net/ipv4/devinet.c

   1 /*
   2  *      NET3    IP device support routines.
   3  *
   4  *              This program is free software; you can redistribute it and/or
   5  *              modify it under the terms of the GNU General Public License
   6  *              as published by the Free Software Foundation; either version
   7  *              2 of the License, or (at your option) any later version.
   8  *
   9  *      Derived from the IP parts of dev.c 1.0.19
  10  *              Authors:        Ross Biro
  11  *                              Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
  12  *                              Mark Evans, <evansmp@uhura.aston.ac.uk>
  13  *
  14  *      Additional Authors:
  15  *              Alan Cox, <gw4pts@gw4pts.ampr.org>
  16  *              Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
  17  *
  18  *      Changes:
  19  *              Alexey Kuznetsov:       pa_* fields are replaced with ifaddr
  20  *                                      lists.
  21  *              Cyrus Durgin:           updated for kmod
  22  *              Matthias Andree:        in devinet_ioctl, compare label and
  23  *                                      address (4.4BSD alias style support),
  24  *                                      fall back to comparing just the label
  25  *                                      if no match found.
  26  */
  27
  28
  29 #include <asm/uaccess.h>
  30 #include <linux/bitops.h>
  31 #include <linux/capability.h>
  32 #include <linux/module.h>
  33 #include <linux/types.h>
  34 #include <linux/kernel.h>
  35 #include <linux/string.h>
  36 #include <linux/mm.h>
  37 #include <linux/socket.h>
  38 #include <linux/sockios.h>
  39 #include <linux/in.h>
  40 #include <linux/errno.h>
  41 #include <linux/interrupt.h>
  42 #include <linux/if_addr.h>
  43 #include <linux/if_ether.h>
  44 #include <linux/inet.h>
  45 #include <linux/netdevice.h>
  46 #include <linux/etherdevice.h>
  47 #include <linux/skbuff.h>
  48 #include <linux/init.h>
  49 #include <linux/notifier.h>
  50 #include <linux/inetdevice.h>
  51 #include <linux/igmp.h>
  52 #include <linux/slab.h>
  53 #include <linux/hash.h>
  54 #ifdef CONFIG_SYSCTL
  55 #include <linux/sysctl.h>
  56 #endif
  57 #include <linux/kmod.h>
  58 #include <linux/netconf.h>
  59
  60 #include <net/arp.h>
  61 #include <net/ip.h>
  62 #include <net/route.h>
  63 #include <net/ip_fib.h>
  64 #include <net/rtnetlink.h>
  65 #include <net/net_namespace.h>
  66 #include <net/addrconf.h>
  67
  68 #include "fib_lookup.h"
  69
  70 static struct ipv4_devconf ipv4_devconf = {
  71         .data = {
  72                 [IPV4_DEVCONF_ACCEPT_REDIRECTS - 1] = 1,
  73                 [IPV4_DEVCONF_SEND_REDIRECTS - 1] = 1,
  74                 [IPV4_DEVCONF_SECURE_REDIRECTS - 1] = 1,
  75                 [IPV4_DEVCONF_SHARED_MEDIA - 1] = 1,
  76                 [IPV4_DEVCONF_IGMPV2_UNSOLICITED_REPORT_INTERVAL - 1] = 10000 /*ms*/,
  77                 [IPV4_DEVCONF_IGMPV3_UNSOLICITED_REPORT_INTERVAL - 1] =  1000 /*ms*/,
  78         },
  79 };
  80
  81 static struct ipv4_devconf ipv4_devconf_dflt = {
  82         .data = {
  83                 [IPV4_DEVCONF_ACCEPT_REDIRECTS - 1] = 1,
  84                 [IPV4_DEVCONF_SEND_REDIRECTS - 1] = 1,
  85                 [IPV4_DEVCONF_SECURE_REDIRECTS - 1] = 1,
  86                 [IPV4_DEVCONF_SHARED_MEDIA - 1] = 1,
  87                 [IPV4_DEVCONF_ACCEPT_SOURCE_ROUTE - 1] = 1,
  88                 [IPV4_DEVCONF_IGMPV2_UNSOLICITED_REPORT_INTERVAL - 1] = 10000 /*ms*/,
  89                 [IPV4_DEVCONF_IGMPV3_UNSOLICITED_REPORT_INTERVAL - 1] =  1000 /*ms*/,
  90         },
  91 };
  92
  93 #define IPV4_DEVCONF_DFLT(net, attr) \
  94         IPV4_DEVCONF((*net->ipv4.devconf_dflt), attr)
  95
  96 static const struct nla_policy ifa_ipv4_policy[IFA_MAX+1] = {
  97         [IFA_LOCAL]             = { .type = NLA_U32 },
  98         [IFA_ADDRESS]           = { .type = NLA_U32 },
  99         [IFA_BROADCAST]         = { .type = NLA_U32 },
 100         [IFA_LABEL]             = { .type = NLA_STRING, .len = IFNAMSIZ - 1 },
 101         [IFA_CACHEINFO]         = { .len = sizeof(struct ifa_cacheinfo) },
 102         [IFA_FLAGS]             = { .type = NLA_U32 },
 103 };
 104
 105 #define IN4_ADDR_HSIZE_SHIFT    8
 106 #define IN4_ADDR_HSIZE          (1U << IN4_ADDR_HSIZE_SHIFT)
 107
 108 static struct hlist_head inet_addr_lst[IN4_ADDR_HSIZE];
 109 static DEFINE_SPINLOCK(inet_addr_hash_lock);
 110
 111 static u32 inet_addr_hash(struct net *net, __be32 addr)
 112 {
 113         u32 val = (__force u32) addr ^ net_hash_mix(net);
 114
 115         return hash_32(val, IN4_ADDR_HSIZE_SHIFT);
 116 }
 117
 118 static void inet_hash_insert(struct net *net, struct in_ifaddr *ifa)
 119 {
 120         u32 hash = inet_addr_hash(net, ifa->ifa_local);
 121
 122         spin_lock(&inet_addr_hash_lock);
 123         hlist_add_head_rcu(&ifa->hash, &inet_addr_lst[hash]);
 124         spin_unlock(&inet_addr_hash_lock);
 125 }
 126
 127 static void inet_hash_remove(struct in_ifaddr *ifa)
 128 {
 129         spin_lock(&inet_addr_hash_lock);
 130         hlist_del_init_rcu(&ifa->hash);
 131         spin_unlock(&inet_addr_hash_lock);
 132 }
 133
 134 /**
 135  * __ip_dev_find - find the first device with a given source address.
 136  * @net: the net namespace
 137  * @addr: the source address
 138  * @devref: if true, take a reference on the found device
 139  *
 140  * If a caller uses devref=false, it should be protected by RCU, or RTNL
 141  */
 142 struct net_device *__ip_dev_find(struct net *net, __be32 addr, bool devref)
 143 {
 144         u32 hash = inet_addr_hash(net, addr);
 145         struct net_device *result = NULL;
 146         struct in_ifaddr *ifa;
 147
 148         rcu_read_lock();
 149         hlist_for_each_entry_rcu(ifa, &inet_addr_lst[hash], hash) {
 150                 if (ifa->ifa_local == addr) {
 151                         struct net_device *dev = ifa->ifa_dev->dev;
 152
 153                         if (!net_eq(dev_net(dev), net))
 154                                 continue;
 155                         result = dev;
 156                         break;
 157                 }
 158         }
 159         if (!result) {
 160                 struct flowi4 fl4 = { .daddr = addr };
 161                 struct fib_result res = { 0 };
 162                 struct fib_table *local;
 163
 164                 /* Fallback to FIB local table so that communication
 165                  * over loopback subnets work.
 166                  */
 167                 local = fib_get_table(net, RT_TABLE_LOCAL);
 168                 if (local &&
 169                     !fib_table_lookup(local, &fl4, &res, FIB_LOOKUP_NOREF) &&
 170                     res.type == RTN_LOCAL)
 171                         result = FIB_RES_DEV(res);
 172         }
 173         if (result && devref)
 174                 dev_hold(result);
 175         rcu_read_unlock();
 176         return result;
 177 }
 178 EXPORT_SYMBOL(__ip_dev_find);
 179
 180 static void rtmsg_ifa(int event, struct in_ifaddr *, struct nlmsghdr *, u32);
 181
 182 static BLOCKING_NOTIFIER_HEAD(inetaddr_chain);
 183 static void inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap,
 184                          int destroy);
 185 #ifdef CONFIG_SYSCTL
 186 static void devinet_sysctl_register(struct in_device *idev);
 187 static void devinet_sysctl_unregister(struct in_device *idev);
 188 #else
 189 static void devinet_sysctl_register(struct in_device *idev)
 190 {
 191 }
 192 static void devinet_sysctl_unregister(struct in_device *idev)
 193 {
 194 }
 195 #endif
 196
 197 /* Locks all the inet devices. */
 198
 199 static struct in_ifaddr *inet_alloc_ifa(void)
 200 {
 201         return kzalloc(sizeof(struct in_ifaddr), GFP_KERNEL);
 202 }
 203
 204 static void inet_rcu_free_ifa(struct rcu_head *head)
 205 {
 206         struct in_ifaddr *ifa = container_of(head, struct in_ifaddr, rcu_head);
 207         if (ifa->ifa_dev)
 208                 in_dev_put(ifa->ifa_dev);
 209         kfree(ifa);
 210 }
 211
 212 static void inet_free_ifa(struct in_ifaddr *ifa)
 213 {
 214         call_rcu(&ifa->rcu_head, inet_rcu_free_ifa);
 215 }
 216
 217 void in_dev_finish_destroy(struct in_device *idev)
 218 {
 219         struct net_device *dev = idev->dev;
 220
 221         WARN_ON(idev->ifa_list);
 222         WARN_ON(idev->mc_list);
 223         kfree(rcu_dereference_protected(idev->mc_hash, 1));
 224 #ifdef NET_REFCNT_DEBUG
 225         pr_debug("%s: %p=%s\n", __func__, idev, dev ? dev->name : "NIL");
 226 #endif
 227         dev_put(dev);
 228         if (!idev->dead)
 229                 pr_err("Freeing alive in_device %p\n", idev);
 230         else
 231                 kfree(idev);
 232 }
 233 EXPORT_SYMBOL(in_dev_finish_destroy);
 234
 235 static struct in_device *inetdev_init(struct net_device *dev)
 236 {
 237         struct in_device *in_dev;
 238
 239         ASSERT_RTNL();
 240
 241         in_dev = kzalloc(sizeof(*in_dev), GFP_KERNEL);
 242         if (!in_dev)
 243                 goto out;
 244         memcpy(&in_dev->cnf, dev_net(dev)->ipv4.devconf_dflt,
 245                         sizeof(in_dev->cnf));
 246         in_dev->cnf.sysctl = NULL;
 247         in_dev->dev = dev;
 248         in_dev->arp_parms = neigh_parms_alloc(dev, &arp_tbl);
 249         if (!in_dev->arp_parms)
 250                 goto out_kfree;
 251         if (IPV4_DEVCONF(in_dev->cnf, FORWARDING))
 252                 dev_disable_lro(dev);
 253         /* Reference in_dev->dev */
 254         dev_hold(dev);
 255         /* Account for reference dev->ip_ptr (below) */
 256         in_dev_hold(in_dev);
 257
 258         devinet_sysctl_register(in_dev);
 259         ip_mc_init_dev(in_dev);
 260         if (dev->flags & IFF_UP)
 261                 ip_mc_up(in_dev);
 262
 263         /* we can receive as soon as ip_ptr is set -- do this last */
 264         rcu_assign_pointer(dev->ip_ptr, in_dev);
 265 out:
 266         return in_dev;
 267 out_kfree:
 268         kfree(in_dev);
 269         in_dev = NULL;
 270         goto out;
 271 }
 272
 273 static void in_dev_rcu_put(struct rcu_head *head)
 274 {
 275         struct in_device *idev = container_of(head, struct in_device, rcu_head);
 276         in_dev_put(idev);
 277 }
 278
 279 static void inetdev_destroy(struct in_device *in_dev)
 280 {
 281         struct in_ifaddr *ifa;
 282         struct net_device *dev;
 283
 284         ASSERT_RTNL();
 285
 286         dev = in_dev->dev;
 287
 288         in_dev->dead = 1;
 289
 290         ip_mc_destroy_dev(in_dev);
 291
 292         while ((ifa = in_dev->ifa_list) != NULL) {
 293                 inet_del_ifa(in_dev, &in_dev->ifa_list, 0);
 294                 inet_free_ifa(ifa);
 295         }
 296
 297         RCU_INIT_POINTER(dev->ip_ptr, NULL);
 298
 299         devinet_sysctl_unregister(in_dev);
 300         neigh_parms_release(&arp_tbl, in_dev->arp_parms);
 301         arp_ifdown(dev);
 302
 303         call_rcu(&in_dev->rcu_head, in_dev_rcu_put);
 304 }
 305
 306 int inet_addr_onlink(struct in_device *in_dev, __be32 a, __be32 b)
 307 {
 308         rcu_read_lock();
 309         for_primary_ifa(in_dev) {
 310                 if (inet_ifa_match(a, ifa)) {
 311                         if (!b || inet_ifa_match(b, ifa)) {
 312                                 rcu_read_unlock();
 313                                 return 1;
 314                         }
 315                 }
 316         } endfor_ifa(in_dev);
 317         rcu_read_unlock();
 318         return 0;
 319 }
 320
 321 static void __inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap,
 322                          int destroy, struct nlmsghdr *nlh, u32 portid)
 323 {
 324         struct in_ifaddr *promote = NULL;
 325         struct in_ifaddr *ifa, *ifa1 = *ifap;
 326         struct in_ifaddr *last_prim = in_dev->ifa_list;
 327         struct in_ifaddr *prev_prom = NULL;
 328         int do_promote = IN_DEV_PROMOTE_SECONDARIES(in_dev);
 329
 330         ASSERT_RTNL();
 331
 332         /* 1. Deleting primary ifaddr forces deletion all secondaries
 333          * unless alias promotion is set
 334          **/
 335
 336         if (!(ifa1->ifa_flags & IFA_F_SECONDARY)) {
 337                 struct in_ifaddr **ifap1 = &ifa1->ifa_next;
 338
 339                 while ((ifa = *ifap1) != NULL) {
 340                         if (!(ifa->ifa_flags & IFA_F_SECONDARY) &&
 341                             ifa1->ifa_scope <= ifa->ifa_scope)
 342                                 last_prim = ifa;
 343
 344                         if (!(ifa->ifa_flags & IFA_F_SECONDARY) ||
 345                             ifa1->ifa_mask != ifa->ifa_mask ||
 346                             !inet_ifa_match(ifa1->ifa_address, ifa)) {
 347                                 ifap1 = &ifa->ifa_next;
 348                                 prev_prom = ifa;
 349                                 continue;
 350                         }
 351
 352                         if (!do_promote) {
 353                                 inet_hash_remove(ifa);
 354                                 *ifap1 = ifa->ifa_next;
 355
 356                                 rtmsg_ifa(RTM_DELADDR, ifa, nlh, portid);
 357                                 blocking_notifier_call_chain(&inetaddr_chain,
 358                                                 NETDEV_DOWN, ifa);
 359                                 inet_free_ifa(ifa);
 360                         } else {
 361                                 promote = ifa;
 362                                 break;
 363                         }
 364                 }
 365         }
 366
 367         /* On promotion all secondaries from subnet are changing
 368          * the primary IP, we must remove all their routes silently
 369          * and later to add them back with new prefsrc. Do this
 370          * while all addresses are on the device list.
 371          */
 372         for (ifa = promote; ifa; ifa = ifa->ifa_next) {
 373                 if (ifa1->ifa_mask == ifa->ifa_mask &&
 374                     inet_ifa_match(ifa1->ifa_address, ifa))
 375                         fib_del_ifaddr(ifa, ifa1);
 376         }
 377
 378         /* 2. Unlink it */
 379
 380         *ifap = ifa1->ifa_next;
 381         inet_hash_remove(ifa1);
 382
 383         /* 3. Announce address deletion */
 384
 385         /* Send message first, then call notifier.
 386            At first sight, FIB update triggered by notifier
 387            will refer to already deleted ifaddr, that could confuse
 388            netlink listeners. It is not true: look, gated sees
 389            that route deleted and if it still thinks that ifaddr
 390            is valid, it will try to restore deleted routes... Grr.
 391            So that, this order is correct.
 392          */
 393         rtmsg_ifa(RTM_DELADDR, ifa1, nlh, portid);
 394         blocking_notifier_call_chain(&inetaddr_chain, NETDEV_DOWN, ifa1);
 395
 396         if (promote) {
 397                 struct in_ifaddr *next_sec = promote->ifa_next;
 398
 399                 if (prev_prom) {
 400                         prev_prom->ifa_next = promote->ifa_next;
 401                         promote->ifa_next = last_prim->ifa_next;
 402                         last_prim->ifa_next = promote;
 403                 }
 404
 405                 promote->ifa_flags &= ~IFA_F_SECONDARY;
 406                 rtmsg_ifa(RTM_NEWADDR, promote, nlh, portid);
 407                 blocking_notifier_call_chain(&inetaddr_chain,
 408                                 NETDEV_UP, promote);
 409                 for (ifa = next_sec; ifa; ifa = ifa->ifa_next) {
 410                         if (ifa1->ifa_mask != ifa->ifa_mask ||
 411                             !inet_ifa_match(ifa1->ifa_address, ifa))
 412                                         continue;
 413                         fib_add_ifaddr(ifa);
 414                 }
 415
 416         }
 417         if (destroy)
 418                 inet_free_ifa(ifa1);
 419 }
 420
 421 static void inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap,
 422                          int destroy)
 423 {
 424         __inet_del_ifa(in_dev, ifap, destroy, NULL, 0);
 425 }
 426
 427 static void check_lifetime(struct work_struct *work);
 428
 429 static DECLARE_DELAYED_WORK(check_lifetime_work, check_lifetime);
 430
 431 static int __inet_insert_ifa(struct in_ifaddr *ifa, struct nlmsghdr *nlh,
 432                              u32 portid)
 433 {
 434         struct in_device *in_dev = ifa->ifa_dev;
 435         struct in_ifaddr *ifa1, **ifap, **last_primary;
 436
 437         ASSERT_RTNL();
 438
 439         if (!ifa->ifa_local) {
 440                 inet_free_ifa(ifa);
 441                 return 0;
 442         }
 443
 444         ifa->ifa_flags &= ~IFA_F_SECONDARY;
 445         last_primary = &in_dev->ifa_list;
 446
 447         for (ifap = &in_dev->ifa_list; (ifa1 = *ifap) != NULL;
 448              ifap = &ifa1->ifa_next) {
 449                 if (!(ifa1->ifa_flags & IFA_F_SECONDARY) &&
 450                     ifa->ifa_scope <= ifa1->ifa_scope)
 451                         last_primary = &ifa1->ifa_next;
 452                 if (ifa1->ifa_mask == ifa->ifa_mask &&
 453                     inet_ifa_match(ifa1->ifa_address, ifa)) {
 454                         if (ifa1->ifa_local == ifa->ifa_local) {
 455                                 inet_free_ifa(ifa);
 456                                 return -EEXIST;
 457                         }
 458                         if (ifa1->ifa_scope != ifa->ifa_scope) {
 459                                 inet_free_ifa(ifa);
 460                                 return -EINVAL;
 461                         }
 462                         ifa->ifa_flags |= IFA_F_SECONDARY;
 463                 }
 464         }
 465
 466         if (!(ifa->ifa_flags & IFA_F_SECONDARY)) {
 467                 net_srandom(ifa->ifa_local);
 468                 ifap = last_primary;
 469         }
 470
 471         ifa->ifa_next = *ifap;
 472         *ifap = ifa;
 473
 474         inet_hash_insert(dev_net(in_dev->dev), ifa);
 475
 476         cancel_delayed_work(&check_lifetime_work);
 477         schedule_delayed_work(&check_lifetime_work, 0);
 478
 479         /* Send message first, then call notifier.
 480            Notifier will trigger FIB update, so that
 481            listeners of netlink will know about new ifaddr */
 482         rtmsg_ifa(RTM_NEWADDR, ifa, nlh, portid);
 483         blocking_notifier_call_chain(&inetaddr_chain, NETDEV_UP, ifa);
 484
 485         return 0;
 486 }
 487
 488 static int inet_insert_ifa(struct in_ifaddr *ifa)
 489 {
 490         return __inet_insert_ifa(ifa, NULL, 0);
 491 }
 492
 493 static int inet_set_ifa(struct net_device *dev, struct in_ifaddr *ifa)
 494 {
 495         struct in_device *in_dev = __in_dev_get_rtnl(dev);
 496
 497         ASSERT_RTNL();
 498
 499         if (!in_dev) {
 500                 inet_free_ifa(ifa);
 501                 return -ENOBUFS;
 502         }
 503         ipv4_devconf_setall(in_dev);
 504         neigh_parms_data_state_setall(in_dev->arp_parms);
 505         if (ifa->ifa_dev != in_dev) {
 506                 WARN_ON(ifa->ifa_dev);
 507                 in_dev_hold(in_dev);
 508                 ifa->ifa_dev = in_dev;
 509         }
 510         if (ipv4_is_loopback(ifa->ifa_local))
 511                 ifa->ifa_scope = RT_SCOPE_HOST;
 512         return inet_insert_ifa(ifa);
 513 }
 514
 515 /* Caller must hold RCU or RTNL :
 516  * We dont take a reference on found in_device
 517  */
 518 struct in_device *inetdev_by_index(struct net *net, int ifindex)
 519 {
 520         struct net_device *dev;
 521         struct in_device *in_dev = NULL;
 522
 523         rcu_read_lock();
 524         dev = dev_get_by_index_rcu(net, ifindex);
 525         if (dev)
 526                 in_dev = rcu_dereference_rtnl(dev->ip_ptr);
 527         rcu_read_unlock();
 528         return in_dev;
 529 }
 530 EXPORT_SYMBOL(inetdev_by_index);
 531
 532 /* Called only from RTNL semaphored context. No locks. */
 533
 534 struct in_ifaddr *inet_ifa_byprefix(struct in_device *in_dev, __be32 prefix,
 535                                     __be32 mask)
 536 {
 537         ASSERT_RTNL();
 538
 539         for_primary_ifa(in_dev) {
 540                 if (ifa->ifa_mask == mask && inet_ifa_match(prefix, ifa))
 541                         return ifa;
 542         } endfor_ifa(in_dev);
 543         return NULL;
 544 }
 545
 546 static int inet_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh)
 547 {
 548         struct net *net = sock_net(skb->sk);
 549         struct nlattr *tb[IFA_MAX+1];
 550         struct in_device *in_dev;
 551         struct ifaddrmsg *ifm;
 552         struct in_ifaddr *ifa, **ifap;
 553         int err = -EINVAL;
 554
 555         ASSERT_RTNL();
 556
 557         err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv4_policy);
 558         if (err < 0)
 559                 goto errout;
 560
 561         ifm = nlmsg_data(nlh);
 562         in_dev = inetdev_by_index(net, ifm->ifa_index);
 563         if (in_dev == NULL) {
 564                 err = -ENODEV;
 565                 goto errout;
 566         }
 567
 568         for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL;
 569              ifap = &ifa->ifa_next) {
 570                 if (tb[IFA_LOCAL] &&
 571                     ifa->ifa_local != nla_get_be32(tb[IFA_LOCAL]))
 572                         continue;
 573
 574                 if (tb[IFA_LABEL] && nla_strcmp(tb[IFA_LABEL], ifa->ifa_label))
 575                         continue;
 576
 577                 if (tb[IFA_ADDRESS] &&
 578                     (ifm->ifa_prefixlen != ifa->ifa_prefixlen ||
 579                     !inet_ifa_match(nla_get_be32(tb[IFA_ADDRESS]), ifa)))
 580                         continue;
 581
 582                 __inet_del_ifa(in_dev, ifap, 1, nlh, NETLINK_CB(skb).portid);
 583                 return 0;
 584         }
 585
 586         err = -EADDRNOTAVAIL;
 587 errout:
 588         return err;
 589 }
 590
 591 #define INFINITY_LIFE_TIME      0xFFFFFFFF
 592
 593 static void check_lifetime(struct work_struct *work)
 594 {
 595         unsigned long now, next, next_sec, next_sched;
 596         struct in_ifaddr *ifa;
 597         struct hlist_node *n;
 598         int i;
 599
 600         now = jiffies;
 601         next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
 602
 603         for (i = 0; i < IN4_ADDR_HSIZE; i++) {
 604                 bool change_needed = false;
 605
 606                 rcu_read_lock();
 607                 hlist_for_each_entry_rcu(ifa, &inet_addr_lst[i], hash) {
 608                         unsigned long age;
 609
 610                         if (ifa->ifa_flags & IFA_F_PERMANENT)
 611                                 continue;
 612
 613                         /* We try to batch several events at once. */
 614                         age = (now - ifa->ifa_tstamp +
 615                                ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
 616
 617                         if (ifa->ifa_valid_lft != INFINITY_LIFE_TIME &&
 618                             age >= ifa->ifa_valid_lft) {
 619                                 change_needed = true;
 620                         } else if (ifa->ifa_preferred_lft ==
 621                                    INFINITY_LIFE_TIME) {
 622                                 continue;
 623                         } else if (age >= ifa->ifa_preferred_lft) {
 624                                 if (time_before(ifa->ifa_tstamp +
 625                                                 ifa->ifa_valid_lft * HZ, next))
 626                                         next = ifa->ifa_tstamp +
 627                                                ifa->ifa_valid_lft * HZ;
 628
 629                                 if (!(ifa->ifa_flags & IFA_F_DEPRECATED))
 630                                         change_needed = true;
 631                         } else if (time_before(ifa->ifa_tstamp +
 632                                                ifa->ifa_preferred_lft * HZ,
 633                                                next)) {
 634                                 next = ifa->ifa_tstamp +
 635                                        ifa->ifa_preferred_lft * HZ;
 636                         }
 637                 }
 638                 rcu_read_unlock();
 639                 if (!change_needed)
 640                         continue;
 641                 rtnl_lock();
 642                 hlist_for_each_entry_safe(ifa, n, &inet_addr_lst[i], hash) {
 643                         unsigned long age;
 644
 645                         if (ifa->ifa_flags & IFA_F_PERMANENT)
 646                                 continue;
 647
 648                         /* We try to batch several events at once. */
 649                         age = (now - ifa->ifa_tstamp +
 650                                ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
 651
 652                         if (ifa->ifa_valid_lft != INFINITY_LIFE_TIME &&
 653                             age >= ifa->ifa_valid_lft) {
 654                                 struct in_ifaddr **ifap;
 655
 656                                 for (ifap = &ifa->ifa_dev->ifa_list;
 657                                      *ifap != NULL; ifap = &(*ifap)->ifa_next) {
 658                                         if (*ifap == ifa) {
 659                                                 inet_del_ifa(ifa->ifa_dev,
 660                                                              ifap, 1);
 661                                                 break;
 662                                         }
 663                                 }
 664                         } else if (ifa->ifa_preferred_lft !=
 665                                    INFINITY_LIFE_TIME &&
 666                                    age >= ifa->ifa_preferred_lft &&
 667                                    !(ifa->ifa_flags & IFA_F_DEPRECATED)) {
 668                                 ifa->ifa_flags |= IFA_F_DEPRECATED;
 669                                 rtmsg_ifa(RTM_NEWADDR, ifa, NULL, 0);
 670                         }
 671                 }
 672                 rtnl_unlock();
 673         }
 674
 675         next_sec = round_jiffies_up(next);
 676         next_sched = next;
 677
 678         /* If rounded timeout is accurate enough, accept it. */
 679         if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
 680                 next_sched = next_sec;
 681
 682         now = jiffies;
 683         /* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
 684         if (time_before(next_sched, now + ADDRCONF_TIMER_FUZZ_MAX))
 685                 next_sched = now + ADDRCONF_TIMER_FUZZ_MAX;
 686
 687         schedule_delayed_work(&check_lifetime_work, next_sched - now);
 688 }
 689
 690 static void set_ifa_lifetime(struct in_ifaddr *ifa, __u32 valid_lft,
 691                              __u32 prefered_lft)
 692 {
 693         unsigned long timeout;
 694
 695         ifa->ifa_flags &= ~(IFA_F_PERMANENT | IFA_F_DEPRECATED);
 696
 697         timeout = addrconf_timeout_fixup(valid_lft, HZ);
 698         if (addrconf_finite_timeout(timeout))
 699                 ifa->ifa_valid_lft = timeout;
 700         else
 701                 ifa->ifa_flags |= IFA_F_PERMANENT;
 702
 703         timeout = addrconf_timeout_fixup(prefered_lft, HZ);
 704         if (addrconf_finite_timeout(timeout)) {
 705                 if (timeout == 0)
 706                         ifa->ifa_flags |= IFA_F_DEPRECATED;
 707                 ifa->ifa_preferred_lft = timeout;
 708         }
 709         ifa->ifa_tstamp = jiffies;
 710         if (!ifa->ifa_cstamp)
 711                 ifa->ifa_cstamp = ifa->ifa_tstamp;
 712 }
 713
 714 static struct in_ifaddr *rtm_to_ifaddr(struct net *net, struct nlmsghdr *nlh,
 715                                        __u32 *pvalid_lft, __u32 *pprefered_lft)
 716 {
 717         struct nlattr *tb[IFA_MAX+1];
 718         struct in_ifaddr *ifa;
 719         struct ifaddrmsg *ifm;
 720         struct net_device *dev;
 721         struct in_device *in_dev;
 722         int err;
 723
 724         err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv4_policy);
 725         if (err < 0)
 726                 goto errout;
 727
 728         ifm = nlmsg_data(nlh);
 729         err = -EINVAL;
 730         if (ifm->ifa_prefixlen > 32 || tb[IFA_LOCAL] == NULL)
 731                 goto errout;
 732
 733         dev = __dev_get_by_index(net, ifm->ifa_index);
 734         err = -ENODEV;
 735         if (dev == NULL)
 736                 goto errout;
 737
 738         in_dev = __in_dev_get_rtnl(dev);
 739         err = -ENOBUFS;
 740         if (in_dev == NULL)
 741                 goto errout;
 742
 743         ifa = inet_alloc_ifa();
 744         if (ifa == NULL)
 745                 /*
 746                  * A potential indev allocation can be left alive, it stays
 747                  * assigned to its device and is destroy with it.
 748                  */
 749                 goto errout;
 750
 751         ipv4_devconf_setall(in_dev);
 752         neigh_parms_data_state_setall(in_dev->arp_parms);
 753         in_dev_hold(in_dev);
 754
 755         if (tb[IFA_ADDRESS] == NULL)
 756                 tb[IFA_ADDRESS] = tb[IFA_LOCAL];
 757
 758         INIT_HLIST_NODE(&ifa->hash);
 759         ifa->ifa_prefixlen = ifm->ifa_prefixlen;
 760         ifa->ifa_mask = inet_make_mask(ifm->ifa_prefixlen);
 761         ifa->ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) :
 762                                          ifm->ifa_flags;
 763         ifa->ifa_scope = ifm->ifa_scope;
 764         ifa->ifa_dev = in_dev;
 765
 766         ifa->ifa_local = nla_get_be32(tb[IFA_LOCAL]);
 767         ifa->ifa_address = nla_get_be32(tb[IFA_ADDRESS]);
 768
 769         if (tb[IFA_BROADCAST])
 770                 ifa->ifa_broadcast = nla_get_be32(tb[IFA_BROADCAST]);
 771
 772         if (tb[IFA_LABEL])
 773                 nla_strlcpy(ifa->ifa_label, tb[IFA_LABEL], IFNAMSIZ);
 774         else
 775                 memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
 776
 777         if (tb[IFA_CACHEINFO]) {
 778                 struct ifa_cacheinfo *ci;
 779
 780                 ci = nla_data(tb[IFA_CACHEINFO]);
 781                 if (!ci->ifa_valid || ci->ifa_prefered > ci->ifa_valid) {
 782                         err = -EINVAL;
 783                         goto errout_free;
 784                 }
 785                 *pvalid_lft = ci->ifa_valid;
 786                 *pprefered_lft = ci->ifa_prefered;
 787         }
 788
 789         return ifa;
 790
 791 errout_free:
 792         inet_free_ifa(ifa);
 793 errout:
 794         return ERR_PTR(err);
 795 }
 796
 797 static struct in_ifaddr *find_matching_ifa(struct in_ifaddr *ifa)
 798 {
 799         struct in_device *in_dev = ifa->ifa_dev;
 800         struct in_ifaddr *ifa1, **ifap;
 801
 802         if (!ifa->ifa_local)
 803                 return NULL;
 804
 805         for (ifap = &in_dev->ifa_list; (ifa1 = *ifap) != NULL;
 806              ifap = &ifa1->ifa_next) {
 807                 if (ifa1->ifa_mask == ifa->ifa_mask &&
 808                     inet_ifa_match(ifa1->ifa_address, ifa) &&
 809                     ifa1->ifa_local == ifa->ifa_local)
 810                         return ifa1;
 811         }
 812         return NULL;
 813 }
 814
 815 static int inet_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh)
 816 {
 817         struct net *net = sock_net(skb->sk);
 818         struct in_ifaddr *ifa;
 819         struct in_ifaddr *ifa_existing;
 820         __u32 valid_lft = INFINITY_LIFE_TIME;
 821         __u32 prefered_lft = INFINITY_LIFE_TIME;
 822
 823         ASSERT_RTNL();
 824
 825         ifa = rtm_to_ifaddr(net, nlh, &valid_lft, &prefered_lft);
 826         if (IS_ERR(ifa))
 827                 return PTR_ERR(ifa);
 828
 829         ifa_existing = find_matching_ifa(ifa);
 830         if (!ifa_existing) {
 831                 /* It would be best to check for !NLM_F_CREATE here but
 832                  * userspace alreay relies on not having to provide this.
 833                  */
 834                 set_ifa_lifetime(ifa, valid_lft, prefered_lft);
 835                 return __inet_insert_ifa(ifa, nlh, NETLINK_CB(skb).portid);
 836         } else {
 837                 inet_free_ifa(ifa);
 838
 839                 if (nlh->nlmsg_flags & NLM_F_EXCL ||
 840                     !(nlh->nlmsg_flags & NLM_F_REPLACE))
 841                         return -EEXIST;
 842                 ifa = ifa_existing;
 843                 set_ifa_lifetime(ifa, valid_lft, prefered_lft);
 844                 cancel_delayed_work(&check_lifetime_work);
 845                 schedule_delayed_work(&check_lifetime_work, 0);
 846                 rtmsg_ifa(RTM_NEWADDR, ifa, nlh, NETLINK_CB(skb).portid);
 847                 blocking_notifier_call_chain(&inetaddr_chain, NETDEV_UP, ifa);
 848         }
 849         return 0;
 850 }
 851
 852 /*
 853  *      Determine a default network mask, based on the IP address.
 854  */
 855
 856 static int inet_abc_len(__be32 addr)
 857 {
 858         int rc = -1;    /* Something else, probably a multicast. */
 859
 860         if (ipv4_is_zeronet(addr))
 861                 rc = 0;
 862         else {
 863                 __u32 haddr = ntohl(addr);
 864
 865                 if (IN_CLASSA(haddr))
 866                         rc = 8;
 867                 else if (IN_CLASSB(haddr))
 868                         rc = 16;
 869                 else if (IN_CLASSC(haddr))
 870                         rc = 24;
 871         }
 872
 873         return rc;
 874 }
 875
 876
 877 int devinet_ioctl(struct net *net, unsigned int cmd, void __user *arg)
 878 {
 879         struct ifreq ifr;
 880         struct sockaddr_in sin_orig;
 881         struct sockaddr_in *sin = (struct sockaddr_in *)&ifr.ifr_addr;
 882         struct in_device *in_dev;
 883         struct in_ifaddr **ifap = NULL;
 884         struct in_ifaddr *ifa = NULL;
 885         struct net_device *dev;
 886         char *colon;
 887         int ret = -EFAULT;
 888         int tryaddrmatch = 0;
 889
 890         /*
 891          *      Fetch the caller's info block into kernel space
 892          */
 893
 894         if (copy_from_user(&ifr, arg, sizeof(struct ifreq)))
 895                 goto out;
 896         ifr.ifr_name[IFNAMSIZ - 1] = 0;
 897
 898         /* save original address for comparison */
 899         memcpy(&sin_orig, sin, sizeof(*sin));
 900
 901         colon = strchr(ifr.ifr_name, ':');
 902         if (colon)
 903                 *colon = 0;
 904
 905         dev_load(net, ifr.ifr_name);
 906
 907         switch (cmd) {
 908         case SIOCGIFADDR:       /* Get interface address */
 909         case SIOCGIFBRDADDR:    /* Get the broadcast address */
 910         case SIOCGIFDSTADDR:    /* Get the destination address */
 911         case SIOCGIFNETMASK:    /* Get the netmask for the interface */
 912                 /* Note that these ioctls will not sleep,
 913                    so that we do not impose a lock.
 914                    One day we will be forced to put shlock here (I mean SMP)
 915                  */
 916                 tryaddrmatch = (sin_orig.sin_family == AF_INET);
 917                 memset(sin, 0, sizeof(*sin));
 918                 sin->sin_family = AF_INET;
 919                 break;
 920
 921         case SIOCSIFFLAGS:
 922                 ret = -EPERM;
 923                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
 924                         goto out;
 925                 break;
 926         case SIOCSIFADDR:       /* Set interface address (and family) */
 927         case SIOCSIFBRDADDR:    /* Set the broadcast address */
 928         case SIOCSIFDSTADDR:    /* Set the destination address */
 929         case SIOCSIFNETMASK:    /* Set the netmask for the interface */
 930                 ret = -EPERM;
 931                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
 932                         goto out;
 933                 ret = -EINVAL;
 934                 if (sin->sin_family != AF_INET)
 935                         goto out;
 936                 break;
 937         default:
 938                 ret = -EINVAL;
 939                 goto out;
 940         }
 941
 942         rtnl_lock();
 943
 944         ret = -ENODEV;
 945         dev = __dev_get_by_name(net, ifr.ifr_name);
 946         if (!dev)
 947                 goto done;
 948
 949         if (colon)
 950                 *colon = ':';
 951
 952         in_dev = __in_dev_get_rtnl(dev);
 953         if (in_dev) {
 954                 if (tryaddrmatch) {
 955                         /* Matthias Andree */
 956                         /* compare label and address (4.4BSD style) */
 957                         /* note: we only do this for a limited set of ioctls
 958                            and only if the original address family was AF_INET.
 959                            This is checked above. */
 960                         for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL;
 961                              ifap = &ifa->ifa_next) {
 962                                 if (!strcmp(ifr.ifr_name, ifa->ifa_label) &&
 963                                     sin_orig.sin_addr.s_addr ==
 964                                                         ifa->ifa_local) {
 965                                         break; /* found */
 966                                 }
 967                         }
 968                 }
 969                 /* we didn't get a match, maybe the application is
 970                    4.3BSD-style and passed in junk so we fall back to
 971                    comparing just the label */
 972                 if (!ifa) {
 973                         for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL;
 974                              ifap = &ifa->ifa_next)
 975                                 if (!strcmp(ifr.ifr_name, ifa->ifa_label))
 976                                         break;
 977                 }
 978         }
 979
 980         ret = -EADDRNOTAVAIL;
 981         if (!ifa && cmd != SIOCSIFADDR && cmd != SIOCSIFFLAGS)
 982                 goto done;
 983
 984         switch (cmd) {
 985         case SIOCGIFADDR:       /* Get interface address */
 986                 sin->sin_addr.s_addr = ifa->ifa_local;
 987                 goto rarok;
 988
 989         case SIOCGIFBRDADDR:    /* Get the broadcast address */
 990                 sin->sin_addr.s_addr = ifa->ifa_broadcast;
 991                 goto rarok;
 992
 993         case SIOCGIFDSTADDR:    /* Get the destination address */
 994                 sin->sin_addr.s_addr = ifa->ifa_address;
 995                 goto rarok;
 996
 997         case SIOCGIFNETMASK:    /* Get the netmask for the interface */
 998                 sin->sin_addr.s_addr = ifa->ifa_mask;
 999                 goto rarok;
1000
1001         case SIOCSIFFLAGS:
1002                 if (colon) {
1003                         ret = -EADDRNOTAVAIL;
1004                         if (!ifa)
1005                                 break;
1006                         ret = 0;
1007                         if (!(ifr.ifr_flags & IFF_UP))
1008                                 inet_del_ifa(in_dev, ifap, 1);
1009                         break;
1010                 }
1011                 ret = dev_change_flags(dev, ifr.ifr_flags);
1012                 break;
1013
1014         case SIOCSIFADDR:       /* Set interface address (and family) */
1015                 ret = -EINVAL;
1016                 if (inet_abc_len(sin->sin_addr.s_addr) < 0)
1017                         break;
1018
1019                 if (!ifa) {
1020                         ret = -ENOBUFS;
1021                         ifa = inet_alloc_ifa();
1022                         if (!ifa)
1023                                 break;
1024                         INIT_HLIST_NODE(&ifa->hash);
1025                         if (colon)
1026                                 memcpy(ifa->ifa_label, ifr.ifr_name, IFNAMSIZ);
1027                         else
1028                                 memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
1029                 } else {
1030                         ret = 0;
1031                         if (ifa->ifa_local == sin->sin_addr.s_addr)
1032                                 break;
1033                         inet_del_ifa(in_dev, ifap, 0);
1034                         ifa->ifa_broadcast = 0;
1035                         ifa->ifa_scope = 0;
1036                 }
1037
1038                 ifa->ifa_address = ifa->ifa_local = sin->sin_addr.s_addr;
1039
1040                 if (!(dev->flags & IFF_POINTOPOINT)) {
1041                         ifa->ifa_prefixlen = inet_abc_len(ifa->ifa_address);
1042                         ifa->ifa_mask = inet_make_mask(ifa->ifa_prefixlen);
1043                         if ((dev->flags & IFF_BROADCAST) &&
1044                             ifa->ifa_prefixlen < 31)
1045                                 ifa->ifa_broadcast = ifa->ifa_address |
1046                                                      ~ifa->ifa_mask;
1047                 } else {
1048                         ifa->ifa_prefixlen = 32;
1049                         ifa->ifa_mask = inet_make_mask(32);
1050                 }
1051                 set_ifa_lifetime(ifa, INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
1052                 ret = inet_set_ifa(dev, ifa);
1053                 break;
1054
1055         case SIOCSIFBRDADDR:    /* Set the broadcast address */
1056                 ret = 0;
1057                 if (ifa->ifa_broadcast != sin->sin_addr.s_addr) {
1058                         inet_del_ifa(in_dev, ifap, 0);
1059                         ifa->ifa_broadcast = sin->sin_addr.s_addr;
1060                         inet_insert_ifa(ifa);
1061                 }
1062                 break;
1063
1064         case SIOCSIFDSTADDR:    /* Set the destination address */
1065                 ret = 0;
1066                 if (ifa->ifa_address == sin->sin_addr.s_addr)
1067                         break;
1068                 ret = -EINVAL;
1069                 if (inet_abc_len(sin->sin_addr.s_addr) < 0)
1070                         break;
1071                 ret = 0;
1072                 inet_del_ifa(in_dev, ifap, 0);
1073                 ifa->ifa_address = sin->sin_addr.s_addr;
1074                 inet_insert_ifa(ifa);
1075                 break;
1076
1077         case SIOCSIFNETMASK:    /* Set the netmask for the interface */
1078
1079                 /*
1080                  *      The mask we set must be legal.
1081                  */
1082                 ret = -EINVAL;
1083                 if (bad_mask(sin->sin_addr.s_addr, 0))
1084                         break;
1085                 ret = 0;
1086                 if (ifa->ifa_mask != sin->sin_addr.s_addr) {
1087                         __be32 old_mask = ifa->ifa_mask;
1088                         inet_del_ifa(in_dev, ifap, 0);
1089                         ifa->ifa_mask = sin->sin_addr.s_addr;
1090                         ifa->ifa_prefixlen = inet_mask_len(ifa->ifa_mask);
1091
1092                         /* See if current broadcast address matches
1093                          * with current netmask, then recalculate
1094                          * the broadcast address. Otherwise it's a
1095                          * funny address, so don't touch it since
1096                          * the user seems to know what (s)he's doing...
1097                          */
1098                         if ((dev->flags & IFF_BROADCAST) &&
1099                             (ifa->ifa_prefixlen < 31) &&
1100                             (ifa->ifa_broadcast ==
1101                              (ifa->ifa_local|~old_mask))) {
1102                                 ifa->ifa_broadcast = (ifa->ifa_local |
1103                                                       ~sin->sin_addr.s_addr);
1104                         }
1105                         inet_insert_ifa(ifa);
1106                 }
1107                 break;
1108         }
1109 done:
1110         rtnl_unlock();
1111 out:
1112         return ret;
1113 rarok:
1114         rtnl_unlock();
1115         ret = copy_to_user(arg, &ifr, sizeof(struct ifreq)) ? -EFAULT : 0;
1116         goto out;
1117 }
1118
1119 static int inet_gifconf(struct net_device *dev, char __user *buf, int len)
1120 {
1121         struct in_device *in_dev = __in_dev_get_rtnl(dev);
1122         struct in_ifaddr *ifa;
1123         struct ifreq ifr;
1124         int done = 0;
1125
1126         if (!in_dev)
1127                 goto out;
1128
1129         for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
1130                 if (!buf) {
1131                         done += sizeof(ifr);
1132                         continue;
1133                 }
1134                 if (len < (int) sizeof(ifr))
1135                         break;
1136                 memset(&ifr, 0, sizeof(struct ifreq));
1137                 strcpy(ifr.ifr_name, ifa->ifa_label);
1138
1139                 (*(struct sockaddr_in *)&ifr.ifr_addr).sin_family = AF_INET;
1140                 (*(struct sockaddr_in *)&ifr.ifr_addr).sin_addr.s_addr =
1141                                                                 ifa->ifa_local;
1142
1143                 if (copy_to_user(buf, &ifr, sizeof(struct ifreq))) {
1144                         done = -EFAULT;
1145                         break;
1146                 }
1147                 buf  += sizeof(struct ifreq);
1148                 len  -= sizeof(struct ifreq);
1149                 done += sizeof(struct ifreq);
1150         }
1151 out:
1152         return done;
1153 }
1154
1155 __be32 inet_select_addr(const struct net_device *dev, __be32 dst, int scope)
1156 {
1157         __be32 addr = 0;
1158         struct in_device *in_dev;
1159         struct net *net = dev_net(dev);
1160
1161         rcu_read_lock();
1162         in_dev = __in_dev_get_rcu(dev);
1163         if (!in_dev)
1164                 goto no_in_dev;
1165
1166         for_primary_ifa(in_dev) {
1167                 if (ifa->ifa_scope > scope)
1168                         continue;
1169                 if (!dst || inet_ifa_match(dst, ifa)) {
1170                         addr = ifa->ifa_local;
1171                         break;
1172                 }
1173                 if (!addr)
1174                         addr = ifa->ifa_local;
1175         } endfor_ifa(in_dev);
1176
1177         if (addr)
1178                 goto out_unlock;
1179 no_in_dev:
1180
1181         /* Not loopback addresses on loopback should be preferred
1182            in this case. It is importnat that lo is the first interface
1183            in dev_base list.
1184          */
1185         for_each_netdev_rcu(net, dev) {
1186                 in_dev = __in_dev_get_rcu(dev);
1187                 if (!in_dev)
1188                         continue;
1189
1190                 for_primary_ifa(in_dev) {
1191                         if (ifa->ifa_scope != RT_SCOPE_LINK &&
1192                             ifa->ifa_scope <= scope) {
1193                                 addr = ifa->ifa_local;
1194                                 goto out_unlock;
1195                         }
1196                 } endfor_ifa(in_dev);
1197         }
1198 out_unlock:
1199         rcu_read_unlock();
1200         return addr;
1201 }
1202 EXPORT_SYMBOL(inet_select_addr);
1203
1204 static __be32 confirm_addr_indev(struct in_device *in_dev, __be32 dst,
1205                               __be32 local, int scope)
1206 {
1207         int same = 0;
1208         __be32 addr = 0;
1209
1210         for_ifa(in_dev) {
1211                 if (!addr &&
1212                     (local == ifa->ifa_local || !local) &&
1213                     ifa->ifa_scope <= scope) {
1214                         addr = ifa->ifa_local;
1215                         if (same)
1216                                 break;
1217                 }
1218                 if (!same) {
1219                         same = (!local || inet_ifa_match(local, ifa)) &&
1220                                 (!dst || inet_ifa_match(dst, ifa));
1221                         if (same && addr) {
1222                                 if (local || !dst)
1223                                         break;
1224                                 /* Is the selected addr into dst subnet? */
1225                                 if (inet_ifa_match(addr, ifa))
1226                                         break;
1227                                 /* No, then can we use new local src? */
1228                                 if (ifa->ifa_scope <= scope) {
1229                                         addr = ifa->ifa_local;
1230                                         break;
1231                                 }
1232                                 /* search for large dst subnet for addr */
1233                                 same = 0;
1234                         }
1235                 }
1236         } endfor_ifa(in_dev);
1237
1238         return same ? addr : 0;
1239 }
1240
1241 /*
1242  * Confirm that local IP address exists using wildcards:
1243  * - in_dev: only on this interface, 0=any interface
1244  * - dst: only in the same subnet as dst, 0=any dst
1245  * - local: address, 0=autoselect the local address
1246  * - scope: maximum allowed scope value for the local address
1247  */
1248 __be32 inet_confirm_addr(struct in_device *in_dev,
1249                          __be32 dst, __be32 local, int scope)
1250 {
1251         __be32 addr = 0;
1252         struct net_device *dev;
1253         struct net *net;
1254
1255         if (scope != RT_SCOPE_LINK)
1256                 return confirm_addr_indev(in_dev, dst, local, scope);
1257
1258         net = dev_net(in_dev->dev);
1259         rcu_read_lock();
1260         for_each_netdev_rcu(net, dev) {
1261                 in_dev = __in_dev_get_rcu(dev);
1262                 if (in_dev) {
1263                         addr = confirm_addr_indev(in_dev, dst, local, scope);
1264                         if (addr)
1265                                 break;
1266                 }
1267         }
1268         rcu_read_unlock();
1269
1270         return addr;
1271 }
1272 EXPORT_SYMBOL(inet_confirm_addr);
1273
1274 /*
1275  *      Device notifier
1276  */
1277
1278 int register_inetaddr_notifier(struct notifier_block *nb)
1279 {
1280         return blocking_notifier_chain_register(&inetaddr_chain, nb);
1281 }
1282 EXPORT_SYMBOL(register_inetaddr_notifier);
1283
1284 int unregister_inetaddr_notifier(struct notifier_block *nb)
1285 {
1286         return blocking_notifier_chain_unregister(&inetaddr_chain, nb);
1287 }
1288 EXPORT_SYMBOL(unregister_inetaddr_notifier);
1289
1290 /* Rename ifa_labels for a device name change. Make some effort to preserve
1291  * existing alias numbering and to create unique labels if possible.
1292 */
1293 static void inetdev_changename(struct net_device *dev, struct in_device *in_dev)
1294 {
1295         struct in_ifaddr *ifa;
1296         int named = 0;
1297
1298         for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
1299                 char old[IFNAMSIZ], *dot;
1300
1301                 memcpy(old, ifa->ifa_label, IFNAMSIZ);
1302                 memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
1303                 if (named++ == 0)
1304                         goto skip;
1305                 dot = strchr(old, ':');
1306                 if (dot == NULL) {
1307                         sprintf(old, ":%d", named);
1308                         dot = old;
1309                 }
1310                 if (strlen(dot) + strlen(dev->name) < IFNAMSIZ)
1311                         strcat(ifa->ifa_label, dot);
1312                 else
1313                         strcpy(ifa->ifa_label + (IFNAMSIZ - strlen(dot) - 1), dot);
1314 skip:
1315                 rtmsg_ifa(RTM_NEWADDR, ifa, NULL, 0);
1316         }
1317 }
1318
1319 static bool inetdev_valid_mtu(unsigned int mtu)
1320 {
1321         return mtu >= 68;
1322 }
1323
1324 static void inetdev_send_gratuitous_arp(struct net_device *dev,
1325                                         struct in_device *in_dev)
1326
1327 {
1328         struct in_ifaddr *ifa;
1329
1330         for (ifa = in_dev->ifa_list; ifa;
1331              ifa = ifa->ifa_next) {
1332                 arp_send(ARPOP_REQUEST, ETH_P_ARP,
1333                          ifa->ifa_local, dev,
1334                          ifa->ifa_local, NULL,
1335                          dev->dev_addr, NULL);
1336         }
1337 }
1338
1339 /* Called only under RTNL semaphore */
1340
1341 static int inetdev_event(struct notifier_block *this, unsigned long event,
1342                          void *ptr)
1343 {
1344         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1345         struct in_device *in_dev = __in_dev_get_rtnl(dev);
1346
1347         ASSERT_RTNL();
1348
1349         if (!in_dev) {
1350                 if (event == NETDEV_REGISTER) {
1351                         in_dev = inetdev_init(dev);
1352                         if (!in_dev)
1353                                 return notifier_from_errno(-ENOMEM);
1354                         if (dev->flags & IFF_LOOPBACK) {
1355                                 IN_DEV_CONF_SET(in_dev, NOXFRM, 1);
1356                                 IN_DEV_CONF_SET(in_dev, NOPOLICY, 1);
1357                         }
1358                 } else if (event == NETDEV_CHANGEMTU) {
1359                         /* Re-enabling IP */
1360                         if (inetdev_valid_mtu(dev->mtu))
1361                                 in_dev = inetdev_init(dev);
1362                 }
1363                 goto out;
1364         }
1365
1366         switch (event) {
1367         case NETDEV_REGISTER:
1368                 pr_debug("%s: bug\n", __func__);
1369                 RCU_INIT_POINTER(dev->ip_ptr, NULL);
1370                 break;
1371         case NETDEV_UP:
1372                 if (!inetdev_valid_mtu(dev->mtu))
1373                         break;
1374                 if (dev->flags & IFF_LOOPBACK) {
1375                         struct in_ifaddr *ifa = inet_alloc_ifa();
1376
1377                         if (ifa) {
1378                                 INIT_HLIST_NODE(&ifa->hash);
1379                                 ifa->ifa_local =
1380                                   ifa->ifa_address = htonl(INADDR_LOOPBACK);
1381                                 ifa->ifa_prefixlen = 8;
1382                                 ifa->ifa_mask = inet_make_mask(8);
1383                                 in_dev_hold(in_dev);
1384                                 ifa->ifa_dev = in_dev;
1385                                 ifa->ifa_scope = RT_SCOPE_HOST;
1386                                 memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
1387                                 set_ifa_lifetime(ifa, INFINITY_LIFE_TIME,
1388                                                  INFINITY_LIFE_TIME);
1389                                 inet_insert_ifa(ifa);
1390                         }
1391                 }
1392                 ip_mc_up(in_dev);
1393                 /* fall through */
1394         case NETDEV_CHANGEADDR:
1395                 if (!IN_DEV_ARP_NOTIFY(in_dev))
1396                         break;
1397                 /* fall through */
1398         case NETDEV_NOTIFY_PEERS:
1399                 /* Send gratuitous ARP to notify of link change */
1400                 inetdev_send_gratuitous_arp(dev, in_dev);
1401                 break;
1402         case NETDEV_DOWN:
1403                 ip_mc_down(in_dev);
1404                 break;
1405         case NETDEV_PRE_TYPE_CHANGE:
1406                 ip_mc_unmap(in_dev);
1407                 break;
1408         case NETDEV_POST_TYPE_CHANGE:
1409                 ip_mc_remap(in_dev);
1410                 break;
1411         case NETDEV_CHANGEMTU:
1412                 if (inetdev_valid_mtu(dev->mtu))
1413                         break;
1414                 /* disable IP when MTU is not enough */
1415         case NETDEV_UNREGISTER:
1416                 inetdev_destroy(in_dev);
1417                 break;
1418         case NETDEV_CHANGENAME:
1419                 /* Do not notify about label change, this event is
1420                  * not interesting to applications using netlink.
1421                  */
1422                 inetdev_changename(dev, in_dev);
1423
1424                 devinet_sysctl_unregister(in_dev);
1425                 devinet_sysctl_register(in_dev);
1426                 break;
1427         }
1428 out:
1429         return NOTIFY_DONE;
1430 }
1431
1432 static struct notifier_block ip_netdev_notifier = {
1433         .notifier_call = inetdev_event,
1434 };
1435
1436 static size_t inet_nlmsg_size(void)
1437 {
1438         return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
1439                + nla_total_size(4) /* IFA_ADDRESS */
1440                + nla_total_size(4) /* IFA_LOCAL */
1441                + nla_total_size(4) /* IFA_BROADCAST */
1442                + nla_total_size(IFNAMSIZ) /* IFA_LABEL */
1443                + nla_total_size(4);  /* IFA_FLAGS */
1444 }
1445
1446 static inline u32 cstamp_delta(unsigned long cstamp)
1447 {
1448         return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
1449 }
1450
1451 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
1452                          unsigned long tstamp, u32 preferred, u32 valid)
1453 {
1454         struct ifa_cacheinfo ci;
1455
1456         ci.cstamp = cstamp_delta(cstamp);
1457         ci.tstamp = cstamp_delta(tstamp);
1458         ci.ifa_prefered = preferred;
1459         ci.ifa_valid = valid;
1460
1461         return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
1462 }
1463
1464 static int inet_fill_ifaddr(struct sk_buff *skb, struct in_ifaddr *ifa,
1465                             u32 portid, u32 seq, int event, unsigned int flags)
1466 {
1467         struct ifaddrmsg *ifm;
1468         struct nlmsghdr  *nlh;
1469         u32 preferred, valid;
1470
1471         nlh = nlmsg_put(skb, portid, seq, event, sizeof(*ifm), flags);
1472         if (nlh == NULL)
1473                 return -EMSGSIZE;
1474
1475         ifm = nlmsg_data(nlh);
1476         ifm->ifa_family = AF_INET;
1477         ifm->ifa_prefixlen = ifa->ifa_prefixlen;
1478         ifm->ifa_flags = ifa->ifa_flags;
1479         ifm->ifa_scope = ifa->ifa_scope;
1480         ifm->ifa_index = ifa->ifa_dev->dev->ifindex;
1481
1482         if (!(ifm->ifa_flags & IFA_F_PERMANENT)) {
1483                 preferred = ifa->ifa_preferred_lft;
1484                 valid = ifa->ifa_valid_lft;
1485                 if (preferred != INFINITY_LIFE_TIME) {
1486                         long tval = (jiffies - ifa->ifa_tstamp) / HZ;
1487
1488                         if (preferred > tval)
1489                                 preferred -= tval;
1490                         else
1491                                 preferred = 0;
1492                         if (valid != INFINITY_LIFE_TIME) {
1493                                 if (valid > tval)
1494                                         valid -= tval;
1495                                 else
1496                                         valid = 0;
1497                         }
1498                 }
1499         } else {
1500                 preferred = INFINITY_LIFE_TIME;
1501                 valid = INFINITY_LIFE_TIME;
1502         }
1503         if ((ifa->ifa_address &&
1504              nla_put_be32(skb, IFA_ADDRESS, ifa->ifa_address)) ||
1505             (ifa->ifa_local &&
1506              nla_put_be32(skb, IFA_LOCAL, ifa->ifa_local)) ||
1507             (ifa->ifa_broadcast &&
1508              nla_put_be32(skb, IFA_BROADCAST, ifa->ifa_broadcast)) ||
1509             (ifa->ifa_label[0] &&
1510              nla_put_string(skb, IFA_LABEL, ifa->ifa_label)) ||
1511             nla_put_u32(skb, IFA_FLAGS, ifa->ifa_flags) ||
1512             put_cacheinfo(skb, ifa->ifa_cstamp, ifa->ifa_tstamp,
1513                           preferred, valid))
1514                 goto nla_put_failure;
1515
1516         return nlmsg_end(skb, nlh);
1517
1518 nla_put_failure:
1519         nlmsg_cancel(skb, nlh);
1520         return -EMSGSIZE;
1521 }
1522
1523 static int inet_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
1524 {
1525         struct net *net = sock_net(skb->sk);
1526         int h, s_h;
1527         int idx, s_idx;
1528         int ip_idx, s_ip_idx;
1529         struct net_device *dev;
1530         struct in_device *in_dev;
1531         struct in_ifaddr *ifa;
1532         struct hlist_head *head;
1533
1534         s_h = cb->args[0];
1535         s_idx = idx = cb->args[1];
1536         s_ip_idx = ip_idx = cb->args[2];
1537
1538         for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
1539                 idx = 0;
1540                 head = &net->dev_index_head[h];
1541                 rcu_read_lock();
1542                 cb->seq = atomic_read(&net->ipv4.dev_addr_genid) ^
1543                           net->dev_base_seq;
1544                 hlist_for_each_entry_rcu(dev, head, index_hlist) {
1545                         if (idx < s_idx)
1546                                 goto cont;
1547                         if (h > s_h || idx > s_idx)
1548                                 s_ip_idx = 0;
1549                         in_dev = __in_dev_get_rcu(dev);
1550                         if (!in_dev)
1551                                 goto cont;
1552
1553                         for (ifa = in_dev->ifa_list, ip_idx = 0; ifa;
1554                              ifa = ifa->ifa_next, ip_idx++) {
1555                                 if (ip_idx < s_ip_idx)
1556                                         continue;
1557                                 if (inet_fill_ifaddr(skb, ifa,
1558                                              NETLINK_CB(cb->skb).portid,
1559                                              cb->nlh->nlmsg_seq,
1560                                              RTM_NEWADDR, NLM_F_MULTI) <= 0) {
1561                                         rcu_read_unlock();
1562                                         goto done;
1563                                 }
1564                                 nl_dump_check_consistent(cb, nlmsg_hdr(skb));
1565                         }
1566 cont:
1567                         idx++;
1568                 }
1569                 rcu_read_unlock();
1570         }
1571
1572 done:
1573         cb->args[0] = h;
1574         cb->args[1] = idx;
1575         cb->args[2] = ip_idx;
1576
1577         return skb->len;
1578 }
1579
1580 static void rtmsg_ifa(int event, struct in_ifaddr *ifa, struct nlmsghdr *nlh,
1581                       u32 portid)
1582 {
1583         struct sk_buff *skb;
1584         u32 seq = nlh ? nlh->nlmsg_seq : 0;
1585         int err = -ENOBUFS;
1586         struct net *net;
1587
1588         net = dev_net(ifa->ifa_dev->dev);
1589         skb = nlmsg_new(inet_nlmsg_size(), GFP_KERNEL);
1590         if (skb == NULL)
1591                 goto errout;
1592
1593         err = inet_fill_ifaddr(skb, ifa, portid, seq, event, 0);
1594         if (err < 0) {
1595                 /* -EMSGSIZE implies BUG in inet_nlmsg_size() */
1596                 WARN_ON(err == -EMSGSIZE);
1597                 kfree_skb(skb);
1598                 goto errout;
1599         }
1600         rtnl_notify(skb, net, portid, RTNLGRP_IPV4_IFADDR, nlh, GFP_KERNEL);
1601         return;
1602 errout:
1603         if (err < 0)
1604                 rtnl_set_sk_err(net, RTNLGRP_IPV4_IFADDR, err);
1605 }
1606
1607 static size_t inet_get_link_af_size(const struct net_device *dev)
1608 {
1609         struct in_device *in_dev = rcu_dereference_rtnl(dev->ip_ptr);
1610
1611         if (!in_dev)
1612                 return 0;
1613
1614         return nla_total_size(IPV4_DEVCONF_MAX * 4); /* IFLA_INET_CONF */
1615 }
1616
1617 static int inet_fill_link_af(struct sk_buff *skb, const struct net_device *dev)
1618 {
1619         struct in_device *in_dev = rcu_dereference_rtnl(dev->ip_ptr);
1620         struct nlattr *nla;
1621         int i;
1622
1623         if (!in_dev)
1624                 return -ENODATA;
1625
1626         nla = nla_reserve(skb, IFLA_INET_CONF, IPV4_DEVCONF_MAX * 4);
1627         if (nla == NULL)
1628                 return -EMSGSIZE;
1629
1630         for (i = 0; i < IPV4_DEVCONF_MAX; i++)
1631                 ((u32 *) nla_data(nla))[i] = in_dev->cnf.data[i];
1632
1633         return 0;
1634 }
1635
1636 static const struct nla_policy inet_af_policy[IFLA_INET_MAX+1] = {
1637         [IFLA_INET_CONF]        = { .type = NLA_NESTED },
1638 };
1639
1640 static int inet_validate_link_af(const struct net_device *dev,
1641                                  const struct nlattr *nla)
1642 {
1643         struct nlattr *a, *tb[IFLA_INET_MAX+1];
1644         int err, rem;
1645
1646         if (dev && !__in_dev_get_rtnl(dev))
1647                 return -EAFNOSUPPORT;
1648
1649         err = nla_parse_nested(tb, IFLA_INET_MAX, nla, inet_af_policy);
1650         if (err < 0)
1651                 return err;
1652
1653         if (tb[IFLA_INET_CONF]) {
1654                 nla_for_each_nested(a, tb[IFLA_INET_CONF], rem) {
1655                         int cfgid = nla_type(a);
1656
1657                         if (nla_len(a) < 4)
1658                                 return -EINVAL;
1659
1660                         if (cfgid <= 0 || cfgid > IPV4_DEVCONF_MAX)
1661                                 return -EINVAL;
1662                 }
1663         }
1664
1665         return 0;
1666 }
1667
1668 static int inet_set_link_af(struct net_device *dev, const struct nlattr *nla)
1669 {
1670         struct in_device *in_dev = __in_dev_get_rtnl(dev);
1671         struct nlattr *a, *tb[IFLA_INET_MAX+1];
1672         int rem;
1673
1674         if (!in_dev)
1675                 return -EAFNOSUPPORT;
1676
1677         if (nla_parse_nested(tb, IFLA_INET_MAX, nla, NULL) < 0)
1678                 BUG();
1679
1680         if (tb[IFLA_INET_CONF]) {
1681                 nla_for_each_nested(a, tb[IFLA_INET_CONF], rem)
1682                         ipv4_devconf_set(in_dev, nla_type(a), nla_get_u32(a));
1683         }
1684
1685         return 0;
1686 }
1687
1688 static int inet_netconf_msgsize_devconf(int type)
1689 {
1690         int size = NLMSG_ALIGN(sizeof(struct netconfmsg))
1691                    + nla_total_size(4); /* NETCONFA_IFINDEX */
1692
1693         /* type -1 is used for ALL */
1694         if (type == -1 || type == NETCONFA_FORWARDING)
1695                 size += nla_total_size(4);
1696         if (type == -1 || type == NETCONFA_RP_FILTER)
1697                 size += nla_total_size(4);
1698         if (type == -1 || type == NETCONFA_MC_FORWARDING)
1699                 size += nla_total_size(4);
1700
1701         return size;
1702 }
1703
1704 static int inet_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
1705                                      struct ipv4_devconf *devconf, u32 portid,
1706                                      u32 seq, int event, unsigned int flags,
1707                                      int type)
1708 {
1709         struct nlmsghdr  *nlh;
1710         struct netconfmsg *ncm;
1711
1712         nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
1713                         flags);
1714         if (nlh == NULL)
1715                 return -EMSGSIZE;
1716
1717         ncm = nlmsg_data(nlh);
1718         ncm->ncm_family = AF_INET;
1719
1720         if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
1721                 goto nla_put_failure;
1722
1723         /* type -1 is used for ALL */
1724         if ((type == -1 || type == NETCONFA_FORWARDING) &&
1725             nla_put_s32(skb, NETCONFA_FORWARDING,
1726                         IPV4_DEVCONF(*devconf, FORWARDING)) < 0)
1727                 goto nla_put_failure;
1728         if ((type == -1 || type == NETCONFA_RP_FILTER) &&
1729             nla_put_s32(skb, NETCONFA_RP_FILTER,
1730                         IPV4_DEVCONF(*devconf, RP_FILTER)) < 0)
1731                 goto nla_put_failure;
1732         if ((type == -1 || type == NETCONFA_MC_FORWARDING) &&
1733             nla_put_s32(skb, NETCONFA_MC_FORWARDING,
1734                         IPV4_DEVCONF(*devconf, MC_FORWARDING)) < 0)
1735                 goto nla_put_failure;
1736
1737         return nlmsg_end(skb, nlh);
1738
1739 nla_put_failure:
1740         nlmsg_cancel(skb, nlh);
1741         return -EMSGSIZE;
1742 }
1743
1744 void inet_netconf_notify_devconf(struct net *net, int type, int ifindex,
1745                                  struct ipv4_devconf *devconf)
1746 {
1747         struct sk_buff *skb;
1748         int err = -ENOBUFS;
1749
1750         skb = nlmsg_new(inet_netconf_msgsize_devconf(type), GFP_ATOMIC);
1751         if (skb == NULL)
1752                 goto errout;
1753
1754         err = inet_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
1755                                         RTM_NEWNETCONF, 0, type);
1756         if (err < 0) {
1757                 /* -EMSGSIZE implies BUG in inet_netconf_msgsize_devconf() */
1758                 WARN_ON(err == -EMSGSIZE);
1759                 kfree_skb(skb);
1760                 goto errout;
1761         }
1762         rtnl_notify(skb, net, 0, RTNLGRP_IPV4_NETCONF, NULL, GFP_ATOMIC);
1763         return;
1764 errout:
1765         if (err < 0)
1766                 rtnl_set_sk_err(net, RTNLGRP_IPV4_NETCONF, err);
1767 }
1768
1769 static const struct nla_policy devconf_ipv4_policy[NETCONFA_MAX+1] = {
1770         [NETCONFA_IFINDEX]      = { .len = sizeof(int) },
1771         [NETCONFA_FORWARDING]   = { .len = sizeof(int) },
1772         [NETCONFA_RP_FILTER]    = { .len = sizeof(int) },
1773 };
1774
1775 static int inet_netconf_get_devconf(struct sk_buff *in_skb,
1776                                     struct nlmsghdr *nlh)
1777 {
1778         struct net *net = sock_net(in_skb->sk);
1779         struct nlattr *tb[NETCONFA_MAX+1];
1780         struct netconfmsg *ncm;
1781         struct sk_buff *skb;
1782         struct ipv4_devconf *devconf;
1783         struct in_device *in_dev;
1784         struct net_device *dev;
1785         int ifindex;
1786         int err;
1787
1788         err = nlmsg_parse(nlh, sizeof(*ncm), tb, NETCONFA_MAX,
1789                           devconf_ipv4_policy);
1790         if (err < 0)
1791                 goto errout;
1792
1793         err = EINVAL;
1794         if (!tb[NETCONFA_IFINDEX])
1795                 goto errout;
1796
1797         ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
1798         switch (ifindex) {
1799         case NETCONFA_IFINDEX_ALL:
1800                 devconf = net->ipv4.devconf_all;
1801                 break;
1802         case NETCONFA_IFINDEX_DEFAULT:
1803                 devconf = net->ipv4.devconf_dflt;
1804                 break;
1805         default:
1806                 dev = __dev_get_by_index(net, ifindex);
1807                 if (dev == NULL)
1808                         goto errout;
1809                 in_dev = __in_dev_get_rtnl(dev);
1810                 if (in_dev == NULL)
1811                         goto errout;
1812                 devconf = &in_dev->cnf;
1813                 break;
1814         }
1815
1816         err = -ENOBUFS;
1817         skb = nlmsg_new(inet_netconf_msgsize_devconf(-1), GFP_ATOMIC);
1818         if (skb == NULL)
1819                 goto errout;
1820
1821         err = inet_netconf_fill_devconf(skb, ifindex, devconf,
1822                                         NETLINK_CB(in_skb).portid,
1823                                         nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
1824                                         -1);
1825         if (err < 0) {
1826                 /* -EMSGSIZE implies BUG in inet_netconf_msgsize_devconf() */
1827                 WARN_ON(err == -EMSGSIZE);
1828                 kfree_skb(skb);
1829                 goto errout;
1830         }
1831         err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
1832 errout:
1833         return err;
1834 }
1835
1836 static int inet_netconf_dump_devconf(struct sk_buff *skb,
1837                                      struct netlink_callback *cb)
1838 {
1839         struct net *net = sock_net(skb->sk);
1840         int h, s_h;
1841         int idx, s_idx;
1842         struct net_device *dev;
1843         struct in_device *in_dev;
1844         struct hlist_head *head;
1845
1846         s_h = cb->args[0];
1847         s_idx = idx = cb->args[1];
1848
1849         for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
1850                 idx = 0;
1851                 head = &net->dev_index_head[h];
1852                 rcu_read_lock();
1853                 cb->seq = atomic_read(&net->ipv4.dev_addr_genid) ^
1854                           net->dev_base_seq;
1855                 hlist_for_each_entry_rcu(dev, head, index_hlist) {
1856                         if (idx < s_idx)
1857                                 goto cont;
1858                         in_dev = __in_dev_get_rcu(dev);
1859                         if (!in_dev)
1860                                 goto cont;
1861
1862                         if (inet_netconf_fill_devconf(skb, dev->ifindex,
1863                                                       &in_dev->cnf,
1864                                                       NETLINK_CB(cb->skb).portid,
1865                                                       cb->nlh->nlmsg_seq,
1866                                                       RTM_NEWNETCONF,
1867                                                       NLM_F_MULTI,
1868                                                       -1) <= 0) {
1869                                 rcu_read_unlock();
1870                                 goto done;
1871                         }
1872                         nl_dump_check_consistent(cb, nlmsg_hdr(skb));
1873 cont:
1874                         idx++;
1875                 }
1876                 rcu_read_unlock();
1877         }
1878         if (h == NETDEV_HASHENTRIES) {
1879                 if (inet_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
1880                                               net->ipv4.devconf_all,
1881                                               NETLINK_CB(cb->skb).portid,
1882                                               cb->nlh->nlmsg_seq,
1883                                               RTM_NEWNETCONF, NLM_F_MULTI,
1884                                               -1) <= 0)
1885                         goto done;
1886                 else
1887                         h++;
1888         }
1889         if (h == NETDEV_HASHENTRIES + 1) {
1890                 if (inet_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
1891                                               net->ipv4.devconf_dflt,
1892                                               NETLINK_CB(cb->skb).portid,
1893                                               cb->nlh->nlmsg_seq,
1894                                               RTM_NEWNETCONF, NLM_F_MULTI,
1895                                               -1) <= 0)
1896                         goto done;
1897                 else
1898                         h++;
1899         }
1900 done:
1901         cb->args[0] = h;
1902         cb->args[1] = idx;
1903
1904         return skb->len;
1905 }
1906
1907 #ifdef CONFIG_SYSCTL
1908
1909 static void devinet_copy_dflt_conf(struct net *net, int i)
1910 {
1911         struct net_device *dev;
1912
1913         rcu_read_lock();
1914         for_each_netdev_rcu(net, dev) {
1915                 struct in_device *in_dev;
1916
1917                 in_dev = __in_dev_get_rcu(dev);
1918                 if (in_dev && !test_bit(i, in_dev->cnf.state))
1919                         in_dev->cnf.data[i] = net->ipv4.devconf_dflt->data[i];
1920         }
1921         rcu_read_unlock();
1922 }
1923
1924 /* called with RTNL locked */
1925 static void inet_forward_change(struct net *net)
1926 {
1927         struct net_device *dev;
1928         int on = IPV4_DEVCONF_ALL(net, FORWARDING);
1929
1930         IPV4_DEVCONF_ALL(net, ACCEPT_REDIRECTS) = !on;
1931         IPV4_DEVCONF_DFLT(net, FORWARDING) = on;
1932         inet_netconf_notify_devconf(net, NETCONFA_FORWARDING,
1933                                     NETCONFA_IFINDEX_ALL,
1934                                     net->ipv4.devconf_all);
1935         inet_netconf_notify_devconf(net, NETCONFA_FORWARDING,
1936                                     NETCONFA_IFINDEX_DEFAULT,
1937                                     net->ipv4.devconf_dflt);
1938
1939         for_each_netdev(net, dev) {
1940                 struct in_device *in_dev;
1941                 if (on)
1942                         dev_disable_lro(dev);
1943                 rcu_read_lock();
1944                 in_dev = __in_dev_get_rcu(dev);
1945                 if (in_dev) {
1946                         IN_DEV_CONF_SET(in_dev, FORWARDING, on);
1947                         inet_netconf_notify_devconf(net, NETCONFA_FORWARDING,
1948                                                     dev->ifindex, &in_dev->cnf);
1949                 }
1950                 rcu_read_unlock();
1951         }
1952 }
1953
1954 static int devinet_conf_proc(struct ctl_table *ctl, int write,
1955                              void __user *buffer,
1956                              size_t *lenp, loff_t *ppos)
1957 {
1958         int old_value = *(int *)ctl->data;
1959         int ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
1960         int new_value = *(int *)ctl->data;
1961
1962         if (write) {
1963                 struct ipv4_devconf *cnf = ctl->extra1;
1964                 struct net *net = ctl->extra2;
1965                 int i = (int *)ctl->data - cnf->data;
1966
1967                 set_bit(i, cnf->state);
1968
1969                 if (cnf == net->ipv4.devconf_dflt)
1970                         devinet_copy_dflt_conf(net, i);
1971                 if (i == IPV4_DEVCONF_ACCEPT_LOCAL - 1 ||
1972                     i == IPV4_DEVCONF_ROUTE_LOCALNET - 1)
1973                         if ((new_value == 0) && (old_value != 0))
1974                                 rt_cache_flush(net);
1975                 if (i == IPV4_DEVCONF_RP_FILTER - 1 &&
1976                     new_value != old_value) {
1977                         int ifindex;
1978
1979                         if (cnf == net->ipv4.devconf_dflt)
1980                                 ifindex = NETCONFA_IFINDEX_DEFAULT;
1981                         else if (cnf == net->ipv4.devconf_all)
1982                                 ifindex = NETCONFA_IFINDEX_ALL;
1983                         else {
1984                                 struct in_device *idev =
1985                                         container_of(cnf, struct in_device,
1986                                                      cnf);
1987                                 ifindex = idev->dev->ifindex;
1988                         }
1989                         inet_netconf_notify_devconf(net, NETCONFA_RP_FILTER,
1990                                                     ifindex, cnf);
1991                 }
1992         }
1993
1994         return ret;
1995 }
1996
1997 static int devinet_sysctl_forward(struct ctl_table *ctl, int write,
1998                                   void __user *buffer,
1999                                   size_t *lenp, loff_t *ppos)
2000 {
2001         int *valp = ctl->data;
2002         int val = *valp;
2003         loff_t pos = *ppos;
2004         int ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
2005
2006         if (write && *valp != val) {
2007                 struct net *net = ctl->extra2;
2008
2009                 if (valp != &IPV4_DEVCONF_DFLT(net, FORWARDING)) {
2010                         if (!rtnl_trylock()) {
2011                                 /* Restore the original values before restarting */
2012                                 *valp = val;
2013                                 *ppos = pos;
2014                                 return restart_syscall();
2015                         }
2016                         if (valp == &IPV4_DEVCONF_ALL(net, FORWARDING)) {
2017                                 inet_forward_change(net);
2018                         } else {
2019                                 struct ipv4_devconf *cnf = ctl->extra1;
2020                                 struct in_device *idev =
2021                                         container_of(cnf, struct in_device, cnf);
2022                                 if (*valp)
2023                                         dev_disable_lro(idev->dev);
2024                                 inet_netconf_notify_devconf(net,
2025                                                             NETCONFA_FORWARDING,
2026                                                             idev->dev->ifindex,
2027                                                             cnf);
2028                         }
2029                         rtnl_unlock();
2030                         rt_cache_flush(net);
2031                 } else
2032                         inet_netconf_notify_devconf(net, NETCONFA_FORWARDING,
2033                                                     NETCONFA_IFINDEX_DEFAULT,
2034                                                     net->ipv4.devconf_dflt);
2035         }
2036
2037         return ret;
2038 }
2039
2040 static int ipv4_doint_and_flush(struct ctl_table *ctl, int write,
2041                                 void __user *buffer,
2042                                 size_t *lenp, loff_t *ppos)
2043 {
2044         int *valp = ctl->data;
2045         int val = *valp;
2046         int ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
2047         struct net *net = ctl->extra2;
2048
2049         if (write && *valp != val)
2050                 rt_cache_flush(net);
2051
2052         return ret;
2053 }
2054
2055 #define DEVINET_SYSCTL_ENTRY(attr, name, mval, proc) \
2056         { \
2057                 .procname       = name, \
2058                 .data           = ipv4_devconf.data + \
2059                                   IPV4_DEVCONF_ ## attr - 1, \
2060                 .maxlen         = sizeof(int), \
2061                 .mode           = mval, \
2062                 .proc_handler   = proc, \
2063                 .extra1         = &ipv4_devconf, \
2064         }
2065
2066 #define DEVINET_SYSCTL_RW_ENTRY(attr, name) \
2067         DEVINET_SYSCTL_ENTRY(attr, name, 0644, devinet_conf_proc)
2068
2069 #define DEVINET_SYSCTL_RO_ENTRY(attr, name) \
2070         DEVINET_SYSCTL_ENTRY(attr, name, 0444, devinet_conf_proc)
2071
2072 #define DEVINET_SYSCTL_COMPLEX_ENTRY(attr, name, proc) \
2073         DEVINET_SYSCTL_ENTRY(attr, name, 0644, proc)
2074
2075 #define DEVINET_SYSCTL_FLUSHING_ENTRY(attr, name) \
2076         DEVINET_SYSCTL_COMPLEX_ENTRY(attr, name, ipv4_doint_and_flush)
2077
2078 static struct devinet_sysctl_table {
2079         struct ctl_table_header *sysctl_header;
2080         struct ctl_table devinet_vars[__IPV4_DEVCONF_MAX];
2081 } devinet_sysctl = {
2082         .devinet_vars = {
2083                 DEVINET_SYSCTL_COMPLEX_ENTRY(FORWARDING, "forwarding",
2084                                              devinet_sysctl_forward),
2085                 DEVINET_SYSCTL_RO_ENTRY(MC_FORWARDING, "mc_forwarding"),
2086
2087                 DEVINET_SYSCTL_RW_ENTRY(ACCEPT_REDIRECTS, "accept_redirects"),
2088                 DEVINET_SYSCTL_RW_ENTRY(SECURE_REDIRECTS, "secure_redirects"),
2089                 DEVINET_SYSCTL_RW_ENTRY(SHARED_MEDIA, "shared_media"),
2090                 DEVINET_SYSCTL_RW_ENTRY(RP_FILTER, "rp_filter"),
2091                 DEVINET_SYSCTL_RW_ENTRY(SEND_REDIRECTS, "send_redirects"),
2092                 DEVINET_SYSCTL_RW_ENTRY(ACCEPT_SOURCE_ROUTE,
2093                                         "accept_source_route"),
2094                 DEVINET_SYSCTL_RW_ENTRY(ACCEPT_LOCAL, "accept_local"),
2095                 DEVINET_SYSCTL_RW_ENTRY(SRC_VMARK, "src_valid_mark"),
2096                 DEVINET_SYSCTL_RW_ENTRY(PROXY_ARP, "proxy_arp"),
2097                 DEVINET_SYSCTL_RW_ENTRY(MEDIUM_ID, "medium_id"),
2098                 DEVINET_SYSCTL_RW_ENTRY(BOOTP_RELAY, "bootp_relay"),
2099                 DEVINET_SYSCTL_RW_ENTRY(LOG_MARTIANS, "log_martians"),
2100                 DEVINET_SYSCTL_RW_ENTRY(TAG, "tag"),
2101                 DEVINET_SYSCTL_RW_ENTRY(ARPFILTER, "arp_filter"),
2102                 DEVINET_SYSCTL_RW_ENTRY(ARP_ANNOUNCE, "arp_announce"),
2103                 DEVINET_SYSCTL_RW_ENTRY(ARP_IGNORE, "arp_ignore"),
2104                 DEVINET_SYSCTL_RW_ENTRY(ARP_ACCEPT, "arp_accept"),
2105                 DEVINET_SYSCTL_RW_ENTRY(ARP_NOTIFY, "arp_notify"),
2106                 DEVINET_SYSCTL_RW_ENTRY(PROXY_ARP_PVLAN, "proxy_arp_pvlan"),
2107                 DEVINET_SYSCTL_RW_ENTRY(FORCE_IGMP_VERSION,
2108                                         "force_igmp_version"),
2109                 DEVINET_SYSCTL_RW_ENTRY(IGMPV2_UNSOLICITED_REPORT_INTERVAL,
2110                                         "igmpv2_unsolicited_report_interval"),
2111                 DEVINET_SYSCTL_RW_ENTRY(IGMPV3_UNSOLICITED_REPORT_INTERVAL,
2112                                         "igmpv3_unsolicited_report_interval"),
2113
2114                 DEVINET_SYSCTL_FLUSHING_ENTRY(NOXFRM, "disable_xfrm"),
2115                 DEVINET_SYSCTL_FLUSHING_ENTRY(NOPOLICY, "disable_policy"),
2116                 DEVINET_SYSCTL_FLUSHING_ENTRY(PROMOTE_SECONDARIES,
2117                                               "promote_secondaries"),
2118                 DEVINET_SYSCTL_FLUSHING_ENTRY(ROUTE_LOCALNET,
2119                                               "route_localnet"),
2120         },
2121 };
2122
2123 static int __devinet_sysctl_register(struct net *net, char *dev_name,
2124                                         struct ipv4_devconf *p)
2125 {
2126         int i;
2127         struct devinet_sysctl_table *t;
2128         char path[sizeof("net/ipv4/conf/") + IFNAMSIZ];
2129
2130         t = kmemdup(&devinet_sysctl, sizeof(*t), GFP_KERNEL);
2131         if (!t)
2132                 goto out;
2133
2134         for (i = 0; i < ARRAY_SIZE(t->devinet_vars) - 1; i++) {
2135                 t->devinet_vars[i].data += (char *)p - (char *)&ipv4_devconf;
2136                 t->devinet_vars[i].extra1 = p;
2137                 t->devinet_vars[i].extra2 = net;
2138         }
2139
2140         snprintf(path, sizeof(path), "net/ipv4/conf/%s", dev_name);
2141
2142         t->sysctl_header = register_net_sysctl(net, path, t->devinet_vars);
2143         if (!t->sysctl_header)
2144                 goto free;
2145
2146         p->sysctl = t;
2147         return 0;
2148
2149 free:
2150         kfree(t);
2151 out:
2152         return -ENOBUFS;
2153 }
2154
2155 static void __devinet_sysctl_unregister(struct ipv4_devconf *cnf)
2156 {
2157         struct devinet_sysctl_table *t = cnf->sysctl;
2158
2159         if (t == NULL)
2160                 return;
2161
2162         cnf->sysctl = NULL;
2163         unregister_net_sysctl_table(t->sysctl_header);
2164         kfree(t);
2165 }
2166
2167 static void devinet_sysctl_register(struct in_device *idev)
2168 {
2169         neigh_sysctl_register(idev->dev, idev->arp_parms, NULL);
2170         __devinet_sysctl_register(dev_net(idev->dev), idev->dev->name,
2171                                         &idev->cnf);
2172 }
2173
2174 static void devinet_sysctl_unregister(struct in_device *idev)
2175 {
2176         __devinet_sysctl_unregister(&idev->cnf);
2177         neigh_sysctl_unregister(idev->arp_parms);
2178 }
2179
2180 static struct ctl_table ctl_forward_entry[] = {
2181         {
2182                 .procname       = "ip_forward",
2183                 .data           = &ipv4_devconf.data[
2184                                         IPV4_DEVCONF_FORWARDING - 1],
2185                 .maxlen         = sizeof(int),
2186                 .mode           = 0644,
2187                 .proc_handler   = devinet_sysctl_forward,
2188                 .extra1         = &ipv4_devconf,
2189                 .extra2         = &init_net,
2190         },
2191         { },
2192 };
2193 #endif
2194
2195 static __net_init int devinet_init_net(struct net *net)
2196 {
2197         int err;
2198         struct ipv4_devconf *all, *dflt;
2199 #ifdef CONFIG_SYSCTL
2200         struct ctl_table *tbl = ctl_forward_entry;
2201         struct ctl_table_header *forw_hdr;
2202 #endif
2203
2204         err = -ENOMEM;
2205         all = &ipv4_devconf;
2206         dflt = &ipv4_devconf_dflt;
2207
2208         if (!net_eq(net, &init_net)) {
2209                 all = kmemdup(all, sizeof(ipv4_devconf), GFP_KERNEL);
2210                 if (all == NULL)
2211                         goto err_alloc_all;
2212
2213                 dflt = kmemdup(dflt, sizeof(ipv4_devconf_dflt), GFP_KERNEL);
2214                 if (dflt == NULL)
2215                         goto err_alloc_dflt;
2216
2217 #ifdef CONFIG_SYSCTL
2218                 tbl = kmemdup(tbl, sizeof(ctl_forward_entry), GFP_KERNEL);
2219                 if (tbl == NULL)
2220                         goto err_alloc_ctl;
2221
2222                 tbl[0].data = &all->data[IPV4_DEVCONF_FORWARDING - 1];
2223                 tbl[0].extra1 = all;
2224                 tbl[0].extra2 = net;
2225 #endif
2226         }
2227
2228 #ifdef CONFIG_SYSCTL
2229         err = __devinet_sysctl_register(net, "all", all);
2230         if (err < 0)
2231                 goto err_reg_all;
2232
2233         err = __devinet_sysctl_register(net, "default", dflt);
2234         if (err < 0)
2235                 goto err_reg_dflt;
2236
2237         err = -ENOMEM;
2238         forw_hdr = register_net_sysctl(net, "net/ipv4", tbl);
2239         if (forw_hdr == NULL)
2240                 goto err_reg_ctl;
2241         net->ipv4.forw_hdr = forw_hdr;
2242 #endif
2243
2244         net->ipv4.devconf_all = all;
2245         net->ipv4.devconf_dflt = dflt;
2246         return 0;
2247
2248 #ifdef CONFIG_SYSCTL
2249 err_reg_ctl:
2250         __devinet_sysctl_unregister(dflt);
2251 err_reg_dflt:
2252         __devinet_sysctl_unregister(all);
2253 err_reg_all:
2254         if (tbl != ctl_forward_entry)
2255                 kfree(tbl);
2256 err_alloc_ctl:
2257 #endif
2258         if (dflt != &ipv4_devconf_dflt)
2259                 kfree(dflt);
2260 err_alloc_dflt:
2261         if (all != &ipv4_devconf)
2262                 kfree(all);
2263 err_alloc_all:
2264         return err;
2265 }
2266
2267 static __net_exit void devinet_exit_net(struct net *net)
2268 {
2269 #ifdef CONFIG_SYSCTL
2270         struct ctl_table *tbl;
2271
2272         tbl = net->ipv4.forw_hdr->ctl_table_arg;
2273         unregister_net_sysctl_table(net->ipv4.forw_hdr);
2274         __devinet_sysctl_unregister(net->ipv4.devconf_dflt);
2275         __devinet_sysctl_unregister(net->ipv4.devconf_all);
2276         kfree(tbl);
2277 #endif
2278         kfree(net->ipv4.devconf_dflt);
2279         kfree(net->ipv4.devconf_all);
2280 }
2281
2282 static __net_initdata struct pernet_operations devinet_ops = {
2283         .init = devinet_init_net,
2284         .exit = devinet_exit_net,
2285 };
2286
2287 static struct rtnl_af_ops inet_af_ops = {
2288         .family           = AF_INET,
2289         .fill_link_af     = inet_fill_link_af,
2290         .get_link_af_size = inet_get_link_af_size,
2291         .validate_link_af = inet_validate_link_af,
2292         .set_link_af      = inet_set_link_af,
2293 };
2294
2295 void __init devinet_init(void)
2296 {
2297         int i;
2298
2299         for (i = 0; i < IN4_ADDR_HSIZE; i++)
2300                 INIT_HLIST_HEAD(&inet_addr_lst[i]);
2301
2302         register_pernet_subsys(&devinet_ops);
2303
2304         register_gifconf(PF_INET, inet_gifconf);
2305         register_netdevice_notifier(&ip_netdev_notifier);
2306
2307         schedule_delayed_work(&check_lifetime_work, 0);
2308
2309         rtnl_af_register(&inet_af_ops);
2310
2311         rtnl_register(PF_INET, RTM_NEWADDR, inet_rtm_newaddr, NULL, NULL);
2312         rtnl_register(PF_INET, RTM_DELADDR, inet_rtm_deladdr, NULL, NULL);
2313         rtnl_register(PF_INET, RTM_GETADDR, NULL, inet_dump_ifaddr, NULL);
2314         rtnl_register(PF_INET, RTM_GETNETCONF, inet_netconf_get_devconf,
2315                       inet_netconf_dump_devconf, NULL);
2316 }
2317