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   1 /*
   2  *      NET3    IP device support routines.
   3  *
   4  *      Version: $Id: devinet.c,v 1.44 2001/10/31 21:55:54 davem Exp $
   5  *
   6  *              This program is free software; you can redistribute it and/or
   7  *              modify it under the terms of the GNU General Public License
   8  *              as published by the Free Software Foundation; either version
   9  *              2 of the License, or (at your option) any later version.
  10  *
  11  *      Derived from the IP parts of dev.c 1.0.19
  12  *              Authors:        Ross Biro
  13  *                              Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
  14  *                              Mark Evans, <evansmp@uhura.aston.ac.uk>
  15  *
  16  *      Additional Authors:
  17  *              Alan Cox, <gw4pts@gw4pts.ampr.org>
  18  *              Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
  19  *
  20  *      Changes:
  21  *              Alexey Kuznetsov:       pa_* fields are replaced with ifaddr
  22  *                                      lists.
  23  *              Cyrus Durgin:           updated for kmod
  24  *              Matthias Andree:        in devinet_ioctl, compare label and
  25  *                                      address (4.4BSD alias style support),
  26  *                                      fall back to comparing just the label
  27  *                                      if no match found.
  28  */
  29
  30
  31 #include <asm/uaccess.h>
  32 #include <asm/system.h>
  33 #include <linux/bitops.h>
  34 #include <linux/capability.h>
  35 #include <linux/module.h>
  36 #include <linux/types.h>
  37 #include <linux/kernel.h>
  38 #include <linux/string.h>
  39 #include <linux/mm.h>
  40 #include <linux/socket.h>
  41 #include <linux/sockios.h>
  42 #include <linux/in.h>
  43 #include <linux/errno.h>
  44 #include <linux/interrupt.h>
  45 #include <linux/if_addr.h>
  46 #include <linux/if_ether.h>
  47 #include <linux/inet.h>
  48 #include <linux/netdevice.h>
  49 #include <linux/etherdevice.h>
  50 #include <linux/skbuff.h>
  51 #include <linux/init.h>
  52 #include <linux/notifier.h>
  53 #include <linux/inetdevice.h>
  54 #include <linux/igmp.h>
  55 #ifdef CONFIG_SYSCTL
  56 #include <linux/sysctl.h>
  57 #endif
  58 #include <linux/kmod.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
  67 struct ipv4_devconf ipv4_devconf = {
  68         .data = {
  69                 [NET_IPV4_CONF_ACCEPT_REDIRECTS - 1] = 1,
  70                 [NET_IPV4_CONF_SEND_REDIRECTS - 1] = 1,
  71                 [NET_IPV4_CONF_SECURE_REDIRECTS - 1] = 1,
  72                 [NET_IPV4_CONF_SHARED_MEDIA - 1] = 1,
  73         },
  74 };
  75
  76 static struct ipv4_devconf ipv4_devconf_dflt = {
  77         .data = {
  78                 [NET_IPV4_CONF_ACCEPT_REDIRECTS - 1] = 1,
  79                 [NET_IPV4_CONF_SEND_REDIRECTS - 1] = 1,
  80                 [NET_IPV4_CONF_SECURE_REDIRECTS - 1] = 1,
  81                 [NET_IPV4_CONF_SHARED_MEDIA - 1] = 1,
  82                 [NET_IPV4_CONF_ACCEPT_SOURCE_ROUTE - 1] = 1,
  83         },
  84 };
  85
  86 #define IPV4_DEVCONF_DFLT(net, attr) \
  87         IPV4_DEVCONF((*net->ipv4.devconf_dflt), attr)
  88
  89 static const struct nla_policy ifa_ipv4_policy[IFA_MAX+1] = {
  90         [IFA_LOCAL]             = { .type = NLA_U32 },
  91         [IFA_ADDRESS]           = { .type = NLA_U32 },
  92         [IFA_BROADCAST]         = { .type = NLA_U32 },
  93         [IFA_ANYCAST]           = { .type = NLA_U32 },
  94         [IFA_LABEL]             = { .type = NLA_STRING, .len = IFNAMSIZ - 1 },
  95 };
  96
  97 static void rtmsg_ifa(int event, struct in_ifaddr *, struct nlmsghdr *, u32);
  98
  99 static BLOCKING_NOTIFIER_HEAD(inetaddr_chain);
 100 static void inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap,
 101                          int destroy);
 102 #ifdef CONFIG_SYSCTL
 103 static void devinet_sysctl_register(struct in_device *idev);
 104 static void devinet_sysctl_unregister(struct in_device *idev);
 105 #else
 106 static inline void devinet_sysctl_register(struct in_device *idev)
 107 {
 108 }
 109 static inline void devinet_sysctl_unregister(struct in_device *idev)
 110 {
 111 }
 112 #endif
 113
 114 /* Locks all the inet devices. */
 115
 116 static struct in_ifaddr *inet_alloc_ifa(void)
 117 {
 118         struct in_ifaddr *ifa = kzalloc(sizeof(*ifa), GFP_KERNEL);
 119
 120         if (ifa) {
 121                 INIT_RCU_HEAD(&ifa->rcu_head);
 122         }
 123
 124         return ifa;
 125 }
 126
 127 static void inet_rcu_free_ifa(struct rcu_head *head)
 128 {
 129         struct in_ifaddr *ifa = container_of(head, struct in_ifaddr, rcu_head);
 130         if (ifa->ifa_dev)
 131                 in_dev_put(ifa->ifa_dev);
 132         kfree(ifa);
 133 }
 134
 135 static inline void inet_free_ifa(struct in_ifaddr *ifa)
 136 {
 137         call_rcu(&ifa->rcu_head, inet_rcu_free_ifa);
 138 }
 139
 140 void in_dev_finish_destroy(struct in_device *idev)
 141 {
 142         struct net_device *dev = idev->dev;
 143
 144         BUG_TRAP(!idev->ifa_list);
 145         BUG_TRAP(!idev->mc_list);
 146 #ifdef NET_REFCNT_DEBUG
 147         printk(KERN_DEBUG "in_dev_finish_destroy: %p=%s\n",
 148                idev, dev ? dev->name : "NIL");
 149 #endif
 150         dev_put(dev);
 151         if (!idev->dead)
 152                 printk("Freeing alive in_device %p\n", idev);
 153         else {
 154                 kfree(idev);
 155         }
 156 }
 157
 158 static struct in_device *inetdev_init(struct net_device *dev)
 159 {
 160         struct in_device *in_dev;
 161
 162         ASSERT_RTNL();
 163
 164         in_dev = kzalloc(sizeof(*in_dev), GFP_KERNEL);
 165         if (!in_dev)
 166                 goto out;
 167         INIT_RCU_HEAD(&in_dev->rcu_head);
 168         memcpy(&in_dev->cnf, dev->nd_net->ipv4.devconf_dflt,
 169                         sizeof(in_dev->cnf));
 170         in_dev->cnf.sysctl = NULL;
 171         in_dev->dev = dev;
 172         if ((in_dev->arp_parms = neigh_parms_alloc(dev, &arp_tbl)) == NULL)
 173                 goto out_kfree;
 174         /* Reference in_dev->dev */
 175         dev_hold(dev);
 176         /* Account for reference dev->ip_ptr (below) */
 177         in_dev_hold(in_dev);
 178
 179         devinet_sysctl_register(in_dev);
 180         ip_mc_init_dev(in_dev);
 181         if (dev->flags & IFF_UP)
 182                 ip_mc_up(in_dev);
 183
 184         /* we can receive as soon as ip_ptr is set -- do this last */
 185         rcu_assign_pointer(dev->ip_ptr, in_dev);
 186 out:
 187         return in_dev;
 188 out_kfree:
 189         kfree(in_dev);
 190         in_dev = NULL;
 191         goto out;
 192 }
 193
 194 static void in_dev_rcu_put(struct rcu_head *head)
 195 {
 196         struct in_device *idev = container_of(head, struct in_device, rcu_head);
 197         in_dev_put(idev);
 198 }
 199
 200 static void inetdev_destroy(struct in_device *in_dev)
 201 {
 202         struct in_ifaddr *ifa;
 203         struct net_device *dev;
 204
 205         ASSERT_RTNL();
 206
 207         dev = in_dev->dev;
 208
 209         in_dev->dead = 1;
 210
 211         ip_mc_destroy_dev(in_dev);
 212
 213         while ((ifa = in_dev->ifa_list) != NULL) {
 214                 inet_del_ifa(in_dev, &in_dev->ifa_list, 0);
 215                 inet_free_ifa(ifa);
 216         }
 217
 218         dev->ip_ptr = NULL;
 219
 220         devinet_sysctl_unregister(in_dev);
 221         neigh_parms_release(&arp_tbl, in_dev->arp_parms);
 222         arp_ifdown(dev);
 223
 224         call_rcu(&in_dev->rcu_head, in_dev_rcu_put);
 225 }
 226
 227 int inet_addr_onlink(struct in_device *in_dev, __be32 a, __be32 b)
 228 {
 229         rcu_read_lock();
 230         for_primary_ifa(in_dev) {
 231                 if (inet_ifa_match(a, ifa)) {
 232                         if (!b || inet_ifa_match(b, ifa)) {
 233                                 rcu_read_unlock();
 234                                 return 1;
 235                         }
 236                 }
 237         } endfor_ifa(in_dev);
 238         rcu_read_unlock();
 239         return 0;
 240 }
 241
 242 static void __inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap,
 243                          int destroy, struct nlmsghdr *nlh, u32 pid)
 244 {
 245         struct in_ifaddr *promote = NULL;
 246         struct in_ifaddr *ifa, *ifa1 = *ifap;
 247         struct in_ifaddr *last_prim = in_dev->ifa_list;
 248         struct in_ifaddr *prev_prom = NULL;
 249         int do_promote = IN_DEV_PROMOTE_SECONDARIES(in_dev);
 250
 251         ASSERT_RTNL();
 252
 253         /* 1. Deleting primary ifaddr forces deletion all secondaries
 254          * unless alias promotion is set
 255          **/
 256
 257         if (!(ifa1->ifa_flags & IFA_F_SECONDARY)) {
 258                 struct in_ifaddr **ifap1 = &ifa1->ifa_next;
 259
 260                 while ((ifa = *ifap1) != NULL) {
 261                         if (!(ifa->ifa_flags & IFA_F_SECONDARY) &&
 262                             ifa1->ifa_scope <= ifa->ifa_scope)
 263                                 last_prim = ifa;
 264
 265                         if (!(ifa->ifa_flags & IFA_F_SECONDARY) ||
 266                             ifa1->ifa_mask != ifa->ifa_mask ||
 267                             !inet_ifa_match(ifa1->ifa_address, ifa)) {
 268                                 ifap1 = &ifa->ifa_next;
 269                                 prev_prom = ifa;
 270                                 continue;
 271                         }
 272
 273                         if (!do_promote) {
 274                                 *ifap1 = ifa->ifa_next;
 275
 276                                 rtmsg_ifa(RTM_DELADDR, ifa, nlh, pid);
 277                                 blocking_notifier_call_chain(&inetaddr_chain,
 278                                                 NETDEV_DOWN, ifa);
 279                                 inet_free_ifa(ifa);
 280                         } else {
 281                                 promote = ifa;
 282                                 break;
 283                         }
 284                 }
 285         }
 286
 287         /* 2. Unlink it */
 288
 289         *ifap = ifa1->ifa_next;
 290
 291         /* 3. Announce address deletion */
 292
 293         /* Send message first, then call notifier.
 294            At first sight, FIB update triggered by notifier
 295            will refer to already deleted ifaddr, that could confuse
 296            netlink listeners. It is not true: look, gated sees
 297            that route deleted and if it still thinks that ifaddr
 298            is valid, it will try to restore deleted routes... Grr.
 299            So that, this order is correct.
 300          */
 301         rtmsg_ifa(RTM_DELADDR, ifa1, nlh, pid);
 302         blocking_notifier_call_chain(&inetaddr_chain, NETDEV_DOWN, ifa1);
 303
 304         if (promote) {
 305
 306                 if (prev_prom) {
 307                         prev_prom->ifa_next = promote->ifa_next;
 308                         promote->ifa_next = last_prim->ifa_next;
 309                         last_prim->ifa_next = promote;
 310                 }
 311
 312                 promote->ifa_flags &= ~IFA_F_SECONDARY;
 313                 rtmsg_ifa(RTM_NEWADDR, promote, nlh, pid);
 314                 blocking_notifier_call_chain(&inetaddr_chain,
 315                                 NETDEV_UP, promote);
 316                 for (ifa = promote->ifa_next; ifa; ifa = ifa->ifa_next) {
 317                         if (ifa1->ifa_mask != ifa->ifa_mask ||
 318                             !inet_ifa_match(ifa1->ifa_address, ifa))
 319                                         continue;
 320                         fib_add_ifaddr(ifa);
 321                 }
 322
 323         }
 324         if (destroy)
 325                 inet_free_ifa(ifa1);
 326 }
 327
 328 static void inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap,
 329                          int destroy)
 330 {
 331         __inet_del_ifa(in_dev, ifap, destroy, NULL, 0);
 332 }
 333
 334 static int __inet_insert_ifa(struct in_ifaddr *ifa, struct nlmsghdr *nlh,
 335                              u32 pid)
 336 {
 337         struct in_device *in_dev = ifa->ifa_dev;
 338         struct in_ifaddr *ifa1, **ifap, **last_primary;
 339
 340         ASSERT_RTNL();
 341
 342         if (!ifa->ifa_local) {
 343                 inet_free_ifa(ifa);
 344                 return 0;
 345         }
 346
 347         ifa->ifa_flags &= ~IFA_F_SECONDARY;
 348         last_primary = &in_dev->ifa_list;
 349
 350         for (ifap = &in_dev->ifa_list; (ifa1 = *ifap) != NULL;
 351              ifap = &ifa1->ifa_next) {
 352                 if (!(ifa1->ifa_flags & IFA_F_SECONDARY) &&
 353                     ifa->ifa_scope <= ifa1->ifa_scope)
 354                         last_primary = &ifa1->ifa_next;
 355                 if (ifa1->ifa_mask == ifa->ifa_mask &&
 356                     inet_ifa_match(ifa1->ifa_address, ifa)) {
 357                         if (ifa1->ifa_local == ifa->ifa_local) {
 358                                 inet_free_ifa(ifa);
 359                                 return -EEXIST;
 360                         }
 361                         if (ifa1->ifa_scope != ifa->ifa_scope) {
 362                                 inet_free_ifa(ifa);
 363                                 return -EINVAL;
 364                         }
 365                         ifa->ifa_flags |= IFA_F_SECONDARY;
 366                 }
 367         }
 368
 369         if (!(ifa->ifa_flags & IFA_F_SECONDARY)) {
 370                 net_srandom(ifa->ifa_local);
 371                 ifap = last_primary;
 372         }
 373
 374         ifa->ifa_next = *ifap;
 375         *ifap = ifa;
 376
 377         /* Send message first, then call notifier.
 378            Notifier will trigger FIB update, so that
 379            listeners of netlink will know about new ifaddr */
 380         rtmsg_ifa(RTM_NEWADDR, ifa, nlh, pid);
 381         blocking_notifier_call_chain(&inetaddr_chain, NETDEV_UP, ifa);
 382
 383         return 0;
 384 }
 385
 386 static int inet_insert_ifa(struct in_ifaddr *ifa)
 387 {
 388         return __inet_insert_ifa(ifa, NULL, 0);
 389 }
 390
 391 static int inet_set_ifa(struct net_device *dev, struct in_ifaddr *ifa)
 392 {
 393         struct in_device *in_dev = __in_dev_get_rtnl(dev);
 394
 395         ASSERT_RTNL();
 396
 397         if (!in_dev) {
 398                 inet_free_ifa(ifa);
 399                 return -ENOBUFS;
 400         }
 401         ipv4_devconf_setall(in_dev);
 402         if (ifa->ifa_dev != in_dev) {
 403                 BUG_TRAP(!ifa->ifa_dev);
 404                 in_dev_hold(in_dev);
 405                 ifa->ifa_dev = in_dev;
 406         }
 407         if (LOOPBACK(ifa->ifa_local))
 408                 ifa->ifa_scope = RT_SCOPE_HOST;
 409         return inet_insert_ifa(ifa);
 410 }
 411
 412 struct in_device *inetdev_by_index(int ifindex)
 413 {
 414         struct net_device *dev;
 415         struct in_device *in_dev = NULL;
 416         read_lock(&dev_base_lock);
 417         dev = __dev_get_by_index(&init_net, ifindex);
 418         if (dev)
 419                 in_dev = in_dev_get(dev);
 420         read_unlock(&dev_base_lock);
 421         return in_dev;
 422 }
 423
 424 /* Called only from RTNL semaphored context. No locks. */
 425
 426 struct in_ifaddr *inet_ifa_byprefix(struct in_device *in_dev, __be32 prefix,
 427                                     __be32 mask)
 428 {
 429         ASSERT_RTNL();
 430
 431         for_primary_ifa(in_dev) {
 432                 if (ifa->ifa_mask == mask && inet_ifa_match(prefix, ifa))
 433                         return ifa;
 434         } endfor_ifa(in_dev);
 435         return NULL;
 436 }
 437
 438 static int inet_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 439 {
 440         struct net *net = skb->sk->sk_net;
 441         struct nlattr *tb[IFA_MAX+1];
 442         struct in_device *in_dev;
 443         struct ifaddrmsg *ifm;
 444         struct in_ifaddr *ifa, **ifap;
 445         int err = -EINVAL;
 446
 447         ASSERT_RTNL();
 448
 449         if (net != &init_net)
 450                 return -EINVAL;
 451
 452         err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv4_policy);
 453         if (err < 0)
 454                 goto errout;
 455
 456         ifm = nlmsg_data(nlh);
 457         in_dev = inetdev_by_index(ifm->ifa_index);
 458         if (in_dev == NULL) {
 459                 err = -ENODEV;
 460                 goto errout;
 461         }
 462
 463         __in_dev_put(in_dev);
 464
 465         for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL;
 466              ifap = &ifa->ifa_next) {
 467                 if (tb[IFA_LOCAL] &&
 468                     ifa->ifa_local != nla_get_be32(tb[IFA_LOCAL]))
 469                         continue;
 470
 471                 if (tb[IFA_LABEL] && nla_strcmp(tb[IFA_LABEL], ifa->ifa_label))
 472                         continue;
 473
 474                 if (tb[IFA_ADDRESS] &&
 475                     (ifm->ifa_prefixlen != ifa->ifa_prefixlen ||
 476                     !inet_ifa_match(nla_get_be32(tb[IFA_ADDRESS]), ifa)))
 477                         continue;
 478
 479                 __inet_del_ifa(in_dev, ifap, 1, nlh, NETLINK_CB(skb).pid);
 480                 return 0;
 481         }
 482
 483         err = -EADDRNOTAVAIL;
 484 errout:
 485         return err;
 486 }
 487
 488 static struct in_ifaddr *rtm_to_ifaddr(struct nlmsghdr *nlh)
 489 {
 490         struct nlattr *tb[IFA_MAX+1];
 491         struct in_ifaddr *ifa;
 492         struct ifaddrmsg *ifm;
 493         struct net_device *dev;
 494         struct in_device *in_dev;
 495         int err = -EINVAL;
 496
 497         err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv4_policy);
 498         if (err < 0)
 499                 goto errout;
 500
 501         ifm = nlmsg_data(nlh);
 502         if (ifm->ifa_prefixlen > 32 || tb[IFA_LOCAL] == NULL) {
 503                 err = -EINVAL;
 504                 goto errout;
 505         }
 506
 507         dev = __dev_get_by_index(&init_net, ifm->ifa_index);
 508         if (dev == NULL) {
 509                 err = -ENODEV;
 510                 goto errout;
 511         }
 512
 513         in_dev = __in_dev_get_rtnl(dev);
 514         if (in_dev == NULL) {
 515                 err = -ENOBUFS;
 516                 goto errout;
 517         }
 518
 519         ifa = inet_alloc_ifa();
 520         if (ifa == NULL) {
 521                 /*
 522                  * A potential indev allocation can be left alive, it stays
 523                  * assigned to its device and is destroy with it.
 524                  */
 525                 err = -ENOBUFS;
 526                 goto errout;
 527         }
 528
 529         ipv4_devconf_setall(in_dev);
 530         in_dev_hold(in_dev);
 531
 532         if (tb[IFA_ADDRESS] == NULL)
 533                 tb[IFA_ADDRESS] = tb[IFA_LOCAL];
 534
 535         ifa->ifa_prefixlen = ifm->ifa_prefixlen;
 536         ifa->ifa_mask = inet_make_mask(ifm->ifa_prefixlen);
 537         ifa->ifa_flags = ifm->ifa_flags;
 538         ifa->ifa_scope = ifm->ifa_scope;
 539         ifa->ifa_dev = in_dev;
 540
 541         ifa->ifa_local = nla_get_be32(tb[IFA_LOCAL]);
 542         ifa->ifa_address = nla_get_be32(tb[IFA_ADDRESS]);
 543
 544         if (tb[IFA_BROADCAST])
 545                 ifa->ifa_broadcast = nla_get_be32(tb[IFA_BROADCAST]);
 546
 547         if (tb[IFA_ANYCAST])
 548                 ifa->ifa_anycast = nla_get_be32(tb[IFA_ANYCAST]);
 549
 550         if (tb[IFA_LABEL])
 551                 nla_strlcpy(ifa->ifa_label, tb[IFA_LABEL], IFNAMSIZ);
 552         else
 553                 memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
 554
 555         return ifa;
 556
 557 errout:
 558         return ERR_PTR(err);
 559 }
 560
 561 static int inet_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 562 {
 563         struct net *net = skb->sk->sk_net;
 564         struct in_ifaddr *ifa;
 565
 566         ASSERT_RTNL();
 567
 568         if (net != &init_net)
 569                 return -EINVAL;
 570
 571         ifa = rtm_to_ifaddr(nlh);
 572         if (IS_ERR(ifa))
 573                 return PTR_ERR(ifa);
 574
 575         return __inet_insert_ifa(ifa, nlh, NETLINK_CB(skb).pid);
 576 }
 577
 578 /*
 579  *      Determine a default network mask, based on the IP address.
 580  */
 581
 582 static __inline__ int inet_abc_len(__be32 addr)
 583 {
 584         int rc = -1;    /* Something else, probably a multicast. */
 585
 586         if (ZERONET(addr))
 587                 rc = 0;
 588         else {
 589                 __u32 haddr = ntohl(addr);
 590
 591                 if (IN_CLASSA(haddr))
 592                         rc = 8;
 593                 else if (IN_CLASSB(haddr))
 594                         rc = 16;
 595                 else if (IN_CLASSC(haddr))
 596                         rc = 24;
 597         }
 598
 599         return rc;
 600 }
 601
 602
 603 int devinet_ioctl(unsigned int cmd, void __user *arg)
 604 {
 605         struct ifreq ifr;
 606         struct sockaddr_in sin_orig;
 607         struct sockaddr_in *sin = (struct sockaddr_in *)&ifr.ifr_addr;
 608         struct in_device *in_dev;
 609         struct in_ifaddr **ifap = NULL;
 610         struct in_ifaddr *ifa = NULL;
 611         struct net_device *dev;
 612         char *colon;
 613         int ret = -EFAULT;
 614         int tryaddrmatch = 0;
 615
 616         /*
 617          *      Fetch the caller's info block into kernel space
 618          */
 619
 620         if (copy_from_user(&ifr, arg, sizeof(struct ifreq)))
 621                 goto out;
 622         ifr.ifr_name[IFNAMSIZ - 1] = 0;
 623
 624         /* save original address for comparison */
 625         memcpy(&sin_orig, sin, sizeof(*sin));
 626
 627         colon = strchr(ifr.ifr_name, ':');
 628         if (colon)
 629                 *colon = 0;
 630
 631 #ifdef CONFIG_KMOD
 632         dev_load(&init_net, ifr.ifr_name);
 633 #endif
 634
 635         switch (cmd) {
 636         case SIOCGIFADDR:       /* Get interface address */
 637         case SIOCGIFBRDADDR:    /* Get the broadcast address */
 638         case SIOCGIFDSTADDR:    /* Get the destination address */
 639         case SIOCGIFNETMASK:    /* Get the netmask for the interface */
 640                 /* Note that these ioctls will not sleep,
 641                    so that we do not impose a lock.
 642                    One day we will be forced to put shlock here (I mean SMP)
 643                  */
 644                 tryaddrmatch = (sin_orig.sin_family == AF_INET);
 645                 memset(sin, 0, sizeof(*sin));
 646                 sin->sin_family = AF_INET;
 647                 break;
 648
 649         case SIOCSIFFLAGS:
 650                 ret = -EACCES;
 651                 if (!capable(CAP_NET_ADMIN))
 652                         goto out;
 653                 break;
 654         case SIOCSIFADDR:       /* Set interface address (and family) */
 655         case SIOCSIFBRDADDR:    /* Set the broadcast address */
 656         case SIOCSIFDSTADDR:    /* Set the destination address */
 657         case SIOCSIFNETMASK:    /* Set the netmask for the interface */
 658                 ret = -EACCES;
 659                 if (!capable(CAP_NET_ADMIN))
 660                         goto out;
 661                 ret = -EINVAL;
 662                 if (sin->sin_family != AF_INET)
 663                         goto out;
 664                 break;
 665         default:
 666                 ret = -EINVAL;
 667                 goto out;
 668         }
 669
 670         rtnl_lock();
 671
 672         ret = -ENODEV;
 673         if ((dev = __dev_get_by_name(&init_net, ifr.ifr_name)) == NULL)
 674                 goto done;
 675
 676         if (colon)
 677                 *colon = ':';
 678
 679         if ((in_dev = __in_dev_get_rtnl(dev)) != NULL) {
 680                 if (tryaddrmatch) {
 681                         /* Matthias Andree */
 682                         /* compare label and address (4.4BSD style) */
 683                         /* note: we only do this for a limited set of ioctls
 684                            and only if the original address family was AF_INET.
 685                            This is checked above. */
 686                         for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL;
 687                              ifap = &ifa->ifa_next) {
 688                                 if (!strcmp(ifr.ifr_name, ifa->ifa_label) &&
 689                                     sin_orig.sin_addr.s_addr ==
 690                                                         ifa->ifa_address) {
 691                                         break; /* found */
 692                                 }
 693                         }
 694                 }
 695                 /* we didn't get a match, maybe the application is
 696                    4.3BSD-style and passed in junk so we fall back to
 697                    comparing just the label */
 698                 if (!ifa) {
 699                         for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL;
 700                              ifap = &ifa->ifa_next)
 701                                 if (!strcmp(ifr.ifr_name, ifa->ifa_label))
 702                                         break;
 703                 }
 704         }
 705
 706         ret = -EADDRNOTAVAIL;
 707         if (!ifa && cmd != SIOCSIFADDR && cmd != SIOCSIFFLAGS)
 708                 goto done;
 709
 710         switch (cmd) {
 711         case SIOCGIFADDR:       /* Get interface address */
 712                 sin->sin_addr.s_addr = ifa->ifa_local;
 713                 goto rarok;
 714
 715         case SIOCGIFBRDADDR:    /* Get the broadcast address */
 716                 sin->sin_addr.s_addr = ifa->ifa_broadcast;
 717                 goto rarok;
 718
 719         case SIOCGIFDSTADDR:    /* Get the destination address */
 720                 sin->sin_addr.s_addr = ifa->ifa_address;
 721                 goto rarok;
 722
 723         case SIOCGIFNETMASK:    /* Get the netmask for the interface */
 724                 sin->sin_addr.s_addr = ifa->ifa_mask;
 725                 goto rarok;
 726
 727         case SIOCSIFFLAGS:
 728                 if (colon) {
 729                         ret = -EADDRNOTAVAIL;
 730                         if (!ifa)
 731                                 break;
 732                         ret = 0;
 733                         if (!(ifr.ifr_flags & IFF_UP))
 734                                 inet_del_ifa(in_dev, ifap, 1);
 735                         break;
 736                 }
 737                 ret = dev_change_flags(dev, ifr.ifr_flags);
 738                 break;
 739
 740         case SIOCSIFADDR:       /* Set interface address (and family) */
 741                 ret = -EINVAL;
 742                 if (inet_abc_len(sin->sin_addr.s_addr) < 0)
 743                         break;
 744
 745                 if (!ifa) {
 746                         ret = -ENOBUFS;
 747                         if ((ifa = inet_alloc_ifa()) == NULL)
 748                                 break;
 749                         if (colon)
 750                                 memcpy(ifa->ifa_label, ifr.ifr_name, IFNAMSIZ);
 751                         else
 752                                 memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
 753                 } else {
 754                         ret = 0;
 755                         if (ifa->ifa_local == sin->sin_addr.s_addr)
 756                                 break;
 757                         inet_del_ifa(in_dev, ifap, 0);
 758                         ifa->ifa_broadcast = 0;
 759                         ifa->ifa_anycast = 0;
 760                 }
 761
 762                 ifa->ifa_address = ifa->ifa_local = sin->sin_addr.s_addr;
 763
 764                 if (!(dev->flags & IFF_POINTOPOINT)) {
 765                         ifa->ifa_prefixlen = inet_abc_len(ifa->ifa_address);
 766                         ifa->ifa_mask = inet_make_mask(ifa->ifa_prefixlen);
 767                         if ((dev->flags & IFF_BROADCAST) &&
 768                             ifa->ifa_prefixlen < 31)
 769                                 ifa->ifa_broadcast = ifa->ifa_address |
 770                                                      ~ifa->ifa_mask;
 771                 } else {
 772                         ifa->ifa_prefixlen = 32;
 773                         ifa->ifa_mask = inet_make_mask(32);
 774                 }
 775                 ret = inet_set_ifa(dev, ifa);
 776                 break;
 777
 778         case SIOCSIFBRDADDR:    /* Set the broadcast address */
 779                 ret = 0;
 780                 if (ifa->ifa_broadcast != sin->sin_addr.s_addr) {
 781                         inet_del_ifa(in_dev, ifap, 0);
 782                         ifa->ifa_broadcast = sin->sin_addr.s_addr;
 783                         inet_insert_ifa(ifa);
 784                 }
 785                 break;
 786
 787         case SIOCSIFDSTADDR:    /* Set the destination address */
 788                 ret = 0;
 789                 if (ifa->ifa_address == sin->sin_addr.s_addr)
 790                         break;
 791                 ret = -EINVAL;
 792                 if (inet_abc_len(sin->sin_addr.s_addr) < 0)
 793                         break;
 794                 ret = 0;
 795                 inet_del_ifa(in_dev, ifap, 0);
 796                 ifa->ifa_address = sin->sin_addr.s_addr;
 797                 inet_insert_ifa(ifa);
 798                 break;
 799
 800         case SIOCSIFNETMASK:    /* Set the netmask for the interface */
 801
 802                 /*
 803                  *      The mask we set must be legal.
 804                  */
 805                 ret = -EINVAL;
 806                 if (bad_mask(sin->sin_addr.s_addr, 0))
 807                         break;
 808                 ret = 0;
 809                 if (ifa->ifa_mask != sin->sin_addr.s_addr) {
 810                         __be32 old_mask = ifa->ifa_mask;
 811                         inet_del_ifa(in_dev, ifap, 0);
 812                         ifa->ifa_mask = sin->sin_addr.s_addr;
 813                         ifa->ifa_prefixlen = inet_mask_len(ifa->ifa_mask);
 814
 815                         /* See if current broadcast address matches
 816                          * with current netmask, then recalculate
 817                          * the broadcast address. Otherwise it's a
 818                          * funny address, so don't touch it since
 819                          * the user seems to know what (s)he's doing...
 820                          */
 821                         if ((dev->flags & IFF_BROADCAST) &&
 822                             (ifa->ifa_prefixlen < 31) &&
 823                             (ifa->ifa_broadcast ==
 824                              (ifa->ifa_local|~old_mask))) {
 825                                 ifa->ifa_broadcast = (ifa->ifa_local |
 826                                                       ~sin->sin_addr.s_addr);
 827                         }
 828                         inet_insert_ifa(ifa);
 829                 }
 830                 break;
 831         }
 832 done:
 833         rtnl_unlock();
 834 out:
 835         return ret;
 836 rarok:
 837         rtnl_unlock();
 838         ret = copy_to_user(arg, &ifr, sizeof(struct ifreq)) ? -EFAULT : 0;
 839         goto out;
 840 }
 841
 842 static int inet_gifconf(struct net_device *dev, char __user *buf, int len)
 843 {
 844         struct in_device *in_dev = __in_dev_get_rtnl(dev);
 845         struct in_ifaddr *ifa;
 846         struct ifreq ifr;
 847         int done = 0;
 848
 849         if (!in_dev || (ifa = in_dev->ifa_list) == NULL)
 850                 goto out;
 851
 852         for (; ifa; ifa = ifa->ifa_next) {
 853                 if (!buf) {
 854                         done += sizeof(ifr);
 855                         continue;
 856                 }
 857                 if (len < (int) sizeof(ifr))
 858                         break;
 859                 memset(&ifr, 0, sizeof(struct ifreq));
 860                 if (ifa->ifa_label)
 861                         strcpy(ifr.ifr_name, ifa->ifa_label);
 862                 else
 863                         strcpy(ifr.ifr_name, dev->name);
 864
 865                 (*(struct sockaddr_in *)&ifr.ifr_addr).sin_family = AF_INET;
 866                 (*(struct sockaddr_in *)&ifr.ifr_addr).sin_addr.s_addr =
 867                                                                 ifa->ifa_local;
 868
 869                 if (copy_to_user(buf, &ifr, sizeof(struct ifreq))) {
 870                         done = -EFAULT;
 871                         break;
 872                 }
 873                 buf  += sizeof(struct ifreq);
 874                 len  -= sizeof(struct ifreq);
 875                 done += sizeof(struct ifreq);
 876         }
 877 out:
 878         return done;
 879 }
 880
 881 __be32 inet_select_addr(const struct net_device *dev, __be32 dst, int scope)
 882 {
 883         __be32 addr = 0;
 884         struct in_device *in_dev;
 885
 886         rcu_read_lock();
 887         in_dev = __in_dev_get_rcu(dev);
 888         if (!in_dev)
 889                 goto no_in_dev;
 890
 891         for_primary_ifa(in_dev) {
 892                 if (ifa->ifa_scope > scope)
 893                         continue;
 894                 if (!dst || inet_ifa_match(dst, ifa)) {
 895                         addr = ifa->ifa_local;
 896                         break;
 897                 }
 898                 if (!addr)
 899                         addr = ifa->ifa_local;
 900         } endfor_ifa(in_dev);
 901 no_in_dev:
 902         rcu_read_unlock();
 903
 904         if (addr)
 905                 goto out;
 906
 907         /* Not loopback addresses on loopback should be preferred
 908            in this case. It is importnat that lo is the first interface
 909            in dev_base list.
 910          */
 911         read_lock(&dev_base_lock);
 912         rcu_read_lock();
 913         for_each_netdev(&init_net, dev) {
 914                 if ((in_dev = __in_dev_get_rcu(dev)) == NULL)
 915                         continue;
 916
 917                 for_primary_ifa(in_dev) {
 918                         if (ifa->ifa_scope != RT_SCOPE_LINK &&
 919                             ifa->ifa_scope <= scope) {
 920                                 addr = ifa->ifa_local;
 921                                 goto out_unlock_both;
 922                         }
 923                 } endfor_ifa(in_dev);
 924         }
 925 out_unlock_both:
 926         read_unlock(&dev_base_lock);
 927         rcu_read_unlock();
 928 out:
 929         return addr;
 930 }
 931
 932 static __be32 confirm_addr_indev(struct in_device *in_dev, __be32 dst,
 933                               __be32 local, int scope)
 934 {
 935         int same = 0;
 936         __be32 addr = 0;
 937
 938         for_ifa(in_dev) {
 939                 if (!addr &&
 940                     (local == ifa->ifa_local || !local) &&
 941                     ifa->ifa_scope <= scope) {
 942                         addr = ifa->ifa_local;
 943                         if (same)
 944                                 break;
 945                 }
 946                 if (!same) {
 947                         same = (!local || inet_ifa_match(local, ifa)) &&
 948                                 (!dst || inet_ifa_match(dst, ifa));
 949                         if (same && addr) {
 950                                 if (local || !dst)
 951                                         break;
 952                                 /* Is the selected addr into dst subnet? */
 953                                 if (inet_ifa_match(addr, ifa))
 954                                         break;
 955                                 /* No, then can we use new local src? */
 956                                 if (ifa->ifa_scope <= scope) {
 957                                         addr = ifa->ifa_local;
 958                                         break;
 959                                 }
 960                                 /* search for large dst subnet for addr */
 961                                 same = 0;
 962                         }
 963                 }
 964         } endfor_ifa(in_dev);
 965
 966         return same? addr : 0;
 967 }
 968
 969 /*
 970  * Confirm that local IP address exists using wildcards:
 971  * - dev: only on this interface, 0=any interface
 972  * - dst: only in the same subnet as dst, 0=any dst
 973  * - local: address, 0=autoselect the local address
 974  * - scope: maximum allowed scope value for the local address
 975  */
 976 __be32 inet_confirm_addr(const struct net_device *dev, __be32 dst, __be32 local, int scope)
 977 {
 978         __be32 addr = 0;
 979         struct in_device *in_dev;
 980
 981         if (dev) {
 982                 rcu_read_lock();
 983                 if ((in_dev = __in_dev_get_rcu(dev)))
 984                         addr = confirm_addr_indev(in_dev, dst, local, scope);
 985                 rcu_read_unlock();
 986
 987                 return addr;
 988         }
 989
 990         read_lock(&dev_base_lock);
 991         rcu_read_lock();
 992         for_each_netdev(&init_net, dev) {
 993                 if ((in_dev = __in_dev_get_rcu(dev))) {
 994                         addr = confirm_addr_indev(in_dev, dst, local, scope);
 995                         if (addr)
 996                                 break;
 997                 }
 998         }
 999         rcu_read_unlock();
1000         read_unlock(&dev_base_lock);
1001
1002         return addr;
1003 }
1004
1005 /*
1006  *      Device notifier
1007  */
1008
1009 int register_inetaddr_notifier(struct notifier_block *nb)
1010 {
1011         return blocking_notifier_chain_register(&inetaddr_chain, nb);
1012 }
1013
1014 int unregister_inetaddr_notifier(struct notifier_block *nb)
1015 {
1016         return blocking_notifier_chain_unregister(&inetaddr_chain, nb);
1017 }
1018
1019 /* Rename ifa_labels for a device name change. Make some effort to preserve existing
1020  * alias numbering and to create unique labels if possible.
1021 */
1022 static void inetdev_changename(struct net_device *dev, struct in_device *in_dev)
1023 {
1024         struct in_ifaddr *ifa;
1025         int named = 0;
1026
1027         for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
1028                 char old[IFNAMSIZ], *dot;
1029
1030                 memcpy(old, ifa->ifa_label, IFNAMSIZ);
1031                 memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
1032                 if (named++ == 0)
1033                         continue;
1034                 dot = strchr(old, ':');
1035                 if (dot == NULL) {
1036                         sprintf(old, ":%d", named);
1037                         dot = old;
1038                 }
1039                 if (strlen(dot) + strlen(dev->name) < IFNAMSIZ) {
1040                         strcat(ifa->ifa_label, dot);
1041                 } else {
1042                         strcpy(ifa->ifa_label + (IFNAMSIZ - strlen(dot) - 1), dot);
1043                 }
1044         }
1045 }
1046
1047 /* Called only under RTNL semaphore */
1048
1049 static int inetdev_event(struct notifier_block *this, unsigned long event,
1050                          void *ptr)
1051 {
1052         struct net_device *dev = ptr;
1053         struct in_device *in_dev = __in_dev_get_rtnl(dev);
1054
1055         if (dev->nd_net != &init_net)
1056                 return NOTIFY_DONE;
1057
1058         ASSERT_RTNL();
1059
1060         if (!in_dev) {
1061                 if (event == NETDEV_REGISTER) {
1062                         in_dev = inetdev_init(dev);
1063                         if (!in_dev)
1064                                 return notifier_from_errno(-ENOMEM);
1065                         if (dev->flags & IFF_LOOPBACK) {
1066                                 IN_DEV_CONF_SET(in_dev, NOXFRM, 1);
1067                                 IN_DEV_CONF_SET(in_dev, NOPOLICY, 1);
1068                         }
1069                 }
1070                 goto out;
1071         }
1072
1073         switch (event) {
1074         case NETDEV_REGISTER:
1075                 printk(KERN_DEBUG "inetdev_event: bug\n");
1076                 dev->ip_ptr = NULL;
1077                 break;
1078         case NETDEV_UP:
1079                 if (dev->mtu < 68)
1080                         break;
1081                 if (dev->flags & IFF_LOOPBACK) {
1082                         struct in_ifaddr *ifa;
1083                         if ((ifa = inet_alloc_ifa()) != NULL) {
1084                                 ifa->ifa_local =
1085                                   ifa->ifa_address = htonl(INADDR_LOOPBACK);
1086                                 ifa->ifa_prefixlen = 8;
1087                                 ifa->ifa_mask = inet_make_mask(8);
1088                                 in_dev_hold(in_dev);
1089                                 ifa->ifa_dev = in_dev;
1090                                 ifa->ifa_scope = RT_SCOPE_HOST;
1091                                 memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
1092                                 inet_insert_ifa(ifa);
1093                         }
1094                 }
1095                 ip_mc_up(in_dev);
1096                 break;
1097         case NETDEV_DOWN:
1098                 ip_mc_down(in_dev);
1099                 break;
1100         case NETDEV_CHANGEMTU:
1101                 if (dev->mtu >= 68)
1102                         break;
1103                 /* MTU falled under 68, disable IP */
1104         case NETDEV_UNREGISTER:
1105                 inetdev_destroy(in_dev);
1106                 break;
1107         case NETDEV_CHANGENAME:
1108                 /* Do not notify about label change, this event is
1109                  * not interesting to applications using netlink.
1110                  */
1111                 inetdev_changename(dev, in_dev);
1112
1113                 devinet_sysctl_unregister(in_dev);
1114                 devinet_sysctl_register(in_dev);
1115                 break;
1116         }
1117 out:
1118         return NOTIFY_DONE;
1119 }
1120
1121 static struct notifier_block ip_netdev_notifier = {
1122         .notifier_call =inetdev_event,
1123 };
1124
1125 static inline size_t inet_nlmsg_size(void)
1126 {
1127         return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
1128                + nla_total_size(4) /* IFA_ADDRESS */
1129                + nla_total_size(4) /* IFA_LOCAL */
1130                + nla_total_size(4) /* IFA_BROADCAST */
1131                + nla_total_size(4) /* IFA_ANYCAST */
1132                + nla_total_size(IFNAMSIZ); /* IFA_LABEL */
1133 }
1134
1135 static int inet_fill_ifaddr(struct sk_buff *skb, struct in_ifaddr *ifa,
1136                             u32 pid, u32 seq, int event, unsigned int flags)
1137 {
1138         struct ifaddrmsg *ifm;
1139         struct nlmsghdr  *nlh;
1140
1141         nlh = nlmsg_put(skb, pid, seq, event, sizeof(*ifm), flags);
1142         if (nlh == NULL)
1143                 return -EMSGSIZE;
1144
1145         ifm = nlmsg_data(nlh);
1146         ifm->ifa_family = AF_INET;
1147         ifm->ifa_prefixlen = ifa->ifa_prefixlen;
1148         ifm->ifa_flags = ifa->ifa_flags|IFA_F_PERMANENT;
1149         ifm->ifa_scope = ifa->ifa_scope;
1150         ifm->ifa_index = ifa->ifa_dev->dev->ifindex;
1151
1152         if (ifa->ifa_address)
1153                 NLA_PUT_BE32(skb, IFA_ADDRESS, ifa->ifa_address);
1154
1155         if (ifa->ifa_local)
1156                 NLA_PUT_BE32(skb, IFA_LOCAL, ifa->ifa_local);
1157
1158         if (ifa->ifa_broadcast)
1159                 NLA_PUT_BE32(skb, IFA_BROADCAST, ifa->ifa_broadcast);
1160
1161         if (ifa->ifa_anycast)
1162                 NLA_PUT_BE32(skb, IFA_ANYCAST, ifa->ifa_anycast);
1163
1164         if (ifa->ifa_label[0])
1165                 NLA_PUT_STRING(skb, IFA_LABEL, ifa->ifa_label);
1166
1167         return nlmsg_end(skb, nlh);
1168
1169 nla_put_failure:
1170         nlmsg_cancel(skb, nlh);
1171         return -EMSGSIZE;
1172 }
1173
1174 static int inet_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
1175 {
1176         struct net *net = skb->sk->sk_net;
1177         int idx, ip_idx;
1178         struct net_device *dev;
1179         struct in_device *in_dev;
1180         struct in_ifaddr *ifa;
1181         int s_ip_idx, s_idx = cb->args[0];
1182
1183         if (net != &init_net)
1184                 return 0;
1185
1186         s_ip_idx = ip_idx = cb->args[1];
1187         idx = 0;
1188         for_each_netdev(&init_net, dev) {
1189                 if (idx < s_idx)
1190                         goto cont;
1191                 if (idx > s_idx)
1192                         s_ip_idx = 0;
1193                 if ((in_dev = __in_dev_get_rtnl(dev)) == NULL)
1194                         goto cont;
1195
1196                 for (ifa = in_dev->ifa_list, ip_idx = 0; ifa;
1197                      ifa = ifa->ifa_next, ip_idx++) {
1198                         if (ip_idx < s_ip_idx)
1199                                 continue;
1200                         if (inet_fill_ifaddr(skb, ifa, NETLINK_CB(cb->skb).pid,
1201                                              cb->nlh->nlmsg_seq,
1202                                              RTM_NEWADDR, NLM_F_MULTI) <= 0)
1203                                 goto done;
1204                 }
1205 cont:
1206                 idx++;
1207         }
1208
1209 done:
1210         cb->args[0] = idx;
1211         cb->args[1] = ip_idx;
1212
1213         return skb->len;
1214 }
1215
1216 static void rtmsg_ifa(int event, struct in_ifaddr* ifa, struct nlmsghdr *nlh,
1217                       u32 pid)
1218 {
1219         struct sk_buff *skb;
1220         u32 seq = nlh ? nlh->nlmsg_seq : 0;
1221         int err = -ENOBUFS;
1222
1223         skb = nlmsg_new(inet_nlmsg_size(), GFP_KERNEL);
1224         if (skb == NULL)
1225                 goto errout;
1226
1227         err = inet_fill_ifaddr(skb, ifa, pid, seq, event, 0);
1228         if (err < 0) {
1229                 /* -EMSGSIZE implies BUG in inet_nlmsg_size() */
1230                 WARN_ON(err == -EMSGSIZE);
1231                 kfree_skb(skb);
1232                 goto errout;
1233         }
1234         err = rtnl_notify(skb, &init_net, pid, RTNLGRP_IPV4_IFADDR, nlh, GFP_KERNEL);
1235 errout:
1236         if (err < 0)
1237                 rtnl_set_sk_err(&init_net, RTNLGRP_IPV4_IFADDR, err);
1238 }
1239
1240 #ifdef CONFIG_SYSCTL
1241
1242 static void devinet_copy_dflt_conf(struct net *net, int i)
1243 {
1244         struct net_device *dev;
1245
1246         read_lock(&dev_base_lock);
1247         for_each_netdev(net, dev) {
1248                 struct in_device *in_dev;
1249                 rcu_read_lock();
1250                 in_dev = __in_dev_get_rcu(dev);
1251                 if (in_dev && !test_bit(i, in_dev->cnf.state))
1252                         in_dev->cnf.data[i] = net->ipv4.devconf_dflt->data[i];
1253                 rcu_read_unlock();
1254         }
1255         read_unlock(&dev_base_lock);
1256 }
1257
1258 static void inet_forward_change(struct net *net)
1259 {
1260         struct net_device *dev;
1261         int on = IPV4_DEVCONF_ALL(net, FORWARDING);
1262
1263         IPV4_DEVCONF_ALL(net, ACCEPT_REDIRECTS) = !on;
1264         IPV4_DEVCONF_DFLT(net, FORWARDING) = on;
1265
1266         read_lock(&dev_base_lock);
1267         for_each_netdev(net, dev) {
1268                 struct in_device *in_dev;
1269                 rcu_read_lock();
1270                 in_dev = __in_dev_get_rcu(dev);
1271                 if (in_dev)
1272                         IN_DEV_CONF_SET(in_dev, FORWARDING, on);
1273                 rcu_read_unlock();
1274         }
1275         read_unlock(&dev_base_lock);
1276
1277         rt_cache_flush(0);
1278 }
1279
1280 static int devinet_conf_proc(ctl_table *ctl, int write,
1281                              struct file* filp, void __user *buffer,
1282                              size_t *lenp, loff_t *ppos)
1283 {
1284         int ret = proc_dointvec(ctl, write, filp, buffer, lenp, ppos);
1285
1286         if (write) {
1287                 struct ipv4_devconf *cnf = ctl->extra1;
1288                 struct net *net = ctl->extra2;
1289                 int i = (int *)ctl->data - cnf->data;
1290
1291                 set_bit(i, cnf->state);
1292
1293                 if (cnf == net->ipv4.devconf_dflt)
1294                         devinet_copy_dflt_conf(net, i);
1295         }
1296
1297         return ret;
1298 }
1299
1300 static int devinet_conf_sysctl(ctl_table *table, int __user *name, int nlen,
1301                                void __user *oldval, size_t __user *oldlenp,
1302                                void __user *newval, size_t newlen)
1303 {
1304         struct ipv4_devconf *cnf;
1305         struct net *net;
1306         int *valp = table->data;
1307         int new;
1308         int i;
1309
1310         if (!newval || !newlen)
1311                 return 0;
1312
1313         if (newlen != sizeof(int))
1314                 return -EINVAL;
1315
1316         if (get_user(new, (int __user *)newval))
1317                 return -EFAULT;
1318
1319         if (new == *valp)
1320                 return 0;
1321
1322         if (oldval && oldlenp) {
1323                 size_t len;
1324
1325                 if (get_user(len, oldlenp))
1326                         return -EFAULT;
1327
1328                 if (len) {
1329                         if (len > table->maxlen)
1330                                 len = table->maxlen;
1331                         if (copy_to_user(oldval, valp, len))
1332                                 return -EFAULT;
1333                         if (put_user(len, oldlenp))
1334                                 return -EFAULT;
1335                 }
1336         }
1337
1338         *valp = new;
1339
1340         cnf = table->extra1;
1341         net = table->extra2;
1342         i = (int *)table->data - cnf->data;
1343
1344         set_bit(i, cnf->state);
1345
1346         if (cnf == net->ipv4.devconf_dflt)
1347                 devinet_copy_dflt_conf(net, i);
1348
1349         return 1;
1350 }
1351
1352 static int devinet_sysctl_forward(ctl_table *ctl, int write,
1353                                   struct file* filp, void __user *buffer,
1354                                   size_t *lenp, loff_t *ppos)
1355 {
1356         int *valp = ctl->data;
1357         int val = *valp;
1358         int ret = proc_dointvec(ctl, write, filp, buffer, lenp, ppos);
1359
1360         if (write && *valp != val) {
1361                 struct net *net = ctl->extra2;
1362
1363                 if (valp == &IPV4_DEVCONF_ALL(net, FORWARDING))
1364                         inet_forward_change(net);
1365                 else if (valp != &IPV4_DEVCONF_DFLT(net, FORWARDING))
1366                         rt_cache_flush(0);
1367         }
1368
1369         return ret;
1370 }
1371
1372 int ipv4_doint_and_flush(ctl_table *ctl, int write,
1373                          struct file* filp, void __user *buffer,
1374                          size_t *lenp, loff_t *ppos)
1375 {
1376         int *valp = ctl->data;
1377         int val = *valp;
1378         int ret = proc_dointvec(ctl, write, filp, buffer, lenp, ppos);
1379
1380         if (write && *valp != val)
1381                 rt_cache_flush(0);
1382
1383         return ret;
1384 }
1385
1386 int ipv4_doint_and_flush_strategy(ctl_table *table, int __user *name, int nlen,
1387                                   void __user *oldval, size_t __user *oldlenp,
1388                                   void __user *newval, size_t newlen)
1389 {
1390         int ret = devinet_conf_sysctl(table, name, nlen, oldval, oldlenp,
1391                                       newval, newlen);
1392
1393         if (ret == 1)
1394                 rt_cache_flush(0);
1395
1396         return ret;
1397 }
1398
1399
1400 #define DEVINET_SYSCTL_ENTRY(attr, name, mval, proc, sysctl) \
1401         { \
1402                 .ctl_name       = NET_IPV4_CONF_ ## attr, \
1403                 .procname       = name, \
1404                 .data           = ipv4_devconf.data + \
1405                                   NET_IPV4_CONF_ ## attr - 1, \
1406                 .maxlen         = sizeof(int), \
1407                 .mode           = mval, \
1408                 .proc_handler   = proc, \
1409                 .strategy       = sysctl, \
1410                 .extra1         = &ipv4_devconf, \
1411         }
1412
1413 #define DEVINET_SYSCTL_RW_ENTRY(attr, name) \
1414         DEVINET_SYSCTL_ENTRY(attr, name, 0644, devinet_conf_proc, \
1415                              devinet_conf_sysctl)
1416
1417 #define DEVINET_SYSCTL_RO_ENTRY(attr, name) \
1418         DEVINET_SYSCTL_ENTRY(attr, name, 0444, devinet_conf_proc, \
1419                              devinet_conf_sysctl)
1420
1421 #define DEVINET_SYSCTL_COMPLEX_ENTRY(attr, name, proc, sysctl) \
1422         DEVINET_SYSCTL_ENTRY(attr, name, 0644, proc, sysctl)
1423
1424 #define DEVINET_SYSCTL_FLUSHING_ENTRY(attr, name) \
1425         DEVINET_SYSCTL_COMPLEX_ENTRY(attr, name, ipv4_doint_and_flush, \
1426                                      ipv4_doint_and_flush_strategy)
1427
1428 static struct devinet_sysctl_table {
1429         struct ctl_table_header *sysctl_header;
1430         struct ctl_table devinet_vars[__NET_IPV4_CONF_MAX];
1431         char *dev_name;
1432 } devinet_sysctl = {
1433         .devinet_vars = {
1434                 DEVINET_SYSCTL_COMPLEX_ENTRY(FORWARDING, "forwarding",
1435                                              devinet_sysctl_forward,
1436                                              devinet_conf_sysctl),
1437                 DEVINET_SYSCTL_RO_ENTRY(MC_FORWARDING, "mc_forwarding"),
1438
1439                 DEVINET_SYSCTL_RW_ENTRY(ACCEPT_REDIRECTS, "accept_redirects"),
1440                 DEVINET_SYSCTL_RW_ENTRY(SECURE_REDIRECTS, "secure_redirects"),
1441                 DEVINET_SYSCTL_RW_ENTRY(SHARED_MEDIA, "shared_media"),
1442                 DEVINET_SYSCTL_RW_ENTRY(RP_FILTER, "rp_filter"),
1443                 DEVINET_SYSCTL_RW_ENTRY(SEND_REDIRECTS, "send_redirects"),
1444                 DEVINET_SYSCTL_RW_ENTRY(ACCEPT_SOURCE_ROUTE,
1445                                         "accept_source_route"),
1446                 DEVINET_SYSCTL_RW_ENTRY(PROXY_ARP, "proxy_arp"),
1447                 DEVINET_SYSCTL_RW_ENTRY(MEDIUM_ID, "medium_id"),
1448                 DEVINET_SYSCTL_RW_ENTRY(BOOTP_RELAY, "bootp_relay"),
1449                 DEVINET_SYSCTL_RW_ENTRY(LOG_MARTIANS, "log_martians"),
1450                 DEVINET_SYSCTL_RW_ENTRY(TAG, "tag"),
1451                 DEVINET_SYSCTL_RW_ENTRY(ARPFILTER, "arp_filter"),
1452                 DEVINET_SYSCTL_RW_ENTRY(ARP_ANNOUNCE, "arp_announce"),
1453                 DEVINET_SYSCTL_RW_ENTRY(ARP_IGNORE, "arp_ignore"),
1454                 DEVINET_SYSCTL_RW_ENTRY(ARP_ACCEPT, "arp_accept"),
1455
1456                 DEVINET_SYSCTL_FLUSHING_ENTRY(NOXFRM, "disable_xfrm"),
1457                 DEVINET_SYSCTL_FLUSHING_ENTRY(NOPOLICY, "disable_policy"),
1458                 DEVINET_SYSCTL_FLUSHING_ENTRY(FORCE_IGMP_VERSION,
1459                                               "force_igmp_version"),
1460                 DEVINET_SYSCTL_FLUSHING_ENTRY(PROMOTE_SECONDARIES,
1461                                               "promote_secondaries"),
1462         },
1463 };
1464
1465 static int __devinet_sysctl_register(struct net *net, char *dev_name,
1466                 int ctl_name, struct ipv4_devconf *p)
1467 {
1468         int i;
1469         struct devinet_sysctl_table *t;
1470
1471 #define DEVINET_CTL_PATH_DEV    3
1472
1473         struct ctl_path devinet_ctl_path[] = {
1474                 { .procname = "net", .ctl_name = CTL_NET, },
1475                 { .procname = "ipv4", .ctl_name = NET_IPV4, },
1476                 { .procname = "conf", .ctl_name = NET_IPV4_CONF, },
1477                 { /* to be set */ },
1478                 { },
1479         };
1480
1481         t = kmemdup(&devinet_sysctl, sizeof(*t), GFP_KERNEL);
1482         if (!t)
1483                 goto out;
1484
1485         for (i = 0; i < ARRAY_SIZE(t->devinet_vars) - 1; i++) {
1486                 t->devinet_vars[i].data += (char *)p - (char *)&ipv4_devconf;
1487                 t->devinet_vars[i].extra1 = p;
1488                 t->devinet_vars[i].extra2 = net;
1489         }
1490
1491         /*
1492          * Make a copy of dev_name, because '.procname' is regarded as const
1493          * by sysctl and we wouldn't want anyone to change it under our feet
1494          * (see SIOCSIFNAME).
1495          */
1496         t->dev_name = kstrdup(dev_name, GFP_KERNEL);
1497         if (!t->dev_name)
1498                 goto free;
1499
1500         devinet_ctl_path[DEVINET_CTL_PATH_DEV].procname = t->dev_name;
1501         devinet_ctl_path[DEVINET_CTL_PATH_DEV].ctl_name = ctl_name;
1502
1503         t->sysctl_header = register_net_sysctl_table(net, devinet_ctl_path,
1504                         t->devinet_vars);
1505         if (!t->sysctl_header)
1506                 goto free_procname;
1507
1508         p->sysctl = t;
1509         return 0;
1510
1511 free_procname:
1512         kfree(t->dev_name);
1513 free:
1514         kfree(t);
1515 out:
1516         return -ENOBUFS;
1517 }
1518
1519 static void __devinet_sysctl_unregister(struct ipv4_devconf *cnf)
1520 {
1521         struct devinet_sysctl_table *t = cnf->sysctl;
1522
1523         if (t == NULL)
1524                 return;
1525
1526         cnf->sysctl = NULL;
1527         unregister_sysctl_table(t->sysctl_header);
1528         kfree(t->dev_name);
1529         kfree(t);
1530 }
1531
1532 static void devinet_sysctl_register(struct in_device *idev)
1533 {
1534         neigh_sysctl_register(idev->dev, idev->arp_parms, NET_IPV4,
1535                         NET_IPV4_NEIGH, "ipv4", NULL, NULL);
1536         __devinet_sysctl_register(idev->dev->nd_net, idev->dev->name,
1537                         idev->dev->ifindex, &idev->cnf);
1538 }
1539
1540 static void devinet_sysctl_unregister(struct in_device *idev)
1541 {
1542         __devinet_sysctl_unregister(&idev->cnf);
1543         neigh_sysctl_unregister(idev->arp_parms);
1544 }
1545 #endif
1546
1547 static struct ctl_table ctl_forward_entry[] = {
1548         {
1549                 .ctl_name       = NET_IPV4_FORWARD,
1550                 .procname       = "ip_forward",
1551                 .data           = &ipv4_devconf.data[
1552                                         NET_IPV4_CONF_FORWARDING - 1],
1553                 .maxlen         = sizeof(int),
1554                 .mode           = 0644,
1555                 .proc_handler   = devinet_sysctl_forward,
1556                 .strategy       = devinet_conf_sysctl,
1557                 .extra1         = &ipv4_devconf,
1558                 .extra2         = &init_net,
1559         },
1560         { },
1561 };
1562
1563 static __net_initdata struct ctl_path net_ipv4_path[] = {
1564         { .procname = "net", .ctl_name = CTL_NET, },
1565         { .procname = "ipv4", .ctl_name = NET_IPV4, },
1566         { },
1567 };
1568
1569 static __net_init int devinet_init_net(struct net *net)
1570 {
1571         int err;
1572         struct ctl_table *tbl;
1573         struct ipv4_devconf *all, *dflt;
1574         struct ctl_table_header *forw_hdr;
1575
1576         err = -ENOMEM;
1577         all = &ipv4_devconf;
1578         dflt = &ipv4_devconf_dflt;
1579         tbl = ctl_forward_entry;
1580
1581         if (net != &init_net) {
1582                 all = kmemdup(all, sizeof(ipv4_devconf), GFP_KERNEL);
1583                 if (all == NULL)
1584                         goto err_alloc_all;
1585
1586                 dflt = kmemdup(dflt, sizeof(ipv4_devconf_dflt), GFP_KERNEL);
1587                 if (dflt == NULL)
1588                         goto err_alloc_dflt;
1589
1590                 tbl = kmemdup(tbl, sizeof(ctl_forward_entry), GFP_KERNEL);
1591                 if (tbl == NULL)
1592                         goto err_alloc_ctl;
1593
1594                 tbl[0].data = &all->data[NET_IPV4_CONF_FORWARDING - 1];
1595                 tbl[0].extra1 = all;
1596                 tbl[0].extra2 = net;
1597         }
1598
1599 #ifdef CONFIG_SYSCTL
1600         err = __devinet_sysctl_register(net, "all",
1601                         NET_PROTO_CONF_ALL, all);
1602         if (err < 0)
1603                 goto err_reg_all;
1604
1605         err = __devinet_sysctl_register(net, "default",
1606                         NET_PROTO_CONF_DEFAULT, dflt);
1607         if (err < 0)
1608                 goto err_reg_dflt;
1609
1610         err = -ENOMEM;
1611         forw_hdr = register_net_sysctl_table(net, net_ipv4_path, tbl);
1612         if (forw_hdr == NULL)
1613                 goto err_reg_ctl;
1614 #endif
1615
1616         net->ipv4.forw_hdr = forw_hdr;
1617         net->ipv4.devconf_all = all;
1618         net->ipv4.devconf_dflt = dflt;
1619         return 0;
1620
1621 #ifdef CONFIG_SYSCTL
1622 err_reg_ctl:
1623         __devinet_sysctl_unregister(dflt);
1624 err_reg_dflt:
1625         __devinet_sysctl_unregister(all);
1626 err_reg_all:
1627         if (tbl != ctl_forward_entry)
1628                 kfree(tbl);
1629 #endif
1630 err_alloc_ctl:
1631         if (dflt != &ipv4_devconf_dflt)
1632                 kfree(dflt);
1633 err_alloc_dflt:
1634         if (all != &ipv4_devconf)
1635                 kfree(all);
1636 err_alloc_all:
1637         return err;
1638 }
1639
1640 static __net_exit void devinet_exit_net(struct net *net)
1641 {
1642         struct ctl_table *tbl;
1643
1644         tbl = net->ipv4.forw_hdr->ctl_table_arg;
1645 #ifdef CONFIG_SYSCTL
1646         unregister_net_sysctl_table(net->ipv4.forw_hdr);
1647         __devinet_sysctl_unregister(net->ipv4.devconf_dflt);
1648         __devinet_sysctl_unregister(net->ipv4.devconf_all);
1649 #endif
1650         kfree(tbl);
1651         kfree(net->ipv4.devconf_dflt);
1652         kfree(net->ipv4.devconf_all);
1653 }
1654
1655 static __net_initdata struct pernet_operations devinet_ops = {
1656         .init = devinet_init_net,
1657         .exit = devinet_exit_net,
1658 };
1659
1660 void __init devinet_init(void)
1661 {
1662         register_pernet_subsys(&devinet_ops);
1663
1664         register_gifconf(PF_INET, inet_gifconf);
1665         register_netdevice_notifier(&ip_netdev_notifier);
1666
1667         rtnl_register(PF_INET, RTM_NEWADDR, inet_rtm_newaddr, NULL);
1668         rtnl_register(PF_INET, RTM_DELADDR, inet_rtm_deladdr, NULL);
1669         rtnl_register(PF_INET, RTM_GETADDR, NULL, inet_dump_ifaddr);
1670 }
1671
1672 EXPORT_SYMBOL(in_dev_finish_destroy);
1673 EXPORT_SYMBOL(inet_select_addr);
1674 EXPORT_SYMBOL(inetdev_by_index);
1675 EXPORT_SYMBOL(register_inetaddr_notifier);
1676 EXPORT_SYMBOL(unregister_inetaddr_notifier);