net/ipv6/addrconf.c

   1 /*
   2  *      IPv6 Address [auto]configuration
   3  *      Linux INET6 implementation
   4  *
   5  *      Authors:
   6  *      Pedro Roque             <roque@di.fc.ul.pt>
   7  *      Alexey Kuznetsov        <kuznet@ms2.inr.ac.ru>
   8  *
   9  *      This program is free software; you can redistribute it and/or
  10  *      modify it under the terms of the GNU General Public License
  11  *      as published by the Free Software Foundation; either version
  12  *      2 of the License, or (at your option) any later version.
  13  */
  14
  15 /*
  16  *      Changes:
  17  *
  18  *      Janos Farkas                    :       delete timer on ifdown
  19  *      <chexum@bankinf.banki.hu>
  20  *      Andi Kleen                      :       kill double kfree on module
  21  *                                              unload.
  22  *      Maciej W. Rozycki               :       FDDI support
  23  *      sekiya@USAGI                    :       Don't send too many RS
  24  *                                              packets.
  25  *      yoshfuji@USAGI                  :       Fixed interval between DAD
  26  *                                              packets.
  27  *      YOSHIFUJI Hideaki @USAGI        :       improved accuracy of
  28  *                                              address validation timer.
  29  *      YOSHIFUJI Hideaki @USAGI        :       Privacy Extensions (RFC3041)
  30  *                                              support.
  31  *      Yuji SEKIYA @USAGI              :       Don't assign a same IPv6
  32  *                                              address on a same interface.
  33  *      YOSHIFUJI Hideaki @USAGI        :       ARCnet support
  34  *      YOSHIFUJI Hideaki @USAGI        :       convert /proc/net/if_inet6 to
  35  *                                              seq_file.
  36  *      YOSHIFUJI Hideaki @USAGI        :       improved source address
  37  *                                              selection; consider scope,
  38  *                                              status etc.
  39  */
  40
  41 #include <linux/errno.h>
  42 #include <linux/types.h>
  43 #include <linux/kernel.h>
  44 #include <linux/socket.h>
  45 #include <linux/sockios.h>
  46 #include <linux/net.h>
  47 #include <linux/in6.h>
  48 #include <linux/netdevice.h>
  49 #include <linux/if_addr.h>
  50 #include <linux/if_arp.h>
  51 #include <linux/if_arcnet.h>
  52 #include <linux/if_infiniband.h>
  53 #include <linux/route.h>
  54 #include <linux/inetdevice.h>
  55 #include <linux/init.h>
  56 #include <linux/slab.h>
  57 #ifdef CONFIG_SYSCTL
  58 #include <linux/sysctl.h>
  59 #endif
  60 #include <linux/capability.h>
  61 #include <linux/delay.h>
  62 #include <linux/notifier.h>
  63 #include <linux/string.h>
  64
  65 #include <net/net_namespace.h>
  66 #include <net/sock.h>
  67 #include <net/snmp.h>
  68
  69 #include <net/ipv6.h>
  70 #include <net/protocol.h>
  71 #include <net/ndisc.h>
  72 #include <net/ip6_route.h>
  73 #include <net/addrconf.h>
  74 #include <net/tcp.h>
  75 #include <net/ip.h>
  76 #include <net/netlink.h>
  77 #include <net/pkt_sched.h>
  78 #include <linux/if_tunnel.h>
  79 #include <linux/rtnetlink.h>
  80
  81 #ifdef CONFIG_IPV6_PRIVACY
  82 #include <linux/random.h>
  83 #endif
  84
  85 #include <linux/uaccess.h>
  86 #include <asm/unaligned.h>
  87
  88 #include <linux/proc_fs.h>
  89 #include <linux/seq_file.h>
  90
  91 /* Set to 3 to get tracing... */
  92 #define ACONF_DEBUG 2
  93
  94 #if ACONF_DEBUG >= 3
  95 #define ADBG(x) printk x
  96 #else
  97 #define ADBG(x)
  98 #endif
  99
 100 #define INFINITY_LIFE_TIME      0xFFFFFFFF
 101
 102 static inline u32 cstamp_delta(unsigned long cstamp)
 103 {
 104         return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
 105 }
 106
 107 #define ADDRCONF_TIMER_FUZZ_MINUS       (HZ > 50 ? HZ/50 : 1)
 108 #define ADDRCONF_TIMER_FUZZ             (HZ / 4)
 109 #define ADDRCONF_TIMER_FUZZ_MAX         (HZ)
 110
 111 #ifdef CONFIG_SYSCTL
 112 static void addrconf_sysctl_register(struct inet6_dev *idev);
 113 static void addrconf_sysctl_unregister(struct inet6_dev *idev);
 114 #else
 115 static inline void addrconf_sysctl_register(struct inet6_dev *idev)
 116 {
 117 }
 118
 119 static inline void addrconf_sysctl_unregister(struct inet6_dev *idev)
 120 {
 121 }
 122 #endif
 123
 124 #ifdef CONFIG_IPV6_PRIVACY
 125 static int __ipv6_regen_rndid(struct inet6_dev *idev);
 126 static int __ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr);
 127 static void ipv6_regen_rndid(unsigned long data);
 128 #endif
 129
 130 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev);
 131 static int ipv6_count_addresses(struct inet6_dev *idev);
 132
 133 /*
 134  *      Configured unicast address hash table
 135  */
 136 static struct hlist_head inet6_addr_lst[IN6_ADDR_HSIZE];
 137 static DEFINE_SPINLOCK(addrconf_hash_lock);
 138
 139 static void addrconf_verify(unsigned long);
 140
 141 static DEFINE_TIMER(addr_chk_timer, addrconf_verify, 0, 0);
 142 static DEFINE_SPINLOCK(addrconf_verify_lock);
 143
 144 static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
 145 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
 146
 147 static void addrconf_type_change(struct net_device *dev,
 148                                  unsigned long event);
 149 static int addrconf_ifdown(struct net_device *dev, int how);
 150
 151 static void addrconf_dad_start(struct inet6_ifaddr *ifp, u32 flags);
 152 static void addrconf_dad_timer(unsigned long data);
 153 static void addrconf_dad_completed(struct inet6_ifaddr *ifp);
 154 static void addrconf_dad_run(struct inet6_dev *idev);
 155 static void addrconf_rs_timer(unsigned long data);
 156 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
 157 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
 158
 159 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
 160                                 struct prefix_info *pinfo);
 161 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
 162                                struct net_device *dev);
 163
 164 static ATOMIC_NOTIFIER_HEAD(inet6addr_chain);
 165
 166 static struct ipv6_devconf ipv6_devconf __read_mostly = {
 167         .forwarding             = 0,
 168         .hop_limit              = IPV6_DEFAULT_HOPLIMIT,
 169         .mtu6                   = IPV6_MIN_MTU,
 170         .accept_ra              = 1,
 171         .accept_redirects       = 1,
 172         .autoconf               = 1,
 173         .force_mld_version      = 0,
 174         .dad_transmits          = 1,
 175         .rtr_solicits           = MAX_RTR_SOLICITATIONS,
 176         .rtr_solicit_interval   = RTR_SOLICITATION_INTERVAL,
 177         .rtr_solicit_delay      = MAX_RTR_SOLICITATION_DELAY,
 178 #ifdef CONFIG_IPV6_PRIVACY
 179         .use_tempaddr           = 0,
 180         .temp_valid_lft         = TEMP_VALID_LIFETIME,
 181         .temp_prefered_lft      = TEMP_PREFERRED_LIFETIME,
 182         .regen_max_retry        = REGEN_MAX_RETRY,
 183         .max_desync_factor      = MAX_DESYNC_FACTOR,
 184 #endif
 185         .max_addresses          = IPV6_MAX_ADDRESSES,
 186         .accept_ra_defrtr       = 1,
 187         .accept_ra_pinfo        = 1,
 188 #ifdef CONFIG_IPV6_ROUTER_PREF
 189         .accept_ra_rtr_pref     = 1,
 190         .rtr_probe_interval     = 60 * HZ,
 191 #ifdef CONFIG_IPV6_ROUTE_INFO
 192         .accept_ra_rt_info_max_plen = 0,
 193 #endif
 194 #endif
 195         .proxy_ndp              = 0,
 196         .accept_source_route    = 0,    /* we do not accept RH0 by default. */
 197         .disable_ipv6           = 0,
 198         .accept_dad             = 1,
 199 };
 200
 201 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
 202         .forwarding             = 0,
 203         .hop_limit              = IPV6_DEFAULT_HOPLIMIT,
 204         .mtu6                   = IPV6_MIN_MTU,
 205         .accept_ra              = 1,
 206         .accept_redirects       = 1,
 207         .autoconf               = 1,
 208         .dad_transmits          = 1,
 209         .rtr_solicits           = MAX_RTR_SOLICITATIONS,
 210         .rtr_solicit_interval   = RTR_SOLICITATION_INTERVAL,
 211         .rtr_solicit_delay      = MAX_RTR_SOLICITATION_DELAY,
 212 #ifdef CONFIG_IPV6_PRIVACY
 213         .use_tempaddr           = 0,
 214         .temp_valid_lft         = TEMP_VALID_LIFETIME,
 215         .temp_prefered_lft      = TEMP_PREFERRED_LIFETIME,
 216         .regen_max_retry        = REGEN_MAX_RETRY,
 217         .max_desync_factor      = MAX_DESYNC_FACTOR,
 218 #endif
 219         .max_addresses          = IPV6_MAX_ADDRESSES,
 220         .accept_ra_defrtr       = 1,
 221         .accept_ra_pinfo        = 1,
 222 #ifdef CONFIG_IPV6_ROUTER_PREF
 223         .accept_ra_rtr_pref     = 1,
 224         .rtr_probe_interval     = 60 * HZ,
 225 #ifdef CONFIG_IPV6_ROUTE_INFO
 226         .accept_ra_rt_info_max_plen = 0,
 227 #endif
 228 #endif
 229         .proxy_ndp              = 0,
 230         .accept_source_route    = 0,    /* we do not accept RH0 by default. */
 231         .disable_ipv6           = 0,
 232         .accept_dad             = 1,
 233 };
 234
 235 /* IPv6 Wildcard Address and Loopback Address defined by RFC2553 */
 236 const struct in6_addr in6addr_any = IN6ADDR_ANY_INIT;
 237 const struct in6_addr in6addr_loopback = IN6ADDR_LOOPBACK_INIT;
 238 const struct in6_addr in6addr_linklocal_allnodes = IN6ADDR_LINKLOCAL_ALLNODES_INIT;
 239 const struct in6_addr in6addr_linklocal_allrouters = IN6ADDR_LINKLOCAL_ALLROUTERS_INIT;
 240
 241 /* Check if a valid qdisc is available */
 242 static inline bool addrconf_qdisc_ok(const struct net_device *dev)
 243 {
 244         return !qdisc_tx_is_noop(dev);
 245 }
 246
 247 /* Check if a route is valid prefix route */
 248 static inline int addrconf_is_prefix_route(const struct rt6_info *rt)
 249 {
 250         return (rt->rt6i_flags & (RTF_GATEWAY | RTF_DEFAULT)) == 0;
 251 }
 252
 253 static void addrconf_del_timer(struct inet6_ifaddr *ifp)
 254 {
 255         if (del_timer(&ifp->timer))
 256                 __in6_ifa_put(ifp);
 257 }
 258
 259 enum addrconf_timer_t {
 260         AC_NONE,
 261         AC_DAD,
 262         AC_RS,
 263 };
 264
 265 static void addrconf_mod_timer(struct inet6_ifaddr *ifp,
 266                                enum addrconf_timer_t what,
 267                                unsigned long when)
 268 {
 269         if (!del_timer(&ifp->timer))
 270                 in6_ifa_hold(ifp);
 271
 272         switch (what) {
 273         case AC_DAD:
 274                 ifp->timer.function = addrconf_dad_timer;
 275                 break;
 276         case AC_RS:
 277                 ifp->timer.function = addrconf_rs_timer;
 278                 break;
 279         default:
 280                 break;
 281         }
 282         ifp->timer.expires = jiffies + when;
 283         add_timer(&ifp->timer);
 284 }
 285
 286 static int snmp6_alloc_dev(struct inet6_dev *idev)
 287 {
 288         if (snmp_mib_init((void __percpu **)idev->stats.ipv6,
 289                           sizeof(struct ipstats_mib),
 290                           __alignof__(struct ipstats_mib)) < 0)
 291                 goto err_ip;
 292         if (snmp_mib_init((void __percpu **)idev->stats.icmpv6,
 293                           sizeof(struct icmpv6_mib),
 294                           __alignof__(struct icmpv6_mib)) < 0)
 295                 goto err_icmp;
 296         if (snmp_mib_init((void __percpu **)idev->stats.icmpv6msg,
 297                           sizeof(struct icmpv6msg_mib),
 298                           __alignof__(struct icmpv6msg_mib)) < 0)
 299                 goto err_icmpmsg;
 300
 301         return 0;
 302
 303 err_icmpmsg:
 304         snmp_mib_free((void __percpu **)idev->stats.icmpv6);
 305 err_icmp:
 306         snmp_mib_free((void __percpu **)idev->stats.ipv6);
 307 err_ip:
 308         return -ENOMEM;
 309 }
 310
 311 static void snmp6_free_dev(struct inet6_dev *idev)
 312 {
 313         snmp_mib_free((void __percpu **)idev->stats.icmpv6msg);
 314         snmp_mib_free((void __percpu **)idev->stats.icmpv6);
 315         snmp_mib_free((void __percpu **)idev->stats.ipv6);
 316 }
 317
 318 /* Nobody refers to this device, we may destroy it. */
 319
 320 static void in6_dev_finish_destroy_rcu(struct rcu_head *head)
 321 {
 322         struct inet6_dev *idev = container_of(head, struct inet6_dev, rcu);
 323         kfree(idev);
 324 }
 325
 326 void in6_dev_finish_destroy(struct inet6_dev *idev)
 327 {
 328         struct net_device *dev = idev->dev;
 329
 330         WARN_ON(!list_empty(&idev->addr_list));
 331         WARN_ON(idev->mc_list != NULL);
 332
 333 #ifdef NET_REFCNT_DEBUG
 334         printk(KERN_DEBUG "in6_dev_finish_destroy: %s\n", dev ? dev->name : "NIL");
 335 #endif
 336         dev_put(dev);
 337         if (!idev->dead) {
 338                 pr_warning("Freeing alive inet6 device %p\n", idev);
 339                 return;
 340         }
 341         snmp6_free_dev(idev);
 342         call_rcu(&idev->rcu, in6_dev_finish_destroy_rcu);
 343 }
 344
 345 EXPORT_SYMBOL(in6_dev_finish_destroy);
 346
 347 static struct inet6_dev * ipv6_add_dev(struct net_device *dev)
 348 {
 349         struct inet6_dev *ndev;
 350
 351         ASSERT_RTNL();
 352
 353         if (dev->mtu < IPV6_MIN_MTU)
 354                 return NULL;
 355
 356         ndev = kzalloc(sizeof(struct inet6_dev), GFP_KERNEL);
 357
 358         if (ndev == NULL)
 359                 return NULL;
 360
 361         rwlock_init(&ndev->lock);
 362         ndev->dev = dev;
 363         INIT_LIST_HEAD(&ndev->addr_list);
 364
 365         memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
 366         ndev->cnf.mtu6 = dev->mtu;
 367         ndev->cnf.sysctl = NULL;
 368         ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
 369         if (ndev->nd_parms == NULL) {
 370                 kfree(ndev);
 371                 return NULL;
 372         }
 373         if (ndev->cnf.forwarding)
 374                 dev_disable_lro(dev);
 375         /* We refer to the device */
 376         dev_hold(dev);
 377
 378         if (snmp6_alloc_dev(ndev) < 0) {
 379                 ADBG((KERN_WARNING
 380                         "%s(): cannot allocate memory for statistics; dev=%s.\n",
 381                         __func__, dev->name));
 382                 neigh_parms_release(&nd_tbl, ndev->nd_parms);
 383                 ndev->dead = 1;
 384                 in6_dev_finish_destroy(ndev);
 385                 return NULL;
 386         }
 387
 388         if (snmp6_register_dev(ndev) < 0) {
 389                 ADBG((KERN_WARNING
 390                         "%s(): cannot create /proc/net/dev_snmp6/%s\n",
 391                         __func__, dev->name));
 392                 neigh_parms_release(&nd_tbl, ndev->nd_parms);
 393                 ndev->dead = 1;
 394                 in6_dev_finish_destroy(ndev);
 395                 return NULL;
 396         }
 397
 398         /* One reference from device.  We must do this before
 399          * we invoke __ipv6_regen_rndid().
 400          */
 401         in6_dev_hold(ndev);
 402
 403         if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
 404                 ndev->cnf.accept_dad = -1;
 405
 406 #if defined(CONFIG_IPV6_SIT) || defined(CONFIG_IPV6_SIT_MODULE)
 407         if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
 408                 printk(KERN_INFO
 409                        "%s: Disabled Multicast RS\n",
 410                        dev->name);
 411                 ndev->cnf.rtr_solicits = 0;
 412         }
 413 #endif
 414
 415 #ifdef CONFIG_IPV6_PRIVACY
 416         INIT_LIST_HEAD(&ndev->tempaddr_list);
 417         setup_timer(&ndev->regen_timer, ipv6_regen_rndid, (unsigned long)ndev);
 418         if ((dev->flags&IFF_LOOPBACK) ||
 419             dev->type == ARPHRD_TUNNEL ||
 420             dev->type == ARPHRD_TUNNEL6 ||
 421             dev->type == ARPHRD_SIT ||
 422             dev->type == ARPHRD_NONE) {
 423                 printk(KERN_INFO
 424                        "%s: Disabled Privacy Extensions\n",
 425                        dev->name);
 426                 ndev->cnf.use_tempaddr = -1;
 427         } else {
 428                 in6_dev_hold(ndev);
 429                 ipv6_regen_rndid((unsigned long) ndev);
 430         }
 431 #endif
 432
 433         if (netif_running(dev) && addrconf_qdisc_ok(dev))
 434                 ndev->if_flags |= IF_READY;
 435
 436         ipv6_mc_init_dev(ndev);
 437         ndev->tstamp = jiffies;
 438         addrconf_sysctl_register(ndev);
 439         /* protected by rtnl_lock */
 440         rcu_assign_pointer(dev->ip6_ptr, ndev);
 441
 442         /* Join all-node multicast group */
 443         ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
 444
 445         return ndev;
 446 }
 447
 448 static struct inet6_dev * ipv6_find_idev(struct net_device *dev)
 449 {
 450         struct inet6_dev *idev;
 451
 452         ASSERT_RTNL();
 453
 454         idev = __in6_dev_get(dev);
 455         if (!idev) {
 456                 idev = ipv6_add_dev(dev);
 457                 if (!idev)
 458                         return NULL;
 459         }
 460
 461         if (dev->flags&IFF_UP)
 462                 ipv6_mc_up(idev);
 463         return idev;
 464 }
 465
 466 #ifdef CONFIG_SYSCTL
 467 static void dev_forward_change(struct inet6_dev *idev)
 468 {
 469         struct net_device *dev;
 470         struct inet6_ifaddr *ifa;
 471
 472         if (!idev)
 473                 return;
 474         dev = idev->dev;
 475         if (idev->cnf.forwarding)
 476                 dev_disable_lro(dev);
 477         if (dev && (dev->flags & IFF_MULTICAST)) {
 478                 if (idev->cnf.forwarding)
 479                         ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
 480                 else
 481                         ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
 482         }
 483
 484         list_for_each_entry(ifa, &idev->addr_list, if_list) {
 485                 if (ifa->flags&IFA_F_TENTATIVE)
 486                         continue;
 487                 if (idev->cnf.forwarding)
 488                         addrconf_join_anycast(ifa);
 489                 else
 490                         addrconf_leave_anycast(ifa);
 491         }
 492 }
 493
 494
 495 static void addrconf_forward_change(struct net *net, __s32 newf)
 496 {
 497         struct net_device *dev;
 498         struct inet6_dev *idev;
 499
 500         rcu_read_lock();
 501         for_each_netdev_rcu(net, dev) {
 502                 idev = __in6_dev_get(dev);
 503                 if (idev) {
 504                         int changed = (!idev->cnf.forwarding) ^ (!newf);
 505                         idev->cnf.forwarding = newf;
 506                         if (changed)
 507                                 dev_forward_change(idev);
 508                 }
 509         }
 510         rcu_read_unlock();
 511 }
 512
 513 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int old)
 514 {
 515         struct net *net;
 516
 517         net = (struct net *)table->extra2;
 518         if (p == &net->ipv6.devconf_dflt->forwarding)
 519                 return 0;
 520
 521         if (!rtnl_trylock()) {
 522                 /* Restore the original values before restarting */
 523                 *p = old;
 524                 return restart_syscall();
 525         }
 526
 527         if (p == &net->ipv6.devconf_all->forwarding) {
 528                 __s32 newf = net->ipv6.devconf_all->forwarding;
 529                 net->ipv6.devconf_dflt->forwarding = newf;
 530                 addrconf_forward_change(net, newf);
 531         } else if ((!*p) ^ (!old))
 532                 dev_forward_change((struct inet6_dev *)table->extra1);
 533         rtnl_unlock();
 534
 535         if (*p)
 536                 rt6_purge_dflt_routers(net);
 537         return 1;
 538 }
 539 #endif
 540
 541 static void inet6_ifa_finish_destroy_rcu(struct rcu_head *head)
 542 {
 543         struct inet6_ifaddr *ifp = container_of(head, struct inet6_ifaddr, rcu);
 544         kfree(ifp);
 545 }
 546
 547 /* Nobody refers to this ifaddr, destroy it */
 548 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
 549 {
 550         WARN_ON(!hlist_unhashed(&ifp->addr_lst));
 551
 552 #ifdef NET_REFCNT_DEBUG
 553         printk(KERN_DEBUG "inet6_ifa_finish_destroy\n");
 554 #endif
 555
 556         in6_dev_put(ifp->idev);
 557
 558         if (del_timer(&ifp->timer))
 559                 pr_notice("Timer is still running, when freeing ifa=%p\n", ifp);
 560
 561         if (ifp->state != INET6_IFADDR_STATE_DEAD) {
 562                 pr_warning("Freeing alive inet6 address %p\n", ifp);
 563                 return;
 564         }
 565         dst_release(&ifp->rt->dst);
 566
 567         call_rcu(&ifp->rcu, inet6_ifa_finish_destroy_rcu);
 568 }
 569
 570 static void
 571 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
 572 {
 573         struct list_head *p;
 574         int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
 575
 576         /*
 577          * Each device address list is sorted in order of scope -
 578          * global before linklocal.
 579          */
 580         list_for_each(p, &idev->addr_list) {
 581                 struct inet6_ifaddr *ifa
 582                         = list_entry(p, struct inet6_ifaddr, if_list);
 583                 if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
 584                         break;
 585         }
 586
 587         list_add_tail(&ifp->if_list, p);
 588 }
 589
 590 static u32 ipv6_addr_hash(const struct in6_addr *addr)
 591 {
 592         /*
 593          * We perform the hash function over the last 64 bits of the address
 594          * This will include the IEEE address token on links that support it.
 595          */
 596         return jhash_2words((__force u32)addr->s6_addr32[2],
 597                             (__force u32)addr->s6_addr32[3], 0)
 598                 & (IN6_ADDR_HSIZE - 1);
 599 }
 600
 601 /* On success it returns ifp with increased reference count */
 602
 603 static struct inet6_ifaddr *
 604 ipv6_add_addr(struct inet6_dev *idev, const struct in6_addr *addr, int pfxlen,
 605               int scope, u32 flags)
 606 {
 607         struct inet6_ifaddr *ifa = NULL;
 608         struct rt6_info *rt;
 609         unsigned int hash;
 610         int err = 0;
 611         int addr_type = ipv6_addr_type(addr);
 612
 613         if (addr_type == IPV6_ADDR_ANY ||
 614             addr_type & IPV6_ADDR_MULTICAST ||
 615             (!(idev->dev->flags & IFF_LOOPBACK) &&
 616              addr_type & IPV6_ADDR_LOOPBACK))
 617                 return ERR_PTR(-EADDRNOTAVAIL);
 618
 619         rcu_read_lock_bh();
 620         if (idev->dead) {
 621                 err = -ENODEV;                  /*XXX*/
 622                 goto out2;
 623         }
 624
 625         if (idev->cnf.disable_ipv6) {
 626                 err = -EACCES;
 627                 goto out2;
 628         }
 629
 630         spin_lock(&addrconf_hash_lock);
 631
 632         /* Ignore adding duplicate addresses on an interface */
 633         if (ipv6_chk_same_addr(dev_net(idev->dev), addr, idev->dev)) {
 634                 ADBG(("ipv6_add_addr: already assigned\n"));
 635                 err = -EEXIST;
 636                 goto out;
 637         }
 638
 639         ifa = kzalloc(sizeof(struct inet6_ifaddr), GFP_ATOMIC);
 640
 641         if (ifa == NULL) {
 642                 ADBG(("ipv6_add_addr: malloc failed\n"));
 643                 err = -ENOBUFS;
 644                 goto out;
 645         }
 646
 647         rt = addrconf_dst_alloc(idev, addr, 0);
 648         if (IS_ERR(rt)) {
 649                 err = PTR_ERR(rt);
 650                 goto out;
 651         }
 652
 653         ipv6_addr_copy(&ifa->addr, addr);
 654
 655         spin_lock_init(&ifa->lock);
 656         spin_lock_init(&ifa->state_lock);
 657         init_timer(&ifa->timer);
 658         INIT_HLIST_NODE(&ifa->addr_lst);
 659         ifa->timer.data = (unsigned long) ifa;
 660         ifa->scope = scope;
 661         ifa->prefix_len = pfxlen;
 662         ifa->flags = flags | IFA_F_TENTATIVE;
 663         ifa->cstamp = ifa->tstamp = jiffies;
 664
 665         ifa->rt = rt;
 666
 667         /*
 668          * part one of RFC 4429, section 3.3
 669          * We should not configure an address as
 670          * optimistic if we do not yet know the link
 671          * layer address of our nexhop router
 672          */
 673
 674         if (rt->rt6i_nexthop == NULL)
 675                 ifa->flags &= ~IFA_F_OPTIMISTIC;
 676
 677         ifa->idev = idev;
 678         in6_dev_hold(idev);
 679         /* For caller */
 680         in6_ifa_hold(ifa);
 681
 682         /* Add to big hash table */
 683         hash = ipv6_addr_hash(addr);
 684
 685         hlist_add_head_rcu(&ifa->addr_lst, &inet6_addr_lst[hash]);
 686         spin_unlock(&addrconf_hash_lock);
 687
 688         write_lock(&idev->lock);
 689         /* Add to inet6_dev unicast addr list. */
 690         ipv6_link_dev_addr(idev, ifa);
 691
 692 #ifdef CONFIG_IPV6_PRIVACY
 693         if (ifa->flags&IFA_F_TEMPORARY) {
 694                 list_add(&ifa->tmp_list, &idev->tempaddr_list);
 695                 in6_ifa_hold(ifa);
 696         }
 697 #endif
 698
 699         in6_ifa_hold(ifa);
 700         write_unlock(&idev->lock);
 701 out2:
 702         rcu_read_unlock_bh();
 703
 704         if (likely(err == 0))
 705                 atomic_notifier_call_chain(&inet6addr_chain, NETDEV_UP, ifa);
 706         else {
 707                 kfree(ifa);
 708                 ifa = ERR_PTR(err);
 709         }
 710
 711         return ifa;
 712 out:
 713         spin_unlock(&addrconf_hash_lock);
 714         goto out2;
 715 }
 716
 717 /* This function wants to get referenced ifp and releases it before return */
 718
 719 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
 720 {
 721         struct inet6_ifaddr *ifa, *ifn;
 722         struct inet6_dev *idev = ifp->idev;
 723         int state;
 724         int hash;
 725         int deleted = 0, onlink = 0;
 726         unsigned long expires = jiffies;
 727
 728         hash = ipv6_addr_hash(&ifp->addr);
 729
 730         spin_lock_bh(&ifp->state_lock);
 731         state = ifp->state;
 732         ifp->state = INET6_IFADDR_STATE_DEAD;
 733         spin_unlock_bh(&ifp->state_lock);
 734
 735         if (state == INET6_IFADDR_STATE_DEAD)
 736                 goto out;
 737
 738         spin_lock_bh(&addrconf_hash_lock);
 739         hlist_del_init_rcu(&ifp->addr_lst);
 740         spin_unlock_bh(&addrconf_hash_lock);
 741
 742         write_lock_bh(&idev->lock);
 743 #ifdef CONFIG_IPV6_PRIVACY
 744         if (ifp->flags&IFA_F_TEMPORARY) {
 745                 list_del(&ifp->tmp_list);
 746                 if (ifp->ifpub) {
 747                         in6_ifa_put(ifp->ifpub);
 748                         ifp->ifpub = NULL;
 749                 }
 750                 __in6_ifa_put(ifp);
 751         }
 752 #endif
 753
 754         list_for_each_entry_safe(ifa, ifn, &idev->addr_list, if_list) {
 755                 if (ifa == ifp) {
 756                         list_del_init(&ifp->if_list);
 757                         __in6_ifa_put(ifp);
 758
 759                         if (!(ifp->flags & IFA_F_PERMANENT) || onlink > 0)
 760                                 break;
 761                         deleted = 1;
 762                         continue;
 763                 } else if (ifp->flags & IFA_F_PERMANENT) {
 764                         if (ipv6_prefix_equal(&ifa->addr, &ifp->addr,
 765                                               ifp->prefix_len)) {
 766                                 if (ifa->flags & IFA_F_PERMANENT) {
 767                                         onlink = 1;
 768                                         if (deleted)
 769                                                 break;
 770                                 } else {
 771                                         unsigned long lifetime;
 772
 773                                         if (!onlink)
 774                                                 onlink = -1;
 775
 776                                         spin_lock(&ifa->lock);
 777
 778                                         lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
 779                                         /*
 780                                          * Note: Because this address is
 781                                          * not permanent, lifetime <
 782                                          * LONG_MAX / HZ here.
 783                                          */
 784                                         if (time_before(expires,
 785                                                         ifa->tstamp + lifetime * HZ))
 786                                                 expires = ifa->tstamp + lifetime * HZ;
 787                                         spin_unlock(&ifa->lock);
 788                                 }
 789                         }
 790                 }
 791         }
 792         write_unlock_bh(&idev->lock);
 793
 794         addrconf_del_timer(ifp);
 795
 796         ipv6_ifa_notify(RTM_DELADDR, ifp);
 797
 798         atomic_notifier_call_chain(&inet6addr_chain, NETDEV_DOWN, ifp);
 799
 800         /*
 801          * Purge or update corresponding prefix
 802          *
 803          * 1) we don't purge prefix here if address was not permanent.
 804          *    prefix is managed by its own lifetime.
 805          * 2) if there're no addresses, delete prefix.
 806          * 3) if there're still other permanent address(es),
 807          *    corresponding prefix is still permanent.
 808          * 4) otherwise, update prefix lifetime to the
 809          *    longest valid lifetime among the corresponding
 810          *    addresses on the device.
 811          *    Note: subsequent RA will update lifetime.
 812          *
 813          * --yoshfuji
 814          */
 815         if ((ifp->flags & IFA_F_PERMANENT) && onlink < 1) {
 816                 struct in6_addr prefix;
 817                 struct rt6_info *rt;
 818                 struct net *net = dev_net(ifp->idev->dev);
 819                 ipv6_addr_prefix(&prefix, &ifp->addr, ifp->prefix_len);
 820                 rt = rt6_lookup(net, &prefix, NULL, ifp->idev->dev->ifindex, 1);
 821
 822                 if (rt && addrconf_is_prefix_route(rt)) {
 823                         if (onlink == 0) {
 824                                 ip6_del_rt(rt);
 825                                 rt = NULL;
 826                         } else if (!(rt->rt6i_flags & RTF_EXPIRES)) {
 827                                 rt->rt6i_expires = expires;
 828                                 rt->rt6i_flags |= RTF_EXPIRES;
 829                         }
 830                 }
 831                 dst_release(&rt->dst);
 832         }
 833
 834 out:
 835         in6_ifa_put(ifp);
 836 }
 837
 838 #ifdef CONFIG_IPV6_PRIVACY
 839 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp, struct inet6_ifaddr *ift)
 840 {
 841         struct inet6_dev *idev = ifp->idev;
 842         struct in6_addr addr, *tmpaddr;
 843         unsigned long tmp_prefered_lft, tmp_valid_lft, tmp_cstamp, tmp_tstamp, age;
 844         unsigned long regen_advance;
 845         int tmp_plen;
 846         int ret = 0;
 847         int max_addresses;
 848         u32 addr_flags;
 849
 850         write_lock(&idev->lock);
 851         if (ift) {
 852                 spin_lock_bh(&ift->lock);
 853                 memcpy(&addr.s6_addr[8], &ift->addr.s6_addr[8], 8);
 854                 spin_unlock_bh(&ift->lock);
 855                 tmpaddr = &addr;
 856         } else {
 857                 tmpaddr = NULL;
 858         }
 859 retry:
 860         in6_dev_hold(idev);
 861         if (idev->cnf.use_tempaddr <= 0) {
 862                 write_unlock(&idev->lock);
 863                 printk(KERN_INFO
 864                         "ipv6_create_tempaddr(): use_tempaddr is disabled.\n");
 865                 in6_dev_put(idev);
 866                 ret = -1;
 867                 goto out;
 868         }
 869         spin_lock_bh(&ifp->lock);
 870         if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
 871                 idev->cnf.use_tempaddr = -1;    /*XXX*/
 872                 spin_unlock_bh(&ifp->lock);
 873                 write_unlock(&idev->lock);
 874                 printk(KERN_WARNING
 875                         "ipv6_create_tempaddr(): regeneration time exceeded. disabled temporary address support.\n");
 876                 in6_dev_put(idev);
 877                 ret = -1;
 878                 goto out;
 879         }
 880         in6_ifa_hold(ifp);
 881         memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
 882         if (__ipv6_try_regen_rndid(idev, tmpaddr) < 0) {
 883                 spin_unlock_bh(&ifp->lock);
 884                 write_unlock(&idev->lock);
 885                 printk(KERN_WARNING
 886                         "ipv6_create_tempaddr(): regeneration of randomized interface id failed.\n");
 887                 in6_ifa_put(ifp);
 888                 in6_dev_put(idev);
 889                 ret = -1;
 890                 goto out;
 891         }
 892         memcpy(&addr.s6_addr[8], idev->rndid, 8);
 893         age = (jiffies - ifp->tstamp) / HZ;
 894         tmp_valid_lft = min_t(__u32,
 895                               ifp->valid_lft,
 896                               idev->cnf.temp_valid_lft + age);
 897         tmp_prefered_lft = min_t(__u32,
 898                                  ifp->prefered_lft,
 899                                  idev->cnf.temp_prefered_lft + age -
 900                                  idev->cnf.max_desync_factor);
 901         tmp_plen = ifp->prefix_len;
 902         max_addresses = idev->cnf.max_addresses;
 903         tmp_cstamp = ifp->cstamp;
 904         tmp_tstamp = ifp->tstamp;
 905         spin_unlock_bh(&ifp->lock);
 906
 907         regen_advance = idev->cnf.regen_max_retry *
 908                         idev->cnf.dad_transmits *
 909                         idev->nd_parms->retrans_time / HZ;
 910         write_unlock(&idev->lock);
 911
 912         /* A temporary address is created only if this calculated Preferred
 913          * Lifetime is greater than REGEN_ADVANCE time units.  In particular,
 914          * an implementation must not create a temporary address with a zero
 915          * Preferred Lifetime.
 916          */
 917         if (tmp_prefered_lft <= regen_advance) {
 918                 in6_ifa_put(ifp);
 919                 in6_dev_put(idev);
 920                 ret = -1;
 921                 goto out;
 922         }
 923
 924         addr_flags = IFA_F_TEMPORARY;
 925         /* set in addrconf_prefix_rcv() */
 926         if (ifp->flags & IFA_F_OPTIMISTIC)
 927                 addr_flags |= IFA_F_OPTIMISTIC;
 928
 929         ift = !max_addresses ||
 930               ipv6_count_addresses(idev) < max_addresses ?
 931                 ipv6_add_addr(idev, &addr, tmp_plen,
 932                               ipv6_addr_type(&addr)&IPV6_ADDR_SCOPE_MASK,
 933                               addr_flags) : NULL;
 934         if (!ift || IS_ERR(ift)) {
 935                 in6_ifa_put(ifp);
 936                 in6_dev_put(idev);
 937                 printk(KERN_INFO
 938                         "ipv6_create_tempaddr(): retry temporary address regeneration.\n");
 939                 tmpaddr = &addr;
 940                 write_lock(&idev->lock);
 941                 goto retry;
 942         }
 943
 944         spin_lock_bh(&ift->lock);
 945         ift->ifpub = ifp;
 946         ift->valid_lft = tmp_valid_lft;
 947         ift->prefered_lft = tmp_prefered_lft;
 948         ift->cstamp = tmp_cstamp;
 949         ift->tstamp = tmp_tstamp;
 950         spin_unlock_bh(&ift->lock);
 951
 952         addrconf_dad_start(ift, 0);
 953         in6_ifa_put(ift);
 954         in6_dev_put(idev);
 955 out:
 956         return ret;
 957 }
 958 #endif
 959
 960 /*
 961  *      Choose an appropriate source address (RFC3484)
 962  */
 963 enum {
 964         IPV6_SADDR_RULE_INIT = 0,
 965         IPV6_SADDR_RULE_LOCAL,
 966         IPV6_SADDR_RULE_SCOPE,
 967         IPV6_SADDR_RULE_PREFERRED,
 968 #ifdef CONFIG_IPV6_MIP6
 969         IPV6_SADDR_RULE_HOA,
 970 #endif
 971         IPV6_SADDR_RULE_OIF,
 972         IPV6_SADDR_RULE_LABEL,
 973 #ifdef CONFIG_IPV6_PRIVACY
 974         IPV6_SADDR_RULE_PRIVACY,
 975 #endif
 976         IPV6_SADDR_RULE_ORCHID,
 977         IPV6_SADDR_RULE_PREFIX,
 978         IPV6_SADDR_RULE_MAX
 979 };
 980
 981 struct ipv6_saddr_score {
 982         int                     rule;
 983         int                     addr_type;
 984         struct inet6_ifaddr     *ifa;
 985         DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
 986         int                     scopedist;
 987         int                     matchlen;
 988 };
 989
 990 struct ipv6_saddr_dst {
 991         const struct in6_addr *addr;
 992         int ifindex;
 993         int scope;
 994         int label;
 995         unsigned int prefs;
 996 };
 997
 998 static inline int ipv6_saddr_preferred(int type)
 999 {
1000         if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1001                 return 1;
1002         return 0;
1003 }
1004
1005 static int ipv6_get_saddr_eval(struct net *net,
1006                                struct ipv6_saddr_score *score,
1007                                struct ipv6_saddr_dst *dst,
1008                                int i)
1009 {
1010         int ret;
1011
1012         if (i <= score->rule) {
1013                 switch (i) {
1014                 case IPV6_SADDR_RULE_SCOPE:
1015                         ret = score->scopedist;
1016                         break;
1017                 case IPV6_SADDR_RULE_PREFIX:
1018                         ret = score->matchlen;
1019                         break;
1020                 default:
1021                         ret = !!test_bit(i, score->scorebits);
1022                 }
1023                 goto out;
1024         }
1025
1026         switch (i) {
1027         case IPV6_SADDR_RULE_INIT:
1028                 /* Rule 0: remember if hiscore is not ready yet */
1029                 ret = !!score->ifa;
1030                 break;
1031         case IPV6_SADDR_RULE_LOCAL:
1032                 /* Rule 1: Prefer same address */
1033                 ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1034                 break;
1035         case IPV6_SADDR_RULE_SCOPE:
1036                 /* Rule 2: Prefer appropriate scope
1037                  *
1038                  *      ret
1039                  *       ^
1040                  *    -1 |  d 15
1041                  *    ---+--+-+---> scope
1042                  *       |
1043                  *       |             d is scope of the destination.
1044                  *  B-d  |  \
1045                  *       |   \      <- smaller scope is better if
1046                  *  B-15 |    \        if scope is enough for destinaion.
1047                  *       |             ret = B - scope (-1 <= scope >= d <= 15).
1048                  * d-C-1 | /
1049                  *       |/         <- greater is better
1050                  *   -C  /             if scope is not enough for destination.
1051                  *      /|             ret = scope - C (-1 <= d < scope <= 15).
1052                  *
1053                  * d - C - 1 < B -15 (for all -1 <= d <= 15).
1054                  * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1055                  * Assume B = 0 and we get C > 29.
1056                  */
1057                 ret = __ipv6_addr_src_scope(score->addr_type);
1058                 if (ret >= dst->scope)
1059                         ret = -ret;
1060                 else
1061                         ret -= 128;     /* 30 is enough */
1062                 score->scopedist = ret;
1063                 break;
1064         case IPV6_SADDR_RULE_PREFERRED:
1065                 /* Rule 3: Avoid deprecated and optimistic addresses */
1066                 ret = ipv6_saddr_preferred(score->addr_type) ||
1067                       !(score->ifa->flags & (IFA_F_DEPRECATED|IFA_F_OPTIMISTIC));
1068                 break;
1069 #ifdef CONFIG_IPV6_MIP6
1070         case IPV6_SADDR_RULE_HOA:
1071             {
1072                 /* Rule 4: Prefer home address */
1073                 int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1074                 ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1075                 break;
1076             }
1077 #endif
1078         case IPV6_SADDR_RULE_OIF:
1079                 /* Rule 5: Prefer outgoing interface */
1080                 ret = (!dst->ifindex ||
1081                        dst->ifindex == score->ifa->idev->dev->ifindex);
1082                 break;
1083         case IPV6_SADDR_RULE_LABEL:
1084                 /* Rule 6: Prefer matching label */
1085                 ret = ipv6_addr_label(net,
1086                                       &score->ifa->addr, score->addr_type,
1087                                       score->ifa->idev->dev->ifindex) == dst->label;
1088                 break;
1089 #ifdef CONFIG_IPV6_PRIVACY
1090         case IPV6_SADDR_RULE_PRIVACY:
1091             {
1092                 /* Rule 7: Prefer public address
1093                  * Note: prefer temprary address if use_tempaddr >= 2
1094                  */
1095                 int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1096                                 !!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1097                                 score->ifa->idev->cnf.use_tempaddr >= 2;
1098                 ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1099                 break;
1100             }
1101 #endif
1102         case IPV6_SADDR_RULE_ORCHID:
1103                 /* Rule 8-: Prefer ORCHID vs ORCHID or
1104                  *          non-ORCHID vs non-ORCHID
1105                  */
1106                 ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1107                         ipv6_addr_orchid(dst->addr));
1108                 break;
1109         case IPV6_SADDR_RULE_PREFIX:
1110                 /* Rule 8: Use longest matching prefix */
1111                 score->matchlen = ret = ipv6_addr_diff(&score->ifa->addr,
1112                                                        dst->addr);
1113                 break;
1114         default:
1115                 ret = 0;
1116         }
1117
1118         if (ret)
1119                 __set_bit(i, score->scorebits);
1120         score->rule = i;
1121 out:
1122         return ret;
1123 }
1124
1125 int ipv6_dev_get_saddr(struct net *net, struct net_device *dst_dev,
1126                        const struct in6_addr *daddr, unsigned int prefs,
1127                        struct in6_addr *saddr)
1128 {
1129         struct ipv6_saddr_score scores[2],
1130                                 *score = &scores[0], *hiscore = &scores[1];
1131         struct ipv6_saddr_dst dst;
1132         struct net_device *dev;
1133         int dst_type;
1134
1135         dst_type = __ipv6_addr_type(daddr);
1136         dst.addr = daddr;
1137         dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1138         dst.scope = __ipv6_addr_src_scope(dst_type);
1139         dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1140         dst.prefs = prefs;
1141
1142         hiscore->rule = -1;
1143         hiscore->ifa = NULL;
1144
1145         rcu_read_lock();
1146
1147         for_each_netdev_rcu(net, dev) {
1148                 struct inet6_dev *idev;
1149
1150                 /* Candidate Source Address (section 4)
1151                  *  - multicast and link-local destination address,
1152                  *    the set of candidate source address MUST only
1153                  *    include addresses assigned to interfaces
1154                  *    belonging to the same link as the outgoing
1155                  *    interface.
1156                  * (- For site-local destination addresses, the
1157                  *    set of candidate source addresses MUST only
1158                  *    include addresses assigned to interfaces
1159                  *    belonging to the same site as the outgoing
1160                  *    interface.)
1161                  */
1162                 if (((dst_type & IPV6_ADDR_MULTICAST) ||
1163                      dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL) &&
1164                     dst.ifindex && dev->ifindex != dst.ifindex)
1165                         continue;
1166
1167                 idev = __in6_dev_get(dev);
1168                 if (!idev)
1169                         continue;
1170
1171                 read_lock_bh(&idev->lock);
1172                 list_for_each_entry(score->ifa, &idev->addr_list, if_list) {
1173                         int i;
1174
1175                         /*
1176                          * - Tentative Address (RFC2462 section 5.4)
1177                          *  - A tentative address is not considered
1178                          *    "assigned to an interface" in the traditional
1179                          *    sense, unless it is also flagged as optimistic.
1180                          * - Candidate Source Address (section 4)
1181                          *  - In any case, anycast addresses, multicast
1182                          *    addresses, and the unspecified address MUST
1183                          *    NOT be included in a candidate set.
1184                          */
1185                         if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1186                             (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1187                                 continue;
1188
1189                         score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1190
1191                         if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1192                                      score->addr_type & IPV6_ADDR_MULTICAST)) {
1193                                 LIMIT_NETDEBUG(KERN_DEBUG
1194                                                "ADDRCONF: unspecified / multicast address "
1195                                                "assigned as unicast address on %s",
1196                                                dev->name);
1197                                 continue;
1198                         }
1199
1200                         score->rule = -1;
1201                         bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1202
1203                         for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1204                                 int minihiscore, miniscore;
1205
1206                                 minihiscore = ipv6_get_saddr_eval(net, hiscore, &dst, i);
1207                                 miniscore = ipv6_get_saddr_eval(net, score, &dst, i);
1208
1209                                 if (minihiscore > miniscore) {
1210                                         if (i == IPV6_SADDR_RULE_SCOPE &&
1211                                             score->scopedist > 0) {
1212                                                 /*
1213                                                  * special case:
1214                                                  * each remaining entry
1215                                                  * has too small (not enough)
1216                                                  * scope, because ifa entries
1217                                                  * are sorted by their scope
1218                                                  * values.
1219                                                  */
1220                                                 goto try_nextdev;
1221                                         }
1222                                         break;
1223                                 } else if (minihiscore < miniscore) {
1224                                         if (hiscore->ifa)
1225                                                 in6_ifa_put(hiscore->ifa);
1226
1227                                         in6_ifa_hold(score->ifa);
1228
1229                                         swap(hiscore, score);
1230
1231                                         /* restore our iterator */
1232                                         score->ifa = hiscore->ifa;
1233
1234                                         break;
1235                                 }
1236                         }
1237                 }
1238 try_nextdev:
1239                 read_unlock_bh(&idev->lock);
1240         }
1241         rcu_read_unlock();
1242
1243         if (!hiscore->ifa)
1244                 return -EADDRNOTAVAIL;
1245
1246         ipv6_addr_copy(saddr, &hiscore->ifa->addr);
1247         in6_ifa_put(hiscore->ifa);
1248         return 0;
1249 }
1250 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1251
1252 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1253                     unsigned char banned_flags)
1254 {
1255         struct inet6_dev *idev;
1256         int err = -EADDRNOTAVAIL;
1257
1258         rcu_read_lock();
1259         idev = __in6_dev_get(dev);
1260         if (idev) {
1261                 struct inet6_ifaddr *ifp;
1262
1263                 read_lock_bh(&idev->lock);
1264                 list_for_each_entry(ifp, &idev->addr_list, if_list) {
1265                         if (ifp->scope == IFA_LINK &&
1266                             !(ifp->flags & banned_flags)) {
1267                                 ipv6_addr_copy(addr, &ifp->addr);
1268                                 err = 0;
1269                                 break;
1270                         }
1271                 }
1272                 read_unlock_bh(&idev->lock);
1273         }
1274         rcu_read_unlock();
1275         return err;
1276 }
1277
1278 static int ipv6_count_addresses(struct inet6_dev *idev)
1279 {
1280         int cnt = 0;
1281         struct inet6_ifaddr *ifp;
1282
1283         read_lock_bh(&idev->lock);
1284         list_for_each_entry(ifp, &idev->addr_list, if_list)
1285                 cnt++;
1286         read_unlock_bh(&idev->lock);
1287         return cnt;
1288 }
1289
1290 int ipv6_chk_addr(struct net *net, struct in6_addr *addr,
1291                   struct net_device *dev, int strict)
1292 {
1293         struct inet6_ifaddr *ifp;
1294         struct hlist_node *node;
1295         unsigned int hash = ipv6_addr_hash(addr);
1296
1297         rcu_read_lock_bh();
1298         hlist_for_each_entry_rcu(ifp, node, &inet6_addr_lst[hash], addr_lst) {
1299                 if (!net_eq(dev_net(ifp->idev->dev), net))
1300                         continue;
1301                 if (ipv6_addr_equal(&ifp->addr, addr) &&
1302                     !(ifp->flags&IFA_F_TENTATIVE) &&
1303                     (dev == NULL || ifp->idev->dev == dev ||
1304                      !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1305                         rcu_read_unlock_bh();
1306                         return 1;
1307                 }
1308         }
1309
1310         rcu_read_unlock_bh();
1311         return 0;
1312 }
1313 EXPORT_SYMBOL(ipv6_chk_addr);
1314
1315 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
1316                                struct net_device *dev)
1317 {
1318         unsigned int hash = ipv6_addr_hash(addr);
1319         struct inet6_ifaddr *ifp;
1320         struct hlist_node *node;
1321
1322         hlist_for_each_entry(ifp, node, &inet6_addr_lst[hash], addr_lst) {
1323                 if (!net_eq(dev_net(ifp->idev->dev), net))
1324                         continue;
1325                 if (ipv6_addr_equal(&ifp->addr, addr)) {
1326                         if (dev == NULL || ifp->idev->dev == dev)
1327                                 return true;
1328                 }
1329         }
1330         return false;
1331 }
1332
1333 int ipv6_chk_prefix(struct in6_addr *addr, struct net_device *dev)
1334 {
1335         struct inet6_dev *idev;
1336         struct inet6_ifaddr *ifa;
1337         int     onlink;
1338
1339         onlink = 0;
1340         rcu_read_lock();
1341         idev = __in6_dev_get(dev);
1342         if (idev) {
1343                 read_lock_bh(&idev->lock);
1344                 list_for_each_entry(ifa, &idev->addr_list, if_list) {
1345                         onlink = ipv6_prefix_equal(addr, &ifa->addr,
1346                                                    ifa->prefix_len);
1347                         if (onlink)
1348                                 break;
1349                 }
1350                 read_unlock_bh(&idev->lock);
1351         }
1352         rcu_read_unlock();
1353         return onlink;
1354 }
1355
1356 EXPORT_SYMBOL(ipv6_chk_prefix);
1357
1358 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
1359                                      struct net_device *dev, int strict)
1360 {
1361         struct inet6_ifaddr *ifp, *result = NULL;
1362         unsigned int hash = ipv6_addr_hash(addr);
1363         struct hlist_node *node;
1364
1365         rcu_read_lock_bh();
1366         hlist_for_each_entry_rcu_bh(ifp, node, &inet6_addr_lst[hash], addr_lst) {
1367                 if (!net_eq(dev_net(ifp->idev->dev), net))
1368                         continue;
1369                 if (ipv6_addr_equal(&ifp->addr, addr)) {
1370                         if (dev == NULL || ifp->idev->dev == dev ||
1371                             !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
1372                                 result = ifp;
1373                                 in6_ifa_hold(ifp);
1374                                 break;
1375                         }
1376                 }
1377         }
1378         rcu_read_unlock_bh();
1379
1380         return result;
1381 }
1382
1383 /* Gets referenced address, destroys ifaddr */
1384
1385 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
1386 {
1387         if (ifp->flags&IFA_F_PERMANENT) {
1388                 spin_lock_bh(&ifp->lock);
1389                 addrconf_del_timer(ifp);
1390                 ifp->flags |= IFA_F_TENTATIVE;
1391                 if (dad_failed)
1392                         ifp->flags |= IFA_F_DADFAILED;
1393                 spin_unlock_bh(&ifp->lock);
1394                 if (dad_failed)
1395                         ipv6_ifa_notify(0, ifp);
1396                 in6_ifa_put(ifp);
1397 #ifdef CONFIG_IPV6_PRIVACY
1398         } else if (ifp->flags&IFA_F_TEMPORARY) {
1399                 struct inet6_ifaddr *ifpub;
1400                 spin_lock_bh(&ifp->lock);
1401                 ifpub = ifp->ifpub;
1402                 if (ifpub) {
1403                         in6_ifa_hold(ifpub);
1404                         spin_unlock_bh(&ifp->lock);
1405                         ipv6_create_tempaddr(ifpub, ifp);
1406                         in6_ifa_put(ifpub);
1407                 } else {
1408                         spin_unlock_bh(&ifp->lock);
1409                 }
1410                 ipv6_del_addr(ifp);
1411 #endif
1412         } else
1413                 ipv6_del_addr(ifp);
1414 }
1415
1416 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
1417 {
1418         int err = -ENOENT;
1419
1420         spin_lock(&ifp->state_lock);
1421         if (ifp->state == INET6_IFADDR_STATE_DAD) {
1422                 ifp->state = INET6_IFADDR_STATE_POSTDAD;
1423                 err = 0;
1424         }
1425         spin_unlock(&ifp->state_lock);
1426
1427         return err;
1428 }
1429
1430 void addrconf_dad_failure(struct inet6_ifaddr *ifp)
1431 {
1432         struct inet6_dev *idev = ifp->idev;
1433
1434         if (addrconf_dad_end(ifp)) {
1435                 in6_ifa_put(ifp);
1436                 return;
1437         }
1438
1439         if (net_ratelimit())
1440                 printk(KERN_INFO "%s: IPv6 duplicate address %pI6c detected!\n",
1441                         ifp->idev->dev->name, &ifp->addr);
1442
1443         if (idev->cnf.accept_dad > 1 && !idev->cnf.disable_ipv6) {
1444                 struct in6_addr addr;
1445
1446                 addr.s6_addr32[0] = htonl(0xfe800000);
1447                 addr.s6_addr32[1] = 0;
1448
1449                 if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
1450                     ipv6_addr_equal(&ifp->addr, &addr)) {
1451                         /* DAD failed for link-local based on MAC address */
1452                         idev->cnf.disable_ipv6 = 1;
1453
1454                         printk(KERN_INFO "%s: IPv6 being disabled!\n",
1455                                 ifp->idev->dev->name);
1456                 }
1457         }
1458
1459         addrconf_dad_stop(ifp, 1);
1460 }
1461
1462 /* Join to solicited addr multicast group. */
1463
1464 void addrconf_join_solict(struct net_device *dev, struct in6_addr *addr)
1465 {
1466         struct in6_addr maddr;
1467
1468         if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
1469                 return;
1470
1471         addrconf_addr_solict_mult(addr, &maddr);
1472         ipv6_dev_mc_inc(dev, &maddr);
1473 }
1474
1475 void addrconf_leave_solict(struct inet6_dev *idev, struct in6_addr *addr)
1476 {
1477         struct in6_addr maddr;
1478
1479         if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
1480                 return;
1481
1482         addrconf_addr_solict_mult(addr, &maddr);
1483         __ipv6_dev_mc_dec(idev, &maddr);
1484 }
1485
1486 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
1487 {
1488         struct in6_addr addr;
1489         ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
1490         if (ipv6_addr_any(&addr))
1491                 return;
1492         ipv6_dev_ac_inc(ifp->idev->dev, &addr);
1493 }
1494
1495 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
1496 {
1497         struct in6_addr addr;
1498         ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
1499         if (ipv6_addr_any(&addr))
1500                 return;
1501         __ipv6_dev_ac_dec(ifp->idev, &addr);
1502 }
1503
1504 static int addrconf_ifid_eui48(u8 *eui, struct net_device *dev)
1505 {
1506         if (dev->addr_len != ETH_ALEN)
1507                 return -1;
1508         memcpy(eui, dev->dev_addr, 3);
1509         memcpy(eui + 5, dev->dev_addr + 3, 3);
1510
1511         /*
1512          * The zSeries OSA network cards can be shared among various
1513          * OS instances, but the OSA cards have only one MAC address.
1514          * This leads to duplicate address conflicts in conjunction
1515          * with IPv6 if more than one instance uses the same card.
1516          *
1517          * The driver for these cards can deliver a unique 16-bit
1518          * identifier for each instance sharing the same card.  It is
1519          * placed instead of 0xFFFE in the interface identifier.  The
1520          * "u" bit of the interface identifier is not inverted in this
1521          * case.  Hence the resulting interface identifier has local
1522          * scope according to RFC2373.
1523          */
1524         if (dev->dev_id) {
1525                 eui[3] = (dev->dev_id >> 8) & 0xFF;
1526                 eui[4] = dev->dev_id & 0xFF;
1527         } else {
1528                 eui[3] = 0xFF;
1529                 eui[4] = 0xFE;
1530                 eui[0] ^= 2;
1531         }
1532         return 0;
1533 }
1534
1535 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
1536 {
1537         /* XXX: inherit EUI-64 from other interface -- yoshfuji */
1538         if (dev->addr_len != ARCNET_ALEN)
1539                 return -1;
1540         memset(eui, 0, 7);
1541         eui[7] = *(u8*)dev->dev_addr;
1542         return 0;
1543 }
1544
1545 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
1546 {
1547         if (dev->addr_len != INFINIBAND_ALEN)
1548                 return -1;
1549         memcpy(eui, dev->dev_addr + 12, 8);
1550         eui[0] |= 2;
1551         return 0;
1552 }
1553
1554 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
1555 {
1556         if (addr == 0)
1557                 return -1;
1558         eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
1559                   ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
1560                   ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
1561                   ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
1562                   ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
1563                   ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
1564         eui[1] = 0;
1565         eui[2] = 0x5E;
1566         eui[3] = 0xFE;
1567         memcpy(eui + 4, &addr, 4);
1568         return 0;
1569 }
1570
1571 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
1572 {
1573         if (dev->priv_flags & IFF_ISATAP)
1574                 return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
1575         return -1;
1576 }
1577
1578 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
1579 {
1580         switch (dev->type) {
1581         case ARPHRD_ETHER:
1582         case ARPHRD_FDDI:
1583         case ARPHRD_IEEE802_TR:
1584                 return addrconf_ifid_eui48(eui, dev);
1585         case ARPHRD_ARCNET:
1586                 return addrconf_ifid_arcnet(eui, dev);
1587         case ARPHRD_INFINIBAND:
1588                 return addrconf_ifid_infiniband(eui, dev);
1589         case ARPHRD_SIT:
1590                 return addrconf_ifid_sit(eui, dev);
1591         }
1592         return -1;
1593 }
1594
1595 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
1596 {
1597         int err = -1;
1598         struct inet6_ifaddr *ifp;
1599
1600         read_lock_bh(&idev->lock);
1601         list_for_each_entry(ifp, &idev->addr_list, if_list) {
1602                 if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
1603                         memcpy(eui, ifp->addr.s6_addr+8, 8);
1604                         err = 0;
1605                         break;
1606                 }
1607         }
1608         read_unlock_bh(&idev->lock);
1609         return err;
1610 }
1611
1612 #ifdef CONFIG_IPV6_PRIVACY
1613 /* (re)generation of randomized interface identifier (RFC 3041 3.2, 3.5) */
1614 static int __ipv6_regen_rndid(struct inet6_dev *idev)
1615 {
1616 regen:
1617         get_random_bytes(idev->rndid, sizeof(idev->rndid));
1618         idev->rndid[0] &= ~0x02;
1619
1620         /*
1621          * <draft-ietf-ipngwg-temp-addresses-v2-00.txt>:
1622          * check if generated address is not inappropriate
1623          *
1624          *  - Reserved subnet anycast (RFC 2526)
1625          *      11111101 11....11 1xxxxxxx
1626          *  - ISATAP (RFC4214) 6.1
1627          *      00-00-5E-FE-xx-xx-xx-xx
1628          *  - value 0
1629          *  - XXX: already assigned to an address on the device
1630          */
1631         if (idev->rndid[0] == 0xfd &&
1632             (idev->rndid[1]&idev->rndid[2]&idev->rndid[3]&idev->rndid[4]&idev->rndid[5]&idev->rndid[6]) == 0xff &&
1633             (idev->rndid[7]&0x80))
1634                 goto regen;
1635         if ((idev->rndid[0]|idev->rndid[1]) == 0) {
1636                 if (idev->rndid[2] == 0x5e && idev->rndid[3] == 0xfe)
1637                         goto regen;
1638                 if ((idev->rndid[2]|idev->rndid[3]|idev->rndid[4]|idev->rndid[5]|idev->rndid[6]|idev->rndid[7]) == 0x00)
1639                         goto regen;
1640         }
1641
1642         return 0;
1643 }
1644
1645 static void ipv6_regen_rndid(unsigned long data)
1646 {
1647         struct inet6_dev *idev = (struct inet6_dev *) data;
1648         unsigned long expires;
1649
1650         rcu_read_lock_bh();
1651         write_lock_bh(&idev->lock);
1652
1653         if (idev->dead)
1654                 goto out;
1655
1656         if (__ipv6_regen_rndid(idev) < 0)
1657                 goto out;
1658
1659         expires = jiffies +
1660                 idev->cnf.temp_prefered_lft * HZ -
1661                 idev->cnf.regen_max_retry * idev->cnf.dad_transmits * idev->nd_parms->retrans_time -
1662                 idev->cnf.max_desync_factor * HZ;
1663         if (time_before(expires, jiffies)) {
1664                 printk(KERN_WARNING
1665                         "ipv6_regen_rndid(): too short regeneration interval; timer disabled for %s.\n",
1666                         idev->dev->name);
1667                 goto out;
1668         }
1669
1670         if (!mod_timer(&idev->regen_timer, expires))
1671                 in6_dev_hold(idev);
1672
1673 out:
1674         write_unlock_bh(&idev->lock);
1675         rcu_read_unlock_bh();
1676         in6_dev_put(idev);
1677 }
1678
1679 static int __ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr) {
1680         int ret = 0;
1681
1682         if (tmpaddr && memcmp(idev->rndid, &tmpaddr->s6_addr[8], 8) == 0)
1683                 ret = __ipv6_regen_rndid(idev);
1684         return ret;
1685 }
1686 #endif
1687
1688 /*
1689  *      Add prefix route.
1690  */
1691
1692 static void
1693 addrconf_prefix_route(struct in6_addr *pfx, int plen, struct net_device *dev,
1694                       unsigned long expires, u32 flags)
1695 {
1696         struct fib6_config cfg = {
1697                 .fc_table = RT6_TABLE_PREFIX,
1698                 .fc_metric = IP6_RT_PRIO_ADDRCONF,
1699                 .fc_ifindex = dev->ifindex,
1700                 .fc_expires = expires,
1701                 .fc_dst_len = plen,
1702                 .fc_flags = RTF_UP | flags,
1703                 .fc_nlinfo.nl_net = dev_net(dev),
1704                 .fc_protocol = RTPROT_KERNEL,
1705         };
1706
1707         ipv6_addr_copy(&cfg.fc_dst, pfx);
1708
1709         /* Prevent useless cloning on PtP SIT.
1710            This thing is done here expecting that the whole
1711            class of non-broadcast devices need not cloning.
1712          */
1713 #if defined(CONFIG_IPV6_SIT) || defined(CONFIG_IPV6_SIT_MODULE)
1714         if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
1715                 cfg.fc_flags |= RTF_NONEXTHOP;
1716 #endif
1717
1718         ip6_route_add(&cfg);
1719 }
1720
1721 /* Create "default" multicast route to the interface */
1722
1723 static void addrconf_add_mroute(struct net_device *dev)
1724 {
1725         struct fib6_config cfg = {
1726                 .fc_table = RT6_TABLE_LOCAL,
1727                 .fc_metric = IP6_RT_PRIO_ADDRCONF,
1728                 .fc_ifindex = dev->ifindex,
1729                 .fc_dst_len = 8,
1730                 .fc_flags = RTF_UP,
1731                 .fc_nlinfo.nl_net = dev_net(dev),
1732         };
1733
1734         ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
1735
1736         ip6_route_add(&cfg);
1737 }
1738
1739 #if defined(CONFIG_IPV6_SIT) || defined(CONFIG_IPV6_SIT_MODULE)
1740 static void sit_route_add(struct net_device *dev)
1741 {
1742         struct fib6_config cfg = {
1743                 .fc_table = RT6_TABLE_MAIN,
1744                 .fc_metric = IP6_RT_PRIO_ADDRCONF,
1745                 .fc_ifindex = dev->ifindex,
1746                 .fc_dst_len = 96,
1747                 .fc_flags = RTF_UP | RTF_NONEXTHOP,
1748                 .fc_nlinfo.nl_net = dev_net(dev),
1749         };
1750
1751         /* prefix length - 96 bits "::d.d.d.d" */
1752         ip6_route_add(&cfg);
1753 }
1754 #endif
1755
1756 static void addrconf_add_lroute(struct net_device *dev)
1757 {
1758         struct in6_addr addr;
1759
1760         ipv6_addr_set(&addr,  htonl(0xFE800000), 0, 0, 0);
1761         addrconf_prefix_route(&addr, 64, dev, 0, 0);
1762 }
1763
1764 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
1765 {
1766         struct inet6_dev *idev;
1767
1768         ASSERT_RTNL();
1769
1770         idev = ipv6_find_idev(dev);
1771         if (!idev)
1772                 return ERR_PTR(-ENOBUFS);
1773
1774         if (idev->cnf.disable_ipv6)
1775                 return ERR_PTR(-EACCES);
1776
1777         /* Add default multicast route */
1778         addrconf_add_mroute(dev);
1779
1780         /* Add link local route */
1781         addrconf_add_lroute(dev);
1782         return idev;
1783 }
1784
1785 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len)
1786 {
1787         struct prefix_info *pinfo;
1788         __u32 valid_lft;
1789         __u32 prefered_lft;
1790         int addr_type;
1791         struct inet6_dev *in6_dev;
1792         struct net *net = dev_net(dev);
1793
1794         pinfo = (struct prefix_info *) opt;
1795
1796         if (len < sizeof(struct prefix_info)) {
1797                 ADBG(("addrconf: prefix option too short\n"));
1798                 return;
1799         }
1800
1801         /*
1802          *      Validation checks ([ADDRCONF], page 19)
1803          */
1804
1805         addr_type = ipv6_addr_type(&pinfo->prefix);
1806
1807         if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
1808                 return;
1809
1810         valid_lft = ntohl(pinfo->valid);
1811         prefered_lft = ntohl(pinfo->prefered);
1812
1813         if (prefered_lft > valid_lft) {
1814                 if (net_ratelimit())
1815                         printk(KERN_WARNING "addrconf: prefix option has invalid lifetime\n");
1816                 return;
1817         }
1818
1819         in6_dev = in6_dev_get(dev);
1820
1821         if (in6_dev == NULL) {
1822                 if (net_ratelimit())
1823                         printk(KERN_DEBUG "addrconf: device %s not configured\n", dev->name);
1824                 return;
1825         }
1826
1827         /*
1828          *      Two things going on here:
1829          *      1) Add routes for on-link prefixes
1830          *      2) Configure prefixes with the auto flag set
1831          */
1832
1833         if (pinfo->onlink) {
1834                 struct rt6_info *rt;
1835                 unsigned long rt_expires;
1836
1837                 /* Avoid arithmetic overflow. Really, we could
1838                  * save rt_expires in seconds, likely valid_lft,
1839                  * but it would require division in fib gc, that it
1840                  * not good.
1841                  */
1842                 if (HZ > USER_HZ)
1843                         rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
1844                 else
1845                         rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
1846
1847                 if (addrconf_finite_timeout(rt_expires))
1848                         rt_expires *= HZ;
1849
1850                 rt = rt6_lookup(net, &pinfo->prefix, NULL,
1851                                 dev->ifindex, 1);
1852
1853                 if (rt && addrconf_is_prefix_route(rt)) {
1854                         /* Autoconf prefix route */
1855                         if (valid_lft == 0) {
1856                                 ip6_del_rt(rt);
1857                                 rt = NULL;
1858                         } else if (addrconf_finite_timeout(rt_expires)) {
1859                                 /* not infinity */
1860                                 rt->rt6i_expires = jiffies + rt_expires;
1861                                 rt->rt6i_flags |= RTF_EXPIRES;
1862                         } else {
1863                                 rt->rt6i_flags &= ~RTF_EXPIRES;
1864                                 rt->rt6i_expires = 0;
1865                         }
1866                 } else if (valid_lft) {
1867                         clock_t expires = 0;
1868                         int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
1869                         if (addrconf_finite_timeout(rt_expires)) {
1870                                 /* not infinity */
1871                                 flags |= RTF_EXPIRES;
1872                                 expires = jiffies_to_clock_t(rt_expires);
1873                         }
1874                         addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
1875                                               dev, expires, flags);
1876                 }
1877                 if (rt)
1878                         dst_release(&rt->dst);
1879         }
1880
1881         /* Try to figure out our local address for this prefix */
1882
1883         if (pinfo->autoconf && in6_dev->cnf.autoconf) {
1884                 struct inet6_ifaddr * ifp;
1885                 struct in6_addr addr;
1886                 int create = 0, update_lft = 0;
1887
1888                 if (pinfo->prefix_len == 64) {
1889                         memcpy(&addr, &pinfo->prefix, 8);
1890                         if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
1891                             ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
1892                                 in6_dev_put(in6_dev);
1893                                 return;
1894                         }
1895                         goto ok;
1896                 }
1897                 if (net_ratelimit())
1898                         printk(KERN_DEBUG "IPv6 addrconf: prefix with wrong length %d\n",
1899                                pinfo->prefix_len);
1900                 in6_dev_put(in6_dev);
1901                 return;
1902
1903 ok:
1904
1905                 ifp = ipv6_get_ifaddr(net, &addr, dev, 1);
1906
1907                 if (ifp == NULL && valid_lft) {
1908                         int max_addresses = in6_dev->cnf.max_addresses;
1909                         u32 addr_flags = 0;
1910
1911 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1912                         if (in6_dev->cnf.optimistic_dad &&
1913                             !net->ipv6.devconf_all->forwarding)
1914                                 addr_flags = IFA_F_OPTIMISTIC;
1915 #endif
1916
1917                         /* Do not allow to create too much of autoconfigured
1918                          * addresses; this would be too easy way to crash kernel.
1919                          */
1920                         if (!max_addresses ||
1921                             ipv6_count_addresses(in6_dev) < max_addresses)
1922                                 ifp = ipv6_add_addr(in6_dev, &addr, pinfo->prefix_len,
1923                                                     addr_type&IPV6_ADDR_SCOPE_MASK,
1924                                                     addr_flags);
1925
1926                         if (!ifp || IS_ERR(ifp)) {
1927                                 in6_dev_put(in6_dev);
1928                                 return;
1929                         }
1930
1931                         update_lft = create = 1;
1932                         ifp->cstamp = jiffies;
1933                         addrconf_dad_start(ifp, RTF_ADDRCONF|RTF_PREFIX_RT);
1934                 }
1935
1936                 if (ifp) {
1937                         int flags;
1938                         unsigned long now;
1939 #ifdef CONFIG_IPV6_PRIVACY
1940                         struct inet6_ifaddr *ift;
1941 #endif
1942                         u32 stored_lft;
1943
1944                         /* update lifetime (RFC2462 5.5.3 e) */
1945                         spin_lock(&ifp->lock);
1946                         now = jiffies;
1947                         if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
1948                                 stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
1949                         else
1950                                 stored_lft = 0;
1951                         if (!update_lft && stored_lft) {
1952                                 if (valid_lft > MIN_VALID_LIFETIME ||
1953                                     valid_lft > stored_lft)
1954                                         update_lft = 1;
1955                                 else if (stored_lft <= MIN_VALID_LIFETIME) {
1956                                         /* valid_lft <= stored_lft is always true */
1957                                         /*
1958                                          * RFC 4862 Section 5.5.3e:
1959                                          * "Note that the preferred lifetime of
1960                                          *  the corresponding address is always
1961                                          *  reset to the Preferred Lifetime in
1962                                          *  the received Prefix Information
1963                                          *  option, regardless of whether the
1964                                          *  valid lifetime is also reset or
1965                                          *  ignored."
1966                                          *
1967                                          *  So if the preferred lifetime in
1968                                          *  this advertisement is different
1969                                          *  than what we have stored, but the
1970                                          *  valid lifetime is invalid, just
1971                                          *  reset prefered_lft.
1972                                          *
1973                                          *  We must set the valid lifetime
1974                                          *  to the stored lifetime since we'll
1975                                          *  be updating the timestamp below,
1976                                          *  else we'll set it back to the
1977                                          *  minumum.
1978                                          */
1979                                         if (prefered_lft != ifp->prefered_lft) {
1980                                                 valid_lft = stored_lft;
1981                                                 update_lft = 1;
1982                                         }
1983                                 } else {
1984                                         valid_lft = MIN_VALID_LIFETIME;
1985                                         if (valid_lft < prefered_lft)
1986                                                 prefered_lft = valid_lft;
1987                                         update_lft = 1;
1988                                 }
1989                         }
1990
1991                         if (update_lft) {
1992                                 ifp->valid_lft = valid_lft;
1993                                 ifp->prefered_lft = prefered_lft;
1994                                 ifp->tstamp = now;
1995                                 flags = ifp->flags;
1996                                 ifp->flags &= ~IFA_F_DEPRECATED;
1997                                 spin_unlock(&ifp->lock);
1998
1999                                 if (!(flags&IFA_F_TENTATIVE))
2000                                         ipv6_ifa_notify(0, ifp);
2001                         } else
2002                                 spin_unlock(&ifp->lock);
2003
2004 #ifdef CONFIG_IPV6_PRIVACY
2005                         read_lock_bh(&in6_dev->lock);
2006                         /* update all temporary addresses in the list */
2007                         list_for_each_entry(ift, &in6_dev->tempaddr_list, tmp_list) {
2008                                 /*
2009                                  * When adjusting the lifetimes of an existing
2010                                  * temporary address, only lower the lifetimes.
2011                                  * Implementations must not increase the
2012                                  * lifetimes of an existing temporary address
2013                                  * when processing a Prefix Information Option.
2014                                  */
2015                                 if (ifp != ift->ifpub)
2016                                         continue;
2017
2018                                 spin_lock(&ift->lock);
2019                                 flags = ift->flags;
2020                                 if (ift->valid_lft > valid_lft &&
2021                                     ift->valid_lft - valid_lft > (jiffies - ift->tstamp) / HZ)
2022                                         ift->valid_lft = valid_lft + (jiffies - ift->tstamp) / HZ;
2023                                 if (ift->prefered_lft > prefered_lft &&
2024                                     ift->prefered_lft - prefered_lft > (jiffies - ift->tstamp) / HZ)
2025                                         ift->prefered_lft = prefered_lft + (jiffies - ift->tstamp) / HZ;
2026                                 spin_unlock(&ift->lock);
2027                                 if (!(flags&IFA_F_TENTATIVE))
2028                                         ipv6_ifa_notify(0, ift);
2029                         }
2030
2031                         if ((create || list_empty(&in6_dev->tempaddr_list)) && in6_dev->cnf.use_tempaddr > 0) {
2032                                 /*
2033                                  * When a new public address is created as described in [ADDRCONF],
2034                                  * also create a new temporary address. Also create a temporary
2035                                  * address if it's enabled but no temporary address currently exists.
2036                                  */
2037                                 read_unlock_bh(&in6_dev->lock);
2038                                 ipv6_create_tempaddr(ifp, NULL);
2039                         } else {
2040                                 read_unlock_bh(&in6_dev->lock);
2041                         }
2042 #endif
2043                         in6_ifa_put(ifp);
2044                         addrconf_verify(0);
2045                 }
2046         }
2047         inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2048         in6_dev_put(in6_dev);
2049 }
2050
2051 /*
2052  *      Set destination address.
2053  *      Special case for SIT interfaces where we create a new "virtual"
2054  *      device.
2055  */
2056 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2057 {
2058         struct in6_ifreq ireq;
2059         struct net_device *dev;
2060         int err = -EINVAL;
2061
2062         rtnl_lock();
2063
2064         err = -EFAULT;
2065         if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2066                 goto err_exit;
2067
2068         dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2069
2070         err = -ENODEV;
2071         if (dev == NULL)
2072                 goto err_exit;
2073
2074 #if defined(CONFIG_IPV6_SIT) || defined(CONFIG_IPV6_SIT_MODULE)
2075         if (dev->type == ARPHRD_SIT) {
2076                 const struct net_device_ops *ops = dev->netdev_ops;
2077                 struct ifreq ifr;
2078                 struct ip_tunnel_parm p;
2079
2080                 err = -EADDRNOTAVAIL;
2081                 if (!(ipv6_addr_type(&ireq.ifr6_addr) & IPV6_ADDR_COMPATv4))
2082                         goto err_exit;
2083
2084                 memset(&p, 0, sizeof(p));
2085                 p.iph.daddr = ireq.ifr6_addr.s6_addr32[3];
2086                 p.iph.saddr = 0;
2087                 p.iph.version = 4;
2088                 p.iph.ihl = 5;
2089                 p.iph.protocol = IPPROTO_IPV6;
2090                 p.iph.ttl = 64;
2091                 ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
2092
2093                 if (ops->ndo_do_ioctl) {
2094                         mm_segment_t oldfs = get_fs();
2095
2096                         set_fs(KERNEL_DS);
2097                         err = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
2098                         set_fs(oldfs);
2099                 } else
2100                         err = -EOPNOTSUPP;
2101
2102                 if (err == 0) {
2103                         err = -ENOBUFS;
2104                         dev = __dev_get_by_name(net, p.name);
2105                         if (!dev)
2106                                 goto err_exit;
2107                         err = dev_open(dev);
2108                 }
2109         }
2110 #endif
2111
2112 err_exit:
2113         rtnl_unlock();
2114         return err;
2115 }
2116
2117 /*
2118  *      Manual configuration of address on an interface
2119  */
2120 static int inet6_addr_add(struct net *net, int ifindex, struct in6_addr *pfx,
2121                           unsigned int plen, __u8 ifa_flags, __u32 prefered_lft,
2122                           __u32 valid_lft)
2123 {
2124         struct inet6_ifaddr *ifp;
2125         struct inet6_dev *idev;
2126         struct net_device *dev;
2127         int scope;
2128         u32 flags;
2129         clock_t expires;
2130         unsigned long timeout;
2131
2132         ASSERT_RTNL();
2133
2134         if (plen > 128)
2135                 return -EINVAL;
2136
2137         /* check the lifetime */
2138         if (!valid_lft || prefered_lft > valid_lft)
2139                 return -EINVAL;
2140
2141         dev = __dev_get_by_index(net, ifindex);
2142         if (!dev)
2143                 return -ENODEV;
2144
2145         idev = addrconf_add_dev(dev);
2146         if (IS_ERR(idev))
2147                 return PTR_ERR(idev);
2148
2149         scope = ipv6_addr_scope(pfx);
2150
2151         timeout = addrconf_timeout_fixup(valid_lft, HZ);
2152         if (addrconf_finite_timeout(timeout)) {
2153                 expires = jiffies_to_clock_t(timeout * HZ);
2154                 valid_lft = timeout;
2155                 flags = RTF_EXPIRES;
2156         } else {
2157                 expires = 0;
2158                 flags = 0;
2159                 ifa_flags |= IFA_F_PERMANENT;
2160         }
2161
2162         timeout = addrconf_timeout_fixup(prefered_lft, HZ);
2163         if (addrconf_finite_timeout(timeout)) {
2164                 if (timeout == 0)
2165                         ifa_flags |= IFA_F_DEPRECATED;
2166                 prefered_lft = timeout;
2167         }
2168
2169         ifp = ipv6_add_addr(idev, pfx, plen, scope, ifa_flags);
2170
2171         if (!IS_ERR(ifp)) {
2172                 spin_lock_bh(&ifp->lock);
2173                 ifp->valid_lft = valid_lft;
2174                 ifp->prefered_lft = prefered_lft;
2175                 ifp->tstamp = jiffies;
2176                 spin_unlock_bh(&ifp->lock);
2177
2178                 addrconf_prefix_route(&ifp->addr, ifp->prefix_len, dev,
2179                                       expires, flags);
2180                 /*
2181                  * Note that section 3.1 of RFC 4429 indicates
2182                  * that the Optimistic flag should not be set for
2183                  * manually configured addresses
2184                  */
2185                 addrconf_dad_start(ifp, 0);
2186                 in6_ifa_put(ifp);
2187                 addrconf_verify(0);
2188                 return 0;
2189         }
2190
2191         return PTR_ERR(ifp);
2192 }
2193
2194 static int inet6_addr_del(struct net *net, int ifindex, struct in6_addr *pfx,
2195                           unsigned int plen)
2196 {
2197         struct inet6_ifaddr *ifp;
2198         struct inet6_dev *idev;
2199         struct net_device *dev;
2200
2201         if (plen > 128)
2202                 return -EINVAL;
2203
2204         dev = __dev_get_by_index(net, ifindex);
2205         if (!dev)
2206                 return -ENODEV;
2207
2208         if ((idev = __in6_dev_get(dev)) == NULL)
2209                 return -ENXIO;
2210
2211         read_lock_bh(&idev->lock);
2212         list_for_each_entry(ifp, &idev->addr_list, if_list) {
2213                 if (ifp->prefix_len == plen &&
2214                     ipv6_addr_equal(pfx, &ifp->addr)) {
2215                         in6_ifa_hold(ifp);
2216                         read_unlock_bh(&idev->lock);
2217
2218                         ipv6_del_addr(ifp);
2219
2220                         /* If the last address is deleted administratively,
2221                            disable IPv6 on this interface.
2222                          */
2223                         if (list_empty(&idev->addr_list))
2224                                 addrconf_ifdown(idev->dev, 1);
2225                         return 0;
2226                 }
2227         }
2228         read_unlock_bh(&idev->lock);
2229         return -EADDRNOTAVAIL;
2230 }
2231
2232
2233 int addrconf_add_ifaddr(struct net *net, void __user *arg)
2234 {
2235         struct in6_ifreq ireq;
2236         int err;
2237
2238         if (!capable(CAP_NET_ADMIN))
2239                 return -EPERM;
2240
2241         if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2242                 return -EFAULT;
2243
2244         rtnl_lock();
2245         err = inet6_addr_add(net, ireq.ifr6_ifindex, &ireq.ifr6_addr,
2246                              ireq.ifr6_prefixlen, IFA_F_PERMANENT,
2247                              INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
2248         rtnl_unlock();
2249         return err;
2250 }
2251
2252 int addrconf_del_ifaddr(struct net *net, void __user *arg)
2253 {
2254         struct in6_ifreq ireq;
2255         int err;
2256
2257         if (!capable(CAP_NET_ADMIN))
2258                 return -EPERM;
2259
2260         if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2261                 return -EFAULT;
2262
2263         rtnl_lock();
2264         err = inet6_addr_del(net, ireq.ifr6_ifindex, &ireq.ifr6_addr,
2265                              ireq.ifr6_prefixlen);
2266         rtnl_unlock();
2267         return err;
2268 }
2269
2270 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
2271                      int plen, int scope)
2272 {
2273         struct inet6_ifaddr *ifp;
2274
2275         ifp = ipv6_add_addr(idev, addr, plen, scope, IFA_F_PERMANENT);
2276         if (!IS_ERR(ifp)) {
2277                 spin_lock_bh(&ifp->lock);
2278                 ifp->flags &= ~IFA_F_TENTATIVE;
2279                 spin_unlock_bh(&ifp->lock);
2280                 ipv6_ifa_notify(RTM_NEWADDR, ifp);
2281                 in6_ifa_put(ifp);
2282         }
2283 }
2284
2285 #if defined(CONFIG_IPV6_SIT) || defined(CONFIG_IPV6_SIT_MODULE)
2286 static void sit_add_v4_addrs(struct inet6_dev *idev)
2287 {
2288         struct in6_addr addr;
2289         struct net_device *dev;
2290         struct net *net = dev_net(idev->dev);
2291         int scope;
2292
2293         ASSERT_RTNL();
2294
2295         memset(&addr, 0, sizeof(struct in6_addr));
2296         memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
2297
2298         if (idev->dev->flags&IFF_POINTOPOINT) {
2299                 addr.s6_addr32[0] = htonl(0xfe800000);
2300                 scope = IFA_LINK;
2301         } else {
2302                 scope = IPV6_ADDR_COMPATv4;
2303         }
2304
2305         if (addr.s6_addr32[3]) {
2306                 add_addr(idev, &addr, 128, scope);
2307                 return;
2308         }
2309
2310         for_each_netdev(net, dev) {
2311                 struct in_device * in_dev = __in_dev_get_rtnl(dev);
2312                 if (in_dev && (dev->flags & IFF_UP)) {
2313                         struct in_ifaddr * ifa;
2314
2315                         int flag = scope;
2316
2317                         for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
2318                                 int plen;
2319
2320                                 addr.s6_addr32[3] = ifa->ifa_local;
2321
2322                                 if (ifa->ifa_scope == RT_SCOPE_LINK)
2323                                         continue;
2324                                 if (ifa->ifa_scope >= RT_SCOPE_HOST) {
2325                                         if (idev->dev->flags&IFF_POINTOPOINT)
2326                                                 continue;
2327                                         flag |= IFA_HOST;
2328                                 }
2329                                 if (idev->dev->flags&IFF_POINTOPOINT)
2330                                         plen = 64;
2331                                 else
2332                                         plen = 96;
2333
2334                                 add_addr(idev, &addr, plen, flag);
2335                         }
2336                 }
2337         }
2338 }
2339 #endif
2340
2341 static void init_loopback(struct net_device *dev)
2342 {
2343         struct inet6_dev  *idev;
2344
2345         /* ::1 */
2346
2347         ASSERT_RTNL();
2348
2349         if ((idev = ipv6_find_idev(dev)) == NULL) {
2350                 printk(KERN_DEBUG "init loopback: add_dev failed\n");
2351                 return;
2352         }
2353
2354         add_addr(idev, &in6addr_loopback, 128, IFA_HOST);
2355 }
2356
2357 static void addrconf_add_linklocal(struct inet6_dev *idev, struct in6_addr *addr)
2358 {
2359         struct inet6_ifaddr * ifp;
2360         u32 addr_flags = IFA_F_PERMANENT;
2361
2362 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2363         if (idev->cnf.optimistic_dad &&
2364             !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
2365                 addr_flags |= IFA_F_OPTIMISTIC;
2366 #endif
2367
2368
2369         ifp = ipv6_add_addr(idev, addr, 64, IFA_LINK, addr_flags);
2370         if (!IS_ERR(ifp)) {
2371                 addrconf_prefix_route(&ifp->addr, ifp->prefix_len, idev->dev, 0, 0);
2372                 addrconf_dad_start(ifp, 0);
2373                 in6_ifa_put(ifp);
2374         }
2375 }
2376
2377 static void addrconf_dev_config(struct net_device *dev)
2378 {
2379         struct in6_addr addr;
2380         struct inet6_dev    * idev;
2381
2382         ASSERT_RTNL();
2383
2384         if ((dev->type != ARPHRD_ETHER) &&
2385             (dev->type != ARPHRD_FDDI) &&
2386             (dev->type != ARPHRD_IEEE802_TR) &&
2387             (dev->type != ARPHRD_ARCNET) &&
2388             (dev->type != ARPHRD_INFINIBAND)) {
2389                 /* Alas, we support only Ethernet autoconfiguration. */
2390                 return;
2391         }
2392
2393         idev = addrconf_add_dev(dev);
2394         if (IS_ERR(idev))
2395                 return;
2396
2397         memset(&addr, 0, sizeof(struct in6_addr));
2398         addr.s6_addr32[0] = htonl(0xFE800000);
2399
2400         if (ipv6_generate_eui64(addr.s6_addr + 8, dev) == 0)
2401                 addrconf_add_linklocal(idev, &addr);
2402 }
2403
2404 #if defined(CONFIG_IPV6_SIT) || defined(CONFIG_IPV6_SIT_MODULE)
2405 static void addrconf_sit_config(struct net_device *dev)
2406 {
2407         struct inet6_dev *idev;
2408
2409         ASSERT_RTNL();
2410
2411         /*
2412          * Configure the tunnel with one of our IPv4
2413          * addresses... we should configure all of
2414          * our v4 addrs in the tunnel
2415          */
2416
2417         if ((idev = ipv6_find_idev(dev)) == NULL) {
2418                 printk(KERN_DEBUG "init sit: add_dev failed\n");
2419                 return;
2420         }
2421
2422         if (dev->priv_flags & IFF_ISATAP) {
2423                 struct in6_addr addr;
2424
2425                 ipv6_addr_set(&addr,  htonl(0xFE800000), 0, 0, 0);
2426                 addrconf_prefix_route(&addr, 64, dev, 0, 0);
2427                 if (!ipv6_generate_eui64(addr.s6_addr + 8, dev))
2428                         addrconf_add_linklocal(idev, &addr);
2429                 return;
2430         }
2431
2432         sit_add_v4_addrs(idev);
2433
2434         if (dev->flags&IFF_POINTOPOINT) {
2435                 addrconf_add_mroute(dev);
2436                 addrconf_add_lroute(dev);
2437         } else
2438                 sit_route_add(dev);
2439 }
2440 #endif
2441
2442 static inline int
2443 ipv6_inherit_linklocal(struct inet6_dev *idev, struct net_device *link_dev)
2444 {
2445         struct in6_addr lladdr;
2446
2447         if (!ipv6_get_lladdr(link_dev, &lladdr, IFA_F_TENTATIVE)) {
2448                 addrconf_add_linklocal(idev, &lladdr);
2449                 return 0;
2450         }
2451         return -1;
2452 }
2453
2454 static void ip6_tnl_add_linklocal(struct inet6_dev *idev)
2455 {
2456         struct net_device *link_dev;
2457         struct net *net = dev_net(idev->dev);
2458
2459         /* first try to inherit the link-local address from the link device */
2460         if (idev->dev->iflink &&
2461             (link_dev = __dev_get_by_index(net, idev->dev->iflink))) {
2462                 if (!ipv6_inherit_linklocal(idev, link_dev))
2463                         return;
2464         }
2465         /* then try to inherit it from any device */
2466         for_each_netdev(net, link_dev) {
2467                 if (!ipv6_inherit_linklocal(idev, link_dev))
2468                         return;
2469         }
2470         printk(KERN_DEBUG "init ip6-ip6: add_linklocal failed\n");
2471 }
2472
2473 /*
2474  * Autoconfigure tunnel with a link-local address so routing protocols,
2475  * DHCPv6, MLD etc. can be run over the virtual link
2476  */
2477
2478 static void addrconf_ip6_tnl_config(struct net_device *dev)
2479 {
2480         struct inet6_dev *idev;
2481
2482         ASSERT_RTNL();
2483
2484         idev = addrconf_add_dev(dev);
2485         if (IS_ERR(idev)) {
2486                 printk(KERN_DEBUG "init ip6-ip6: add_dev failed\n");
2487                 return;
2488         }
2489         ip6_tnl_add_linklocal(idev);
2490 }
2491
2492 static int addrconf_notify(struct notifier_block *this, unsigned long event,
2493                            void * data)
2494 {
2495         struct net_device *dev = (struct net_device *) data;
2496         struct inet6_dev *idev = __in6_dev_get(dev);
2497         int run_pending = 0;
2498         int err;
2499
2500         switch (event) {
2501         case NETDEV_REGISTER:
2502                 if (!idev && dev->mtu >= IPV6_MIN_MTU) {
2503                         idev = ipv6_add_dev(dev);
2504                         if (!idev)
2505                                 return notifier_from_errno(-ENOMEM);
2506                 }
2507                 break;
2508
2509         case NETDEV_UP:
2510         case NETDEV_CHANGE:
2511                 if (dev->flags & IFF_SLAVE)
2512                         break;
2513
2514                 if (event == NETDEV_UP) {
2515                         if (!addrconf_qdisc_ok(dev)) {
2516                                 /* device is not ready yet. */
2517                                 printk(KERN_INFO
2518                                         "ADDRCONF(NETDEV_UP): %s: "
2519                                         "link is not ready\n",
2520                                         dev->name);
2521                                 break;
2522                         }
2523
2524                         if (!idev && dev->mtu >= IPV6_MIN_MTU)
2525                                 idev = ipv6_add_dev(dev);
2526
2527                         if (idev) {
2528                                 idev->if_flags |= IF_READY;
2529                                 run_pending = 1;
2530                         }
2531                 } else {
2532                         if (!addrconf_qdisc_ok(dev)) {
2533                                 /* device is still not ready. */
2534                                 break;
2535                         }
2536
2537                         if (idev) {
2538                                 if (idev->if_flags & IF_READY)
2539                                         /* device is already configured. */
2540                                         break;
2541                                 idev->if_flags |= IF_READY;
2542                         }
2543
2544                         printk(KERN_INFO
2545                                         "ADDRCONF(NETDEV_CHANGE): %s: "
2546                                         "link becomes ready\n",
2547                                         dev->name);
2548
2549                         run_pending = 1;
2550                 }
2551
2552                 switch (dev->type) {
2553 #if defined(CONFIG_IPV6_SIT) || defined(CONFIG_IPV6_SIT_MODULE)
2554                 case ARPHRD_SIT:
2555                         addrconf_sit_config(dev);
2556                         break;
2557 #endif
2558                 case ARPHRD_TUNNEL6:
2559                         addrconf_ip6_tnl_config(dev);
2560                         break;
2561                 case ARPHRD_LOOPBACK:
2562                         init_loopback(dev);
2563                         break;
2564
2565                 default:
2566                         addrconf_dev_config(dev);
2567                         break;
2568                 }
2569
2570                 if (idev) {
2571                         if (run_pending)
2572                                 addrconf_dad_run(idev);
2573
2574                         /*
2575                          * If the MTU changed during the interface down,
2576                          * when the interface up, the changed MTU must be
2577                          * reflected in the idev as well as routers.
2578                          */
2579                         if (idev->cnf.mtu6 != dev->mtu &&
2580                             dev->mtu >= IPV6_MIN_MTU) {
2581                                 rt6_mtu_change(dev, dev->mtu);
2582                                 idev->cnf.mtu6 = dev->mtu;
2583                         }
2584                         idev->tstamp = jiffies;
2585                         inet6_ifinfo_notify(RTM_NEWLINK, idev);
2586
2587                         /*
2588                          * If the changed mtu during down is lower than
2589                          * IPV6_MIN_MTU stop IPv6 on this interface.
2590                          */
2591                         if (dev->mtu < IPV6_MIN_MTU)
2592                                 addrconf_ifdown(dev, 1);
2593                 }
2594                 break;
2595
2596         case NETDEV_CHANGEMTU:
2597                 if (idev && dev->mtu >= IPV6_MIN_MTU) {
2598                         rt6_mtu_change(dev, dev->mtu);
2599                         idev->cnf.mtu6 = dev->mtu;
2600                         break;
2601                 }
2602
2603                 if (!idev && dev->mtu >= IPV6_MIN_MTU) {
2604                         idev = ipv6_add_dev(dev);
2605                         if (idev)
2606                                 break;
2607                 }
2608
2609                 /*
2610                  * MTU falled under IPV6_MIN_MTU.
2611                  * Stop IPv6 on this interface.
2612                  */
2613
2614         case NETDEV_DOWN:
2615         case NETDEV_UNREGISTER:
2616                 /*
2617                  *      Remove all addresses from this interface.
2618                  */
2619                 addrconf_ifdown(dev, event != NETDEV_DOWN);
2620                 break;
2621
2622         case NETDEV_CHANGENAME:
2623                 if (idev) {
2624                         snmp6_unregister_dev(idev);
2625                         addrconf_sysctl_unregister(idev);
2626                         addrconf_sysctl_register(idev);
2627                         err = snmp6_register_dev(idev);
2628                         if (err)
2629                                 return notifier_from_errno(err);
2630                 }
2631                 break;
2632
2633         case NETDEV_PRE_TYPE_CHANGE:
2634         case NETDEV_POST_TYPE_CHANGE:
2635                 addrconf_type_change(dev, event);
2636                 break;
2637         }
2638
2639         return NOTIFY_OK;
2640 }
2641
2642 /*
2643  *      addrconf module should be notified of a device going up
2644  */
2645 static struct notifier_block ipv6_dev_notf = {
2646         .notifier_call = addrconf_notify,
2647 };
2648
2649 static void addrconf_type_change(struct net_device *dev, unsigned long event)
2650 {
2651         struct inet6_dev *idev;
2652         ASSERT_RTNL();
2653
2654         idev = __in6_dev_get(dev);
2655
2656         if (event == NETDEV_POST_TYPE_CHANGE)
2657                 ipv6_mc_remap(idev);
2658         else if (event == NETDEV_PRE_TYPE_CHANGE)
2659                 ipv6_mc_unmap(idev);
2660 }
2661
2662 static int addrconf_ifdown(struct net_device *dev, int how)
2663 {
2664         struct net *net = dev_net(dev);
2665         struct inet6_dev *idev;
2666         struct inet6_ifaddr *ifa;
2667         LIST_HEAD(keep_list);
2668         int state;
2669
2670         ASSERT_RTNL();
2671
2672         rt6_ifdown(net, dev);
2673         neigh_ifdown(&nd_tbl, dev);
2674
2675         idev = __in6_dev_get(dev);
2676         if (idev == NULL)
2677                 return -ENODEV;
2678
2679         /*
2680          * Step 1: remove reference to ipv6 device from parent device.
2681          *         Do not dev_put!
2682          */
2683         if (how) {
2684                 idev->dead = 1;
2685
2686                 /* protected by rtnl_lock */
2687                 rcu_assign_pointer(dev->ip6_ptr, NULL);
2688
2689                 /* Step 1.5: remove snmp6 entry */
2690                 snmp6_unregister_dev(idev);
2691
2692         }
2693
2694         write_lock_bh(&idev->lock);
2695
2696         /* Step 2: clear flags for stateless addrconf */
2697         if (!how)
2698                 idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
2699
2700 #ifdef CONFIG_IPV6_PRIVACY
2701         if (how && del_timer(&idev->regen_timer))
2702                 in6_dev_put(idev);
2703
2704         /* Step 3: clear tempaddr list */
2705         while (!list_empty(&idev->tempaddr_list)) {
2706                 ifa = list_first_entry(&idev->tempaddr_list,
2707                                        struct inet6_ifaddr, tmp_list);
2708                 list_del(&ifa->tmp_list);
2709                 write_unlock_bh(&idev->lock);
2710                 spin_lock_bh(&ifa->lock);
2711
2712                 if (ifa->ifpub) {
2713                         in6_ifa_put(ifa->ifpub);
2714                         ifa->ifpub = NULL;
2715                 }
2716                 spin_unlock_bh(&ifa->lock);
2717                 in6_ifa_put(ifa);
2718                 write_lock_bh(&idev->lock);
2719         }
2720 #endif
2721
2722         while (!list_empty(&idev->addr_list)) {
2723                 ifa = list_first_entry(&idev->addr_list,
2724                                        struct inet6_ifaddr, if_list);
2725                 addrconf_del_timer(ifa);
2726
2727                 /* If just doing link down, and address is permanent
2728                    and not link-local, then retain it. */
2729                 if (!how &&
2730                     (ifa->flags&IFA_F_PERMANENT) &&
2731                     !(ipv6_addr_type(&ifa->addr) & IPV6_ADDR_LINKLOCAL)) {
2732                         list_move_tail(&ifa->if_list, &keep_list);
2733
2734                         /* If not doing DAD on this address, just keep it. */
2735                         if ((dev->flags&(IFF_NOARP|IFF_LOOPBACK)) ||
2736                             idev->cnf.accept_dad <= 0 ||
2737                             (ifa->flags & IFA_F_NODAD))
2738                                 continue;
2739
2740                         /* If it was tentative already, no need to notify */
2741                         if (ifa->flags & IFA_F_TENTATIVE)
2742                                 continue;
2743
2744                         /* Flag it for later restoration when link comes up */
2745                         ifa->flags |= IFA_F_TENTATIVE;
2746                         ifa->state = INET6_IFADDR_STATE_DAD;
2747                 } else {
2748                         list_del(&ifa->if_list);
2749
2750                         /* clear hash table */
2751                         spin_lock_bh(&addrconf_hash_lock);
2752                         hlist_del_init_rcu(&ifa->addr_lst);
2753                         spin_unlock_bh(&addrconf_hash_lock);
2754
2755                         write_unlock_bh(&idev->lock);
2756                         spin_lock_bh(&ifa->state_lock);
2757                         state = ifa->state;
2758                         ifa->state = INET6_IFADDR_STATE_DEAD;
2759                         spin_unlock_bh(&ifa->state_lock);
2760
2761                         if (state != INET6_IFADDR_STATE_DEAD) {
2762                                 __ipv6_ifa_notify(RTM_DELADDR, ifa);
2763                                 atomic_notifier_call_chain(&inet6addr_chain,
2764                                                            NETDEV_DOWN, ifa);
2765                         }
2766
2767                         in6_ifa_put(ifa);
2768                         write_lock_bh(&idev->lock);
2769                 }
2770         }
2771
2772         list_splice(&keep_list, &idev->addr_list);
2773
2774         write_unlock_bh(&idev->lock);
2775
2776         /* Step 5: Discard multicast list */
2777         if (how)
2778                 ipv6_mc_destroy_dev(idev);
2779         else
2780                 ipv6_mc_down(idev);
2781
2782         idev->tstamp = jiffies;
2783
2784         /* Last: Shot the device (if unregistered) */
2785         if (how) {
2786                 addrconf_sysctl_unregister(idev);
2787                 neigh_parms_release(&nd_tbl, idev->nd_parms);
2788                 neigh_ifdown(&nd_tbl, dev);
2789                 in6_dev_put(idev);
2790         }
2791         return 0;
2792 }
2793
2794 static void addrconf_rs_timer(unsigned long data)
2795 {
2796         struct inet6_ifaddr *ifp = (struct inet6_ifaddr *) data;
2797         struct inet6_dev *idev = ifp->idev;
2798
2799         read_lock(&idev->lock);
2800         if (idev->dead || !(idev->if_flags & IF_READY))
2801                 goto out;
2802
2803         if (idev->cnf.forwarding)
2804                 goto out;
2805
2806         /* Announcement received after solicitation was sent */
2807         if (idev->if_flags & IF_RA_RCVD)
2808                 goto out;
2809
2810         spin_lock(&ifp->lock);
2811         if (ifp->probes++ < idev->cnf.rtr_solicits) {
2812                 /* The wait after the last probe can be shorter */
2813                 addrconf_mod_timer(ifp, AC_RS,
2814                                    (ifp->probes == idev->cnf.rtr_solicits) ?
2815                                    idev->cnf.rtr_solicit_delay :
2816                                    idev->cnf.rtr_solicit_interval);
2817                 spin_unlock(&ifp->lock);
2818
2819                 ndisc_send_rs(idev->dev, &ifp->addr, &in6addr_linklocal_allrouters);
2820         } else {
2821                 spin_unlock(&ifp->lock);
2822                 /*
2823                  * Note: we do not support deprecated "all on-link"
2824                  * assumption any longer.
2825                  */
2826                 printk(KERN_DEBUG "%s: no IPv6 routers present\n",
2827                        idev->dev->name);
2828         }
2829
2830 out:
2831         read_unlock(&idev->lock);
2832         in6_ifa_put(ifp);
2833 }
2834
2835 /*
2836  *      Duplicate Address Detection
2837  */
2838 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
2839 {
2840         unsigned long rand_num;
2841         struct inet6_dev *idev = ifp->idev;
2842
2843         if (ifp->flags & IFA_F_OPTIMISTIC)
2844                 rand_num = 0;
2845         else
2846                 rand_num = net_random() % (idev->cnf.rtr_solicit_delay ? : 1);
2847
2848         ifp->probes = idev->cnf.dad_transmits;
2849         addrconf_mod_timer(ifp, AC_DAD, rand_num);
2850 }
2851
2852 static void addrconf_dad_start(struct inet6_ifaddr *ifp, u32 flags)
2853 {
2854         struct inet6_dev *idev = ifp->idev;
2855         struct net_device *dev = idev->dev;
2856
2857         addrconf_join_solict(dev, &ifp->addr);
2858
2859         net_srandom(ifp->addr.s6_addr32[3]);
2860
2861         read_lock_bh(&idev->lock);
2862         spin_lock(&ifp->lock);
2863         if (ifp->state == INET6_IFADDR_STATE_DEAD)
2864                 goto out;
2865
2866         if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
2867             idev->cnf.accept_dad < 1 ||
2868             !(ifp->flags&IFA_F_TENTATIVE) ||
2869             ifp->flags & IFA_F_NODAD) {
2870                 ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
2871                 spin_unlock(&ifp->lock);
2872                 read_unlock_bh(&idev->lock);
2873
2874                 addrconf_dad_completed(ifp);
2875                 return;
2876         }
2877
2878         if (!(idev->if_flags & IF_READY)) {
2879                 spin_unlock(&ifp->lock);
2880                 read_unlock_bh(&idev->lock);
2881                 /*
2882                  * If the device is not ready:
2883                  * - keep it tentative if it is a permanent address.
2884                  * - otherwise, kill it.
2885                  */
2886                 in6_ifa_hold(ifp);
2887                 addrconf_dad_stop(ifp, 0);
2888                 return;
2889         }
2890
2891         /*
2892          * Optimistic nodes can start receiving
2893          * Frames right away
2894          */
2895         if (ifp->flags & IFA_F_OPTIMISTIC)
2896                 ip6_ins_rt(ifp->rt);
2897
2898         addrconf_dad_kick(ifp);
2899 out:
2900         spin_unlock(&ifp->lock);
2901         read_unlock_bh(&idev->lock);
2902 }
2903
2904 static void addrconf_dad_timer(unsigned long data)
2905 {
2906         struct inet6_ifaddr *ifp = (struct inet6_ifaddr *) data;
2907         struct inet6_dev *idev = ifp->idev;
2908         struct in6_addr mcaddr;
2909
2910         if (!ifp->probes && addrconf_dad_end(ifp))
2911                 goto out;
2912
2913         read_lock(&idev->lock);
2914         if (idev->dead || !(idev->if_flags & IF_READY)) {
2915                 read_unlock(&idev->lock);
2916                 goto out;
2917         }
2918
2919         spin_lock(&ifp->lock);
2920         if (ifp->state == INET6_IFADDR_STATE_DEAD) {
2921                 spin_unlock(&ifp->lock);
2922                 read_unlock(&idev->lock);
2923                 goto out;
2924         }
2925
2926         if (ifp->probes == 0) {
2927                 /*
2928                  * DAD was successful
2929                  */
2930
2931                 ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
2932                 spin_unlock(&ifp->lock);
2933                 read_unlock(&idev->lock);
2934
2935                 addrconf_dad_completed(ifp);
2936
2937                 goto out;
2938         }
2939
2940         ifp->probes--;
2941         addrconf_mod_timer(ifp, AC_DAD, ifp->idev->nd_parms->retrans_time);
2942         spin_unlock(&ifp->lock);
2943         read_unlock(&idev->lock);
2944
2945         /* send a neighbour solicitation for our addr */
2946         addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
2947         ndisc_send_ns(ifp->idev->dev, NULL, &ifp->addr, &mcaddr, &in6addr_any);
2948 out:
2949         in6_ifa_put(ifp);
2950 }
2951
2952 static void addrconf_dad_completed(struct inet6_ifaddr *ifp)
2953 {
2954         struct net_device *dev = ifp->idev->dev;
2955
2956         /*
2957          *      Configure the address for reception. Now it is valid.
2958          */
2959
2960         ipv6_ifa_notify(RTM_NEWADDR, ifp);
2961
2962         /* If added prefix is link local and forwarding is off,
2963            start sending router solicitations.
2964          */
2965
2966         if ((ifp->idev->cnf.forwarding == 0 ||
2967              ifp->idev->cnf.forwarding == 2) &&
2968             ifp->idev->cnf.rtr_solicits > 0 &&
2969             (dev->flags&IFF_LOOPBACK) == 0 &&
2970             (ipv6_addr_type(&ifp->addr) & IPV6_ADDR_LINKLOCAL)) {
2971                 /*
2972                  *      If a host as already performed a random delay
2973                  *      [...] as part of DAD [...] there is no need
2974                  *      to delay again before sending the first RS
2975                  */
2976                 ndisc_send_rs(ifp->idev->dev, &ifp->addr, &in6addr_linklocal_allrouters);
2977
2978                 spin_lock_bh(&ifp->lock);
2979                 ifp->probes = 1;
2980                 ifp->idev->if_flags |= IF_RS_SENT;
2981                 addrconf_mod_timer(ifp, AC_RS, ifp->idev->cnf.rtr_solicit_interval);
2982                 spin_unlock_bh(&ifp->lock);
2983         }
2984 }
2985
2986 static void addrconf_dad_run(struct inet6_dev *idev)
2987 {
2988         struct inet6_ifaddr *ifp;
2989
2990         read_lock_bh(&idev->lock);
2991         list_for_each_entry(ifp, &idev->addr_list, if_list) {
2992                 spin_lock(&ifp->lock);
2993                 if (ifp->flags & IFA_F_TENTATIVE &&
2994                     ifp->state == INET6_IFADDR_STATE_DAD)
2995                         addrconf_dad_kick(ifp);
2996                 spin_unlock(&ifp->lock);
2997         }
2998         read_unlock_bh(&idev->lock);
2999 }
3000
3001 #ifdef CONFIG_PROC_FS
3002 struct if6_iter_state {
3003         struct seq_net_private p;
3004         int bucket;
3005 };
3006
3007 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq)
3008 {
3009         struct inet6_ifaddr *ifa = NULL;
3010         struct if6_iter_state *state = seq->private;
3011         struct net *net = seq_file_net(seq);
3012
3013         for (state->bucket = 0; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
3014                 struct hlist_node *n;
3015                 hlist_for_each_entry_rcu_bh(ifa, n, &inet6_addr_lst[state->bucket],
3016                                          addr_lst)
3017                         if (net_eq(dev_net(ifa->idev->dev), net))
3018                                 return ifa;
3019         }
3020         return NULL;
3021 }
3022
3023 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
3024                                          struct inet6_ifaddr *ifa)
3025 {
3026         struct if6_iter_state *state = seq->private;
3027         struct net *net = seq_file_net(seq);
3028         struct hlist_node *n = &ifa->addr_lst;
3029
3030         hlist_for_each_entry_continue_rcu_bh(ifa, n, addr_lst)
3031                 if (net_eq(dev_net(ifa->idev->dev), net))
3032                         return ifa;
3033
3034         while (++state->bucket < IN6_ADDR_HSIZE) {
3035                 hlist_for_each_entry_rcu_bh(ifa, n,
3036                                      &inet6_addr_lst[state->bucket], addr_lst) {
3037                         if (net_eq(dev_net(ifa->idev->dev), net))
3038                                 return ifa;
3039                 }
3040         }
3041
3042         return NULL;
3043 }
3044
3045 static struct inet6_ifaddr *if6_get_idx(struct seq_file *seq, loff_t pos)
3046 {
3047         struct inet6_ifaddr *ifa = if6_get_first(seq);
3048
3049         if (ifa)
3050                 while (pos && (ifa = if6_get_next(seq, ifa)) != NULL)
3051                         --pos;
3052         return pos ? NULL : ifa;
3053 }
3054
3055 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
3056         __acquires(rcu_bh)
3057 {
3058         rcu_read_lock_bh();
3059         return if6_get_idx(seq, *pos);
3060 }
3061
3062 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3063 {
3064         struct inet6_ifaddr *ifa;
3065
3066         ifa = if6_get_next(seq, v);
3067         ++*pos;
3068         return ifa;
3069 }
3070
3071 static void if6_seq_stop(struct seq_file *seq, void *v)
3072         __releases(rcu_bh)
3073 {
3074         rcu_read_unlock_bh();
3075 }
3076
3077 static int if6_seq_show(struct seq_file *seq, void *v)
3078 {
3079         struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
3080         seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
3081                    &ifp->addr,
3082                    ifp->idev->dev->ifindex,
3083                    ifp->prefix_len,
3084                    ifp->scope,
3085                    ifp->flags,
3086                    ifp->idev->dev->name);
3087         return 0;
3088 }
3089
3090 static const struct seq_operations if6_seq_ops = {
3091         .start  = if6_seq_start,
3092         .next   = if6_seq_next,
3093         .show   = if6_seq_show,
3094         .stop   = if6_seq_stop,
3095 };
3096
3097 static int if6_seq_open(struct inode *inode, struct file *file)
3098 {
3099         return seq_open_net(inode, file, &if6_seq_ops,
3100                             sizeof(struct if6_iter_state));
3101 }
3102
3103 static const struct file_operations if6_fops = {
3104         .owner          = THIS_MODULE,
3105         .open           = if6_seq_open,
3106         .read           = seq_read,
3107         .llseek         = seq_lseek,
3108         .release        = seq_release_net,
3109 };
3110
3111 static int __net_init if6_proc_net_init(struct net *net)
3112 {
3113         if (!proc_net_fops_create(net, "if_inet6", S_IRUGO, &if6_fops))
3114                 return -ENOMEM;
3115         return 0;
3116 }
3117
3118 static void __net_exit if6_proc_net_exit(struct net *net)
3119 {
3120        proc_net_remove(net, "if_inet6");
3121 }
3122
3123 static struct pernet_operations if6_proc_net_ops = {
3124        .init = if6_proc_net_init,
3125        .exit = if6_proc_net_exit,
3126 };
3127
3128 int __init if6_proc_init(void)
3129 {
3130         return register_pernet_subsys(&if6_proc_net_ops);
3131 }
3132
3133 void if6_proc_exit(void)
3134 {
3135         unregister_pernet_subsys(&if6_proc_net_ops);
3136 }
3137 #endif  /* CONFIG_PROC_FS */
3138
3139 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
3140 /* Check if address is a home address configured on any interface. */
3141 int ipv6_chk_home_addr(struct net *net, struct in6_addr *addr)
3142 {
3143         int ret = 0;
3144         struct inet6_ifaddr *ifp = NULL;
3145         struct hlist_node *n;
3146         unsigned int hash = ipv6_addr_hash(addr);
3147
3148         rcu_read_lock_bh();
3149         hlist_for_each_entry_rcu_bh(ifp, n, &inet6_addr_lst[hash], addr_lst) {
3150                 if (!net_eq(dev_net(ifp->idev->dev), net))