git.oblomov.eu Git - linux-2.6/blob - net/ipv4/devinet.c

   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
  66 struct ipv4_devconf ipv4_devconf = {
  67         .accept_redirects = 1,
  68         .send_redirects =  1,
  69         .secure_redirects = 1,
  70         .shared_media =   1,
  71 };
  72
  73 static struct ipv4_devconf ipv4_devconf_dflt = {
  74         .accept_redirects =  1,
  75         .send_redirects =    1,
  76         .secure_redirects =  1,
  77         .shared_media =      1,
  78         .accept_source_route = 1,
  79 };
  80
  81 static struct nla_policy ifa_ipv4_policy[IFA_MAX+1] __read_mostly = {
  82         [IFA_LOCAL]             = { .type = NLA_U32 },
  83         [IFA_ADDRESS]           = { .type = NLA_U32 },
  84         [IFA_BROADCAST]         = { .type = NLA_U32 },
  85         [IFA_ANYCAST]           = { .type = NLA_U32 },
  86         [IFA_LABEL]             = { .type = NLA_STRING, .len = IFNAMSIZ - 1 },
  87 };
  88
  89 static void rtmsg_ifa(int event, struct in_ifaddr *, struct nlmsghdr *, u32);
  90
  91 static BLOCKING_NOTIFIER_HEAD(inetaddr_chain);
  92 static void inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap,
  93                          int destroy);
  94 #ifdef CONFIG_SYSCTL
  95 static void devinet_sysctl_register(struct in_device *in_dev,
  96                                     struct ipv4_devconf *p);
  97 static void devinet_sysctl_unregister(struct ipv4_devconf *p);
  98 #endif
  99
 100 /* Locks all the inet devices. */
 101
 102 static struct in_ifaddr *inet_alloc_ifa(void)
 103 {
 104         struct in_ifaddr *ifa = kzalloc(sizeof(*ifa), GFP_KERNEL);
 105
 106         if (ifa) {
 107                 INIT_RCU_HEAD(&ifa->rcu_head);
 108         }
 109
 110         return ifa;
 111 }
 112
 113 static void inet_rcu_free_ifa(struct rcu_head *head)
 114 {
 115         struct in_ifaddr *ifa = container_of(head, struct in_ifaddr, rcu_head);
 116         if (ifa->ifa_dev)
 117                 in_dev_put(ifa->ifa_dev);
 118         kfree(ifa);
 119 }
 120
 121 static inline void inet_free_ifa(struct in_ifaddr *ifa)
 122 {
 123         call_rcu(&ifa->rcu_head, inet_rcu_free_ifa);
 124 }
 125
 126 void in_dev_finish_destroy(struct in_device *idev)
 127 {
 128         struct net_device *dev = idev->dev;
 129
 130         BUG_TRAP(!idev->ifa_list);
 131         BUG_TRAP(!idev->mc_list);
 132 #ifdef NET_REFCNT_DEBUG
 133         printk(KERN_DEBUG "in_dev_finish_destroy: %p=%s\n",
 134                idev, dev ? dev->name : "NIL");
 135 #endif
 136         dev_put(dev);
 137         if (!idev->dead)
 138                 printk("Freeing alive in_device %p\n", idev);
 139         else {
 140                 kfree(idev);
 141         }
 142 }
 143
 144 struct in_device *inetdev_init(struct net_device *dev)
 145 {
 146         struct in_device *in_dev;
 147
 148         ASSERT_RTNL();
 149
 150         in_dev = kzalloc(sizeof(*in_dev), GFP_KERNEL);
 151         if (!in_dev)
 152                 goto out;
 153         INIT_RCU_HEAD(&in_dev->rcu_head);
 154         memcpy(&in_dev->cnf, &ipv4_devconf_dflt, sizeof(in_dev->cnf));
 155         in_dev->cnf.sysctl = NULL;
 156         in_dev->dev = dev;
 157         if ((in_dev->arp_parms = neigh_parms_alloc(dev, &arp_tbl)) == NULL)
 158                 goto out_kfree;
 159         /* Reference in_dev->dev */
 160         dev_hold(dev);
 161 #ifdef CONFIG_SYSCTL
 162         neigh_sysctl_register(dev, in_dev->arp_parms, NET_IPV4,
 163                               NET_IPV4_NEIGH, "ipv4", NULL, NULL);
 164 #endif
 165
 166         /* Account for reference dev->ip_ptr (below) */
 167         in_dev_hold(in_dev);
 168
 169 #ifdef CONFIG_SYSCTL
 170         devinet_sysctl_register(in_dev, &in_dev->cnf);
 171 #endif
 172         ip_mc_init_dev(in_dev);
 173         if (dev->flags & IFF_UP)
 174                 ip_mc_up(in_dev);
 175
 176         /* we can receive as soon as ip_ptr is set -- do this last */
 177         rcu_assign_pointer(dev->ip_ptr, in_dev);
 178 out:
 179         return in_dev;
 180 out_kfree:
 181         kfree(in_dev);
 182         in_dev = NULL;
 183         goto out;
 184 }
 185
 186 static void in_dev_rcu_put(struct rcu_head *head)
 187 {
 188         struct in_device *idev = container_of(head, struct in_device, rcu_head);
 189         in_dev_put(idev);
 190 }
 191
 192 static void inetdev_destroy(struct in_device *in_dev)
 193 {
 194         struct in_ifaddr *ifa;
 195         struct net_device *dev;
 196
 197         ASSERT_RTNL();
 198
 199         dev = in_dev->dev;
 200         if (dev == &loopback_dev)
 201                 return;
 202
 203         in_dev->dead = 1;
 204
 205         ip_mc_destroy_dev(in_dev);
 206
 207         while ((ifa = in_dev->ifa_list) != NULL) {
 208                 inet_del_ifa(in_dev, &in_dev->ifa_list, 0);
 209                 inet_free_ifa(ifa);
 210         }
 211
 212 #ifdef CONFIG_SYSCTL
 213         devinet_sysctl_unregister(&in_dev->cnf);
 214 #endif
 215
 216         dev->ip_ptr = NULL;
 217
 218 #ifdef CONFIG_SYSCTL
 219         neigh_sysctl_unregister(in_dev->arp_parms);
 220 #endif
 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                 if (!in_dev->ifa_list)
 328                         inetdev_destroy(in_dev);
 329         }
 330 }
 331
 332 static void inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap,
 333                          int destroy)
 334 {
 335         __inet_del_ifa(in_dev, ifap, destroy, NULL, 0);
 336 }
 337
 338 static int __inet_insert_ifa(struct in_ifaddr *ifa, struct nlmsghdr *nlh,
 339                              u32 pid)
 340 {
 341         struct in_device *in_dev = ifa->ifa_dev;
 342         struct in_ifaddr *ifa1, **ifap, **last_primary;
 343
 344         ASSERT_RTNL();
 345
 346         if (!ifa->ifa_local) {
 347                 inet_free_ifa(ifa);
 348                 return 0;
 349         }
 350
 351         ifa->ifa_flags &= ~IFA_F_SECONDARY;
 352         last_primary = &in_dev->ifa_list;
 353
 354         for (ifap = &in_dev->ifa_list; (ifa1 = *ifap) != NULL;
 355              ifap = &ifa1->ifa_next) {
 356                 if (!(ifa1->ifa_flags & IFA_F_SECONDARY) &&
 357                     ifa->ifa_scope <= ifa1->ifa_scope)
 358                         last_primary = &ifa1->ifa_next;
 359                 if (ifa1->ifa_mask == ifa->ifa_mask &&
 360                     inet_ifa_match(ifa1->ifa_address, ifa)) {
 361                         if (ifa1->ifa_local == ifa->ifa_local) {
 362                                 inet_free_ifa(ifa);
 363                                 return -EEXIST;
 364                         }
 365                         if (ifa1->ifa_scope != ifa->ifa_scope) {
 366                                 inet_free_ifa(ifa);
 367                                 return -EINVAL;
 368                         }
 369                         ifa->ifa_flags |= IFA_F_SECONDARY;
 370                 }
 371         }
 372
 373         if (!(ifa->ifa_flags & IFA_F_SECONDARY)) {
 374                 net_srandom(ifa->ifa_local);
 375                 ifap = last_primary;
 376         }
 377
 378         ifa->ifa_next = *ifap;
 379         *ifap = ifa;
 380
 381         /* Send message first, then call notifier.
 382            Notifier will trigger FIB update, so that
 383            listeners of netlink will know about new ifaddr */
 384         rtmsg_ifa(RTM_NEWADDR, ifa, nlh, pid);
 385         blocking_notifier_call_chain(&inetaddr_chain, NETDEV_UP, ifa);
 386
 387         return 0;
 388 }
 389
 390 static int inet_insert_ifa(struct in_ifaddr *ifa)
 391 {
 392         return __inet_insert_ifa(ifa, NULL, 0);
 393 }
 394
 395 static int inet_set_ifa(struct net_device *dev, struct in_ifaddr *ifa)
 396 {
 397         struct in_device *in_dev = __in_dev_get_rtnl(dev);
 398
 399         ASSERT_RTNL();
 400
 401         if (!in_dev) {
 402                 in_dev = inetdev_init(dev);
 403                 if (!in_dev) {
 404                         inet_free_ifa(ifa);
 405                         return -ENOBUFS;
 406                 }
 407         }
 408         if (ifa->ifa_dev != in_dev) {
 409                 BUG_TRAP(!ifa->ifa_dev);
 410                 in_dev_hold(in_dev);
 411                 ifa->ifa_dev = in_dev;
 412         }
 413         if (LOOPBACK(ifa->ifa_local))
 414                 ifa->ifa_scope = RT_SCOPE_HOST;
 415         return inet_insert_ifa(ifa);
 416 }
 417
 418 struct in_device *inetdev_by_index(int ifindex)
 419 {
 420         struct net_device *dev;
 421         struct in_device *in_dev = NULL;
 422         read_lock(&dev_base_lock);
 423         dev = __dev_get_by_index(ifindex);
 424         if (dev)
 425                 in_dev = in_dev_get(dev);
 426         read_unlock(&dev_base_lock);
 427         return in_dev;
 428 }
 429
 430 /* Called only from RTNL semaphored context. No locks. */
 431
 432 struct in_ifaddr *inet_ifa_byprefix(struct in_device *in_dev, __be32 prefix,
 433                                     __be32 mask)
 434 {
 435         ASSERT_RTNL();
 436
 437         for_primary_ifa(in_dev) {
 438                 if (ifa->ifa_mask == mask && inet_ifa_match(prefix, ifa))
 439                         return ifa;
 440         } endfor_ifa(in_dev);
 441         return NULL;
 442 }
 443
 444 static int inet_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 445 {
 446         struct nlattr *tb[IFA_MAX+1];
 447         struct in_device *in_dev;
 448         struct ifaddrmsg *ifm;
 449         struct in_ifaddr *ifa, **ifap;
 450         int err = -EINVAL;
 451
 452         ASSERT_RTNL();
 453
 454         err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv4_policy);
 455         if (err < 0)
 456                 goto errout;
 457
 458         ifm = nlmsg_data(nlh);
 459         in_dev = inetdev_by_index(ifm->ifa_index);
 460         if (in_dev == NULL) {
 461                 err = -ENODEV;
 462                 goto errout;
 463         }
 464
 465         __in_dev_put(in_dev);
 466
 467         for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL;
 468              ifap = &ifa->ifa_next) {
 469                 if (tb[IFA_LOCAL] &&
 470                     ifa->ifa_local != nla_get_be32(tb[IFA_LOCAL]))
 471                         continue;
 472
 473                 if (tb[IFA_LABEL] && nla_strcmp(tb[IFA_LABEL], ifa->ifa_label))
 474                         continue;
 475
 476                 if (tb[IFA_ADDRESS] &&
 477                     (ifm->ifa_prefixlen != ifa->ifa_prefixlen ||
 478                     !inet_ifa_match(nla_get_be32(tb[IFA_ADDRESS]), ifa)))
 479                         continue;
 480
 481                 __inet_del_ifa(in_dev, ifap, 1, nlh, NETLINK_CB(skb).pid);
 482                 return 0;
 483         }
 484
 485         err = -EADDRNOTAVAIL;
 486 errout:
 487         return err;
 488 }
 489
 490 static struct in_ifaddr *rtm_to_ifaddr(struct nlmsghdr *nlh)
 491 {
 492         struct nlattr *tb[IFA_MAX+1];
 493         struct in_ifaddr *ifa;
 494         struct ifaddrmsg *ifm;
 495         struct net_device *dev;
 496         struct in_device *in_dev;
 497         int err = -EINVAL;
 498
 499         err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv4_policy);
 500         if (err < 0)
 501                 goto errout;
 502
 503         ifm = nlmsg_data(nlh);
 504         if (ifm->ifa_prefixlen > 32 || tb[IFA_LOCAL] == NULL) {
 505                 err = -EINVAL;
 506                 goto errout;
 507         }
 508
 509         dev = __dev_get_by_index(ifm->ifa_index);
 510         if (dev == NULL) {
 511                 err = -ENODEV;
 512                 goto errout;
 513         }
 514
 515         in_dev = __in_dev_get_rtnl(dev);
 516         if (in_dev == NULL) {
 517                 in_dev = inetdev_init(dev);
 518                 if (in_dev == NULL) {
 519                         err = -ENOBUFS;
 520                         goto errout;
 521                 }
 522         }
 523
 524         ifa = inet_alloc_ifa();
 525         if (ifa == NULL) {
 526                 /*
 527                  * A potential indev allocation can be left alive, it stays
 528                  * assigned to its device and is destroy with it.
 529                  */
 530                 err = -ENOBUFS;
 531                 goto errout;
 532         }
 533
 534         in_dev_hold(in_dev);
 535
 536         if (tb[IFA_ADDRESS] == NULL)
 537                 tb[IFA_ADDRESS] = tb[IFA_LOCAL];
 538
 539         ifa->ifa_prefixlen = ifm->ifa_prefixlen;
 540         ifa->ifa_mask = inet_make_mask(ifm->ifa_prefixlen);
 541         ifa->ifa_flags = ifm->ifa_flags;
 542         ifa->ifa_scope = ifm->ifa_scope;
 543         ifa->ifa_dev = in_dev;
 544
 545         ifa->ifa_local = nla_get_be32(tb[IFA_LOCAL]);
 546         ifa->ifa_address = nla_get_be32(tb[IFA_ADDRESS]);
 547
 548         if (tb[IFA_BROADCAST])
 549                 ifa->ifa_broadcast = nla_get_be32(tb[IFA_BROADCAST]);
 550
 551         if (tb[IFA_ANYCAST])
 552                 ifa->ifa_anycast = nla_get_be32(tb[IFA_ANYCAST]);
 553
 554         if (tb[IFA_LABEL])
 555                 nla_strlcpy(ifa->ifa_label, tb[IFA_LABEL], IFNAMSIZ);
 556         else
 557                 memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
 558
 559         return ifa;
 560
 561 errout:
 562         return ERR_PTR(err);
 563 }
 564
 565 static int inet_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 566 {
 567         struct in_ifaddr *ifa;
 568
 569         ASSERT_RTNL();
 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(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(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(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(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(ifa->ifa_label, ':');
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         ASSERT_RTNL();
1056
1057         if (!in_dev) {
1058                 if (event == NETDEV_REGISTER) {
1059                         in_dev = inetdev_init(dev);
1060                         if (!in_dev)
1061                                 panic("devinet: Failed to create loopback\n");
1062                         if (dev == &loopback_dev) {
1063                                 in_dev->cnf.no_xfrm = 1;
1064                                 in_dev->cnf.no_policy = 1;
1065                         }
1066                 }
1067                 goto out;
1068         }
1069
1070         switch (event) {
1071         case NETDEV_REGISTER:
1072                 printk(KERN_DEBUG "inetdev_event: bug\n");
1073                 dev->ip_ptr = NULL;
1074                 break;
1075         case NETDEV_UP:
1076                 if (dev->mtu < 68)
1077                         break;
1078                 if (dev == &loopback_dev) {
1079                         struct in_ifaddr *ifa;
1080                         if ((ifa = inet_alloc_ifa()) != NULL) {
1081                                 ifa->ifa_local =
1082                                   ifa->ifa_address = htonl(INADDR_LOOPBACK);
1083                                 ifa->ifa_prefixlen = 8;
1084                                 ifa->ifa_mask = inet_make_mask(8);
1085                                 in_dev_hold(in_dev);
1086                                 ifa->ifa_dev = in_dev;
1087                                 ifa->ifa_scope = RT_SCOPE_HOST;
1088                                 memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
1089                                 inet_insert_ifa(ifa);
1090                         }
1091                 }
1092                 ip_mc_up(in_dev);
1093                 break;
1094         case NETDEV_DOWN:
1095                 ip_mc_down(in_dev);
1096                 break;
1097         case NETDEV_CHANGEMTU:
1098                 if (dev->mtu >= 68)
1099                         break;
1100                 /* MTU falled under 68, disable IP */
1101         case NETDEV_UNREGISTER:
1102                 inetdev_destroy(in_dev);
1103                 break;
1104         case NETDEV_CHANGENAME:
1105                 /* Do not notify about label change, this event is
1106                  * not interesting to applications using netlink.
1107                  */
1108                 inetdev_changename(dev, in_dev);
1109
1110 #ifdef CONFIG_SYSCTL
1111                 devinet_sysctl_unregister(&in_dev->cnf);
1112                 neigh_sysctl_unregister(in_dev->arp_parms);
1113                 neigh_sysctl_register(dev, in_dev->arp_parms, NET_IPV4,
1114                                       NET_IPV4_NEIGH, "ipv4", NULL, NULL);
1115                 devinet_sysctl_register(in_dev, &in_dev->cnf);
1116 #endif
1117                 break;
1118         }
1119 out:
1120         return NOTIFY_DONE;
1121 }
1122
1123 static struct notifier_block ip_netdev_notifier = {
1124         .notifier_call =inetdev_event,
1125 };
1126
1127 static inline size_t inet_nlmsg_size(void)
1128 {
1129         return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
1130                + nla_total_size(4) /* IFA_ADDRESS */
1131                + nla_total_size(4) /* IFA_LOCAL */
1132                + nla_total_size(4) /* IFA_BROADCAST */
1133                + nla_total_size(4) /* IFA_ANYCAST */
1134                + nla_total_size(IFNAMSIZ); /* IFA_LABEL */
1135 }
1136
1137 static int inet_fill_ifaddr(struct sk_buff *skb, struct in_ifaddr *ifa,
1138                             u32 pid, u32 seq, int event, unsigned int flags)
1139 {
1140         struct ifaddrmsg *ifm;
1141         struct nlmsghdr  *nlh;
1142
1143         nlh = nlmsg_put(skb, pid, seq, event, sizeof(*ifm), flags);
1144         if (nlh == NULL)
1145                 return -EMSGSIZE;
1146
1147         ifm = nlmsg_data(nlh);
1148         ifm->ifa_family = AF_INET;
1149         ifm->ifa_prefixlen = ifa->ifa_prefixlen;
1150         ifm->ifa_flags = ifa->ifa_flags|IFA_F_PERMANENT;
1151         ifm->ifa_scope = ifa->ifa_scope;
1152         ifm->ifa_index = ifa->ifa_dev->dev->ifindex;
1153
1154         if (ifa->ifa_address)
1155                 NLA_PUT_BE32(skb, IFA_ADDRESS, ifa->ifa_address);
1156
1157         if (ifa->ifa_local)
1158                 NLA_PUT_BE32(skb, IFA_LOCAL, ifa->ifa_local);
1159
1160         if (ifa->ifa_broadcast)
1161                 NLA_PUT_BE32(skb, IFA_BROADCAST, ifa->ifa_broadcast);
1162
1163         if (ifa->ifa_anycast)
1164                 NLA_PUT_BE32(skb, IFA_ANYCAST, ifa->ifa_anycast);
1165
1166         if (ifa->ifa_label[0])
1167                 NLA_PUT_STRING(skb, IFA_LABEL, ifa->ifa_label);
1168
1169         return nlmsg_end(skb, nlh);
1170
1171 nla_put_failure:
1172         nlmsg_cancel(skb, nlh);
1173         return -EMSGSIZE;
1174 }
1175
1176 static int inet_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
1177 {
1178         int idx, ip_idx;
1179         struct net_device *dev;
1180         struct in_device *in_dev;
1181         struct in_ifaddr *ifa;
1182         int s_ip_idx, s_idx = cb->args[0];
1183
1184         s_ip_idx = ip_idx = cb->args[1];
1185         idx = 0;
1186         for_each_netdev(dev) {
1187                 if (idx < s_idx)
1188                         goto cont;
1189                 if (idx > s_idx)
1190                         s_ip_idx = 0;
1191                 if ((in_dev = __in_dev_get_rtnl(dev)) == NULL)
1192                         goto cont;
1193
1194                 for (ifa = in_dev->ifa_list, ip_idx = 0; ifa;
1195                      ifa = ifa->ifa_next, ip_idx++) {
1196                         if (ip_idx < s_ip_idx)
1197                                 goto cont;
1198                         if (inet_fill_ifaddr(skb, ifa, NETLINK_CB(cb->skb).pid,
1199                                              cb->nlh->nlmsg_seq,
1200                                              RTM_NEWADDR, NLM_F_MULTI) <= 0)
1201                                 goto done;
1202                 }
1203 cont:
1204                 idx++;
1205         }
1206
1207 done:
1208         cb->args[0] = idx;
1209         cb->args[1] = ip_idx;
1210
1211         return skb->len;
1212 }
1213
1214 static void rtmsg_ifa(int event, struct in_ifaddr* ifa, struct nlmsghdr *nlh,
1215                       u32 pid)
1216 {
1217         struct sk_buff *skb;
1218         u32 seq = nlh ? nlh->nlmsg_seq : 0;
1219         int err = -ENOBUFS;
1220
1221         skb = nlmsg_new(inet_nlmsg_size(), GFP_KERNEL);
1222         if (skb == NULL)
1223                 goto errout;
1224
1225         err = inet_fill_ifaddr(skb, ifa, pid, seq, event, 0);
1226         if (err < 0) {
1227                 /* -EMSGSIZE implies BUG in inet_nlmsg_size() */
1228                 WARN_ON(err == -EMSGSIZE);
1229                 kfree_skb(skb);
1230                 goto errout;
1231         }
1232         err = rtnl_notify(skb, pid, RTNLGRP_IPV4_IFADDR, nlh, GFP_KERNEL);
1233 errout:
1234         if (err < 0)
1235                 rtnl_set_sk_err(RTNLGRP_IPV4_IFADDR, err);
1236 }
1237
1238 #ifdef CONFIG_SYSCTL
1239
1240 void inet_forward_change(void)
1241 {
1242         struct net_device *dev;
1243         int on = ipv4_devconf.forwarding;
1244
1245         ipv4_devconf.accept_redirects = !on;
1246         ipv4_devconf_dflt.forwarding = on;
1247
1248         read_lock(&dev_base_lock);
1249         for_each_netdev(dev) {
1250                 struct in_device *in_dev;
1251                 rcu_read_lock();
1252                 in_dev = __in_dev_get_rcu(dev);
1253                 if (in_dev)
1254                         in_dev->cnf.forwarding = on;
1255                 rcu_read_unlock();
1256         }
1257         read_unlock(&dev_base_lock);
1258
1259         rt_cache_flush(0);
1260 }
1261
1262 static int devinet_sysctl_forward(ctl_table *ctl, int write,
1263                                   struct file* filp, void __user *buffer,
1264                                   size_t *lenp, loff_t *ppos)
1265 {
1266         int *valp = ctl->data;
1267         int val = *valp;
1268         int ret = proc_dointvec(ctl, write, filp, buffer, lenp, ppos);
1269
1270         if (write && *valp != val) {
1271                 if (valp == &ipv4_devconf.forwarding)
1272                         inet_forward_change();
1273                 else if (valp != &ipv4_devconf_dflt.forwarding)
1274                         rt_cache_flush(0);
1275         }
1276
1277         return ret;
1278 }
1279
1280 int ipv4_doint_and_flush(ctl_table *ctl, int write,
1281                          struct file* filp, void __user *buffer,
1282                          size_t *lenp, loff_t *ppos)
1283 {
1284         int *valp = ctl->data;
1285         int val = *valp;
1286         int ret = proc_dointvec(ctl, write, filp, buffer, lenp, ppos);
1287
1288         if (write && *valp != val)
1289                 rt_cache_flush(0);
1290
1291         return ret;
1292 }
1293
1294 int ipv4_doint_and_flush_strategy(ctl_table *table, int __user *name, int nlen,
1295                                   void __user *oldval, size_t __user *oldlenp,
1296                                   void __user *newval, size_t newlen)
1297 {
1298         int *valp = table->data;
1299         int new;
1300
1301         if (!newval || !newlen)
1302                 return 0;
1303
1304         if (newlen != sizeof(int))
1305                 return -EINVAL;
1306
1307         if (get_user(new, (int __user *)newval))
1308                 return -EFAULT;
1309
1310         if (new == *valp)
1311                 return 0;
1312
1313         if (oldval && oldlenp) {
1314                 size_t len;
1315
1316                 if (get_user(len, oldlenp))
1317                         return -EFAULT;
1318
1319                 if (len) {
1320                         if (len > table->maxlen)
1321                                 len = table->maxlen;
1322                         if (copy_to_user(oldval, valp, len))
1323                                 return -EFAULT;
1324                         if (put_user(len, oldlenp))
1325                                 return -EFAULT;
1326                 }
1327         }
1328
1329         *valp = new;
1330         rt_cache_flush(0);
1331         return 1;
1332 }
1333
1334
1335 static struct devinet_sysctl_table {
1336         struct ctl_table_header *sysctl_header;
1337         ctl_table               devinet_vars[__NET_IPV4_CONF_MAX];
1338         ctl_table               devinet_dev[2];
1339         ctl_table               devinet_conf_dir[2];
1340         ctl_table               devinet_proto_dir[2];
1341         ctl_table               devinet_root_dir[2];
1342 } devinet_sysctl = {
1343         .devinet_vars = {
1344                 {
1345                         .ctl_name       = NET_IPV4_CONF_FORWARDING,
1346                         .procname       = "forwarding",
1347                         .data           = &ipv4_devconf.forwarding,
1348                         .maxlen         = sizeof(int),
1349                         .mode           = 0644,
1350                         .proc_handler   = &devinet_sysctl_forward,
1351                 },
1352                 {
1353                         .ctl_name       = NET_IPV4_CONF_MC_FORWARDING,
1354                         .procname       = "mc_forwarding",
1355                         .data           = &ipv4_devconf.mc_forwarding,
1356                         .maxlen         = sizeof(int),
1357                         .mode           = 0444,
1358                         .proc_handler   = &proc_dointvec,
1359                 },
1360                 {
1361                         .ctl_name       = NET_IPV4_CONF_ACCEPT_REDIRECTS,
1362                         .procname       = "accept_redirects",
1363                         .data           = &ipv4_devconf.accept_redirects,
1364                         .maxlen         = sizeof(int),
1365                         .mode           = 0644,
1366                         .proc_handler   = &proc_dointvec,
1367                 },
1368                 {
1369                         .ctl_name       = NET_IPV4_CONF_SECURE_REDIRECTS,
1370                         .procname       = "secure_redirects",
1371                         .data           = &ipv4_devconf.secure_redirects,
1372                         .maxlen         = sizeof(int),
1373                         .mode           = 0644,
1374                         .proc_handler   = &proc_dointvec,
1375                 },
1376                 {
1377                         .ctl_name       = NET_IPV4_CONF_SHARED_MEDIA,
1378                         .procname       = "shared_media",
1379                         .data           = &ipv4_devconf.shared_media,
1380                         .maxlen         = sizeof(int),
1381                         .mode           = 0644,
1382                         .proc_handler   = &proc_dointvec,
1383                 },
1384                 {
1385                         .ctl_name       = NET_IPV4_CONF_RP_FILTER,
1386                         .procname       = "rp_filter",
1387                         .data           = &ipv4_devconf.rp_filter,
1388                         .maxlen         = sizeof(int),
1389                         .mode           = 0644,
1390                         .proc_handler   = &proc_dointvec,
1391                 },
1392                 {
1393                         .ctl_name       = NET_IPV4_CONF_SEND_REDIRECTS,
1394                         .procname       = "send_redirects",
1395                         .data           = &ipv4_devconf.send_redirects,
1396                         .maxlen         = sizeof(int),
1397                         .mode           = 0644,
1398                         .proc_handler   = &proc_dointvec,
1399                 },
1400                 {
1401                         .ctl_name       = NET_IPV4_CONF_ACCEPT_SOURCE_ROUTE,
1402                         .procname       = "accept_source_route",
1403                         .data           = &ipv4_devconf.accept_source_route,
1404                         .maxlen         = sizeof(int),
1405                         .mode           = 0644,
1406                         .proc_handler   = &proc_dointvec,
1407                 },
1408                 {
1409                         .ctl_name       = NET_IPV4_CONF_PROXY_ARP,
1410                         .procname       = "proxy_arp",
1411                         .data           = &ipv4_devconf.proxy_arp,
1412                         .maxlen         = sizeof(int),
1413                         .mode           = 0644,
1414                         .proc_handler   = &proc_dointvec,
1415                 },
1416                 {
1417                         .ctl_name       = NET_IPV4_CONF_MEDIUM_ID,
1418                         .procname       = "medium_id",
1419                         .data           = &ipv4_devconf.medium_id,
1420                         .maxlen         = sizeof(int),
1421                         .mode           = 0644,
1422                         .proc_handler   = &proc_dointvec,
1423                 },
1424                 {
1425                         .ctl_name       = NET_IPV4_CONF_BOOTP_RELAY,
1426                         .procname       = "bootp_relay",
1427                         .data           = &ipv4_devconf.bootp_relay,
1428                         .maxlen         = sizeof(int),
1429                         .mode           = 0644,
1430                         .proc_handler   = &proc_dointvec,
1431                 },
1432                 {
1433                         .ctl_name       = NET_IPV4_CONF_LOG_MARTIANS,
1434                         .procname       = "log_martians",
1435                         .data           = &ipv4_devconf.log_martians,
1436                         .maxlen         = sizeof(int),
1437                         .mode           = 0644,
1438                         .proc_handler   = &proc_dointvec,
1439                 },
1440                 {
1441                         .ctl_name       = NET_IPV4_CONF_TAG,
1442                         .procname       = "tag",
1443                         .data           = &ipv4_devconf.tag,
1444                         .maxlen         = sizeof(int),
1445                         .mode           = 0644,
1446                         .proc_handler   = &proc_dointvec,
1447                 },
1448                 {
1449                         .ctl_name       = NET_IPV4_CONF_ARPFILTER,
1450                         .procname       = "arp_filter",
1451                         .data           = &ipv4_devconf.arp_filter,
1452                         .maxlen         = sizeof(int),
1453                         .mode           = 0644,
1454                         .proc_handler   = &proc_dointvec,
1455                 },
1456                 {
1457                         .ctl_name       = NET_IPV4_CONF_ARP_ANNOUNCE,
1458                         .procname       = "arp_announce",
1459                         .data           = &ipv4_devconf.arp_announce,
1460                         .maxlen         = sizeof(int),
1461                         .mode           = 0644,
1462                         .proc_handler   = &proc_dointvec,
1463                 },
1464                 {
1465                         .ctl_name       = NET_IPV4_CONF_ARP_IGNORE,
1466                         .procname       = "arp_ignore",
1467                         .data           = &ipv4_devconf.arp_ignore,
1468                         .maxlen         = sizeof(int),
1469                         .mode           = 0644,
1470                         .proc_handler   = &proc_dointvec,
1471                 },
1472                 {
1473                         .ctl_name       = NET_IPV4_CONF_ARP_ACCEPT,
1474                         .procname       = "arp_accept",
1475                         .data           = &ipv4_devconf.arp_accept,
1476                         .maxlen         = sizeof(int),
1477                         .mode           = 0644,
1478                         .proc_handler   = &proc_dointvec,
1479                 },
1480                 {
1481                         .ctl_name       = NET_IPV4_CONF_NOXFRM,
1482                         .procname       = "disable_xfrm",
1483                         .data           = &ipv4_devconf.no_xfrm,
1484                         .maxlen         = sizeof(int),
1485                         .mode           = 0644,
1486                         .proc_handler   = &ipv4_doint_and_flush,
1487                         .strategy       = &ipv4_doint_and_flush_strategy,
1488                 },
1489                 {
1490                         .ctl_name       = NET_IPV4_CONF_NOPOLICY,
1491                         .procname       = "disable_policy",
1492                         .data           = &ipv4_devconf.no_policy,
1493                         .maxlen         = sizeof(int),
1494                         .mode           = 0644,
1495                         .proc_handler   = &ipv4_doint_and_flush,
1496                         .strategy       = &ipv4_doint_and_flush_strategy,
1497                 },
1498                 {
1499                         .ctl_name       = NET_IPV4_CONF_FORCE_IGMP_VERSION,
1500                         .procname       = "force_igmp_version",
1501                         .data           = &ipv4_devconf.force_igmp_version,
1502                         .maxlen         = sizeof(int),
1503                         .mode           = 0644,
1504                         .proc_handler   = &ipv4_doint_and_flush,
1505                         .strategy       = &ipv4_doint_and_flush_strategy,
1506                 },
1507                 {
1508                         .ctl_name       = NET_IPV4_CONF_PROMOTE_SECONDARIES,
1509                         .procname       = "promote_secondaries",
1510                         .data           = &ipv4_devconf.promote_secondaries,
1511                         .maxlen         = sizeof(int),
1512                         .mode           = 0644,
1513                         .proc_handler   = &ipv4_doint_and_flush,
1514                         .strategy       = &ipv4_doint_and_flush_strategy,
1515                 },
1516         },
1517         .devinet_dev = {
1518                 {
1519                         .ctl_name       = NET_PROTO_CONF_ALL,
1520                         .procname       = "all",
1521                         .mode           = 0555,
1522                         .child          = devinet_sysctl.devinet_vars,
1523                 },
1524         },
1525         .devinet_conf_dir = {
1526                 {
1527                         .ctl_name       = NET_IPV4_CONF,
1528                         .procname       = "conf",
1529                         .mode           = 0555,
1530                         .child          = devinet_sysctl.devinet_dev,
1531                 },
1532         },
1533         .devinet_proto_dir = {
1534                 {
1535                         .ctl_name       = NET_IPV4,
1536                         .procname       = "ipv4",
1537                         .mode           = 0555,
1538                         .child          = devinet_sysctl.devinet_conf_dir,
1539                 },
1540         },
1541         .devinet_root_dir = {
1542                 {
1543                         .ctl_name       = CTL_NET,
1544                         .procname       = "net",
1545                         .mode           = 0555,
1546                         .child          = devinet_sysctl.devinet_proto_dir,
1547                 },
1548         },
1549 };
1550
1551 static void devinet_sysctl_register(struct in_device *in_dev,
1552                                     struct ipv4_devconf *p)
1553 {
1554         int i;
1555         struct net_device *dev = in_dev ? in_dev->dev : NULL;
1556         struct devinet_sysctl_table *t = kmemdup(&devinet_sysctl, sizeof(*t),
1557                                                  GFP_KERNEL);
1558         char *dev_name = NULL;
1559
1560         if (!t)
1561                 return;
1562         for (i = 0; i < ARRAY_SIZE(t->devinet_vars) - 1; i++) {
1563                 t->devinet_vars[i].data += (char *)p - (char *)&ipv4_devconf;
1564         }
1565
1566         if (dev) {
1567                 dev_name = dev->name;
1568                 t->devinet_dev[0].ctl_name = dev->ifindex;
1569         } else {
1570                 dev_name = "default";
1571                 t->devinet_dev[0].ctl_name = NET_PROTO_CONF_DEFAULT;
1572         }
1573
1574         /*
1575          * Make a copy of dev_name, because '.procname' is regarded as const
1576          * by sysctl and we wouldn't want anyone to change it under our feet
1577          * (see SIOCSIFNAME).
1578          */
1579         dev_name = kstrdup(dev_name, GFP_KERNEL);
1580         if (!dev_name)
1581             goto free;
1582
1583         t->devinet_dev[0].procname    = dev_name;
1584         t->devinet_dev[0].child       = t->devinet_vars;
1585         t->devinet_conf_dir[0].child  = t->devinet_dev;
1586         t->devinet_proto_dir[0].child = t->devinet_conf_dir;
1587         t->devinet_root_dir[0].child  = t->devinet_proto_dir;
1588
1589         t->sysctl_header = register_sysctl_table(t->devinet_root_dir);
1590         if (!t->sysctl_header)
1591             goto free_procname;
1592
1593         p->sysctl = t;
1594         return;
1595
1596         /* error path */
1597  free_procname:
1598         kfree(dev_name);
1599  free:
1600         kfree(t);
1601         return;
1602 }
1603
1604 static void devinet_sysctl_unregister(struct ipv4_devconf *p)
1605 {
1606         if (p->sysctl) {
1607                 struct devinet_sysctl_table *t = p->sysctl;
1608                 p->sysctl = NULL;
1609                 unregister_sysctl_table(t->sysctl_header);
1610                 kfree(t->devinet_dev[0].procname);
1611                 kfree(t);
1612         }
1613 }
1614 #endif
1615
1616 void __init devinet_init(void)
1617 {
1618         register_gifconf(PF_INET, inet_gifconf);
1619         register_netdevice_notifier(&ip_netdev_notifier);
1620
1621         rtnl_register(PF_INET, RTM_NEWADDR, inet_rtm_newaddr, NULL);
1622         rtnl_register(PF_INET, RTM_DELADDR, inet_rtm_deladdr, NULL);
1623         rtnl_register(PF_INET, RTM_GETADDR, NULL, inet_dump_ifaddr);
1624 #ifdef CONFIG_SYSCTL
1625         devinet_sysctl.sysctl_header =
1626                 register_sysctl_table(devinet_sysctl.devinet_root_dir);
1627         devinet_sysctl_register(NULL, &ipv4_devconf_dflt);
1628 #endif
1629 }
1630
1631 EXPORT_SYMBOL(in_dev_finish_destroy);
1632 EXPORT_SYMBOL(inet_select_addr);
1633 EXPORT_SYMBOL(inetdev_by_index);
1634 EXPORT_SYMBOL(register_inetaddr_notifier);
1635 EXPORT_SYMBOL(unregister_inetaddr_notifier);