devinet.c revision 7c89943236750537d26421d9bbb6f6575e2d1e1b
1/* 2 * NET3 IP device support routines. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public License 6 * as published by the Free Software Foundation; either version 7 * 2 of the License, or (at your option) any later version. 8 * 9 * Derived from the IP parts of dev.c 1.0.19 10 * Authors: Ross Biro 11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> 12 * Mark Evans, <evansmp@uhura.aston.ac.uk> 13 * 14 * Additional Authors: 15 * Alan Cox, <gw4pts@gw4pts.ampr.org> 16 * Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> 17 * 18 * Changes: 19 * Alexey Kuznetsov: pa_* fields are replaced with ifaddr 20 * lists. 21 * Cyrus Durgin: updated for kmod 22 * Matthias Andree: in devinet_ioctl, compare label and 23 * address (4.4BSD alias style support), 24 * fall back to comparing just the label 25 * if no match found. 26 */ 27 28 29#include <asm/uaccess.h> 30#include <asm/system.h> 31#include <linux/bitops.h> 32#include <linux/capability.h> 33#include <linux/module.h> 34#include <linux/types.h> 35#include <linux/kernel.h> 36#include <linux/string.h> 37#include <linux/mm.h> 38#include <linux/socket.h> 39#include <linux/sockios.h> 40#include <linux/in.h> 41#include <linux/errno.h> 42#include <linux/interrupt.h> 43#include <linux/if_addr.h> 44#include <linux/if_ether.h> 45#include <linux/inet.h> 46#include <linux/netdevice.h> 47#include <linux/etherdevice.h> 48#include <linux/skbuff.h> 49#include <linux/init.h> 50#include <linux/notifier.h> 51#include <linux/inetdevice.h> 52#include <linux/igmp.h> 53#include <linux/slab.h> 54#include <linux/hash.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#include "fib_lookup.h" 68 69static struct ipv4_devconf ipv4_devconf = { 70 .data = { 71 [IPV4_DEVCONF_ACCEPT_REDIRECTS - 1] = 1, 72 [IPV4_DEVCONF_SEND_REDIRECTS - 1] = 1, 73 [IPV4_DEVCONF_SECURE_REDIRECTS - 1] = 1, 74 [IPV4_DEVCONF_SHARED_MEDIA - 1] = 1, 75 }, 76}; 77 78static struct ipv4_devconf ipv4_devconf_dflt = { 79 .data = { 80 [IPV4_DEVCONF_ACCEPT_REDIRECTS - 1] = 1, 81 [IPV4_DEVCONF_SEND_REDIRECTS - 1] = 1, 82 [IPV4_DEVCONF_SECURE_REDIRECTS - 1] = 1, 83 [IPV4_DEVCONF_SHARED_MEDIA - 1] = 1, 84 [IPV4_DEVCONF_ACCEPT_SOURCE_ROUTE - 1] = 1, 85 }, 86}; 87 88#define IPV4_DEVCONF_DFLT(net, attr) \ 89 IPV4_DEVCONF((*net->ipv4.devconf_dflt), attr) 90 91static const struct nla_policy ifa_ipv4_policy[IFA_MAX+1] = { 92 [IFA_LOCAL] = { .type = NLA_U32 }, 93 [IFA_ADDRESS] = { .type = NLA_U32 }, 94 [IFA_BROADCAST] = { .type = NLA_U32 }, 95 [IFA_LABEL] = { .type = NLA_STRING, .len = IFNAMSIZ - 1 }, 96}; 97 98/* inet_addr_hash's shifting is dependent upon this IN4_ADDR_HSIZE 99 * value. So if you change this define, make appropriate changes to 100 * inet_addr_hash as well. 101 */ 102#define IN4_ADDR_HSIZE 256 103static struct hlist_head inet_addr_lst[IN4_ADDR_HSIZE]; 104static DEFINE_SPINLOCK(inet_addr_hash_lock); 105 106static inline unsigned int inet_addr_hash(struct net *net, __be32 addr) 107{ 108 u32 val = (__force u32) addr ^ hash_ptr(net, 8); 109 110 return ((val ^ (val >> 8) ^ (val >> 16) ^ (val >> 24)) & 111 (IN4_ADDR_HSIZE - 1)); 112} 113 114static void inet_hash_insert(struct net *net, struct in_ifaddr *ifa) 115{ 116 unsigned int hash = inet_addr_hash(net, ifa->ifa_local); 117 118 spin_lock(&inet_addr_hash_lock); 119 hlist_add_head_rcu(&ifa->hash, &inet_addr_lst[hash]); 120 spin_unlock(&inet_addr_hash_lock); 121} 122 123static void inet_hash_remove(struct in_ifaddr *ifa) 124{ 125 spin_lock(&inet_addr_hash_lock); 126 hlist_del_init_rcu(&ifa->hash); 127 spin_unlock(&inet_addr_hash_lock); 128} 129 130/** 131 * __ip_dev_find - find the first device with a given source address. 132 * @net: the net namespace 133 * @addr: the source address 134 * @devref: if true, take a reference on the found device 135 * 136 * If a caller uses devref=false, it should be protected by RCU, or RTNL 137 */ 138struct net_device *__ip_dev_find(struct net *net, __be32 addr, bool devref) 139{ 140 unsigned int hash = inet_addr_hash(net, addr); 141 struct net_device *result = NULL; 142 struct in_ifaddr *ifa; 143 struct hlist_node *node; 144 145 rcu_read_lock(); 146 hlist_for_each_entry_rcu(ifa, node, &inet_addr_lst[hash], hash) { 147 struct net_device *dev = ifa->ifa_dev->dev; 148 149 if (!net_eq(dev_net(dev), net)) 150 continue; 151 if (ifa->ifa_local == addr) { 152 result = dev; 153 break; 154 } 155 } 156 if (!result) { 157 struct flowi4 fl4 = { .daddr = addr }; 158 struct fib_result res = { 0 }; 159 struct fib_table *local; 160 161 /* Fallback to FIB local table so that communication 162 * over loopback subnets work. 163 */ 164 local = fib_get_table(net, RT_TABLE_LOCAL); 165 if (local && 166 !fib_table_lookup(local, &fl4, &res, FIB_LOOKUP_NOREF) && 167 res.type == RTN_LOCAL) 168 result = FIB_RES_DEV(res); 169 } 170 if (result && devref) 171 dev_hold(result); 172 rcu_read_unlock(); 173 return result; 174} 175EXPORT_SYMBOL(__ip_dev_find); 176 177static void rtmsg_ifa(int event, struct in_ifaddr *, struct nlmsghdr *, u32); 178 179static BLOCKING_NOTIFIER_HEAD(inetaddr_chain); 180static void inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap, 181 int destroy); 182#ifdef CONFIG_SYSCTL 183static void devinet_sysctl_register(struct in_device *idev); 184static void devinet_sysctl_unregister(struct in_device *idev); 185#else 186static inline void devinet_sysctl_register(struct in_device *idev) 187{ 188} 189static inline void devinet_sysctl_unregister(struct in_device *idev) 190{ 191} 192#endif 193 194/* Locks all the inet devices. */ 195 196static struct in_ifaddr *inet_alloc_ifa(void) 197{ 198 return kzalloc(sizeof(struct in_ifaddr), GFP_KERNEL); 199} 200 201static void inet_rcu_free_ifa(struct rcu_head *head) 202{ 203 struct in_ifaddr *ifa = container_of(head, struct in_ifaddr, rcu_head); 204 if (ifa->ifa_dev) 205 in_dev_put(ifa->ifa_dev); 206 kfree(ifa); 207} 208 209static inline void inet_free_ifa(struct in_ifaddr *ifa) 210{ 211 call_rcu(&ifa->rcu_head, inet_rcu_free_ifa); 212} 213 214void in_dev_finish_destroy(struct in_device *idev) 215{ 216 struct net_device *dev = idev->dev; 217 218 WARN_ON(idev->ifa_list); 219 WARN_ON(idev->mc_list); 220#ifdef NET_REFCNT_DEBUG 221 printk(KERN_DEBUG "in_dev_finish_destroy: %p=%s\n", 222 idev, dev ? dev->name : "NIL"); 223#endif 224 dev_put(dev); 225 if (!idev->dead) 226 pr_err("Freeing alive in_device %p\n", idev); 227 else 228 kfree(idev); 229} 230EXPORT_SYMBOL(in_dev_finish_destroy); 231 232static struct in_device *inetdev_init(struct net_device *dev) 233{ 234 struct in_device *in_dev; 235 236 ASSERT_RTNL(); 237 238 in_dev = kzalloc(sizeof(*in_dev), GFP_KERNEL); 239 if (!in_dev) 240 goto out; 241 memcpy(&in_dev->cnf, dev_net(dev)->ipv4.devconf_dflt, 242 sizeof(in_dev->cnf)); 243 in_dev->cnf.sysctl = NULL; 244 in_dev->dev = dev; 245 in_dev->arp_parms = neigh_parms_alloc(dev, &arp_tbl); 246 if (!in_dev->arp_parms) 247 goto out_kfree; 248 if (IPV4_DEVCONF(in_dev->cnf, FORWARDING)) 249 dev_disable_lro(dev); 250 /* Reference in_dev->dev */ 251 dev_hold(dev); 252 /* Account for reference dev->ip_ptr (below) */ 253 in_dev_hold(in_dev); 254 255 devinet_sysctl_register(in_dev); 256 ip_mc_init_dev(in_dev); 257 if (dev->flags & IFF_UP) 258 ip_mc_up(in_dev); 259 260 /* we can receive as soon as ip_ptr is set -- do this last */ 261 rcu_assign_pointer(dev->ip_ptr, in_dev); 262out: 263 return in_dev; 264out_kfree: 265 kfree(in_dev); 266 in_dev = NULL; 267 goto out; 268} 269 270static void in_dev_rcu_put(struct rcu_head *head) 271{ 272 struct in_device *idev = container_of(head, struct in_device, rcu_head); 273 in_dev_put(idev); 274} 275 276static void inetdev_destroy(struct in_device *in_dev) 277{ 278 struct in_ifaddr *ifa; 279 struct net_device *dev; 280 281 ASSERT_RTNL(); 282 283 dev = in_dev->dev; 284 285 in_dev->dead = 1; 286 287 ip_mc_destroy_dev(in_dev); 288 289 while ((ifa = in_dev->ifa_list) != NULL) { 290 inet_del_ifa(in_dev, &in_dev->ifa_list, 0); 291 inet_free_ifa(ifa); 292 } 293 294 rcu_assign_pointer(dev->ip_ptr, NULL); 295 296 devinet_sysctl_unregister(in_dev); 297 neigh_parms_release(&arp_tbl, in_dev->arp_parms); 298 arp_ifdown(dev); 299 300 call_rcu(&in_dev->rcu_head, in_dev_rcu_put); 301} 302 303int inet_addr_onlink(struct in_device *in_dev, __be32 a, __be32 b) 304{ 305 rcu_read_lock(); 306 for_primary_ifa(in_dev) { 307 if (inet_ifa_match(a, ifa)) { 308 if (!b || inet_ifa_match(b, ifa)) { 309 rcu_read_unlock(); 310 return 1; 311 } 312 } 313 } endfor_ifa(in_dev); 314 rcu_read_unlock(); 315 return 0; 316} 317 318static void __inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap, 319 int destroy, struct nlmsghdr *nlh, u32 pid) 320{ 321 struct in_ifaddr *promote = NULL; 322 struct in_ifaddr *ifa, *ifa1 = *ifap; 323 struct in_ifaddr *last_prim = in_dev->ifa_list; 324 struct in_ifaddr *prev_prom = NULL; 325 int do_promote = IN_DEV_PROMOTE_SECONDARIES(in_dev); 326 327 ASSERT_RTNL(); 328 329 /* 1. Deleting primary ifaddr forces deletion all secondaries 330 * unless alias promotion is set 331 **/ 332 333 if (!(ifa1->ifa_flags & IFA_F_SECONDARY)) { 334 struct in_ifaddr **ifap1 = &ifa1->ifa_next; 335 336 while ((ifa = *ifap1) != NULL) { 337 if (!(ifa->ifa_flags & IFA_F_SECONDARY) && 338 ifa1->ifa_scope <= ifa->ifa_scope) 339 last_prim = ifa; 340 341 if (!(ifa->ifa_flags & IFA_F_SECONDARY) || 342 ifa1->ifa_mask != ifa->ifa_mask || 343 !inet_ifa_match(ifa1->ifa_address, ifa)) { 344 ifap1 = &ifa->ifa_next; 345 prev_prom = ifa; 346 continue; 347 } 348 349 if (!do_promote) { 350 inet_hash_remove(ifa); 351 *ifap1 = ifa->ifa_next; 352 353 rtmsg_ifa(RTM_DELADDR, ifa, nlh, pid); 354 blocking_notifier_call_chain(&inetaddr_chain, 355 NETDEV_DOWN, ifa); 356 inet_free_ifa(ifa); 357 } else { 358 promote = ifa; 359 break; 360 } 361 } 362 } 363 364 /* On promotion all secondaries from subnet are changing 365 * the primary IP, we must remove all their routes silently 366 * and later to add them back with new prefsrc. Do this 367 * while all addresses are on the device list. 368 */ 369 for (ifa = promote; ifa; ifa = ifa->ifa_next) { 370 if (ifa1->ifa_mask == ifa->ifa_mask && 371 inet_ifa_match(ifa1->ifa_address, ifa)) 372 fib_del_ifaddr(ifa, ifa1); 373 } 374 375 /* 2. Unlink it */ 376 377 *ifap = ifa1->ifa_next; 378 inet_hash_remove(ifa1); 379 380 /* 3. Announce address deletion */ 381 382 /* Send message first, then call notifier. 383 At first sight, FIB update triggered by notifier 384 will refer to already deleted ifaddr, that could confuse 385 netlink listeners. It is not true: look, gated sees 386 that route deleted and if it still thinks that ifaddr 387 is valid, it will try to restore deleted routes... Grr. 388 So that, this order is correct. 389 */ 390 rtmsg_ifa(RTM_DELADDR, ifa1, nlh, pid); 391 blocking_notifier_call_chain(&inetaddr_chain, NETDEV_DOWN, ifa1); 392 393 if (promote) { 394 struct in_ifaddr *next_sec = promote->ifa_next; 395 396 if (prev_prom) { 397 prev_prom->ifa_next = promote->ifa_next; 398 promote->ifa_next = last_prim->ifa_next; 399 last_prim->ifa_next = promote; 400 } 401 402 promote->ifa_flags &= ~IFA_F_SECONDARY; 403 rtmsg_ifa(RTM_NEWADDR, promote, nlh, pid); 404 blocking_notifier_call_chain(&inetaddr_chain, 405 NETDEV_UP, promote); 406 for (ifa = next_sec; ifa; ifa = ifa->ifa_next) { 407 if (ifa1->ifa_mask != ifa->ifa_mask || 408 !inet_ifa_match(ifa1->ifa_address, ifa)) 409 continue; 410 fib_add_ifaddr(ifa); 411 } 412 413 } 414 if (destroy) 415 inet_free_ifa(ifa1); 416} 417 418static void inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap, 419 int destroy) 420{ 421 __inet_del_ifa(in_dev, ifap, destroy, NULL, 0); 422} 423 424static int __inet_insert_ifa(struct in_ifaddr *ifa, struct nlmsghdr *nlh, 425 u32 pid) 426{ 427 struct in_device *in_dev = ifa->ifa_dev; 428 struct in_ifaddr *ifa1, **ifap, **last_primary; 429 430 ASSERT_RTNL(); 431 432 if (!ifa->ifa_local) { 433 inet_free_ifa(ifa); 434 return 0; 435 } 436 437 ifa->ifa_flags &= ~IFA_F_SECONDARY; 438 last_primary = &in_dev->ifa_list; 439 440 for (ifap = &in_dev->ifa_list; (ifa1 = *ifap) != NULL; 441 ifap = &ifa1->ifa_next) { 442 if (!(ifa1->ifa_flags & IFA_F_SECONDARY) && 443 ifa->ifa_scope <= ifa1->ifa_scope) 444 last_primary = &ifa1->ifa_next; 445 if (ifa1->ifa_mask == ifa->ifa_mask && 446 inet_ifa_match(ifa1->ifa_address, ifa)) { 447 if (ifa1->ifa_local == ifa->ifa_local) { 448 inet_free_ifa(ifa); 449 return -EEXIST; 450 } 451 if (ifa1->ifa_scope != ifa->ifa_scope) { 452 inet_free_ifa(ifa); 453 return -EINVAL; 454 } 455 ifa->ifa_flags |= IFA_F_SECONDARY; 456 } 457 } 458 459 if (!(ifa->ifa_flags & IFA_F_SECONDARY)) { 460 net_srandom(ifa->ifa_local); 461 ifap = last_primary; 462 } 463 464 ifa->ifa_next = *ifap; 465 *ifap = ifa; 466 467 inet_hash_insert(dev_net(in_dev->dev), ifa); 468 469 /* Send message first, then call notifier. 470 Notifier will trigger FIB update, so that 471 listeners of netlink will know about new ifaddr */ 472 rtmsg_ifa(RTM_NEWADDR, ifa, nlh, pid); 473 blocking_notifier_call_chain(&inetaddr_chain, NETDEV_UP, ifa); 474 475 return 0; 476} 477 478static int inet_insert_ifa(struct in_ifaddr *ifa) 479{ 480 return __inet_insert_ifa(ifa, NULL, 0); 481} 482 483static int inet_set_ifa(struct net_device *dev, struct in_ifaddr *ifa) 484{ 485 struct in_device *in_dev = __in_dev_get_rtnl(dev); 486 487 ASSERT_RTNL(); 488 489 if (!in_dev) { 490 inet_free_ifa(ifa); 491 return -ENOBUFS; 492 } 493 ipv4_devconf_setall(in_dev); 494 if (ifa->ifa_dev != in_dev) { 495 WARN_ON(ifa->ifa_dev); 496 in_dev_hold(in_dev); 497 ifa->ifa_dev = in_dev; 498 } 499 if (ipv4_is_loopback(ifa->ifa_local)) 500 ifa->ifa_scope = RT_SCOPE_HOST; 501 return inet_insert_ifa(ifa); 502} 503 504/* Caller must hold RCU or RTNL : 505 * We dont take a reference on found in_device 506 */ 507struct in_device *inetdev_by_index(struct net *net, int ifindex) 508{ 509 struct net_device *dev; 510 struct in_device *in_dev = NULL; 511 512 rcu_read_lock(); 513 dev = dev_get_by_index_rcu(net, ifindex); 514 if (dev) 515 in_dev = rcu_dereference_rtnl(dev->ip_ptr); 516 rcu_read_unlock(); 517 return in_dev; 518} 519EXPORT_SYMBOL(inetdev_by_index); 520 521/* Called only from RTNL semaphored context. No locks. */ 522 523struct in_ifaddr *inet_ifa_byprefix(struct in_device *in_dev, __be32 prefix, 524 __be32 mask) 525{ 526 ASSERT_RTNL(); 527 528 for_primary_ifa(in_dev) { 529 if (ifa->ifa_mask == mask && inet_ifa_match(prefix, ifa)) 530 return ifa; 531 } endfor_ifa(in_dev); 532 return NULL; 533} 534 535static int inet_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg) 536{ 537 struct net *net = sock_net(skb->sk); 538 struct nlattr *tb[IFA_MAX+1]; 539 struct in_device *in_dev; 540 struct ifaddrmsg *ifm; 541 struct in_ifaddr *ifa, **ifap; 542 int err = -EINVAL; 543 544 ASSERT_RTNL(); 545 546 err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv4_policy); 547 if (err < 0) 548 goto errout; 549 550 ifm = nlmsg_data(nlh); 551 in_dev = inetdev_by_index(net, ifm->ifa_index); 552 if (in_dev == NULL) { 553 err = -ENODEV; 554 goto errout; 555 } 556 557 for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL; 558 ifap = &ifa->ifa_next) { 559 if (tb[IFA_LOCAL] && 560 ifa->ifa_local != nla_get_be32(tb[IFA_LOCAL])) 561 continue; 562 563 if (tb[IFA_LABEL] && nla_strcmp(tb[IFA_LABEL], ifa->ifa_label)) 564 continue; 565 566 if (tb[IFA_ADDRESS] && 567 (ifm->ifa_prefixlen != ifa->ifa_prefixlen || 568 !inet_ifa_match(nla_get_be32(tb[IFA_ADDRESS]), ifa))) 569 continue; 570 571 __inet_del_ifa(in_dev, ifap, 1, nlh, NETLINK_CB(skb).pid); 572 return 0; 573 } 574 575 err = -EADDRNOTAVAIL; 576errout: 577 return err; 578} 579 580static struct in_ifaddr *rtm_to_ifaddr(struct net *net, struct nlmsghdr *nlh) 581{ 582 struct nlattr *tb[IFA_MAX+1]; 583 struct in_ifaddr *ifa; 584 struct ifaddrmsg *ifm; 585 struct net_device *dev; 586 struct in_device *in_dev; 587 int err; 588 589 err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv4_policy); 590 if (err < 0) 591 goto errout; 592 593 ifm = nlmsg_data(nlh); 594 err = -EINVAL; 595 if (ifm->ifa_prefixlen > 32 || tb[IFA_LOCAL] == NULL) 596 goto errout; 597 598 dev = __dev_get_by_index(net, ifm->ifa_index); 599 err = -ENODEV; 600 if (dev == NULL) 601 goto errout; 602 603 in_dev = __in_dev_get_rtnl(dev); 604 err = -ENOBUFS; 605 if (in_dev == NULL) 606 goto errout; 607 608 ifa = inet_alloc_ifa(); 609 if (ifa == NULL) 610 /* 611 * A potential indev allocation can be left alive, it stays 612 * assigned to its device and is destroy with it. 613 */ 614 goto errout; 615 616 ipv4_devconf_setall(in_dev); 617 in_dev_hold(in_dev); 618 619 if (tb[IFA_ADDRESS] == NULL) 620 tb[IFA_ADDRESS] = tb[IFA_LOCAL]; 621 622 INIT_HLIST_NODE(&ifa->hash); 623 ifa->ifa_prefixlen = ifm->ifa_prefixlen; 624 ifa->ifa_mask = inet_make_mask(ifm->ifa_prefixlen); 625 ifa->ifa_flags = ifm->ifa_flags; 626 ifa->ifa_scope = ifm->ifa_scope; 627 ifa->ifa_dev = in_dev; 628 629 ifa->ifa_local = nla_get_be32(tb[IFA_LOCAL]); 630 ifa->ifa_address = nla_get_be32(tb[IFA_ADDRESS]); 631 632 if (tb[IFA_BROADCAST]) 633 ifa->ifa_broadcast = nla_get_be32(tb[IFA_BROADCAST]); 634 635 if (tb[IFA_LABEL]) 636 nla_strlcpy(ifa->ifa_label, tb[IFA_LABEL], IFNAMSIZ); 637 else 638 memcpy(ifa->ifa_label, dev->name, IFNAMSIZ); 639 640 return ifa; 641 642errout: 643 return ERR_PTR(err); 644} 645 646static int inet_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg) 647{ 648 struct net *net = sock_net(skb->sk); 649 struct in_ifaddr *ifa; 650 651 ASSERT_RTNL(); 652 653 ifa = rtm_to_ifaddr(net, nlh); 654 if (IS_ERR(ifa)) 655 return PTR_ERR(ifa); 656 657 return __inet_insert_ifa(ifa, nlh, NETLINK_CB(skb).pid); 658} 659 660/* 661 * Determine a default network mask, based on the IP address. 662 */ 663 664static inline int inet_abc_len(__be32 addr) 665{ 666 int rc = -1; /* Something else, probably a multicast. */ 667 668 if (ipv4_is_zeronet(addr)) 669 rc = 0; 670 else { 671 __u32 haddr = ntohl(addr); 672 673 if (IN_CLASSA(haddr)) 674 rc = 8; 675 else if (IN_CLASSB(haddr)) 676 rc = 16; 677 else if (IN_CLASSC(haddr)) 678 rc = 24; 679 } 680 681 return rc; 682} 683 684 685int devinet_ioctl(struct net *net, unsigned int cmd, void __user *arg) 686{ 687 struct ifreq ifr; 688 struct sockaddr_in sin_orig; 689 struct sockaddr_in *sin = (struct sockaddr_in *)&ifr.ifr_addr; 690 struct in_device *in_dev; 691 struct in_ifaddr **ifap = NULL; 692 struct in_ifaddr *ifa = NULL; 693 struct net_device *dev; 694 char *colon; 695 int ret = -EFAULT; 696 int tryaddrmatch = 0; 697 698 /* 699 * Fetch the caller's info block into kernel space 700 */ 701 702 if (copy_from_user(&ifr, arg, sizeof(struct ifreq))) 703 goto out; 704 ifr.ifr_name[IFNAMSIZ - 1] = 0; 705 706 /* save original address for comparison */ 707 memcpy(&sin_orig, sin, sizeof(*sin)); 708 709 colon = strchr(ifr.ifr_name, ':'); 710 if (colon) 711 *colon = 0; 712 713 dev_load(net, ifr.ifr_name); 714 715 switch (cmd) { 716 case SIOCGIFADDR: /* Get interface address */ 717 case SIOCGIFBRDADDR: /* Get the broadcast address */ 718 case SIOCGIFDSTADDR: /* Get the destination address */ 719 case SIOCGIFNETMASK: /* Get the netmask for the interface */ 720 /* Note that these ioctls will not sleep, 721 so that we do not impose a lock. 722 One day we will be forced to put shlock here (I mean SMP) 723 */ 724 tryaddrmatch = (sin_orig.sin_family == AF_INET); 725 memset(sin, 0, sizeof(*sin)); 726 sin->sin_family = AF_INET; 727 break; 728 729 case SIOCSIFFLAGS: 730 ret = -EACCES; 731 if (!capable(CAP_NET_ADMIN)) 732 goto out; 733 break; 734 case SIOCSIFADDR: /* Set interface address (and family) */ 735 case SIOCSIFBRDADDR: /* Set the broadcast address */ 736 case SIOCSIFDSTADDR: /* Set the destination address */ 737 case SIOCSIFNETMASK: /* Set the netmask for the interface */ 738 ret = -EACCES; 739 if (!capable(CAP_NET_ADMIN)) 740 goto out; 741 ret = -EINVAL; 742 if (sin->sin_family != AF_INET) 743 goto out; 744 break; 745 default: 746 ret = -EINVAL; 747 goto out; 748 } 749 750 rtnl_lock(); 751 752 ret = -ENODEV; 753 dev = __dev_get_by_name(net, ifr.ifr_name); 754 if (!dev) 755 goto done; 756 757 if (colon) 758 *colon = ':'; 759 760 in_dev = __in_dev_get_rtnl(dev); 761 if (in_dev) { 762 if (tryaddrmatch) { 763 /* Matthias Andree */ 764 /* compare label and address (4.4BSD style) */ 765 /* note: we only do this for a limited set of ioctls 766 and only if the original address family was AF_INET. 767 This is checked above. */ 768 for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL; 769 ifap = &ifa->ifa_next) { 770 if (!strcmp(ifr.ifr_name, ifa->ifa_label) && 771 sin_orig.sin_addr.s_addr == 772 ifa->ifa_local) { 773 break; /* found */ 774 } 775 } 776 } 777 /* we didn't get a match, maybe the application is 778 4.3BSD-style and passed in junk so we fall back to 779 comparing just the label */ 780 if (!ifa) { 781 for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL; 782 ifap = &ifa->ifa_next) 783 if (!strcmp(ifr.ifr_name, ifa->ifa_label)) 784 break; 785 } 786 } 787 788 ret = -EADDRNOTAVAIL; 789 if (!ifa && cmd != SIOCSIFADDR && cmd != SIOCSIFFLAGS) 790 goto done; 791 792 switch (cmd) { 793 case SIOCGIFADDR: /* Get interface address */ 794 sin->sin_addr.s_addr = ifa->ifa_local; 795 goto rarok; 796 797 case SIOCGIFBRDADDR: /* Get the broadcast address */ 798 sin->sin_addr.s_addr = ifa->ifa_broadcast; 799 goto rarok; 800 801 case SIOCGIFDSTADDR: /* Get the destination address */ 802 sin->sin_addr.s_addr = ifa->ifa_address; 803 goto rarok; 804 805 case SIOCGIFNETMASK: /* Get the netmask for the interface */ 806 sin->sin_addr.s_addr = ifa->ifa_mask; 807 goto rarok; 808 809 case SIOCSIFFLAGS: 810 if (colon) { 811 ret = -EADDRNOTAVAIL; 812 if (!ifa) 813 break; 814 ret = 0; 815 if (!(ifr.ifr_flags & IFF_UP)) 816 inet_del_ifa(in_dev, ifap, 1); 817 break; 818 } 819 ret = dev_change_flags(dev, ifr.ifr_flags); 820 break; 821 822 case SIOCSIFADDR: /* Set interface address (and family) */ 823 ret = -EINVAL; 824 if (inet_abc_len(sin->sin_addr.s_addr) < 0) 825 break; 826 827 if (!ifa) { 828 ret = -ENOBUFS; 829 ifa = inet_alloc_ifa(); 830 INIT_HLIST_NODE(&ifa->hash); 831 if (!ifa) 832 break; 833 if (colon) 834 memcpy(ifa->ifa_label, ifr.ifr_name, IFNAMSIZ); 835 else 836 memcpy(ifa->ifa_label, dev->name, IFNAMSIZ); 837 } else { 838 ret = 0; 839 if (ifa->ifa_local == sin->sin_addr.s_addr) 840 break; 841 inet_del_ifa(in_dev, ifap, 0); 842 ifa->ifa_broadcast = 0; 843 ifa->ifa_scope = 0; 844 } 845 846 ifa->ifa_address = ifa->ifa_local = sin->sin_addr.s_addr; 847 848 if (!(dev->flags & IFF_POINTOPOINT)) { 849 ifa->ifa_prefixlen = inet_abc_len(ifa->ifa_address); 850 ifa->ifa_mask = inet_make_mask(ifa->ifa_prefixlen); 851 if ((dev->flags & IFF_BROADCAST) && 852 ifa->ifa_prefixlen < 31) 853 ifa->ifa_broadcast = ifa->ifa_address | 854 ~ifa->ifa_mask; 855 } else { 856 ifa->ifa_prefixlen = 32; 857 ifa->ifa_mask = inet_make_mask(32); 858 } 859 ret = inet_set_ifa(dev, ifa); 860 break; 861 862 case SIOCSIFBRDADDR: /* Set the broadcast address */ 863 ret = 0; 864 if (ifa->ifa_broadcast != sin->sin_addr.s_addr) { 865 inet_del_ifa(in_dev, ifap, 0); 866 ifa->ifa_broadcast = sin->sin_addr.s_addr; 867 inet_insert_ifa(ifa); 868 } 869 break; 870 871 case SIOCSIFDSTADDR: /* Set the destination address */ 872 ret = 0; 873 if (ifa->ifa_address == sin->sin_addr.s_addr) 874 break; 875 ret = -EINVAL; 876 if (inet_abc_len(sin->sin_addr.s_addr) < 0) 877 break; 878 ret = 0; 879 inet_del_ifa(in_dev, ifap, 0); 880 ifa->ifa_address = sin->sin_addr.s_addr; 881 inet_insert_ifa(ifa); 882 break; 883 884 case SIOCSIFNETMASK: /* Set the netmask for the interface */ 885 886 /* 887 * The mask we set must be legal. 888 */ 889 ret = -EINVAL; 890 if (bad_mask(sin->sin_addr.s_addr, 0)) 891 break; 892 ret = 0; 893 if (ifa->ifa_mask != sin->sin_addr.s_addr) { 894 __be32 old_mask = ifa->ifa_mask; 895 inet_del_ifa(in_dev, ifap, 0); 896 ifa->ifa_mask = sin->sin_addr.s_addr; 897 ifa->ifa_prefixlen = inet_mask_len(ifa->ifa_mask); 898 899 /* See if current broadcast address matches 900 * with current netmask, then recalculate 901 * the broadcast address. Otherwise it's a 902 * funny address, so don't touch it since 903 * the user seems to know what (s)he's doing... 904 */ 905 if ((dev->flags & IFF_BROADCAST) && 906 (ifa->ifa_prefixlen < 31) && 907 (ifa->ifa_broadcast == 908 (ifa->ifa_local|~old_mask))) { 909 ifa->ifa_broadcast = (ifa->ifa_local | 910 ~sin->sin_addr.s_addr); 911 } 912 inet_insert_ifa(ifa); 913 } 914 break; 915 } 916done: 917 rtnl_unlock(); 918out: 919 return ret; 920rarok: 921 rtnl_unlock(); 922 ret = copy_to_user(arg, &ifr, sizeof(struct ifreq)) ? -EFAULT : 0; 923 goto out; 924} 925 926static int inet_gifconf(struct net_device *dev, char __user *buf, int len) 927{ 928 struct in_device *in_dev = __in_dev_get_rtnl(dev); 929 struct in_ifaddr *ifa; 930 struct ifreq ifr; 931 int done = 0; 932 933 if (!in_dev) 934 goto out; 935 936 for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) { 937 if (!buf) { 938 done += sizeof(ifr); 939 continue; 940 } 941 if (len < (int) sizeof(ifr)) 942 break; 943 memset(&ifr, 0, sizeof(struct ifreq)); 944 if (ifa->ifa_label) 945 strcpy(ifr.ifr_name, ifa->ifa_label); 946 else 947 strcpy(ifr.ifr_name, dev->name); 948 949 (*(struct sockaddr_in *)&ifr.ifr_addr).sin_family = AF_INET; 950 (*(struct sockaddr_in *)&ifr.ifr_addr).sin_addr.s_addr = 951 ifa->ifa_local; 952 953 if (copy_to_user(buf, &ifr, sizeof(struct ifreq))) { 954 done = -EFAULT; 955 break; 956 } 957 buf += sizeof(struct ifreq); 958 len -= sizeof(struct ifreq); 959 done += sizeof(struct ifreq); 960 } 961out: 962 return done; 963} 964 965__be32 inet_select_addr(const struct net_device *dev, __be32 dst, int scope) 966{ 967 __be32 addr = 0; 968 struct in_device *in_dev; 969 struct net *net = dev_net(dev); 970 971 rcu_read_lock(); 972 in_dev = __in_dev_get_rcu(dev); 973 if (!in_dev) 974 goto no_in_dev; 975 976 for_primary_ifa(in_dev) { 977 if (ifa->ifa_scope > scope) 978 continue; 979 if (!dst || inet_ifa_match(dst, ifa)) { 980 addr = ifa->ifa_local; 981 break; 982 } 983 if (!addr) 984 addr = ifa->ifa_local; 985 } endfor_ifa(in_dev); 986 987 if (addr) 988 goto out_unlock; 989no_in_dev: 990 991 /* Not loopback addresses on loopback should be preferred 992 in this case. It is importnat that lo is the first interface 993 in dev_base list. 994 */ 995 for_each_netdev_rcu(net, dev) { 996 in_dev = __in_dev_get_rcu(dev); 997 if (!in_dev) 998 continue; 999 1000 for_primary_ifa(in_dev) { 1001 if (ifa->ifa_scope != RT_SCOPE_LINK && 1002 ifa->ifa_scope <= scope) { 1003 addr = ifa->ifa_local; 1004 goto out_unlock; 1005 } 1006 } endfor_ifa(in_dev); 1007 } 1008out_unlock: 1009 rcu_read_unlock(); 1010 return addr; 1011} 1012EXPORT_SYMBOL(inet_select_addr); 1013 1014static __be32 confirm_addr_indev(struct in_device *in_dev, __be32 dst, 1015 __be32 local, int scope) 1016{ 1017 int same = 0; 1018 __be32 addr = 0; 1019 1020 for_ifa(in_dev) { 1021 if (!addr && 1022 (local == ifa->ifa_local || !local) && 1023 ifa->ifa_scope <= scope) { 1024 addr = ifa->ifa_local; 1025 if (same) 1026 break; 1027 } 1028 if (!same) { 1029 same = (!local || inet_ifa_match(local, ifa)) && 1030 (!dst || inet_ifa_match(dst, ifa)); 1031 if (same && addr) { 1032 if (local || !dst) 1033 break; 1034 /* Is the selected addr into dst subnet? */ 1035 if (inet_ifa_match(addr, ifa)) 1036 break; 1037 /* No, then can we use new local src? */ 1038 if (ifa->ifa_scope <= scope) { 1039 addr = ifa->ifa_local; 1040 break; 1041 } 1042 /* search for large dst subnet for addr */ 1043 same = 0; 1044 } 1045 } 1046 } endfor_ifa(in_dev); 1047 1048 return same ? addr : 0; 1049} 1050 1051/* 1052 * Confirm that local IP address exists using wildcards: 1053 * - in_dev: only on this interface, 0=any interface 1054 * - dst: only in the same subnet as dst, 0=any dst 1055 * - local: address, 0=autoselect the local address 1056 * - scope: maximum allowed scope value for the local address 1057 */ 1058__be32 inet_confirm_addr(struct in_device *in_dev, 1059 __be32 dst, __be32 local, int scope) 1060{ 1061 __be32 addr = 0; 1062 struct net_device *dev; 1063 struct net *net; 1064 1065 if (scope != RT_SCOPE_LINK) 1066 return confirm_addr_indev(in_dev, dst, local, scope); 1067 1068 net = dev_net(in_dev->dev); 1069 rcu_read_lock(); 1070 for_each_netdev_rcu(net, dev) { 1071 in_dev = __in_dev_get_rcu(dev); 1072 if (in_dev) { 1073 addr = confirm_addr_indev(in_dev, dst, local, scope); 1074 if (addr) 1075 break; 1076 } 1077 } 1078 rcu_read_unlock(); 1079 1080 return addr; 1081} 1082 1083/* 1084 * Device notifier 1085 */ 1086 1087int register_inetaddr_notifier(struct notifier_block *nb) 1088{ 1089 return blocking_notifier_chain_register(&inetaddr_chain, nb); 1090} 1091EXPORT_SYMBOL(register_inetaddr_notifier); 1092 1093int unregister_inetaddr_notifier(struct notifier_block *nb) 1094{ 1095 return blocking_notifier_chain_unregister(&inetaddr_chain, nb); 1096} 1097EXPORT_SYMBOL(unregister_inetaddr_notifier); 1098 1099/* Rename ifa_labels for a device name change. Make some effort to preserve 1100 * existing alias numbering and to create unique labels if possible. 1101*/ 1102static void inetdev_changename(struct net_device *dev, struct in_device *in_dev) 1103{ 1104 struct in_ifaddr *ifa; 1105 int named = 0; 1106 1107 for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) { 1108 char old[IFNAMSIZ], *dot; 1109 1110 memcpy(old, ifa->ifa_label, IFNAMSIZ); 1111 memcpy(ifa->ifa_label, dev->name, IFNAMSIZ); 1112 if (named++ == 0) 1113 goto skip; 1114 dot = strchr(old, ':'); 1115 if (dot == NULL) { 1116 sprintf(old, ":%d", named); 1117 dot = old; 1118 } 1119 if (strlen(dot) + strlen(dev->name) < IFNAMSIZ) 1120 strcat(ifa->ifa_label, dot); 1121 else 1122 strcpy(ifa->ifa_label + (IFNAMSIZ - strlen(dot) - 1), dot); 1123skip: 1124 rtmsg_ifa(RTM_NEWADDR, ifa, NULL, 0); 1125 } 1126} 1127 1128static inline bool inetdev_valid_mtu(unsigned mtu) 1129{ 1130 return mtu >= 68; 1131} 1132 1133static void inetdev_send_gratuitous_arp(struct net_device *dev, 1134 struct in_device *in_dev) 1135 1136{ 1137 struct in_ifaddr *ifa = in_dev->ifa_list; 1138 1139 if (!ifa) 1140 return; 1141 1142 arp_send(ARPOP_REQUEST, ETH_P_ARP, 1143 ifa->ifa_local, dev, 1144 ifa->ifa_local, NULL, 1145 dev->dev_addr, NULL); 1146} 1147 1148/* Called only under RTNL semaphore */ 1149 1150static int inetdev_event(struct notifier_block *this, unsigned long event, 1151 void *ptr) 1152{ 1153 struct net_device *dev = ptr; 1154 struct in_device *in_dev = __in_dev_get_rtnl(dev); 1155 1156 ASSERT_RTNL(); 1157 1158 if (!in_dev) { 1159 if (event == NETDEV_REGISTER) { 1160 in_dev = inetdev_init(dev); 1161 if (!in_dev) 1162 return notifier_from_errno(-ENOMEM); 1163 if (dev->flags & IFF_LOOPBACK) { 1164 IN_DEV_CONF_SET(in_dev, NOXFRM, 1); 1165 IN_DEV_CONF_SET(in_dev, NOPOLICY, 1); 1166 } 1167 } else if (event == NETDEV_CHANGEMTU) { 1168 /* Re-enabling IP */ 1169 if (inetdev_valid_mtu(dev->mtu)) 1170 in_dev = inetdev_init(dev); 1171 } 1172 goto out; 1173 } 1174 1175 switch (event) { 1176 case NETDEV_REGISTER: 1177 printk(KERN_DEBUG "inetdev_event: bug\n"); 1178 rcu_assign_pointer(dev->ip_ptr, NULL); 1179 break; 1180 case NETDEV_UP: 1181 if (!inetdev_valid_mtu(dev->mtu)) 1182 break; 1183 if (dev->flags & IFF_LOOPBACK) { 1184 struct in_ifaddr *ifa = inet_alloc_ifa(); 1185 1186 if (ifa) { 1187 INIT_HLIST_NODE(&ifa->hash); 1188 ifa->ifa_local = 1189 ifa->ifa_address = htonl(INADDR_LOOPBACK); 1190 ifa->ifa_prefixlen = 8; 1191 ifa->ifa_mask = inet_make_mask(8); 1192 in_dev_hold(in_dev); 1193 ifa->ifa_dev = in_dev; 1194 ifa->ifa_scope = RT_SCOPE_HOST; 1195 memcpy(ifa->ifa_label, dev->name, IFNAMSIZ); 1196 inet_insert_ifa(ifa); 1197 } 1198 } 1199 ip_mc_up(in_dev); 1200 /* fall through */ 1201 case NETDEV_CHANGEADDR: 1202 if (!IN_DEV_ARP_NOTIFY(in_dev)) 1203 break; 1204 /* fall through */ 1205 case NETDEV_NOTIFY_PEERS: 1206 case NETDEV_BONDING_FAILOVER: 1207 /* Send gratuitous ARP to notify of link change */ 1208 inetdev_send_gratuitous_arp(dev, in_dev); 1209 break; 1210 case NETDEV_DOWN: 1211 ip_mc_down(in_dev); 1212 break; 1213 case NETDEV_PRE_TYPE_CHANGE: 1214 ip_mc_unmap(in_dev); 1215 break; 1216 case NETDEV_POST_TYPE_CHANGE: 1217 ip_mc_remap(in_dev); 1218 break; 1219 case NETDEV_CHANGEMTU: 1220 if (inetdev_valid_mtu(dev->mtu)) 1221 break; 1222 /* disable IP when MTU is not enough */ 1223 case NETDEV_UNREGISTER: 1224 inetdev_destroy(in_dev); 1225 break; 1226 case NETDEV_CHANGENAME: 1227 /* Do not notify about label change, this event is 1228 * not interesting to applications using netlink. 1229 */ 1230 inetdev_changename(dev, in_dev); 1231 1232 devinet_sysctl_unregister(in_dev); 1233 devinet_sysctl_register(in_dev); 1234 break; 1235 } 1236out: 1237 return NOTIFY_DONE; 1238} 1239 1240static struct notifier_block ip_netdev_notifier = { 1241 .notifier_call = inetdev_event, 1242}; 1243 1244static inline size_t inet_nlmsg_size(void) 1245{ 1246 return NLMSG_ALIGN(sizeof(struct ifaddrmsg)) 1247 + nla_total_size(4) /* IFA_ADDRESS */ 1248 + nla_total_size(4) /* IFA_LOCAL */ 1249 + nla_total_size(4) /* IFA_BROADCAST */ 1250 + nla_total_size(IFNAMSIZ); /* IFA_LABEL */ 1251} 1252 1253static int inet_fill_ifaddr(struct sk_buff *skb, struct in_ifaddr *ifa, 1254 u32 pid, u32 seq, int event, unsigned int flags) 1255{ 1256 struct ifaddrmsg *ifm; 1257 struct nlmsghdr *nlh; 1258 1259 nlh = nlmsg_put(skb, pid, seq, event, sizeof(*ifm), flags); 1260 if (nlh == NULL) 1261 return -EMSGSIZE; 1262 1263 ifm = nlmsg_data(nlh); 1264 ifm->ifa_family = AF_INET; 1265 ifm->ifa_prefixlen = ifa->ifa_prefixlen; 1266 ifm->ifa_flags = ifa->ifa_flags|IFA_F_PERMANENT; 1267 ifm->ifa_scope = ifa->ifa_scope; 1268 ifm->ifa_index = ifa->ifa_dev->dev->ifindex; 1269 1270 if (ifa->ifa_address) 1271 NLA_PUT_BE32(skb, IFA_ADDRESS, ifa->ifa_address); 1272 1273 if (ifa->ifa_local) 1274 NLA_PUT_BE32(skb, IFA_LOCAL, ifa->ifa_local); 1275 1276 if (ifa->ifa_broadcast) 1277 NLA_PUT_BE32(skb, IFA_BROADCAST, ifa->ifa_broadcast); 1278 1279 if (ifa->ifa_label[0]) 1280 NLA_PUT_STRING(skb, IFA_LABEL, ifa->ifa_label); 1281 1282 return nlmsg_end(skb, nlh); 1283 1284nla_put_failure: 1285 nlmsg_cancel(skb, nlh); 1286 return -EMSGSIZE; 1287} 1288 1289static int inet_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb) 1290{ 1291 struct net *net = sock_net(skb->sk); 1292 int h, s_h; 1293 int idx, s_idx; 1294 int ip_idx, s_ip_idx; 1295 struct net_device *dev; 1296 struct in_device *in_dev; 1297 struct in_ifaddr *ifa; 1298 struct hlist_head *head; 1299 struct hlist_node *node; 1300 1301 s_h = cb->args[0]; 1302 s_idx = idx = cb->args[1]; 1303 s_ip_idx = ip_idx = cb->args[2]; 1304 1305 for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) { 1306 idx = 0; 1307 head = &net->dev_index_head[h]; 1308 rcu_read_lock(); 1309 hlist_for_each_entry_rcu(dev, node, head, index_hlist) { 1310 if (idx < s_idx) 1311 goto cont; 1312 if (h > s_h || idx > s_idx) 1313 s_ip_idx = 0; 1314 in_dev = __in_dev_get_rcu(dev); 1315 if (!in_dev) 1316 goto cont; 1317 1318 for (ifa = in_dev->ifa_list, ip_idx = 0; ifa; 1319 ifa = ifa->ifa_next, ip_idx++) { 1320 if (ip_idx < s_ip_idx) 1321 continue; 1322 if (inet_fill_ifaddr(skb, ifa, 1323 NETLINK_CB(cb->skb).pid, 1324 cb->nlh->nlmsg_seq, 1325 RTM_NEWADDR, NLM_F_MULTI) <= 0) { 1326 rcu_read_unlock(); 1327 goto done; 1328 } 1329 } 1330cont: 1331 idx++; 1332 } 1333 rcu_read_unlock(); 1334 } 1335 1336done: 1337 cb->args[0] = h; 1338 cb->args[1] = idx; 1339 cb->args[2] = ip_idx; 1340 1341 return skb->len; 1342} 1343 1344static void rtmsg_ifa(int event, struct in_ifaddr *ifa, struct nlmsghdr *nlh, 1345 u32 pid) 1346{ 1347 struct sk_buff *skb; 1348 u32 seq = nlh ? nlh->nlmsg_seq : 0; 1349 int err = -ENOBUFS; 1350 struct net *net; 1351 1352 net = dev_net(ifa->ifa_dev->dev); 1353 skb = nlmsg_new(inet_nlmsg_size(), GFP_KERNEL); 1354 if (skb == NULL) 1355 goto errout; 1356 1357 err = inet_fill_ifaddr(skb, ifa, pid, seq, event, 0); 1358 if (err < 0) { 1359 /* -EMSGSIZE implies BUG in inet_nlmsg_size() */ 1360 WARN_ON(err == -EMSGSIZE); 1361 kfree_skb(skb); 1362 goto errout; 1363 } 1364 rtnl_notify(skb, net, pid, RTNLGRP_IPV4_IFADDR, nlh, GFP_KERNEL); 1365 return; 1366errout: 1367 if (err < 0) 1368 rtnl_set_sk_err(net, RTNLGRP_IPV4_IFADDR, err); 1369} 1370 1371static size_t inet_get_link_af_size(const struct net_device *dev) 1372{ 1373 struct in_device *in_dev = __in_dev_get_rtnl(dev); 1374 1375 if (!in_dev) 1376 return 0; 1377 1378 return nla_total_size(IPV4_DEVCONF_MAX * 4); /* IFLA_INET_CONF */ 1379} 1380 1381static int inet_fill_link_af(struct sk_buff *skb, const struct net_device *dev) 1382{ 1383 struct in_device *in_dev = __in_dev_get_rtnl(dev); 1384 struct nlattr *nla; 1385 int i; 1386 1387 if (!in_dev) 1388 return -ENODATA; 1389 1390 nla = nla_reserve(skb, IFLA_INET_CONF, IPV4_DEVCONF_MAX * 4); 1391 if (nla == NULL) 1392 return -EMSGSIZE; 1393 1394 for (i = 0; i < IPV4_DEVCONF_MAX; i++) 1395 ((u32 *) nla_data(nla))[i] = in_dev->cnf.data[i]; 1396 1397 return 0; 1398} 1399 1400static const struct nla_policy inet_af_policy[IFLA_INET_MAX+1] = { 1401 [IFLA_INET_CONF] = { .type = NLA_NESTED }, 1402}; 1403 1404static int inet_validate_link_af(const struct net_device *dev, 1405 const struct nlattr *nla) 1406{ 1407 struct nlattr *a, *tb[IFLA_INET_MAX+1]; 1408 int err, rem; 1409 1410 if (dev && !__in_dev_get_rtnl(dev)) 1411 return -EAFNOSUPPORT; 1412 1413 err = nla_parse_nested(tb, IFLA_INET_MAX, nla, inet_af_policy); 1414 if (err < 0) 1415 return err; 1416 1417 if (tb[IFLA_INET_CONF]) { 1418 nla_for_each_nested(a, tb[IFLA_INET_CONF], rem) { 1419 int cfgid = nla_type(a); 1420 1421 if (nla_len(a) < 4) 1422 return -EINVAL; 1423 1424 if (cfgid <= 0 || cfgid > IPV4_DEVCONF_MAX) 1425 return -EINVAL; 1426 } 1427 } 1428 1429 return 0; 1430} 1431 1432static int inet_set_link_af(struct net_device *dev, const struct nlattr *nla) 1433{ 1434 struct in_device *in_dev = __in_dev_get_rtnl(dev); 1435 struct nlattr *a, *tb[IFLA_INET_MAX+1]; 1436 int rem; 1437 1438 if (!in_dev) 1439 return -EAFNOSUPPORT; 1440 1441 if (nla_parse_nested(tb, IFLA_INET_MAX, nla, NULL) < 0) 1442 BUG(); 1443 1444 if (tb[IFLA_INET_CONF]) { 1445 nla_for_each_nested(a, tb[IFLA_INET_CONF], rem) 1446 ipv4_devconf_set(in_dev, nla_type(a), nla_get_u32(a)); 1447 } 1448 1449 return 0; 1450} 1451 1452#ifdef CONFIG_SYSCTL 1453 1454static void devinet_copy_dflt_conf(struct net *net, int i) 1455{ 1456 struct net_device *dev; 1457 1458 rcu_read_lock(); 1459 for_each_netdev_rcu(net, dev) { 1460 struct in_device *in_dev; 1461 1462 in_dev = __in_dev_get_rcu(dev); 1463 if (in_dev && !test_bit(i, in_dev->cnf.state)) 1464 in_dev->cnf.data[i] = net->ipv4.devconf_dflt->data[i]; 1465 } 1466 rcu_read_unlock(); 1467} 1468 1469/* called with RTNL locked */ 1470static void inet_forward_change(struct net *net) 1471{ 1472 struct net_device *dev; 1473 int on = IPV4_DEVCONF_ALL(net, FORWARDING); 1474 1475 IPV4_DEVCONF_ALL(net, ACCEPT_REDIRECTS) = !on; 1476 IPV4_DEVCONF_DFLT(net, FORWARDING) = on; 1477 1478 for_each_netdev(net, dev) { 1479 struct in_device *in_dev; 1480 if (on) 1481 dev_disable_lro(dev); 1482 rcu_read_lock(); 1483 in_dev = __in_dev_get_rcu(dev); 1484 if (in_dev) 1485 IN_DEV_CONF_SET(in_dev, FORWARDING, on); 1486 rcu_read_unlock(); 1487 } 1488} 1489 1490static int devinet_conf_proc(ctl_table *ctl, int write, 1491 void __user *buffer, 1492 size_t *lenp, loff_t *ppos) 1493{ 1494 int ret = proc_dointvec(ctl, write, buffer, lenp, ppos); 1495 1496 if (write) { 1497 struct ipv4_devconf *cnf = ctl->extra1; 1498 struct net *net = ctl->extra2; 1499 int i = (int *)ctl->data - cnf->data; 1500 1501 set_bit(i, cnf->state); 1502 1503 if (cnf == net->ipv4.devconf_dflt) 1504 devinet_copy_dflt_conf(net, i); 1505 } 1506 1507 return ret; 1508} 1509 1510static int devinet_sysctl_forward(ctl_table *ctl, int write, 1511 void __user *buffer, 1512 size_t *lenp, loff_t *ppos) 1513{ 1514 int *valp = ctl->data; 1515 int val = *valp; 1516 loff_t pos = *ppos; 1517 int ret = proc_dointvec(ctl, write, buffer, lenp, ppos); 1518 1519 if (write && *valp != val) { 1520 struct net *net = ctl->extra2; 1521 1522 if (valp != &IPV4_DEVCONF_DFLT(net, FORWARDING)) { 1523 if (!rtnl_trylock()) { 1524 /* Restore the original values before restarting */ 1525 *valp = val; 1526 *ppos = pos; 1527 return restart_syscall(); 1528 } 1529 if (valp == &IPV4_DEVCONF_ALL(net, FORWARDING)) { 1530 inet_forward_change(net); 1531 } else if (*valp) { 1532 struct ipv4_devconf *cnf = ctl->extra1; 1533 struct in_device *idev = 1534 container_of(cnf, struct in_device, cnf); 1535 dev_disable_lro(idev->dev); 1536 } 1537 rtnl_unlock(); 1538 rt_cache_flush(net, 0); 1539 } 1540 } 1541 1542 return ret; 1543} 1544 1545static int ipv4_doint_and_flush(ctl_table *ctl, int write, 1546 void __user *buffer, 1547 size_t *lenp, loff_t *ppos) 1548{ 1549 int *valp = ctl->data; 1550 int val = *valp; 1551 int ret = proc_dointvec(ctl, write, buffer, lenp, ppos); 1552 struct net *net = ctl->extra2; 1553 1554 if (write && *valp != val) 1555 rt_cache_flush(net, 0); 1556 1557 return ret; 1558} 1559 1560#define DEVINET_SYSCTL_ENTRY(attr, name, mval, proc) \ 1561 { \ 1562 .procname = name, \ 1563 .data = ipv4_devconf.data + \ 1564 IPV4_DEVCONF_ ## attr - 1, \ 1565 .maxlen = sizeof(int), \ 1566 .mode = mval, \ 1567 .proc_handler = proc, \ 1568 .extra1 = &ipv4_devconf, \ 1569 } 1570 1571#define DEVINET_SYSCTL_RW_ENTRY(attr, name) \ 1572 DEVINET_SYSCTL_ENTRY(attr, name, 0644, devinet_conf_proc) 1573 1574#define DEVINET_SYSCTL_RO_ENTRY(attr, name) \ 1575 DEVINET_SYSCTL_ENTRY(attr, name, 0444, devinet_conf_proc) 1576 1577#define DEVINET_SYSCTL_COMPLEX_ENTRY(attr, name, proc) \ 1578 DEVINET_SYSCTL_ENTRY(attr, name, 0644, proc) 1579 1580#define DEVINET_SYSCTL_FLUSHING_ENTRY(attr, name) \ 1581 DEVINET_SYSCTL_COMPLEX_ENTRY(attr, name, ipv4_doint_and_flush) 1582 1583static struct devinet_sysctl_table { 1584 struct ctl_table_header *sysctl_header; 1585 struct ctl_table devinet_vars[__IPV4_DEVCONF_MAX]; 1586 char *dev_name; 1587} devinet_sysctl = { 1588 .devinet_vars = { 1589 DEVINET_SYSCTL_COMPLEX_ENTRY(FORWARDING, "forwarding", 1590 devinet_sysctl_forward), 1591 DEVINET_SYSCTL_RO_ENTRY(MC_FORWARDING, "mc_forwarding"), 1592 1593 DEVINET_SYSCTL_RW_ENTRY(ACCEPT_REDIRECTS, "accept_redirects"), 1594 DEVINET_SYSCTL_RW_ENTRY(SECURE_REDIRECTS, "secure_redirects"), 1595 DEVINET_SYSCTL_RW_ENTRY(SHARED_MEDIA, "shared_media"), 1596 DEVINET_SYSCTL_RW_ENTRY(RP_FILTER, "rp_filter"), 1597 DEVINET_SYSCTL_RW_ENTRY(SEND_REDIRECTS, "send_redirects"), 1598 DEVINET_SYSCTL_RW_ENTRY(ACCEPT_SOURCE_ROUTE, 1599 "accept_source_route"), 1600 DEVINET_SYSCTL_RW_ENTRY(ACCEPT_LOCAL, "accept_local"), 1601 DEVINET_SYSCTL_RW_ENTRY(SRC_VMARK, "src_valid_mark"), 1602 DEVINET_SYSCTL_RW_ENTRY(PROXY_ARP, "proxy_arp"), 1603 DEVINET_SYSCTL_RW_ENTRY(MEDIUM_ID, "medium_id"), 1604 DEVINET_SYSCTL_RW_ENTRY(BOOTP_RELAY, "bootp_relay"), 1605 DEVINET_SYSCTL_RW_ENTRY(LOG_MARTIANS, "log_martians"), 1606 DEVINET_SYSCTL_RW_ENTRY(TAG, "tag"), 1607 DEVINET_SYSCTL_RW_ENTRY(ARPFILTER, "arp_filter"), 1608 DEVINET_SYSCTL_RW_ENTRY(ARP_ANNOUNCE, "arp_announce"), 1609 DEVINET_SYSCTL_RW_ENTRY(ARP_IGNORE, "arp_ignore"), 1610 DEVINET_SYSCTL_RW_ENTRY(ARP_ACCEPT, "arp_accept"), 1611 DEVINET_SYSCTL_RW_ENTRY(ARP_NOTIFY, "arp_notify"), 1612 DEVINET_SYSCTL_RW_ENTRY(PROXY_ARP_PVLAN, "proxy_arp_pvlan"), 1613 1614 DEVINET_SYSCTL_FLUSHING_ENTRY(NOXFRM, "disable_xfrm"), 1615 DEVINET_SYSCTL_FLUSHING_ENTRY(NOPOLICY, "disable_policy"), 1616 DEVINET_SYSCTL_FLUSHING_ENTRY(FORCE_IGMP_VERSION, 1617 "force_igmp_version"), 1618 DEVINET_SYSCTL_FLUSHING_ENTRY(PROMOTE_SECONDARIES, 1619 "promote_secondaries"), 1620 }, 1621}; 1622 1623static int __devinet_sysctl_register(struct net *net, char *dev_name, 1624 struct ipv4_devconf *p) 1625{ 1626 int i; 1627 struct devinet_sysctl_table *t; 1628 1629#define DEVINET_CTL_PATH_DEV 3 1630 1631 struct ctl_path devinet_ctl_path[] = { 1632 { .procname = "net", }, 1633 { .procname = "ipv4", }, 1634 { .procname = "conf", }, 1635 { /* to be set */ }, 1636 { }, 1637 }; 1638 1639 t = kmemdup(&devinet_sysctl, sizeof(*t), GFP_KERNEL); 1640 if (!t) 1641 goto out; 1642 1643 for (i = 0; i < ARRAY_SIZE(t->devinet_vars) - 1; i++) { 1644 t->devinet_vars[i].data += (char *)p - (char *)&ipv4_devconf; 1645 t->devinet_vars[i].extra1 = p; 1646 t->devinet_vars[i].extra2 = net; 1647 } 1648 1649 /* 1650 * Make a copy of dev_name, because '.procname' is regarded as const 1651 * by sysctl and we wouldn't want anyone to change it under our feet 1652 * (see SIOCSIFNAME). 1653 */ 1654 t->dev_name = kstrdup(dev_name, GFP_KERNEL); 1655 if (!t->dev_name) 1656 goto free; 1657 1658 devinet_ctl_path[DEVINET_CTL_PATH_DEV].procname = t->dev_name; 1659 1660 t->sysctl_header = register_net_sysctl_table(net, devinet_ctl_path, 1661 t->devinet_vars); 1662 if (!t->sysctl_header) 1663 goto free_procname; 1664 1665 p->sysctl = t; 1666 return 0; 1667 1668free_procname: 1669 kfree(t->dev_name); 1670free: 1671 kfree(t); 1672out: 1673 return -ENOBUFS; 1674} 1675 1676static void __devinet_sysctl_unregister(struct ipv4_devconf *cnf) 1677{ 1678 struct devinet_sysctl_table *t = cnf->sysctl; 1679 1680 if (t == NULL) 1681 return; 1682 1683 cnf->sysctl = NULL; 1684 unregister_sysctl_table(t->sysctl_header); 1685 kfree(t->dev_name); 1686 kfree(t); 1687} 1688 1689static void devinet_sysctl_register(struct in_device *idev) 1690{ 1691 neigh_sysctl_register(idev->dev, idev->arp_parms, "ipv4", NULL); 1692 __devinet_sysctl_register(dev_net(idev->dev), idev->dev->name, 1693 &idev->cnf); 1694} 1695 1696static void devinet_sysctl_unregister(struct in_device *idev) 1697{ 1698 __devinet_sysctl_unregister(&idev->cnf); 1699 neigh_sysctl_unregister(idev->arp_parms); 1700} 1701 1702static struct ctl_table ctl_forward_entry[] = { 1703 { 1704 .procname = "ip_forward", 1705 .data = &ipv4_devconf.data[ 1706 IPV4_DEVCONF_FORWARDING - 1], 1707 .maxlen = sizeof(int), 1708 .mode = 0644, 1709 .proc_handler = devinet_sysctl_forward, 1710 .extra1 = &ipv4_devconf, 1711 .extra2 = &init_net, 1712 }, 1713 { }, 1714}; 1715 1716static __net_initdata struct ctl_path net_ipv4_path[] = { 1717 { .procname = "net", }, 1718 { .procname = "ipv4", }, 1719 { }, 1720}; 1721#endif 1722 1723static __net_init int devinet_init_net(struct net *net) 1724{ 1725 int err; 1726 struct ipv4_devconf *all, *dflt; 1727#ifdef CONFIG_SYSCTL 1728 struct ctl_table *tbl = ctl_forward_entry; 1729 struct ctl_table_header *forw_hdr; 1730#endif 1731 1732 err = -ENOMEM; 1733 all = &ipv4_devconf; 1734 dflt = &ipv4_devconf_dflt; 1735 1736 if (!net_eq(net, &init_net)) { 1737 all = kmemdup(all, sizeof(ipv4_devconf), GFP_KERNEL); 1738 if (all == NULL) 1739 goto err_alloc_all; 1740 1741 dflt = kmemdup(dflt, sizeof(ipv4_devconf_dflt), GFP_KERNEL); 1742 if (dflt == NULL) 1743 goto err_alloc_dflt; 1744 1745#ifdef CONFIG_SYSCTL 1746 tbl = kmemdup(tbl, sizeof(ctl_forward_entry), GFP_KERNEL); 1747 if (tbl == NULL) 1748 goto err_alloc_ctl; 1749 1750 tbl[0].data = &all->data[IPV4_DEVCONF_FORWARDING - 1]; 1751 tbl[0].extra1 = all; 1752 tbl[0].extra2 = net; 1753#endif 1754 } 1755 1756#ifdef CONFIG_SYSCTL 1757 err = __devinet_sysctl_register(net, "all", all); 1758 if (err < 0) 1759 goto err_reg_all; 1760 1761 err = __devinet_sysctl_register(net, "default", dflt); 1762 if (err < 0) 1763 goto err_reg_dflt; 1764 1765 err = -ENOMEM; 1766 forw_hdr = register_net_sysctl_table(net, net_ipv4_path, tbl); 1767 if (forw_hdr == NULL) 1768 goto err_reg_ctl; 1769 net->ipv4.forw_hdr = forw_hdr; 1770#endif 1771 1772 net->ipv4.devconf_all = all; 1773 net->ipv4.devconf_dflt = dflt; 1774 return 0; 1775 1776#ifdef CONFIG_SYSCTL 1777err_reg_ctl: 1778 __devinet_sysctl_unregister(dflt); 1779err_reg_dflt: 1780 __devinet_sysctl_unregister(all); 1781err_reg_all: 1782 if (tbl != ctl_forward_entry) 1783 kfree(tbl); 1784err_alloc_ctl: 1785#endif 1786 if (dflt != &ipv4_devconf_dflt) 1787 kfree(dflt); 1788err_alloc_dflt: 1789 if (all != &ipv4_devconf) 1790 kfree(all); 1791err_alloc_all: 1792 return err; 1793} 1794 1795static __net_exit void devinet_exit_net(struct net *net) 1796{ 1797#ifdef CONFIG_SYSCTL 1798 struct ctl_table *tbl; 1799 1800 tbl = net->ipv4.forw_hdr->ctl_table_arg; 1801 unregister_net_sysctl_table(net->ipv4.forw_hdr); 1802 __devinet_sysctl_unregister(net->ipv4.devconf_dflt); 1803 __devinet_sysctl_unregister(net->ipv4.devconf_all); 1804 kfree(tbl); 1805#endif 1806 kfree(net->ipv4.devconf_dflt); 1807 kfree(net->ipv4.devconf_all); 1808} 1809 1810static __net_initdata struct pernet_operations devinet_ops = { 1811 .init = devinet_init_net, 1812 .exit = devinet_exit_net, 1813}; 1814 1815static struct rtnl_af_ops inet_af_ops = { 1816 .family = AF_INET, 1817 .fill_link_af = inet_fill_link_af, 1818 .get_link_af_size = inet_get_link_af_size, 1819 .validate_link_af = inet_validate_link_af, 1820 .set_link_af = inet_set_link_af, 1821}; 1822 1823void __init devinet_init(void) 1824{ 1825 int i; 1826 1827 for (i = 0; i < IN4_ADDR_HSIZE; i++) 1828 INIT_HLIST_HEAD(&inet_addr_lst[i]); 1829 1830 register_pernet_subsys(&devinet_ops); 1831 1832 register_gifconf(PF_INET, inet_gifconf); 1833 register_netdevice_notifier(&ip_netdev_notifier); 1834 1835 rtnl_af_register(&inet_af_ops); 1836 1837 rtnl_register(PF_INET, RTM_NEWADDR, inet_rtm_newaddr, NULL); 1838 rtnl_register(PF_INET, RTM_DELADDR, inet_rtm_deladdr, NULL); 1839 rtnl_register(PF_INET, RTM_GETADDR, NULL, inet_dump_ifaddr); 1840} 1841 1842