
4209                 }
4210         }
4211 
4212         return NULL;
4213 }
4214 
4215 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
4216         __acquires(rcu)
4217 {
4218         rcu_read_lock();
4219         return if6_get_first(seq, *pos);
4220 }
4221 
4222 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4223 {
4224         struct inet6_ifaddr *ifa;
4225 
4226         ifa = if6_get_next(seq, v);
4227         ++*pos;
4228         return ifa;
4229 }
4230 
4231 static void if6_seq_stop(struct seq_file *seq, void *v)
4232         __releases(rcu)
4233 {
4234         rcu_read_unlock();
4235 }
4236 
4237 static int if6_seq_show(struct seq_file *seq, void *v)
4238 {
4239         struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
4240         seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
4241                    &ifp->addr,
4242                    ifp->idev->dev->ifindex,
4243                    ifp->prefix_len,
4244                    ifp->scope,
4245                    (u8) ifp->flags,
4246                    ifp->idev->dev->name);
4247         return 0;
4248 }
4249 
4250 static const struct seq_operations if6_seq_ops = {
4251         .start  = if6_seq_start,
4252         .next   = if6_seq_next,
4253         .show   = if6_seq_show,
4254         .stop   = if6_seq_stop,
4255 };
4256 
4257 static int if6_seq_open(struct inode *inode, struct file *file)
4258 {
4259         return seq_open_net(inode, file, &if6_seq_ops,
4260                             sizeof(struct if6_iter_state));
4261 }
4262 
4263 static const struct file_operations if6_fops = {
4264         .open           = if6_seq_open,
4265         .read           = seq_read,
4266         .llseek         = seq_lseek,
4267         .release        = seq_release_net,
4268 };
4269 
4270 static int __net_init if6_proc_net_init(struct net *net)
4271 {
4272         if (!proc_create("if_inet6", 0444, net->proc_net, &if6_fops))
4273                 return -ENOMEM;
4274         return 0;
4275 }
4276 
4277 static void __net_exit if6_proc_net_exit(struct net *net)
4278 {
4279         remove_proc_entry("if_inet6", net->proc_net);
4280 }
4281 
4282 static struct pernet_operations if6_proc_net_ops = {
4283         .init = if6_proc_net_init,
4284         .exit = if6_proc_net_exit,
4285 };
4286 
4287 int __init if6_proc_init(void)
4288 {
4289         return register_pernet_subsys(&if6_proc_net_ops);
4290 }
4291 
4292 void if6_proc_exit(void)
4293 {
4294         unregister_pernet_subsys(&if6_proc_net_ops);
4295 }
4296 #endif  /* CONFIG_PROC_FS */
4297 
4298 #if IS_ENABLED(CONFIG_IPV6_MIP6)
4299 /* Check if address is a home address configured on any interface. */
4300 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
4301 {
4302         unsigned int hash = inet6_addr_hash(net, addr);
4303         struct inet6_ifaddr *ifp = NULL;
4304         int ret = 0;
4305 
4306         rcu_read_lock();
4307         hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
4308                 if (!net_eq(dev_net(ifp->idev->dev), net))
4309                         continue;
4310                 if (ipv6_addr_equal(&ifp->addr, addr) &&
4311                     (ifp->flags & IFA_F_HOMEADDRESS)) {
4312                         ret = 1;
4313                         break;
4314                 }
4315         }
4316         rcu_read_unlock();
4317         return ret;
4318 }
4319 #endif
4320 
4321 /*
4322  *      Periodic address status verification
4323  */
4324 
4325 static void addrconf_verify_rtnl(void)
4326 {
4327         unsigned long now, next, next_sec, next_sched;
4328         struct inet6_ifaddr *ifp;
4329         int i;
4330 
4331         ASSERT_RTNL();
4332 
4333         rcu_read_lock_bh();
4334         now = jiffies;
4335         next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
4336 
4337         cancel_delayed_work(&addr_chk_work);
4338 
4339         for (i = 0; i < IN6_ADDR_HSIZE; i++) {
4340 restart:
4341                 hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[i], addr_lst) {
4342                         unsigned long age;
4343 
4344                         /* When setting preferred_lft to a value not zero or
4345                          * infinity, while valid_lft is infinity
4346                          * IFA_F_PERMANENT has a non-infinity life time.
4347                          */
4348                         if ((ifp->flags & IFA_F_PERMANENT) &&
4349                             (ifp->prefered_lft == INFINITY_LIFE_TIME))
4350                                 continue;
4351 
4352                         spin_lock(&ifp->lock);
4353                         /* We try to batch several events at once. */
4354                         age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
4355 
4356                         if (ifp->valid_lft != INFINITY_LIFE_TIME &&
4357                             age >= ifp->valid_lft) {
4358                                 spin_unlock(&ifp->lock);
4359                                 in6_ifa_hold(ifp);
4360                                 ipv6_del_addr(ifp);
4361                                 goto restart;
4362                         } else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
4363                                 spin_unlock(&ifp->lock);
4364                                 continue;
4365                         } else if (age >= ifp->prefered_lft) {
4366                                 /* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
4367                                 int deprecate = 0;
4368 
4369                                 if (!(ifp->flags&IFA_F_DEPRECATED)) {
4370                                         deprecate = 1;
4371                                         ifp->flags |= IFA_F_DEPRECATED;
4372                                 }
4373 
4374                                 if ((ifp->valid_lft != INFINITY_LIFE_TIME) &&
4375                                     (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)))
4376                                         next = ifp->tstamp + ifp->valid_lft * HZ;
4377 
4378                                 spin_unlock(&ifp->lock);
4379 
4380                                 if (deprecate) {
4381                                         in6_ifa_hold(ifp);
4382 
4383                                         ipv6_ifa_notify(0, ifp);
4384                                         in6_ifa_put(ifp);
4385                                         goto restart;
4386                                 }
4387                         } else if ((ifp->flags&IFA_F_TEMPORARY) &&
4388                                    !(ifp->flags&IFA_F_TENTATIVE)) {
4389                                 unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
4390                                         ifp->idev->cnf.dad_transmits *
4391                                         NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME) / HZ;
4392 
4393                                 if (age >= ifp->prefered_lft - regen_advance) {
4394                                         struct inet6_ifaddr *ifpub = ifp->ifpub;
4395                                         if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4396                                                 next = ifp->tstamp + ifp->prefered_lft * HZ;
4397                                         if (!ifp->regen_count && ifpub) {
4398                                                 ifp->regen_count++;
4399                                                 in6_ifa_hold(ifp);
4400                                                 in6_ifa_hold(ifpub);
4401                                                 spin_unlock(&ifp->lock);
4402 
4403                                                 spin_lock(&ifpub->lock);
4404                                                 ifpub->regen_count = 0;
4405                                                 spin_unlock(&ifpub->lock);
4406                                                 rcu_read_unlock_bh();
4407                                                 ipv6_create_tempaddr(ifpub, ifp, true);
4408                                                 in6_ifa_put(ifpub);
4409                                                 in6_ifa_put(ifp);
4410                                                 rcu_read_lock_bh();
4411                                                 goto restart;
4412                                         }
4413                                 } else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
4414                                         next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
4415                                 spin_unlock(&ifp->lock);
4416                         } else {
4417                                 /* ifp->prefered_lft <= ifp->valid_lft */
4418                                 if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4419                                         next = ifp->tstamp + ifp->prefered_lft * HZ;
4420                                 spin_unlock(&ifp->lock);
4421                         }
4422                 }
4423         }
4424 
4425         next_sec = round_jiffies_up(next);
4426         next_sched = next;
4427 
4428         /* If rounded timeout is accurate enough, accept it. */
4429         if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
4430                 next_sched = next_sec;
4431 
4432         /* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
4433         if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
4434                 next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
4435 
4436         pr_debug("now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
4437                  now, next, next_sec, next_sched);
4438         mod_delayed_work(addrconf_wq, &addr_chk_work, next_sched - now);
4439         rcu_read_unlock_bh();
4440 }
4441 
4442 static void addrconf_verify_work(struct work_struct *w)
4443 {
4444         rtnl_lock();
4445         addrconf_verify_rtnl();
4446         rtnl_unlock();
4447 }
4448 
4449 static void addrconf_verify(void)
4450 {
4451         mod_delayed_work(addrconf_wq, &addr_chk_work, 0);
4452 }
4453 
4454 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
4455                                      struct in6_addr **peer_pfx)
4456 {
4457         struct in6_addr *pfx = NULL;
4458 
4459         *peer_pfx = NULL;
4460 
4461         if (addr)
4462                 pfx = nla_data(addr);
4463 
4464         if (local) {
4465                 if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
4466                         *peer_pfx = pfx;
4467                 pfx = nla_data(local);
4468         }
4469 
4470         return pfx;
4471 }
4472 
4473 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
4474         [IFA_ADDRESS]           = { .len = sizeof(struct in6_addr) },
4475         [IFA_LOCAL]             = { .len = sizeof(struct in6_addr) },
4476         [IFA_CACHEINFO]         = { .len = sizeof(struct ifa_cacheinfo) },
4477         [IFA_FLAGS]             = { .len = sizeof(u32) },
4478 };
4479 
4480 static int
4481 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh,
4482                   struct netlink_ext_ack *extack)
4483 {
4484         struct net *net = sock_net(skb->sk);
4485         struct ifaddrmsg *ifm;
4486         struct nlattr *tb[IFA_MAX+1];
4487         struct in6_addr *pfx, *peer_pfx;
4488         u32 ifa_flags;
4489         int err;
4490 
4491         err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy,
4492                           extack);
4493         if (err < 0)
4494                 return err;
4495 
4496         ifm = nlmsg_data(nlh);
4497         pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4498         if (!pfx)
4499                 return -EINVAL;
4500 
4501         ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
4502 
4503         /* We ignore other flags so far. */
4504         ifa_flags &= IFA_F_MANAGETEMPADDR;
4505 
4506         return inet6_addr_del(net, ifm->ifa_index, ifa_flags, pfx,
4507                               ifm->ifa_prefixlen);
4508 }
4509 
4510 static int inet6_addr_modify(struct inet6_ifaddr *ifp, u32 ifa_flags,
4511                              u32 prefered_lft, u32 valid_lft)
4512 {
4513         u32 flags;
4514         clock_t expires;
4515         unsigned long timeout;
4516         bool was_managetempaddr;
4517         bool had_prefixroute;
4518 
4519         ASSERT_RTNL();
4520 
4521         if (!valid_lft || (prefered_lft > valid_lft))
4522                 return -EINVAL;
4523 
4524         if (ifa_flags & IFA_F_MANAGETEMPADDR &&
4525             (ifp->flags & IFA_F_TEMPORARY || ifp->prefix_len != 64))
4526                 return -EINVAL;
4527 
4528         if (!(ifp->flags & IFA_F_TENTATIVE) || ifp->flags & IFA_F_DADFAILED)
4529                 ifa_flags &= ~IFA_F_OPTIMISTIC;
4530 
4531         timeout = addrconf_timeout_fixup(valid_lft, HZ);
4532         if (addrconf_finite_timeout(timeout)) {
4533                 expires = jiffies_to_clock_t(timeout * HZ);
4534                 valid_lft = timeout;
4535                 flags = RTF_EXPIRES;
4536         } else {
4537                 expires = 0;
4538                 flags = 0;
4539                 ifa_flags |= IFA_F_PERMANENT;
4540         }
4541 
4542         timeout = addrconf_timeout_fixup(prefered_lft, HZ);
4543         if (addrconf_finite_timeout(timeout)) {
4544                 if (timeout == 0)
4545                         ifa_flags |= IFA_F_DEPRECATED;
4546                 prefered_lft = timeout;
4547         }
4548 
4549         spin_lock_bh(&ifp->lock);
4550         was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;
4551         had_prefixroute = ifp->flags & IFA_F_PERMANENT &&
4552                           !(ifp->flags & IFA_F_NOPREFIXROUTE);
4553         ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |
4554                         IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4555                         IFA_F_NOPREFIXROUTE);
4556         ifp->flags |= ifa_flags;
4557         ifp->tstamp = jiffies;
4558         ifp->valid_lft = valid_lft;
4559         ifp->prefered_lft = prefered_lft;
4560 
4561         spin_unlock_bh(&ifp->lock);
4562         if (!(ifp->flags&IFA_F_TENTATIVE))
4563                 ipv6_ifa_notify(0, ifp);
4564 
4565         if (!(ifa_flags & IFA_F_NOPREFIXROUTE)) {
4566                 addrconf_prefix_route(&ifp->addr, ifp->prefix_len, ifp->idev->dev,
4567                                       expires, flags);
4568         } else if (had_prefixroute) {
4569                 enum cleanup_prefix_rt_t action;
4570                 unsigned long rt_expires;
4571 
4572                 write_lock_bh(&ifp->idev->lock);
4573                 action = check_cleanup_prefix_route(ifp, &rt_expires);
4574                 write_unlock_bh(&ifp->idev->lock);
4575 
4576                 if (action != CLEANUP_PREFIX_RT_NOP) {
4577                         cleanup_prefix_route(ifp, rt_expires,
4578                                 action == CLEANUP_PREFIX_RT_DEL);
4579                 }
4580         }
4581 
4582         if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {
4583                 if (was_managetempaddr && !(ifp->flags & IFA_F_MANAGETEMPADDR))
4584                         valid_lft = prefered_lft = 0;
4585                 manage_tempaddrs(ifp->idev, ifp, valid_lft, prefered_lft,
4586                                  !was_managetempaddr, jiffies);
4587         }
4588 
4589         addrconf_verify_rtnl();
4590 
4591         return 0;
4592 }
4593 
4594 static int
4595 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
4596                   struct netlink_ext_ack *extack)
4597 {
4598         struct net *net = sock_net(skb->sk);
4599         struct ifaddrmsg *ifm;
4600         struct nlattr *tb[IFA_MAX+1];
4601         struct in6_addr *pfx, *peer_pfx;
4602         struct inet6_ifaddr *ifa;
4603         struct net_device *dev;
4604         struct inet6_dev *idev;
4605         u32 valid_lft = INFINITY_LIFE_TIME, preferred_lft = INFINITY_LIFE_TIME;
4606         u32 ifa_flags;
4607         int err;
4608 
4609         err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy,
4610                           extack);
4611         if (err < 0)
4612                 return err;
4613 
4614         ifm = nlmsg_data(nlh);
4615         pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4616         if (!pfx)
4617                 return -EINVAL;
4618 
4619         if (tb[IFA_CACHEINFO]) {
4620                 struct ifa_cacheinfo *ci;
4621 
4622                 ci = nla_data(tb[IFA_CACHEINFO]);
4623                 valid_lft = ci->ifa_valid;
4624                 preferred_lft = ci->ifa_prefered;
4625         } else {
4626                 preferred_lft = INFINITY_LIFE_TIME;
4627                 valid_lft = INFINITY_LIFE_TIME;
4628         }
4629 
4630         dev =  __dev_get_by_index(net, ifm->ifa_index);
4631         if (!dev)
4632                 return -ENODEV;
4633 
4634         ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
4635 
4636         /* We ignore other flags so far. */
4637         ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4638                      IFA_F_NOPREFIXROUTE | IFA_F_MCAUTOJOIN | IFA_F_OPTIMISTIC;
4639 
4640         idev = ipv6_find_idev(dev);
4641         if (IS_ERR(idev))
4642                 return PTR_ERR(idev);
4643 
4644         if (!ipv6_allow_optimistic_dad(net, idev))
4645                 ifa_flags &= ~IFA_F_OPTIMISTIC;
4646 
4647         if (ifa_flags & IFA_F_NODAD && ifa_flags & IFA_F_OPTIMISTIC) {
4648                 NL_SET_ERR_MSG(extack, "IFA_F_NODAD and IFA_F_OPTIMISTIC are mutually exclusive");
4649                 return -EINVAL;
4650         }
4651 
4652         ifa = ipv6_get_ifaddr(net, pfx, dev, 1);
4653         if (!ifa) {
4654                 /*
4655                  * It would be best to check for !NLM_F_CREATE here but
4656                  * userspace already relies on not having to provide this.
4657                  */
4658                 return inet6_addr_add(net, ifm->ifa_index, pfx, peer_pfx,
4659                                       ifm->ifa_prefixlen, ifa_flags,
4660                                       preferred_lft, valid_lft, extack);
4661         }
4662 
4663         if (nlh->nlmsg_flags & NLM_F_EXCL ||
4664             !(nlh->nlmsg_flags & NLM_F_REPLACE))
4665                 err = -EEXIST;
4666         else
4667                 err = inet6_addr_modify(ifa, ifa_flags, preferred_lft, valid_lft);
4668 
4669         in6_ifa_put(ifa);
4670 
4671         return err;
4672 }
4673 
4674 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u32 flags,
4675                           u8 scope, int ifindex)
4676 {
4677         struct ifaddrmsg *ifm;
4678 
4679         ifm = nlmsg_data(nlh);
4680         ifm->ifa_family = AF_INET6;
4681         ifm->ifa_prefixlen = prefixlen;
4682         ifm->ifa_flags = flags;
4683         ifm->ifa_scope = scope;
4684         ifm->ifa_index = ifindex;
4685 }
4686 
4687 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
4688                          unsigned long tstamp, u32 preferred, u32 valid)
4689 {
4690         struct ifa_cacheinfo ci;
4691 
4692         ci.cstamp = cstamp_delta(cstamp);
4693         ci.tstamp = cstamp_delta(tstamp);
4694         ci.ifa_prefered = preferred;
4695         ci.ifa_valid = valid;
4696 
4697         return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
4698 }
4699 
4700 static inline int rt_scope(int ifa_scope)
4701 {
4702         if (ifa_scope & IFA_HOST)
4703                 return RT_SCOPE_HOST;
4704         else if (ifa_scope & IFA_LINK)
4705                 return RT_SCOPE_LINK;
4706         else if (ifa_scope & IFA_SITE)
4707                 return RT_SCOPE_SITE;
4708         else
4709                 return RT_SCOPE_UNIVERSE;
4710 }
4711 
4712 static inline int inet6_ifaddr_msgsize(void)
4713 {
4714         return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
4715                + nla_total_size(16) /* IFA_LOCAL */
4716                + nla_total_size(16) /* IFA_ADDRESS */
4717                + nla_total_size(sizeof(struct ifa_cacheinfo))
4718                + nla_total_size(4)  /* IFA_FLAGS */;
4719 }
4720 
4721 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
4722                              u32 portid, u32 seq, int event, unsigned int flags)
4723 {
4724         struct nlmsghdr  *nlh;
4725         u32 preferred, valid;
4726 
4727         nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4728         if (!nlh)
4729                 return -EMSGSIZE;
4730 
4731         put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
4732                       ifa->idev->dev->ifindex);
4733 
4734         if (!((ifa->flags&IFA_F_PERMANENT) &&
4735               (ifa->prefered_lft == INFINITY_LIFE_TIME))) {
4736                 preferred = ifa->prefered_lft;
4737                 valid = ifa->valid_lft;
4738                 if (preferred != INFINITY_LIFE_TIME) {
4739                         long tval = (jiffies - ifa->tstamp)/HZ;
4740                         if (preferred > tval)
4741                                 preferred -= tval;
4742                         else
4743                                 preferred = 0;
4744                         if (valid != INFINITY_LIFE_TIME) {
4745                                 if (valid > tval)
4746                                         valid -= tval;
4747                                 else
4748                                         valid = 0;
4749                         }
4750                 }
4751         } else {
4752                 preferred = INFINITY_LIFE_TIME;
4753                 valid = INFINITY_LIFE_TIME;
4754         }
4755 
4756         if (!ipv6_addr_any(&ifa->peer_addr)) {
4757                 if (nla_put_in6_addr(skb, IFA_LOCAL, &ifa->addr) < 0 ||
4758                     nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->peer_addr) < 0)
4759                         goto error;
4760         } else
4761                 if (nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->addr) < 0)
4762                         goto error;
4763 
4764         if (put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0)
4765                 goto error;
4766 
4767         if (nla_put_u32(skb, IFA_FLAGS, ifa->flags) < 0)
4768                 goto error;
4769 
4770         nlmsg_end(skb, nlh);
4771         return 0;
4772 
4773 error:
4774         nlmsg_cancel(skb, nlh);
4775         return -EMSGSIZE;
4776 }
4777 
4778 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
4779                                 u32 portid, u32 seq, int event, u16 flags)
4780 {
4781         struct nlmsghdr  *nlh;
4782         u8 scope = RT_SCOPE_UNIVERSE;
4783         int ifindex = ifmca->idev->dev->ifindex;
4784 
4785         if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
4786                 scope = RT_SCOPE_SITE;
4787 
4788         nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4789         if (!nlh)
4790                 return -EMSGSIZE;
4791 
4792         put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4793         if (nla_put_in6_addr(skb, IFA_MULTICAST, &ifmca->mca_addr) < 0 ||
4794             put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
4795                           INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4796                 nlmsg_cancel(skb, nlh);
4797                 return -EMSGSIZE;
4798         }
4799 
4800         nlmsg_end(skb, nlh);
4801         return 0;
4802 }
4803 
4804 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
4805                                 u32 portid, u32 seq, int event, unsigned int flags)
4806 {
4807         struct nlmsghdr  *nlh;
4808         u8 scope = RT_SCOPE_UNIVERSE;
4809         int ifindex = ifaca->aca_idev->dev->ifindex;
4810 
4811         if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
4812                 scope = RT_SCOPE_SITE;
4813 
4814         nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4815         if (!nlh)
4816                 return -EMSGSIZE;
4817 
4818         put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4819         if (nla_put_in6_addr(skb, IFA_ANYCAST, &ifaca->aca_addr) < 0 ||
4820             put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
4821                           INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4822                 nlmsg_cancel(skb, nlh);
4823                 return -EMSGSIZE;
4824         }
4825 
4826         nlmsg_end(skb, nlh);
4827         return 0;
4828 }
4829 
4830 enum addr_type_t {
4831         UNICAST_ADDR,
4832         MULTICAST_ADDR,
4833         ANYCAST_ADDR,
4834 };
4835 
4836 /* called with rcu_read_lock() */
4837 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
4838                           struct netlink_callback *cb, enum addr_type_t type,
4839                           int s_ip_idx, int *p_ip_idx)
4840 {
4841         struct ifmcaddr6 *ifmca;
4842         struct ifacaddr6 *ifaca;
4843         int err = 1;
4844         int ip_idx = *p_ip_idx;
4845 
4846         read_lock_bh(&idev->lock);
4847         switch (type) {
4848         case UNICAST_ADDR: {
4849                 struct inet6_ifaddr *ifa;
4850 
4851                 /* unicast address incl. temp addr */
4852                 list_for_each_entry(ifa, &idev->addr_list, if_list) {
4853                         if (++ip_idx < s_ip_idx)
4854                                 continue;
4855                         err = inet6_fill_ifaddr(skb, ifa,
4856                                                 NETLINK_CB(cb->skb).portid,
4857                                                 cb->nlh->nlmsg_seq,
4858                                                 RTM_NEWADDR,
4859                                                 NLM_F_MULTI);
4860                         if (err < 0)
4861                                 break;
4862                         nl_dump_check_consistent(cb, nlmsg_hdr(skb));
4863                 }
4864                 break;
4865         }
4866         case MULTICAST_ADDR:
4867                 /* multicast address */
4868                 for (ifmca = idev->mc_list; ifmca;
4869                      ifmca = ifmca->next, ip_idx++) {
4870                         if (ip_idx < s_ip_idx)
4871                                 continue;
4872                         err = inet6_fill_ifmcaddr(skb, ifmca,
4873                                                   NETLINK_CB(cb->skb).portid,
4874                                                   cb->nlh->nlmsg_seq,
4875                                                   RTM_GETMULTICAST,
4876                                                   NLM_F_MULTI);
4877                         if (err < 0)
4878                                 break;
4879                 }
4880                 break;
4881         case ANYCAST_ADDR:
4882                 /* anycast address */
4883                 for (ifaca = idev->ac_list; ifaca;
4884                      ifaca = ifaca->aca_next, ip_idx++) {
4885                         if (ip_idx < s_ip_idx)
4886                                 continue;
4887                         err = inet6_fill_ifacaddr(skb, ifaca,
4888                                                   NETLINK_CB(cb->skb).portid,
4889                                                   cb->nlh->nlmsg_seq,
4890                                                   RTM_GETANYCAST,
4891                                                   NLM_F_MULTI);
4892                         if (err < 0)
4893                                 break;
4894                 }
4895                 break;
4896         default:
4897                 break;
4898         }
4899         read_unlock_bh(&idev->lock);
4900         *p_ip_idx = ip_idx;
4901         return err;
4902 }
4903 
4904 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
4905                            enum addr_type_t type)
4906 {
4907         struct net *net = sock_net(skb->sk);
4908         int h, s_h;
4909         int idx, ip_idx;
4910         int s_idx, s_ip_idx;
4911         struct net_device *dev;
4912         struct inet6_dev *idev;
4913         struct hlist_head *head;
4914 
4915         s_h = cb->args[0];
4916         s_idx = idx = cb->args[1];
4917         s_ip_idx = ip_idx = cb->args[2];
4918 
4919         rcu_read_lock();
4920         cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^ net->dev_base_seq;
4921         for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
4922                 idx = 0;
4923                 head = &net->dev_index_head[h];
4924                 hlist_for_each_entry_rcu(dev, head, index_hlist) {
4925                         if (idx < s_idx)
4926                                 goto cont;
4927                         if (h > s_h || idx > s_idx)
4928                                 s_ip_idx = 0;
4929                         ip_idx = 0;
4930                         idev = __in6_dev_get(dev);
4931                         if (!idev)
4932                                 goto cont;
4933 
4934                         if (in6_dump_addrs(idev, skb, cb, type,
4935                                            s_ip_idx, &ip_idx) < 0)
4936                                 goto done;
4937 cont:
4938                         idx++;
4939                 }
4940         }
4941 done:
4942         rcu_read_unlock();
4943         cb->args[0] = h;
4944         cb->args[1] = idx;
4945         cb->args[2] = ip_idx;
4946 
4947         return skb->len;
4948 }
4949 
4950 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
4951 {
4952         enum addr_type_t type = UNICAST_ADDR;
4953 
4954         return inet6_dump_addr(skb, cb, type);
4955 }
4956 
4957 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
4958 {
4959         enum addr_type_t type = MULTICAST_ADDR;
4960 
4961         return inet6_dump_addr(skb, cb, type);
4962 }
4963 
4964 
4965 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
4966 {
4967         enum addr_type_t type = ANYCAST_ADDR;
4968 
4969         return inet6_dump_addr(skb, cb, type);
4970 }
4971 
4972 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
4973                              struct netlink_ext_ack *extack)
4974 {
4975         struct net *net = sock_net(in_skb->sk);
4976         struct ifaddrmsg *ifm;
4977         struct nlattr *tb[IFA_MAX+1];
4978         struct in6_addr *addr = NULL, *peer;
4979         struct net_device *dev = NULL;
4980         struct inet6_ifaddr *ifa;
4981         struct sk_buff *skb;
4982         int err;
4983 
4984         err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy,
4985                           extack);
4986         if (err < 0)
4987                 return err;
4988 
4989         addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
4990         if (!addr)
4991                 return -EINVAL;
4992 
4993         ifm = nlmsg_data(nlh);
4994         if (ifm->ifa_index)
4995                 dev = dev_get_by_index(net, ifm->ifa_index);
4996 
4997         ifa = ipv6_get_ifaddr(net, addr, dev, 1);
4998         if (!ifa) {
4999                 err = -EADDRNOTAVAIL;
5000                 goto errout;
5001         }
5002 
5003         skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
5004         if (!skb) {
5005                 err = -ENOBUFS;
5006                 goto errout_ifa;
5007         }
5008 
5009         err = inet6_fill_ifaddr(skb, ifa, NETLINK_CB(in_skb).portid,
5010                                 nlh->nlmsg_seq, RTM_NEWADDR, 0);
5011         if (err < 0) {
5012                 /* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5013                 WARN_ON(err == -EMSGSIZE);
5014                 kfree_skb(skb);
5015                 goto errout_ifa;
5016         }
5017         err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
5018 errout_ifa:
5019         in6_ifa_put(ifa);
5020 errout:
5021         if (dev)
5022                 dev_put(dev);
5023         return err;
5024 }
5025 
5026 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
5027 {
5028         struct sk_buff *skb;
5029         struct net *net = dev_net(ifa->idev->dev);
5030         int err = -ENOBUFS;
5031 
5032         /* Don't send DELADDR notification for TENTATIVE address,
5033          * since NEWADDR notification is sent only after removing
5034          * TENTATIVE flag, if DAD has not failed.
5035          */
5036         if (ifa->flags & IFA_F_TENTATIVE && !(ifa->flags & IFA_F_DADFAILED) &&
5037             event == RTM_DELADDR)
5038                 return;
5039 
5040         skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
5041         if (!skb)
5042                 goto errout;
5043 
5044         err = inet6_fill_ifaddr(skb, ifa, 0, 0, event, 0);
5045         if (err < 0) {
5046                 /* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5047                 WARN_ON(err == -EMSGSIZE);
5048                 kfree_skb(skb);
5049                 goto errout;
5050         }
5051         rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
5052         return;
5053 errout:
5054         if (err < 0)
5055                 rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
5056 }
5057 
5058 static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
5059                                 __s32 *array, int bytes)
5060 {
5061         BUG_ON(bytes < (DEVCONF_MAX * 4));
5062 
5063         memset(array, 0, bytes);
5064         array[DEVCONF_FORWARDING] = cnf->forwarding;
5065         array[DEVCONF_HOPLIMIT] = cnf->hop_limit;
5066         array[DEVCONF_MTU6] = cnf->mtu6;
5067         array[DEVCONF_ACCEPT_RA] = cnf->accept_ra;
5068         array[DEVCONF_ACCEPT_REDIRECTS] = cnf->accept_redirects;
5069         array[DEVCONF_AUTOCONF] = cnf->autoconf;
5070         array[DEVCONF_DAD_TRANSMITS] = cnf->dad_transmits;
5071         array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
5072         array[DEVCONF_RTR_SOLICIT_INTERVAL] =
5073                 jiffies_to_msecs(cnf->rtr_solicit_interval);
5074         array[DEVCONF_RTR_SOLICIT_MAX_INTERVAL] =
5075                 jiffies_to_msecs(cnf->rtr_solicit_max_interval);
5076         array[DEVCONF_RTR_SOLICIT_DELAY] =
5077                 jiffies_to_msecs(cnf->rtr_solicit_delay);
5078         array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;
5079         array[DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL] =
5080                 jiffies_to_msecs(cnf->mldv1_unsolicited_report_interval);
5081         array[DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL] =
5082                 jiffies_to_msecs(cnf->mldv2_unsolicited_report_interval);
5083         array[DEVCONF_USE_TEMPADDR] = cnf->use_tempaddr;
5084         array[DEVCONF_TEMP_VALID_LFT] = cnf->temp_valid_lft;
5085         array[DEVCONF_TEMP_PREFERED_LFT] = cnf->temp_prefered_lft;
5086         array[DEVCONF_REGEN_MAX_RETRY] = cnf->regen_max_retry;
5087         array[DEVCONF_MAX_DESYNC_FACTOR] = cnf->max_desync_factor;
5088         array[DEVCONF_MAX_ADDRESSES] = cnf->max_addresses;
5089         array[DEVCONF_ACCEPT_RA_DEFRTR] = cnf->accept_ra_defrtr;
5090         array[DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT] = cnf->accept_ra_min_hop_limit;
5091         array[DEVCONF_ACCEPT_RA_PINFO] = cnf->accept_ra_pinfo;
5092 #ifdef CONFIG_IPV6_ROUTER_PREF
5093         array[DEVCONF_ACCEPT_RA_RTR_PREF] = cnf->accept_ra_rtr_pref;
5094         array[DEVCONF_RTR_PROBE_INTERVAL] =
5095                 jiffies_to_msecs(cnf->rtr_probe_interval);
5096 #ifdef CONFIG_IPV6_ROUTE_INFO
5097         array[DEVCONF_ACCEPT_RA_RT_INFO_MIN_PLEN] = cnf->accept_ra_rt_info_min_plen;
5098         array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
5099 #endif
5100 #endif
5101         array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
5102         array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
5103 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
5104         array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
5105         array[DEVCONF_USE_OPTIMISTIC] = cnf->use_optimistic;
5106 #endif
5107 #ifdef CONFIG_IPV6_MROUTE
5108         array[DEVCONF_MC_FORWARDING] = cnf->mc_forwarding;
5109 #endif
5110         array[DEVCONF_DISABLE_IPV6] = cnf->disable_ipv6;
5111         array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad;
5112         array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao;
5113         array[DEVCONF_NDISC_NOTIFY] = cnf->ndisc_notify;
5114         array[DEVCONF_SUPPRESS_FRAG_NDISC] = cnf->suppress_frag_ndisc;
5115         array[DEVCONF_ACCEPT_RA_FROM_LOCAL] = cnf->accept_ra_from_local;
5116         array[DEVCONF_ACCEPT_RA_MTU] = cnf->accept_ra_mtu;
5117         array[DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN] = cnf->ignore_routes_with_linkdown;
5118         /* we omit DEVCONF_STABLE_SECRET for now */
5119         array[DEVCONF_USE_OIF_ADDRS_ONLY] = cnf->use_oif_addrs_only;
5120         array[DEVCONF_DROP_UNICAST_IN_L2_MULTICAST] = cnf->drop_unicast_in_l2_multicast;
5121         array[DEVCONF_DROP_UNSOLICITED_NA] = cnf->drop_unsolicited_na;
5122         array[DEVCONF_KEEP_ADDR_ON_DOWN] = cnf->keep_addr_on_down;
5123         array[DEVCONF_SEG6_ENABLED] = cnf->seg6_enabled;
5124 #ifdef CONFIG_IPV6_SEG6_HMAC
5125         array[DEVCONF_SEG6_REQUIRE_HMAC] = cnf->seg6_require_hmac;
5126 #endif
5127         array[DEVCONF_ENHANCED_DAD] = cnf->enhanced_dad;
5128         array[DEVCONF_ADDR_GEN_MODE] = cnf->addr_gen_mode;
5129         array[DEVCONF_DISABLE_POLICY] = cnf->disable_policy;
5130         array[DEVCONF_NDISC_TCLASS] = cnf->ndisc_tclass;
5131 }
5132 
5133 static inline size_t inet6_ifla6_size(void)
5134 {
5135         return nla_total_size(4) /* IFLA_INET6_FLAGS */
5136              + nla_total_size(sizeof(struct ifla_cacheinfo))
5137              + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
5138              + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
5139              + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
5140              + nla_total_size(sizeof(struct in6_addr)); /* IFLA_INET6_TOKEN */
5141 }
5142 
5143 static inline size_t inet6_if_nlmsg_size(void)
5144 {
5145         return NLMSG_ALIGN(sizeof(struct ifinfomsg))
5146                + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
5147                + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
5148                + nla_total_size(4) /* IFLA_MTU */
5149                + nla_total_size(4) /* IFLA_LINK */
5150                + nla_total_size(1) /* IFLA_OPERSTATE */
5151                + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
5152 }
5153 
5154 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
5155                                         int bytes)
5156 {
5157         int i;
5158         int pad = bytes - sizeof(u64) * ICMP6_MIB_MAX;
5159         BUG_ON(pad < 0);
5160 
5161         /* Use put_unaligned() because stats may not be aligned for u64. */
5162         put_unaligned(ICMP6_MIB_MAX, &stats[0]);
5163         for (i = 1; i < ICMP6_MIB_MAX; i++)
5164                 put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
5165 
5166         memset(&stats[ICMP6_MIB_MAX], 0, pad);
5167 }
5168 
5169 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu *mib,
5170                                         int bytes, size_t syncpoff)
5171 {
5172         int i, c;
5173         u64 buff[IPSTATS_MIB_MAX];
5174         int pad = bytes - sizeof(u64) * IPSTATS_MIB_MAX;
5175 
5176         BUG_ON(pad < 0);
5177 
5178         memset(buff, 0, sizeof(buff));
5179         buff[0] = IPSTATS_MIB_MAX;
5180 
5181         for_each_possible_cpu(c) {
5182                 for (i = 1; i < IPSTATS_MIB_MAX; i++)
5183                         buff[i] += snmp_get_cpu_field64(mib, c, i, syncpoff);
5184         }
5185 
5186         memcpy(stats, buff, IPSTATS_MIB_MAX * sizeof(u64));
5187         memset(&stats[IPSTATS_MIB_MAX], 0, pad);
5188 }
5189 
5190 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
5191                              int bytes)
5192 {
5193         switch (attrtype) {
5194         case IFLA_INET6_STATS:
5195                 __snmp6_fill_stats64(stats, idev->stats.ipv6, bytes,
5196                                      offsetof(struct ipstats_mib, syncp));
5197                 break;
5198         case IFLA_INET6_ICMP6STATS:
5199                 __snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, bytes);
5200                 break;
5201         }
5202 }
5203 
5204 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev,
5205                                   u32 ext_filter_mask)
5206 {
5207         struct nlattr *nla;
5208         struct ifla_cacheinfo ci;
5209 
5210         if (nla_put_u32(skb, IFLA_INET6_FLAGS, idev->if_flags))
5211                 goto nla_put_failure;
5212         ci.max_reasm_len = IPV6_MAXPLEN;
5213         ci.tstamp = cstamp_delta(idev->tstamp);
5214         ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
5215         ci.retrans_time = jiffies_to_msecs(NEIGH_VAR(idev->nd_parms, RETRANS_TIME));
5216         if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
5217                 goto nla_put_failure;
5218         nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
5219         if (!nla)
5220                 goto nla_put_failure;
5221         ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
5222 
5223         /* XXX - MC not implemented */
5224 
5225         if (ext_filter_mask & RTEXT_FILTER_SKIP_STATS)
5226                 return 0;
5227 
5228         nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
5229         if (!nla)
5230                 goto nla_put_failure;
5231         snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
5232 
5233         nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
5234         if (!nla)
5235                 goto nla_put_failure;
5236         snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
5237 
5238         nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
5239         if (!nla)
5240                 goto nla_put_failure;
5241 
5242         if (nla_put_u8(skb, IFLA_INET6_ADDR_GEN_MODE, idev->cnf.addr_gen_mode))
5243                 goto nla_put_failure;
5244 
5245         read_lock_bh(&idev->lock);
5246         memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
5247         read_unlock_bh(&idev->lock);
5248 
5249         return 0;
5250 
5251 nla_put_failure:
5252         return -EMSGSIZE;
5253 }
5254 
5255 static size_t inet6_get_link_af_size(const struct net_device *dev,
5256                                      u32 ext_filter_mask)
5257 {
5258         if (!__in6_dev_get(dev))
5259                 return 0;
5260 
5261         return inet6_ifla6_size();
5262 }
5263 
5264 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev,
5265                               u32 ext_filter_mask)
5266 {
5267         struct inet6_dev *idev = __in6_dev_get(dev);
5268 
5269         if (!idev)
5270                 return -ENODATA;
5271 
5272         if (inet6_fill_ifla6_attrs(skb, idev, ext_filter_mask) < 0)
5273                 return -EMSGSIZE;
5274 
5275         return 0;
5276 }
5277 
5278 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token)
5279 {
5280         struct inet6_ifaddr *ifp;
5281         struct net_device *dev = idev->dev;
5282         bool clear_token, update_rs = false;
5283         struct in6_addr ll_addr;
5284 
5285         ASSERT_RTNL();
5286 
5287         if (!token)
5288                 return -EINVAL;
5289         if (dev->flags & (IFF_LOOPBACK | IFF_NOARP))
5290                 return -EINVAL;
5291         if (!ipv6_accept_ra(idev))
5292                 return -EINVAL;
5293         if (idev->cnf.rtr_solicits == 0)
5294                 return -EINVAL;
5295 
5296         write_lock_bh(&idev->lock);
5297 
5298         BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
5299         memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
5300 
5301         write_unlock_bh(&idev->lock);
5302 
5303         clear_token = ipv6_addr_any(token);
5304         if (clear_token)
5305                 goto update_lft;
5306 
5307         if (!idev->dead && (idev->if_flags & IF_READY) &&
5308             !ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
5309                              IFA_F_OPTIMISTIC)) {
5310                 /* If we're not ready, then normal ifup will take care
5311                  * of this. Otherwise, we need to request our rs here.
5312                  */
5313                 ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
5314                 update_rs = true;
5315         }
5316 
5317 update_lft:
5318         write_lock_bh(&idev->lock);
5319 
5320         if (update_rs) {
5321                 idev->if_flags |= IF_RS_SENT;
5322                 idev->rs_interval = rfc3315_s14_backoff_init(
5323                         idev->cnf.rtr_solicit_interval);
5324                 idev->rs_probes = 1;
5325                 addrconf_mod_rs_timer(idev, idev->rs_interval);
5326         }
5327 
5328         /* Well, that's kinda nasty ... */
5329         list_for_each_entry(ifp, &idev->addr_list, if_list) {
5330                 spin_lock(&ifp->lock);
5331                 if (ifp->tokenized) {
5332                         ifp->valid_lft = 0;
5333                         ifp->prefered_lft = 0;
5334                 }
5335                 spin_unlock(&ifp->lock);
5336         }
5337 
5338         write_unlock_bh(&idev->lock);
5339         inet6_ifinfo_notify(RTM_NEWLINK, idev);
5340         addrconf_verify_rtnl();
5341         return 0;
5342 }
5343 
5344 static const struct nla_policy inet6_af_policy[IFLA_INET6_MAX + 1] = {
5345         [IFLA_INET6_ADDR_GEN_MODE]      = { .type = NLA_U8 },
5346         [IFLA_INET6_TOKEN]              = { .len = sizeof(struct in6_addr) },
5347 };
5348 
5349 static int inet6_validate_link_af(const struct net_device *dev,
5350                                   const struct nlattr *nla)
5351 {
5352         struct nlattr *tb[IFLA_INET6_MAX + 1];
5353 
5354         if (dev && !__in6_dev_get(dev))
5355                 return -EAFNOSUPPORT;
5356 
5357         return nla_parse_nested(tb, IFLA_INET6_MAX, nla, inet6_af_policy,
5358                                 NULL);
5359 }
5360 
5361 static int check_addr_gen_mode(int mode)
5362 {
5363         if (mode != IN6_ADDR_GEN_MODE_EUI64 &&
5364             mode != IN6_ADDR_GEN_MODE_NONE &&
5365             mode != IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5366             mode != IN6_ADDR_GEN_MODE_RANDOM)
5367                 return -EINVAL;
5368         return 1;
5369 }
5370 
5371 static int check_stable_privacy(struct inet6_dev *idev, struct net *net,
5372                                 int mode)
5373 {
5374         if (mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5375             !idev->cnf.stable_secret.initialized &&
5376             !net->ipv6.devconf_dflt->stable_secret.initialized)
5377                 return -EINVAL;
5378         return 1;
5379 }
5380 
5381 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla)
5382 {
5383         int err = -EINVAL;
5384         struct inet6_dev *idev = __in6_dev_get(dev);
5385         struct nlattr *tb[IFLA_INET6_MAX + 1];
5386 
5387         if (!idev)
5388                 return -EAFNOSUPPORT;
5389 
5390         if (nla_parse_nested(tb, IFLA_INET6_MAX, nla, NULL, NULL) < 0)
5391                 BUG();
5392 
5393         if (tb[IFLA_INET6_TOKEN]) {
5394                 err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]));
5395                 if (err)
5396                         return err;
5397         }
5398 
5399         if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
5400                 u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
5401 
5402                 if (check_addr_gen_mode(mode) < 0 ||
5403                     check_stable_privacy(idev, dev_net(dev), mode) < 0)
5404                         return -EINVAL;
5405 
5406                 idev->cnf.addr_gen_mode = mode;
5407                 err = 0;
5408         }
5409 
5410         return err;
5411 }
5412 
5413 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
5414                              u32 portid, u32 seq, int event, unsigned int flags)
5415 {
5416         struct net_device *dev = idev->dev;
5417         struct ifinfomsg *hdr;
5418         struct nlmsghdr *nlh;
5419         void *protoinfo;
5420 
5421         nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
5422         if (!nlh)
5423                 return -EMSGSIZE;
5424 
5425         hdr = nlmsg_data(nlh);
5426         hdr->ifi_family = AF_INET6;
5427         hdr->__ifi_pad = 0;
5428         hdr->ifi_type = dev->type;
5429         hdr->ifi_index = dev->ifindex;
5430         hdr->ifi_flags = dev_get_flags(dev);
5431         hdr->ifi_change = 0;
5432 
5433         if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
5434             (dev->addr_len &&
5435              nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
5436             nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
5437             (dev->ifindex != dev_get_iflink(dev) &&
5438              nla_put_u32(skb, IFLA_LINK, dev_get_iflink(dev))) ||
5439             nla_put_u8(skb, IFLA_OPERSTATE,
5440                        netif_running(dev) ? dev->operstate : IF_OPER_DOWN))
5441                 goto nla_put_failure;
5442         protoinfo = nla_nest_start(skb, IFLA_PROTINFO);
5443         if (!protoinfo)
5444                 goto nla_put_failure;
5445 
5446         if (inet6_fill_ifla6_attrs(skb, idev, 0) < 0)
5447                 goto nla_put_failure;
5448 
5449         nla_nest_end(skb, protoinfo);
5450         nlmsg_end(skb, nlh);
5451         return 0;
5452 
5453 nla_put_failure:
5454         nlmsg_cancel(skb, nlh);
5455         return -EMSGSIZE;
5456 }
5457 
5458 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
5459 {
5460         struct net *net = sock_net(skb->sk);
5461         int h, s_h;
5462         int idx = 0, s_idx;
5463         struct net_device *dev;
5464         struct inet6_dev *idev;
5465         struct hlist_head *head;
5466 
5467         s_h = cb->args[0];
5468         s_idx = cb->args[1];
5469 
5470         rcu_read_lock();
5471         for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
5472                 idx = 0;
5473                 head = &net->dev_index_head[h];
5474                 hlist_for_each_entry_rcu(dev, head, index_hlist) {
5475                         if (idx < s_idx)
5476                                 goto cont;
5477                         idev = __in6_dev_get(dev);
5478                         if (!idev)
5479                                 goto cont;
5480                         if (inet6_fill_ifinfo(skb, idev,
5481                                               NETLINK_CB(cb->skb).portid,
5482                                               cb->nlh->nlmsg_seq,
5483                                               RTM_NEWLINK, NLM_F_MULTI) < 0)
5484                                 goto out;
5485 cont:
5486                         idx++;
5487                 }
5488         }
5489 out:
5490         rcu_read_unlock();
5491         cb->args[1] = idx;
5492         cb->args[0] = h;
5493 
5494         return skb->len;
5495 }
5496 
5497 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
5498 {
5499         struct sk_buff *skb;
5500         struct net *net = dev_net(idev->dev);
5501         int err = -ENOBUFS;
5502 
5503         skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
5504         if (!skb)
5505                 goto errout;
5506 
5507         err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
5508         if (err < 0) {
5509                 /* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
5510                 WARN_ON(err == -EMSGSIZE);
5511                 kfree_skb(skb);
5512                 goto errout;
5513         }
5514         rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
5515         return;
5516 errout:
5517         if (err < 0)
5518                 rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
5519 }
5520 
5521 static inline size_t inet6_prefix_nlmsg_size(void)
5522 {
5523         return NLMSG_ALIGN(sizeof(struct prefixmsg))
5524                + nla_total_size(sizeof(struct in6_addr))
5525                + nla_total_size(sizeof(struct prefix_cacheinfo));
5526 }
5527 
5528 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
5529                              struct prefix_info *pinfo, u32 portid, u32 seq,
5530                              int event, unsigned int flags)
5531 {
5532         struct prefixmsg *pmsg;
5533         struct nlmsghdr *nlh;
5534         struct prefix_cacheinfo ci;
5535 
5536         nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
5537         if (!nlh)
5538                 return -EMSGSIZE;
5539 
5540         pmsg = nlmsg_data(nlh);
5541         pmsg->prefix_family = AF_INET6;
5542         pmsg->prefix_pad1 = 0;
5543         pmsg->prefix_pad2 = 0;
5544         pmsg->prefix_ifindex = idev->dev->ifindex;
5545         pmsg->prefix_len = pinfo->prefix_len;
5546         pmsg->prefix_type = pinfo->type;
5547         pmsg->prefix_pad3 = 0;
5548         pmsg->prefix_flags = 0;
5549         if (pinfo->onlink)
5550                 pmsg->prefix_flags |= IF_PREFIX_ONLINK;
5551         if (pinfo->autoconf)
5552                 pmsg->prefix_flags |= IF_PREFIX_AUTOCONF;
5553 
5554         if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
5555                 goto nla_put_failure;
5556         ci.preferred_time = ntohl(pinfo->prefered);
5557         ci.valid_time = ntohl(pinfo->valid);
5558         if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
5559                 goto nla_put_failure;
5560         nlmsg_end(skb, nlh);
5561         return 0;
5562 
5563 nla_put_failure:
5564         nlmsg_cancel(skb, nlh);
5565         return -EMSGSIZE;
5566 }
5567 
5568 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
5569                          struct prefix_info *pinfo)
5570 {
5571         struct sk_buff *skb;
5572         struct net *net = dev_net(idev->dev);
5573         int err = -ENOBUFS;
5574 
5575         skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
5576         if (!skb)
5577                 goto errout;
5578 
5579         err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
5580         if (err < 0) {
5581                 /* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
5582                 WARN_ON(err == -EMSGSIZE);
5583                 kfree_skb(skb);
5584                 goto errout;
5585         }
5586         rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
5587         return;
5588 errout:
5589         if (err < 0)
5590                 rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
5591 }
5592 
5593 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
5594 {
5595         struct net *net = dev_net(ifp->idev->dev);
5596 
5597         if (event)
5598                 ASSERT_RTNL();
5599 
5600         inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
5601 
5602         switch (event) {
5603         case RTM_NEWADDR:
5604                 /*
5605                  * If the address was optimistic
5606                  * we inserted the route at the start of
5607                  * our DAD process, so we don't need
5608                  * to do it again
5609                  */
5610                 if (!rcu_access_pointer(ifp->rt->rt6i_node))
5611                         ip6_ins_rt(ifp->rt);
5612                 if (ifp->idev->cnf.forwarding)
5613                         addrconf_join_anycast(ifp);
5614                 if (!ipv6_addr_any(&ifp->peer_addr))
5615                         addrconf_prefix_route(&ifp->peer_addr, 128,
5616                                               ifp->idev->dev, 0, 0);
5617                 break;
5618         case RTM_DELADDR:
5619                 if (ifp->idev->cnf.forwarding)
5620                         addrconf_leave_anycast(ifp);
5621                 addrconf_leave_solict(ifp->idev, &ifp->addr);
5622                 if (!ipv6_addr_any(&ifp->peer_addr)) {
5623                         struct rt6_info *rt;
5624 
5625                         rt = addrconf_get_prefix_route(&ifp->peer_addr, 128,
5626                                                        ifp->idev->dev, 0, 0);
5627                         if (rt)
5628                                 ip6_del_rt(rt);
5629                 }
5630                 if (ifp->rt) {
5631                         if (dst_hold_safe(&ifp->rt->dst))
5632                                 ip6_del_rt(ifp->rt);
5633                 }
5634                 rt_genid_bump_ipv6(net);
5635                 break;
5636         }
5637         atomic_inc(&net->ipv6.dev_addr_genid);
5638 }
5639 
5640 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
5641 {
5642         rcu_read_lock_bh();
5643         if (likely(ifp->idev->dead == 0))
5644                 __ipv6_ifa_notify(event, ifp);
5645         rcu_read_unlock_bh();
5646 }
5647 
5648 #ifdef CONFIG_SYSCTL
5649 
5650 static
5651 int addrconf_sysctl_forward(struct ctl_table *ctl, int write,
5652                            void __user *buffer, size_t *lenp, loff_t *ppos)
5653 {
5654         int *valp = ctl->data;
5655         int val = *valp;
5656         loff_t pos = *ppos;
5657         struct ctl_table lctl;
5658         int ret;
5659 
5660         /*
5661          * ctl->data points to idev->cnf.forwarding, we should
5662          * not modify it until we get the rtnl lock.
5663          */
5664         lctl = *ctl;
5665         lctl.data = &val;
5666 
5667         ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5668 
5669         if (write)
5670                 ret = addrconf_fixup_forwarding(ctl, valp, val);
5671         if (ret)
5672                 *ppos = pos;
5673         return ret;
5674 }
5675 
5676 static
5677 int addrconf_sysctl_mtu(struct ctl_table *ctl, int write,
5678                         void __user *buffer, size_t *lenp, loff_t *ppos)
5679 {
5680         struct inet6_dev *idev = ctl->extra1;
5681         int min_mtu = IPV6_MIN_MTU;
5682         struct ctl_table lctl;
5683 
5684         lctl = *ctl;
5685         lctl.extra1 = &min_mtu;
5686         lctl.extra2 = idev ? &idev->dev->mtu : NULL;
5687 
5688         return proc_dointvec_minmax(&lctl, write, buffer, lenp, ppos);
5689 }
5690 
5691 static void dev_disable_change(struct inet6_dev *idev)
5692 {
5693         struct netdev_notifier_info info;
5694 
5695         if (!idev || !idev->dev)
5696                 return;
5697 
5698         netdev_notifier_info_init(&info, idev->dev);
5699         if (idev->cnf.disable_ipv6)
5700                 addrconf_notify(NULL, NETDEV_DOWN, &info);
5701         else
5702                 addrconf_notify(NULL, NETDEV_UP, &info);
5703 }
5704 
5705 static void addrconf_disable_change(struct net *net, __s32 newf)
5706 {
5707         struct net_device *dev;
5708         struct inet6_dev *idev;
5709 
5710         for_each_netdev(net, dev) {
5711                 idev = __in6_dev_get(dev);
5712                 if (idev) {
5713                         int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
5714                         idev->cnf.disable_ipv6 = newf;
5715                         if (changed)
5716                                 dev_disable_change(idev);
5717                 }
5718         }
5719 }
5720 
5721 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
5722 {
5723         struct net *net;
5724         int old;
5725 
5726         if (!rtnl_trylock())
5727                 return restart_syscall();
5728 
5729         net = (struct net *)table->extra2;
5730         old = *p;
5731         *p = newf;
5732 
5733         if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
5734                 rtnl_unlock();
5735                 return 0;
5736         }
5737 
5738         if (p == &net->ipv6.devconf_all->disable_ipv6) {
5739                 net->ipv6.devconf_dflt->disable_ipv6 = newf;
5740                 addrconf_disable_change(net, newf);
5741         } else if ((!newf) ^ (!old))
5742                 dev_disable_change((struct inet6_dev *)table->extra1);
5743 
5744         rtnl_unlock();
5745         return 0;
5746 }
5747 
5748 static
5749 int addrconf_sysctl_disable(struct ctl_table *ctl, int write,
5750                             void __user *buffer, size_t *lenp, loff_t *ppos)
5751 {
5752         int *valp = ctl->data;
5753         int val = *valp;
5754         loff_t pos = *ppos;
5755         struct ctl_table lctl;
5756         int ret;
5757 
5758         /*
5759          * ctl->data points to idev->cnf.disable_ipv6, we should
5760          * not modify it until we get the rtnl lock.
5761          */
5762         lctl = *ctl;
5763         lctl.data = &val;
5764 
5765         ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5766 
5767         if (write)
5768                 ret = addrconf_disable_ipv6(ctl, valp, val);
5769         if (ret)
5770                 *ppos = pos;
5771         return ret;
5772 }
5773 
5774 static
5775 int addrconf_sysctl_proxy_ndp(struct ctl_table *ctl, int write,
5776                               void __user *buffer, size_t *lenp, loff_t *ppos)
5777 {
5778         int *valp = ctl->data;
5779         int ret;
5780         int old, new;
5781 
5782         old = *valp;
5783         ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
5784         new = *valp;
5785 
5786         if (write && old != new) {
5787                 struct net *net = ctl->extra2;
5788 
5789                 if (!rtnl_trylock())
5790                         return restart_syscall();
5791 
5792                 if (valp == &net->ipv6.devconf_dflt->proxy_ndp)
5793                         inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
5794                                                      NETCONFA_PROXY_NEIGH,
5795                                                      NETCONFA_IFINDEX_DEFAULT,
5796                                                      net->ipv6.devconf_dflt);
5797                 else if (valp == &net->ipv6.devconf_all->proxy_ndp)
5798