devinet.c revision 91df42bedccb919902c7cf7eb876c982ae7f1b1d
1/* 2 * NET3 IP device support routines. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public License 6 * as published by the Free Software Foundation; either version 7 * 2 of the License, or (at your option) any later version. 8 * 9 * Derived from the IP parts of dev.c 1.0.19 10 * Authors: Ross Biro 11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> 12 * Mark Evans, <evansmp@uhura.aston.ac.uk> 13 * 14 * Additional Authors: 15 * Alan Cox, <gw4pts@gw4pts.ampr.org> 16 * Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> 17 * 18 * Changes: 19 * Alexey Kuznetsov: pa_* fields are replaced with ifaddr 20 * lists. 21 * Cyrus Durgin: updated for kmod 22 * Matthias Andree: in devinet_ioctl, compare label and 23 * address (4.4BSD alias style support), 24 * fall back to comparing just the label 25 * if no match found. 26 */ 27 28 29#include <asm/uaccess.h> 30#include <linux/bitops.h> 31#include <linux/capability.h> 32#include <linux/module.h> 33#include <linux/types.h> 34#include <linux/kernel.h> 35#include <linux/string.h> 36#include <linux/mm.h> 37#include <linux/socket.h> 38#include <linux/sockios.h> 39#include <linux/in.h> 40#include <linux/errno.h> 41#include <linux/interrupt.h> 42#include <linux/if_addr.h> 43#include <linux/if_ether.h> 44#include <linux/inet.h> 45#include <linux/netdevice.h> 46#include <linux/etherdevice.h> 47#include <linux/skbuff.h> 48#include <linux/init.h> 49#include <linux/notifier.h> 50#include <linux/inetdevice.h> 51#include <linux/igmp.h> 52#include <linux/slab.h> 53#include <linux/hash.h> 54#ifdef CONFIG_SYSCTL 55#include <linux/sysctl.h> 56#endif 57#include <linux/kmod.h> 58 59#include <net/arp.h> 60#include <net/ip.h> 61#include <net/route.h> 62#include <net/ip_fib.h> 63#include <net/rtnetlink.h> 64#include <net/net_namespace.h> 65 66#include "fib_lookup.h" 67 68static struct ipv4_devconf ipv4_devconf = { 69 .data = { 70 [IPV4_DEVCONF_ACCEPT_REDIRECTS - 1] = 1, 71 [IPV4_DEVCONF_SEND_REDIRECTS - 1] = 1, 72 [IPV4_DEVCONF_SECURE_REDIRECTS - 1] = 1, 73 [IPV4_DEVCONF_SHARED_MEDIA - 1] = 1, 74 }, 75}; 76 77static struct ipv4_devconf ipv4_devconf_dflt = { 78 .data = { 79 [IPV4_DEVCONF_ACCEPT_REDIRECTS - 1] = 1, 80 [IPV4_DEVCONF_SEND_REDIRECTS - 1] = 1, 81 [IPV4_DEVCONF_SECURE_REDIRECTS - 1] = 1, 82 [IPV4_DEVCONF_SHARED_MEDIA - 1] = 1, 83 [IPV4_DEVCONF_ACCEPT_SOURCE_ROUTE - 1] = 1, 84 }, 85}; 86 87#define IPV4_DEVCONF_DFLT(net, attr) \ 88 IPV4_DEVCONF((*net->ipv4.devconf_dflt), attr) 89 90static const struct nla_policy ifa_ipv4_policy[IFA_MAX+1] = { 91 [IFA_LOCAL] = { .type = NLA_U32 }, 92 [IFA_ADDRESS] = { .type = NLA_U32 }, 93 [IFA_BROADCAST] = { .type = NLA_U32 }, 94 [IFA_LABEL] = { .type = NLA_STRING, .len = IFNAMSIZ - 1 }, 95}; 96 97/* inet_addr_hash's shifting is dependent upon this IN4_ADDR_HSIZE 98 * value. So if you change this define, make appropriate changes to 99 * inet_addr_hash as well. 100 */ 101#define IN4_ADDR_HSIZE 256 102static struct hlist_head inet_addr_lst[IN4_ADDR_HSIZE]; 103static DEFINE_SPINLOCK(inet_addr_hash_lock); 104 105static inline unsigned int inet_addr_hash(struct net *net, __be32 addr) 106{ 107 u32 val = (__force u32) addr ^ hash_ptr(net, 8); 108 109 return ((val ^ (val >> 8) ^ (val >> 16) ^ (val >> 24)) & 110 (IN4_ADDR_HSIZE - 1)); 111} 112 113static void inet_hash_insert(struct net *net, struct in_ifaddr *ifa) 114{ 115 unsigned int hash = inet_addr_hash(net, ifa->ifa_local); 116 117 spin_lock(&inet_addr_hash_lock); 118 hlist_add_head_rcu(&ifa->hash, &inet_addr_lst[hash]); 119 spin_unlock(&inet_addr_hash_lock); 120} 121 122static void inet_hash_remove(struct in_ifaddr *ifa) 123{ 124 spin_lock(&inet_addr_hash_lock); 125 hlist_del_init_rcu(&ifa->hash); 126 spin_unlock(&inet_addr_hash_lock); 127} 128 129/** 130 * __ip_dev_find - find the first device with a given source address. 131 * @net: the net namespace 132 * @addr: the source address 133 * @devref: if true, take a reference on the found device 134 * 135 * If a caller uses devref=false, it should be protected by RCU, or RTNL 136 */ 137struct net_device *__ip_dev_find(struct net *net, __be32 addr, bool devref) 138{ 139 unsigned int hash = inet_addr_hash(net, addr); 140 struct net_device *result = NULL; 141 struct in_ifaddr *ifa; 142 struct hlist_node *node; 143 144 rcu_read_lock(); 145 hlist_for_each_entry_rcu(ifa, node, &inet_addr_lst[hash], hash) { 146 struct net_device *dev = ifa->ifa_dev->dev; 147 148 if (!net_eq(dev_net(dev), net)) 149 continue; 150 if (ifa->ifa_local == addr) { 151 result = dev; 152 break; 153 } 154 } 155 if (!result) { 156 struct flowi4 fl4 = { .daddr = addr }; 157 struct fib_result res = { 0 }; 158 struct fib_table *local; 159 160 /* Fallback to FIB local table so that communication 161 * over loopback subnets work. 162 */ 163 local = fib_get_table(net, RT_TABLE_LOCAL); 164 if (local && 165 !fib_table_lookup(local, &fl4, &res, FIB_LOOKUP_NOREF) && 166 res.type == RTN_LOCAL) 167 result = FIB_RES_DEV(res); 168 } 169 if (result && devref) 170 dev_hold(result); 171 rcu_read_unlock(); 172 return result; 173} 174EXPORT_SYMBOL(__ip_dev_find); 175 176static void rtmsg_ifa(int event, struct in_ifaddr *, struct nlmsghdr *, u32); 177 178static BLOCKING_NOTIFIER_HEAD(inetaddr_chain); 179static void inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap, 180 int destroy); 181#ifdef CONFIG_SYSCTL 182static void devinet_sysctl_register(struct in_device *idev); 183static void devinet_sysctl_unregister(struct in_device *idev); 184#else 185static inline void devinet_sysctl_register(struct in_device *idev) 186{ 187} 188static inline void devinet_sysctl_unregister(struct in_device *idev) 189{ 190} 191#endif 192 193/* Locks all the inet devices. */ 194 195static struct in_ifaddr *inet_alloc_ifa(void) 196{ 197 return kzalloc(sizeof(struct in_ifaddr), GFP_KERNEL); 198} 199 200static void inet_rcu_free_ifa(struct rcu_head *head) 201{ 202 struct in_ifaddr *ifa = container_of(head, struct in_ifaddr, rcu_head); 203 if (ifa->ifa_dev) 204 in_dev_put(ifa->ifa_dev); 205 kfree(ifa); 206} 207 208static inline void inet_free_ifa(struct in_ifaddr *ifa) 209{ 210 call_rcu(&ifa->rcu_head, inet_rcu_free_ifa); 211} 212 213void in_dev_finish_destroy(struct in_device *idev) 214{ 215 struct net_device *dev = idev->dev; 216 217 WARN_ON(idev->ifa_list); 218 WARN_ON(idev->mc_list); 219#ifdef NET_REFCNT_DEBUG 220 pr_debug("%s: %p=%s\n", __func__, idev, dev ? dev->name : "NIL"); 221#endif 222 dev_put(dev); 223 if (!idev->dead) 224 pr_err("Freeing alive in_device %p\n", idev); 225 else 226 kfree(idev); 227} 228EXPORT_SYMBOL(in_dev_finish_destroy); 229 230static struct in_device *inetdev_init(struct net_device *dev) 231{ 232 struct in_device *in_dev; 233 234 ASSERT_RTNL(); 235 236 in_dev = kzalloc(sizeof(*in_dev), GFP_KERNEL); 237 if (!in_dev) 238 goto out; 239 memcpy(&in_dev->cnf, dev_net(dev)->ipv4.devconf_dflt, 240 sizeof(in_dev->cnf)); 241 in_dev->cnf.sysctl = NULL; 242 in_dev->dev = dev; 243 in_dev->arp_parms = neigh_parms_alloc(dev, &arp_tbl); 244 if (!in_dev->arp_parms) 245 goto out_kfree; 246 if (IPV4_DEVCONF(in_dev->cnf, FORWARDING)) 247 dev_disable_lro(dev); 248 /* Reference in_dev->dev */ 249 dev_hold(dev); 250 /* Account for reference dev->ip_ptr (below) */ 251 in_dev_hold(in_dev); 252 253 devinet_sysctl_register(in_dev); 254 ip_mc_init_dev(in_dev); 255 if (dev->flags & IFF_UP) 256 ip_mc_up(in_dev); 257 258 /* we can receive as soon as ip_ptr is set -- do this last */ 259 rcu_assign_pointer(dev->ip_ptr, in_dev); 260out: 261 return in_dev; 262out_kfree: 263 kfree(in_dev); 264 in_dev = NULL; 265 goto out; 266} 267 268static void in_dev_rcu_put(struct rcu_head *head) 269{ 270 struct in_device *idev = container_of(head, struct in_device, rcu_head); 271 in_dev_put(idev); 272} 273 274static void inetdev_destroy(struct in_device *in_dev) 275{ 276 struct in_ifaddr *ifa; 277 struct net_device *dev; 278 279 ASSERT_RTNL(); 280 281 dev = in_dev->dev; 282 283 in_dev->dead = 1; 284 285 ip_mc_destroy_dev(in_dev); 286 287 while ((ifa = in_dev->ifa_list) != NULL) { 288 inet_del_ifa(in_dev, &in_dev->ifa_list, 0); 289 inet_free_ifa(ifa); 290 } 291 292 RCU_INIT_POINTER(dev->ip_ptr, NULL); 293 294 devinet_sysctl_unregister(in_dev); 295 neigh_parms_release(&arp_tbl, in_dev->arp_parms); 296 arp_ifdown(dev); 297 298 call_rcu(&in_dev->rcu_head, in_dev_rcu_put); 299} 300 301int inet_addr_onlink(struct in_device *in_dev, __be32 a, __be32 b) 302{ 303 rcu_read_lock(); 304 for_primary_ifa(in_dev) { 305 if (inet_ifa_match(a, ifa)) { 306 if (!b || inet_ifa_match(b, ifa)) { 307 rcu_read_unlock(); 308 return 1; 309 } 310 } 311 } endfor_ifa(in_dev); 312 rcu_read_unlock(); 313 return 0; 314} 315 316static void __inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap, 317 int destroy, struct nlmsghdr *nlh, u32 pid) 318{ 319 struct in_ifaddr *promote = NULL; 320 struct in_ifaddr *ifa, *ifa1 = *ifap; 321 struct in_ifaddr *last_prim = in_dev->ifa_list; 322 struct in_ifaddr *prev_prom = NULL; 323 int do_promote = IN_DEV_PROMOTE_SECONDARIES(in_dev); 324 325 ASSERT_RTNL(); 326 327 /* 1. Deleting primary ifaddr forces deletion all secondaries 328 * unless alias promotion is set 329 **/ 330 331 if (!(ifa1->ifa_flags & IFA_F_SECONDARY)) { 332 struct in_ifaddr **ifap1 = &ifa1->ifa_next; 333 334 while ((ifa = *ifap1) != NULL) { 335 if (!(ifa->ifa_flags & IFA_F_SECONDARY) && 336 ifa1->ifa_scope <= ifa->ifa_scope) 337 last_prim = ifa; 338 339 if (!(ifa->ifa_flags & IFA_F_SECONDARY) || 340 ifa1->ifa_mask != ifa->ifa_mask || 341 !inet_ifa_match(ifa1->ifa_address, ifa)) { 342 ifap1 = &ifa->ifa_next; 343 prev_prom = ifa; 344 continue; 345 } 346 347 if (!do_promote) { 348 inet_hash_remove(ifa); 349 *ifap1 = ifa->ifa_next; 350 351 rtmsg_ifa(RTM_DELADDR, ifa, nlh, pid); 352 blocking_notifier_call_chain(&inetaddr_chain, 353 NETDEV_DOWN, ifa); 354 inet_free_ifa(ifa); 355 } else { 356 promote = ifa; 357 break; 358 } 359 } 360 } 361 362 /* On promotion all secondaries from subnet are changing 363 * the primary IP, we must remove all their routes silently 364 * and later to add them back with new prefsrc. Do this 365 * while all addresses are on the device list. 366 */ 367 for (ifa = promote; ifa; ifa = ifa->ifa_next) { 368 if (ifa1->ifa_mask == ifa->ifa_mask && 369 inet_ifa_match(ifa1->ifa_address, ifa)) 370 fib_del_ifaddr(ifa, ifa1); 371 } 372 373 /* 2. Unlink it */ 374 375 *ifap = ifa1->ifa_next; 376 inet_hash_remove(ifa1); 377 378 /* 3. Announce address deletion */ 379 380 /* Send message first, then call notifier. 381 At first sight, FIB update triggered by notifier 382 will refer to already deleted ifaddr, that could confuse 383 netlink listeners. It is not true: look, gated sees 384 that route deleted and if it still thinks that ifaddr 385 is valid, it will try to restore deleted routes... Grr. 386 So that, this order is correct. 387 */ 388 rtmsg_ifa(RTM_DELADDR, ifa1, nlh, pid); 389 blocking_notifier_call_chain(&inetaddr_chain, NETDEV_DOWN, ifa1); 390 391 if (promote) { 392 struct in_ifaddr *next_sec = promote->ifa_next; 393 394 if (prev_prom) { 395 prev_prom->ifa_next = promote->ifa_next; 396 promote->ifa_next = last_prim->ifa_next; 397 last_prim->ifa_next = promote; 398 } 399 400 promote->ifa_flags &= ~IFA_F_SECONDARY; 401 rtmsg_ifa(RTM_NEWADDR, promote, nlh, pid); 402 blocking_notifier_call_chain(&inetaddr_chain, 403 NETDEV_UP, promote); 404 for (ifa = next_sec; ifa; ifa = ifa->ifa_next) { 405 if (ifa1->ifa_mask != ifa->ifa_mask || 406 !inet_ifa_match(ifa1->ifa_address, ifa)) 407 continue; 408 fib_add_ifaddr(ifa); 409 } 410 411 } 412 if (destroy) 413 inet_free_ifa(ifa1); 414} 415 416static void inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap, 417 int destroy) 418{ 419 __inet_del_ifa(in_dev, ifap, destroy, NULL, 0); 420} 421 422static int __inet_insert_ifa(struct in_ifaddr *ifa, struct nlmsghdr *nlh, 423 u32 pid) 424{ 425 struct in_device *in_dev = ifa->ifa_dev; 426 struct in_ifaddr *ifa1, **ifap, **last_primary; 427 428 ASSERT_RTNL(); 429 430 if (!ifa->ifa_local) { 431 inet_free_ifa(ifa); 432 return 0; 433 } 434 435 ifa->ifa_flags &= ~IFA_F_SECONDARY; 436 last_primary = &in_dev->ifa_list; 437 438 for (ifap = &in_dev->ifa_list; (ifa1 = *ifap) != NULL; 439 ifap = &ifa1->ifa_next) { 440 if (!(ifa1->ifa_flags & IFA_F_SECONDARY) && 441 ifa->ifa_scope <= ifa1->ifa_scope) 442 last_primary = &ifa1->ifa_next; 443 if (ifa1->ifa_mask == ifa->ifa_mask && 444 inet_ifa_match(ifa1->ifa_address, ifa)) { 445 if (ifa1->ifa_local == ifa->ifa_local) { 446 inet_free_ifa(ifa); 447 return -EEXIST; 448 } 449 if (ifa1->ifa_scope != ifa->ifa_scope) { 450 inet_free_ifa(ifa); 451 return -EINVAL; 452 } 453 ifa->ifa_flags |= IFA_F_SECONDARY; 454 } 455 } 456 457 if (!(ifa->ifa_flags & IFA_F_SECONDARY)) { 458 net_srandom(ifa->ifa_local); 459 ifap = last_primary; 460 } 461 462 ifa->ifa_next = *ifap; 463 *ifap = ifa; 464 465 inet_hash_insert(dev_net(in_dev->dev), ifa); 466 467 /* Send message first, then call notifier. 468 Notifier will trigger FIB update, so that 469 listeners of netlink will know about new ifaddr */ 470 rtmsg_ifa(RTM_NEWADDR, ifa, nlh, pid); 471 blocking_notifier_call_chain(&inetaddr_chain, NETDEV_UP, ifa); 472 473 return 0; 474} 475 476static int inet_insert_ifa(struct in_ifaddr *ifa) 477{ 478 return __inet_insert_ifa(ifa, NULL, 0); 479} 480 481static int inet_set_ifa(struct net_device *dev, struct in_ifaddr *ifa) 482{ 483 struct in_device *in_dev = __in_dev_get_rtnl(dev); 484 485 ASSERT_RTNL(); 486 487 if (!in_dev) { 488 inet_free_ifa(ifa); 489 return -ENOBUFS; 490 } 491 ipv4_devconf_setall(in_dev); 492 if (ifa->ifa_dev != in_dev) { 493 WARN_ON(ifa->ifa_dev); 494 in_dev_hold(in_dev); 495 ifa->ifa_dev = in_dev; 496 } 497 if (ipv4_is_loopback(ifa->ifa_local)) 498 ifa->ifa_scope = RT_SCOPE_HOST; 499 return inet_insert_ifa(ifa); 500} 501 502/* Caller must hold RCU or RTNL : 503 * We dont take a reference on found in_device 504 */ 505struct in_device *inetdev_by_index(struct net *net, int ifindex) 506{ 507 struct net_device *dev; 508 struct in_device *in_dev = NULL; 509 510 rcu_read_lock(); 511 dev = dev_get_by_index_rcu(net, ifindex); 512 if (dev) 513 in_dev = rcu_dereference_rtnl(dev->ip_ptr); 514 rcu_read_unlock(); 515 return in_dev; 516} 517EXPORT_SYMBOL(inetdev_by_index); 518 519/* Called only from RTNL semaphored context. No locks. */ 520 521struct in_ifaddr *inet_ifa_byprefix(struct in_device *in_dev, __be32 prefix, 522 __be32 mask) 523{ 524 ASSERT_RTNL(); 525 526 for_primary_ifa(in_dev) { 527 if (ifa->ifa_mask == mask && inet_ifa_match(prefix, ifa)) 528 return ifa; 529 } endfor_ifa(in_dev); 530 return NULL; 531} 532 533static int inet_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg) 534{ 535 struct net *net = sock_net(skb->sk); 536 struct nlattr *tb[IFA_MAX+1]; 537 struct in_device *in_dev; 538 struct ifaddrmsg *ifm; 539 struct in_ifaddr *ifa, **ifap; 540 int err = -EINVAL; 541 542 ASSERT_RTNL(); 543 544 err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv4_policy); 545 if (err < 0) 546 goto errout; 547 548 ifm = nlmsg_data(nlh); 549 in_dev = inetdev_by_index(net, ifm->ifa_index); 550 if (in_dev == NULL) { 551 err = -ENODEV; 552 goto errout; 553 } 554 555 for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL; 556 ifap = &ifa->ifa_next) { 557 if (tb[IFA_LOCAL] && 558 ifa->ifa_local != nla_get_be32(tb[IFA_LOCAL])) 559 continue; 560 561 if (tb[IFA_LABEL] && nla_strcmp(tb[IFA_LABEL], ifa->ifa_label)) 562 continue; 563 564 if (tb[IFA_ADDRESS] && 565 (ifm->ifa_prefixlen != ifa->ifa_prefixlen || 566 !inet_ifa_match(nla_get_be32(tb[IFA_ADDRESS]), ifa))) 567 continue; 568 569 __inet_del_ifa(in_dev, ifap, 1, nlh, NETLINK_CB(skb).pid); 570 return 0; 571 } 572 573 err = -EADDRNOTAVAIL; 574errout: 575 return err; 576} 577 578static struct in_ifaddr *rtm_to_ifaddr(struct net *net, struct nlmsghdr *nlh) 579{ 580 struct nlattr *tb[IFA_MAX+1]; 581 struct in_ifaddr *ifa; 582 struct ifaddrmsg *ifm; 583 struct net_device *dev; 584 struct in_device *in_dev; 585 int err; 586 587 err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv4_policy); 588 if (err < 0) 589 goto errout; 590 591 ifm = nlmsg_data(nlh); 592 err = -EINVAL; 593 if (ifm->ifa_prefixlen > 32 || tb[IFA_LOCAL] == NULL) 594 goto errout; 595 596 dev = __dev_get_by_index(net, ifm->ifa_index); 597 err = -ENODEV; 598 if (dev == NULL) 599 goto errout; 600 601 in_dev = __in_dev_get_rtnl(dev); 602 err = -ENOBUFS; 603 if (in_dev == NULL) 604 goto errout; 605 606 ifa = inet_alloc_ifa(); 607 if (ifa == NULL) 608 /* 609 * A potential indev allocation can be left alive, it stays 610 * assigned to its device and is destroy with it. 611 */ 612 goto errout; 613 614 ipv4_devconf_setall(in_dev); 615 in_dev_hold(in_dev); 616 617 if (tb[IFA_ADDRESS] == NULL) 618 tb[IFA_ADDRESS] = tb[IFA_LOCAL]; 619 620 INIT_HLIST_NODE(&ifa->hash); 621 ifa->ifa_prefixlen = ifm->ifa_prefixlen; 622 ifa->ifa_mask = inet_make_mask(ifm->ifa_prefixlen); 623 ifa->ifa_flags = ifm->ifa_flags; 624 ifa->ifa_scope = ifm->ifa_scope; 625 ifa->ifa_dev = in_dev; 626 627 ifa->ifa_local = nla_get_be32(tb[IFA_LOCAL]); 628 ifa->ifa_address = nla_get_be32(tb[IFA_ADDRESS]); 629 630 if (tb[IFA_BROADCAST]) 631 ifa->ifa_broadcast = nla_get_be32(tb[IFA_BROADCAST]); 632 633 if (tb[IFA_LABEL]) 634 nla_strlcpy(ifa->ifa_label, tb[IFA_LABEL], IFNAMSIZ); 635 else 636 memcpy(ifa->ifa_label, dev->name, IFNAMSIZ); 637 638 return ifa; 639 640errout: 641 return ERR_PTR(err); 642} 643 644static int inet_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg) 645{ 646 struct net *net = sock_net(skb->sk); 647 struct in_ifaddr *ifa; 648 649 ASSERT_RTNL(); 650 651 ifa = rtm_to_ifaddr(net, nlh); 652 if (IS_ERR(ifa)) 653 return PTR_ERR(ifa); 654 655 return __inet_insert_ifa(ifa, nlh, NETLINK_CB(skb).pid); 656} 657 658/* 659 * Determine a default network mask, based on the IP address. 660 */ 661 662static inline int inet_abc_len(__be32 addr) 663{ 664 int rc = -1; /* Something else, probably a multicast. */ 665 666 if (ipv4_is_zeronet(addr)) 667 rc = 0; 668 else { 669 __u32 haddr = ntohl(addr); 670 671 if (IN_CLASSA(haddr)) 672 rc = 8; 673 else if (IN_CLASSB(haddr)) 674 rc = 16; 675 else if (IN_CLASSC(haddr)) 676 rc = 24; 677 } 678 679 return rc; 680} 681 682 683int devinet_ioctl(struct net *net, unsigned int cmd, void __user *arg) 684{ 685 struct ifreq ifr; 686 struct sockaddr_in sin_orig; 687 struct sockaddr_in *sin = (struct sockaddr_in *)&ifr.ifr_addr; 688 struct in_device *in_dev; 689 struct in_ifaddr **ifap = NULL; 690 struct in_ifaddr *ifa = NULL; 691 struct net_device *dev; 692 char *colon; 693 int ret = -EFAULT; 694 int tryaddrmatch = 0; 695 696 /* 697 * Fetch the caller's info block into kernel space 698 */ 699 700 if (copy_from_user(&ifr, arg, sizeof(struct ifreq))) 701 goto out; 702 ifr.ifr_name[IFNAMSIZ - 1] = 0; 703 704 /* save original address for comparison */ 705 memcpy(&sin_orig, sin, sizeof(*sin)); 706 707 colon = strchr(ifr.ifr_name, ':'); 708 if (colon) 709 *colon = 0; 710 711 dev_load(net, ifr.ifr_name); 712 713 switch (cmd) { 714 case SIOCGIFADDR: /* Get interface address */ 715 case SIOCGIFBRDADDR: /* Get the broadcast address */ 716 case SIOCGIFDSTADDR: /* Get the destination address */ 717 case SIOCGIFNETMASK: /* Get the netmask for the interface */ 718 /* Note that these ioctls will not sleep, 719 so that we do not impose a lock. 720 One day we will be forced to put shlock here (I mean SMP) 721 */ 722 tryaddrmatch = (sin_orig.sin_family == AF_INET); 723 memset(sin, 0, sizeof(*sin)); 724 sin->sin_family = AF_INET; 725 break; 726 727 case SIOCSIFFLAGS: 728 ret = -EACCES; 729 if (!capable(CAP_NET_ADMIN)) 730 goto out; 731 break; 732 case SIOCSIFADDR: /* Set interface address (and family) */ 733 case SIOCSIFBRDADDR: /* Set the broadcast address */ 734 case SIOCSIFDSTADDR: /* Set the destination address */ 735 case SIOCSIFNETMASK: /* Set the netmask for the interface */ 736 ret = -EACCES; 737 if (!capable(CAP_NET_ADMIN)) 738 goto out; 739 ret = -EINVAL; 740 if (sin->sin_family != AF_INET) 741 goto out; 742 break; 743 default: 744 ret = -EINVAL; 745 goto out; 746 } 747 748 rtnl_lock(); 749 750 ret = -ENODEV; 751 dev = __dev_get_by_name(net, ifr.ifr_name); 752 if (!dev) 753 goto done; 754 755 if (colon) 756 *colon = ':'; 757 758 in_dev = __in_dev_get_rtnl(dev); 759 if (in_dev) { 760 if (tryaddrmatch) { 761 /* Matthias Andree */ 762 /* compare label and address (4.4BSD style) */ 763 /* note: we only do this for a limited set of ioctls 764 and only if the original address family was AF_INET. 765 This is checked above. */ 766 for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL; 767 ifap = &ifa->ifa_next) { 768 if (!strcmp(ifr.ifr_name, ifa->ifa_label) && 769 sin_orig.sin_addr.s_addr == 770 ifa->ifa_local) { 771 break; /* found */ 772 } 773 } 774 } 775 /* we didn't get a match, maybe the application is 776 4.3BSD-style and passed in junk so we fall back to 777 comparing just the label */ 778 if (!ifa) { 779 for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL; 780 ifap = &ifa->ifa_next) 781 if (!strcmp(ifr.ifr_name, ifa->ifa_label)) 782 break; 783 } 784 } 785 786 ret = -EADDRNOTAVAIL; 787 if (!ifa && cmd != SIOCSIFADDR && cmd != SIOCSIFFLAGS) 788 goto done; 789 790 switch (cmd) { 791 case SIOCGIFADDR: /* Get interface address */ 792 sin->sin_addr.s_addr = ifa->ifa_local; 793 goto rarok; 794 795 case SIOCGIFBRDADDR: /* Get the broadcast address */ 796 sin->sin_addr.s_addr = ifa->ifa_broadcast; 797 goto rarok; 798 799 case SIOCGIFDSTADDR: /* Get the destination address */ 800 sin->sin_addr.s_addr = ifa->ifa_address; 801 goto rarok; 802 803 case SIOCGIFNETMASK: /* Get the netmask for the interface */ 804 sin->sin_addr.s_addr = ifa->ifa_mask; 805 goto rarok; 806 807 case SIOCSIFFLAGS: 808 if (colon) { 809 ret = -EADDRNOTAVAIL; 810 if (!ifa) 811 break; 812 ret = 0; 813 if (!(ifr.ifr_flags & IFF_UP)) 814 inet_del_ifa(in_dev, ifap, 1); 815 break; 816 } 817 ret = dev_change_flags(dev, ifr.ifr_flags); 818 break; 819 820 case SIOCSIFADDR: /* Set interface address (and family) */ 821 ret = -EINVAL; 822 if (inet_abc_len(sin->sin_addr.s_addr) < 0) 823 break; 824 825 if (!ifa) { 826 ret = -ENOBUFS; 827 ifa = inet_alloc_ifa(); 828 INIT_HLIST_NODE(&ifa->hash); 829 if (!ifa) 830 break; 831 if (colon) 832 memcpy(ifa->ifa_label, ifr.ifr_name, IFNAMSIZ); 833 else 834 memcpy(ifa->ifa_label, dev->name, IFNAMSIZ); 835 } else { 836 ret = 0; 837 if (ifa->ifa_local == sin->sin_addr.s_addr) 838 break; 839 inet_del_ifa(in_dev, ifap, 0); 840 ifa->ifa_broadcast = 0; 841 ifa->ifa_scope = 0; 842 } 843 844 ifa->ifa_address = ifa->ifa_local = sin->sin_addr.s_addr; 845 846 if (!(dev->flags & IFF_POINTOPOINT)) { 847 ifa->ifa_prefixlen = inet_abc_len(ifa->ifa_address); 848 ifa->ifa_mask = inet_make_mask(ifa->ifa_prefixlen); 849 if ((dev->flags & IFF_BROADCAST) && 850 ifa->ifa_prefixlen < 31) 851 ifa->ifa_broadcast = ifa->ifa_address | 852 ~ifa->ifa_mask; 853 } else { 854 ifa->ifa_prefixlen = 32; 855 ifa->ifa_mask = inet_make_mask(32); 856 } 857 ret = inet_set_ifa(dev, ifa); 858 break; 859 860 case SIOCSIFBRDADDR: /* Set the broadcast address */ 861 ret = 0; 862 if (ifa->ifa_broadcast != sin->sin_addr.s_addr) { 863 inet_del_ifa(in_dev, ifap, 0); 864 ifa->ifa_broadcast = sin->sin_addr.s_addr; 865 inet_insert_ifa(ifa); 866 } 867 break; 868 869 case SIOCSIFDSTADDR: /* Set the destination address */ 870 ret = 0; 871 if (ifa->ifa_address == sin->sin_addr.s_addr) 872 break; 873 ret = -EINVAL; 874 if (inet_abc_len(sin->sin_addr.s_addr) < 0) 875 break; 876 ret = 0; 877 inet_del_ifa(in_dev, ifap, 0); 878 ifa->ifa_address = sin->sin_addr.s_addr; 879 inet_insert_ifa(ifa); 880 break; 881 882 case SIOCSIFNETMASK: /* Set the netmask for the interface */ 883 884 /* 885 * The mask we set must be legal. 886 */ 887 ret = -EINVAL; 888 if (bad_mask(sin->sin_addr.s_addr, 0)) 889 break; 890 ret = 0; 891 if (ifa->ifa_mask != sin->sin_addr.s_addr) { 892 __be32 old_mask = ifa->ifa_mask; 893 inet_del_ifa(in_dev, ifap, 0); 894 ifa->ifa_mask = sin->sin_addr.s_addr; 895 ifa->ifa_prefixlen = inet_mask_len(ifa->ifa_mask); 896 897 /* See if current broadcast address matches 898 * with current netmask, then recalculate 899 * the broadcast address. Otherwise it's a 900 * funny address, so don't touch it since 901 * the user seems to know what (s)he's doing... 902 */ 903 if ((dev->flags & IFF_BROADCAST) && 904 (ifa->ifa_prefixlen < 31) && 905 (ifa->ifa_broadcast == 906 (ifa->ifa_local|~old_mask))) { 907 ifa->ifa_broadcast = (ifa->ifa_local | 908 ~sin->sin_addr.s_addr); 909 } 910 inet_insert_ifa(ifa); 911 } 912 break; 913 } 914done: 915 rtnl_unlock(); 916out: 917 return ret; 918rarok: 919 rtnl_unlock(); 920 ret = copy_to_user(arg, &ifr, sizeof(struct ifreq)) ? -EFAULT : 0; 921 goto out; 922} 923 924static int inet_gifconf(struct net_device *dev, char __user *buf, int len) 925{ 926 struct in_device *in_dev = __in_dev_get_rtnl(dev); 927 struct in_ifaddr *ifa; 928 struct ifreq ifr; 929 int done = 0; 930 931 if (!in_dev) 932 goto out; 933 934 for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) { 935 if (!buf) { 936 done += sizeof(ifr); 937 continue; 938 } 939 if (len < (int) sizeof(ifr)) 940 break; 941 memset(&ifr, 0, sizeof(struct ifreq)); 942 if (ifa->ifa_label) 943 strcpy(ifr.ifr_name, ifa->ifa_label); 944 else 945 strcpy(ifr.ifr_name, dev->name); 946 947 (*(struct sockaddr_in *)&ifr.ifr_addr).sin_family = AF_INET; 948 (*(struct sockaddr_in *)&ifr.ifr_addr).sin_addr.s_addr = 949 ifa->ifa_local; 950 951 if (copy_to_user(buf, &ifr, sizeof(struct ifreq))) { 952 done = -EFAULT; 953 break; 954 } 955 buf += sizeof(struct ifreq); 956 len -= sizeof(struct ifreq); 957 done += sizeof(struct ifreq); 958 } 959out: 960 return done; 961} 962 963__be32 inet_select_addr(const struct net_device *dev, __be32 dst, int scope) 964{ 965 __be32 addr = 0; 966 struct in_device *in_dev; 967 struct net *net = dev_net(dev); 968 969 rcu_read_lock(); 970 in_dev = __in_dev_get_rcu(dev); 971 if (!in_dev) 972 goto no_in_dev; 973 974 for_primary_ifa(in_dev) { 975 if (ifa->ifa_scope > scope) 976 continue; 977 if (!dst || inet_ifa_match(dst, ifa)) { 978 addr = ifa->ifa_local; 979 break; 980 } 981 if (!addr) 982 addr = ifa->ifa_local; 983 } endfor_ifa(in_dev); 984 985 if (addr) 986 goto out_unlock; 987no_in_dev: 988 989 /* Not loopback addresses on loopback should be preferred 990 in this case. It is importnat that lo is the first interface 991 in dev_base list. 992 */ 993 for_each_netdev_rcu(net, dev) { 994 in_dev = __in_dev_get_rcu(dev); 995 if (!in_dev) 996 continue; 997 998 for_primary_ifa(in_dev) { 999 if (ifa->ifa_scope != RT_SCOPE_LINK && 1000 ifa->ifa_scope <= scope) { 1001 addr = ifa->ifa_local; 1002 goto out_unlock; 1003 } 1004 } endfor_ifa(in_dev); 1005 } 1006out_unlock: 1007 rcu_read_unlock(); 1008 return addr; 1009} 1010EXPORT_SYMBOL(inet_select_addr); 1011 1012static __be32 confirm_addr_indev(struct in_device *in_dev, __be32 dst, 1013 __be32 local, int scope) 1014{ 1015 int same = 0; 1016 __be32 addr = 0; 1017 1018 for_ifa(in_dev) { 1019 if (!addr && 1020 (local == ifa->ifa_local || !local) && 1021 ifa->ifa_scope <= scope) { 1022 addr = ifa->ifa_local; 1023 if (same) 1024 break; 1025 } 1026 if (!same) { 1027 same = (!local || inet_ifa_match(local, ifa)) && 1028 (!dst || inet_ifa_match(dst, ifa)); 1029 if (same && addr) { 1030 if (local || !dst) 1031 break; 1032 /* Is the selected addr into dst subnet? */ 1033 if (inet_ifa_match(addr, ifa)) 1034 break; 1035 /* No, then can we use new local src? */ 1036 if (ifa->ifa_scope <= scope) { 1037 addr = ifa->ifa_local; 1038 break; 1039 } 1040 /* search for large dst subnet for addr */ 1041 same = 0; 1042 } 1043 } 1044 } endfor_ifa(in_dev); 1045 1046 return same ? addr : 0; 1047} 1048 1049/* 1050 * Confirm that local IP address exists using wildcards: 1051 * - in_dev: only on this interface, 0=any interface 1052 * - dst: only in the same subnet as dst, 0=any dst 1053 * - local: address, 0=autoselect the local address 1054 * - scope: maximum allowed scope value for the local address 1055 */ 1056__be32 inet_confirm_addr(struct in_device *in_dev, 1057 __be32 dst, __be32 local, int scope) 1058{ 1059 __be32 addr = 0; 1060 struct net_device *dev; 1061 struct net *net; 1062 1063 if (scope != RT_SCOPE_LINK) 1064 return confirm_addr_indev(in_dev, dst, local, scope); 1065 1066 net = dev_net(in_dev->dev); 1067 rcu_read_lock(); 1068 for_each_netdev_rcu(net, dev) { 1069 in_dev = __in_dev_get_rcu(dev); 1070 if (in_dev) { 1071 addr = confirm_addr_indev(in_dev, dst, local, scope); 1072 if (addr) 1073 break; 1074 } 1075 } 1076 rcu_read_unlock(); 1077 1078 return addr; 1079} 1080EXPORT_SYMBOL(inet_confirm_addr); 1081 1082/* 1083 * Device notifier 1084 */ 1085 1086int register_inetaddr_notifier(struct notifier_block *nb) 1087{ 1088 return blocking_notifier_chain_register(&inetaddr_chain, nb); 1089} 1090EXPORT_SYMBOL(register_inetaddr_notifier); 1091 1092int unregister_inetaddr_notifier(struct notifier_block *nb) 1093{ 1094 return blocking_notifier_chain_unregister(&inetaddr_chain, nb); 1095} 1096EXPORT_SYMBOL(unregister_inetaddr_notifier); 1097 1098/* Rename ifa_labels for a device name change. Make some effort to preserve 1099 * existing alias numbering and to create unique labels if possible. 1100*/ 1101static void inetdev_changename(struct net_device *dev, struct in_device *in_dev) 1102{ 1103 struct in_ifaddr *ifa; 1104 int named = 0; 1105 1106 for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) { 1107 char old[IFNAMSIZ], *dot; 1108 1109 memcpy(old, ifa->ifa_label, IFNAMSIZ); 1110 memcpy(ifa->ifa_label, dev->name, IFNAMSIZ); 1111 if (named++ == 0) 1112 goto skip; 1113 dot = strchr(old, ':'); 1114 if (dot == NULL) { 1115 sprintf(old, ":%d", named); 1116 dot = old; 1117 } 1118 if (strlen(dot) + strlen(dev->name) < IFNAMSIZ) 1119 strcat(ifa->ifa_label, dot); 1120 else 1121 strcpy(ifa->ifa_label + (IFNAMSIZ - strlen(dot) - 1), dot); 1122skip: 1123 rtmsg_ifa(RTM_NEWADDR, ifa, NULL, 0); 1124 } 1125} 1126 1127static inline bool inetdev_valid_mtu(unsigned int mtu) 1128{ 1129 return mtu >= 68; 1130} 1131 1132static void inetdev_send_gratuitous_arp(struct net_device *dev, 1133 struct in_device *in_dev) 1134 1135{ 1136 struct in_ifaddr *ifa; 1137 1138 for (ifa = in_dev->ifa_list; ifa; 1139 ifa = ifa->ifa_next) { 1140 arp_send(ARPOP_REQUEST, ETH_P_ARP, 1141 ifa->ifa_local, dev, 1142 ifa->ifa_local, NULL, 1143 dev->dev_addr, NULL); 1144 } 1145} 1146 1147/* Called only under RTNL semaphore */ 1148 1149static int inetdev_event(struct notifier_block *this, unsigned long event, 1150 void *ptr) 1151{ 1152 struct net_device *dev = ptr; 1153 struct in_device *in_dev = __in_dev_get_rtnl(dev); 1154 1155 ASSERT_RTNL(); 1156 1157 if (!in_dev) { 1158 if (event == NETDEV_REGISTER) { 1159 in_dev = inetdev_init(dev); 1160 if (!in_dev) 1161 return notifier_from_errno(-ENOMEM); 1162 if (dev->flags & IFF_LOOPBACK) { 1163 IN_DEV_CONF_SET(in_dev, NOXFRM, 1); 1164 IN_DEV_CONF_SET(in_dev, NOPOLICY, 1); 1165 } 1166 } else if (event == NETDEV_CHANGEMTU) { 1167 /* Re-enabling IP */ 1168 if (inetdev_valid_mtu(dev->mtu)) 1169 in_dev = inetdev_init(dev); 1170 } 1171 goto out; 1172 } 1173 1174 switch (event) { 1175 case NETDEV_REGISTER: 1176 pr_debug("%s: bug\n", __func__); 1177 RCU_INIT_POINTER(dev->ip_ptr, NULL); 1178 break; 1179 case NETDEV_UP: 1180 if (!inetdev_valid_mtu(dev->mtu)) 1181 break; 1182 if (dev->flags & IFF_LOOPBACK) { 1183 struct in_ifaddr *ifa = inet_alloc_ifa(); 1184 1185 if (ifa) { 1186 INIT_HLIST_NODE(&ifa->hash); 1187 ifa->ifa_local = 1188 ifa->ifa_address = htonl(INADDR_LOOPBACK); 1189 ifa->ifa_prefixlen = 8; 1190 ifa->ifa_mask = inet_make_mask(8); 1191 in_dev_hold(in_dev); 1192 ifa->ifa_dev = in_dev; 1193 ifa->ifa_scope = RT_SCOPE_HOST; 1194 memcpy(ifa->ifa_label, dev->name, IFNAMSIZ); 1195 inet_insert_ifa(ifa); 1196 } 1197 } 1198 ip_mc_up(in_dev); 1199 /* fall through */ 1200 case NETDEV_CHANGEADDR: 1201 if (!IN_DEV_ARP_NOTIFY(in_dev)) 1202 break; 1203 /* fall through */ 1204 case NETDEV_NOTIFY_PEERS: 1205 /* Send gratuitous ARP to notify of link change */ 1206 inetdev_send_gratuitous_arp(dev, in_dev); 1207 break; 1208 case NETDEV_DOWN: 1209 ip_mc_down(in_dev); 1210 break; 1211 case NETDEV_PRE_TYPE_CHANGE: 1212 ip_mc_unmap(in_dev); 1213 break; 1214 case NETDEV_POST_TYPE_CHANGE: 1215 ip_mc_remap(in_dev); 1216 break; 1217 case NETDEV_CHANGEMTU: 1218 if (inetdev_valid_mtu(dev->mtu)) 1219 break; 1220 /* disable IP when MTU is not enough */ 1221 case NETDEV_UNREGISTER: 1222 inetdev_destroy(in_dev); 1223 break; 1224 case NETDEV_CHANGENAME: 1225 /* Do not notify about label change, this event is 1226 * not interesting to applications using netlink. 1227 */ 1228 inetdev_changename(dev, in_dev); 1229 1230 devinet_sysctl_unregister(in_dev); 1231 devinet_sysctl_register(in_dev); 1232 break; 1233 } 1234out: 1235 return NOTIFY_DONE; 1236} 1237 1238static struct notifier_block ip_netdev_notifier = { 1239 .notifier_call = inetdev_event, 1240}; 1241 1242static inline size_t inet_nlmsg_size(void) 1243{ 1244 return NLMSG_ALIGN(sizeof(struct ifaddrmsg)) 1245 + nla_total_size(4) /* IFA_ADDRESS */ 1246 + nla_total_size(4) /* IFA_LOCAL */ 1247 + nla_total_size(4) /* IFA_BROADCAST */ 1248 + nla_total_size(IFNAMSIZ); /* IFA_LABEL */ 1249} 1250 1251static int inet_fill_ifaddr(struct sk_buff *skb, struct in_ifaddr *ifa, 1252 u32 pid, u32 seq, int event, unsigned int flags) 1253{ 1254 struct ifaddrmsg *ifm; 1255 struct nlmsghdr *nlh; 1256 1257 nlh = nlmsg_put(skb, pid, seq, event, sizeof(*ifm), flags); 1258 if (nlh == NULL) 1259 return -EMSGSIZE; 1260 1261 ifm = nlmsg_data(nlh); 1262 ifm->ifa_family = AF_INET; 1263 ifm->ifa_prefixlen = ifa->ifa_prefixlen; 1264 ifm->ifa_flags = ifa->ifa_flags|IFA_F_PERMANENT; 1265 ifm->ifa_scope = ifa->ifa_scope; 1266 ifm->ifa_index = ifa->ifa_dev->dev->ifindex; 1267 1268 if ((ifa->ifa_address && 1269 nla_put_be32(skb, IFA_ADDRESS, ifa->ifa_address)) || 1270 (ifa->ifa_local && 1271 nla_put_be32(skb, IFA_LOCAL, ifa->ifa_local)) || 1272 (ifa->ifa_broadcast && 1273 nla_put_be32(skb, IFA_BROADCAST, ifa->ifa_broadcast)) || 1274 (ifa->ifa_label[0] && 1275 nla_put_string(skb, IFA_LABEL, ifa->ifa_label))) 1276 goto nla_put_failure; 1277 1278 return nlmsg_end(skb, nlh); 1279 1280nla_put_failure: 1281 nlmsg_cancel(skb, nlh); 1282 return -EMSGSIZE; 1283} 1284 1285static int inet_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb) 1286{ 1287 struct net *net = sock_net(skb->sk); 1288 int h, s_h; 1289 int idx, s_idx; 1290 int ip_idx, s_ip_idx; 1291 struct net_device *dev; 1292 struct in_device *in_dev; 1293 struct in_ifaddr *ifa; 1294 struct hlist_head *head; 1295 struct hlist_node *node; 1296 1297 s_h = cb->args[0]; 1298 s_idx = idx = cb->args[1]; 1299 s_ip_idx = ip_idx = cb->args[2]; 1300 1301 for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) { 1302 idx = 0; 1303 head = &net->dev_index_head[h]; 1304 rcu_read_lock(); 1305 hlist_for_each_entry_rcu(dev, node, head, index_hlist) { 1306 if (idx < s_idx) 1307 goto cont; 1308 if (h > s_h || idx > s_idx) 1309 s_ip_idx = 0; 1310 in_dev = __in_dev_get_rcu(dev); 1311 if (!in_dev) 1312 goto cont; 1313 1314 for (ifa = in_dev->ifa_list, ip_idx = 0; ifa; 1315 ifa = ifa->ifa_next, ip_idx++) { 1316 if (ip_idx < s_ip_idx) 1317 continue; 1318 if (inet_fill_ifaddr(skb, ifa, 1319 NETLINK_CB(cb->skb).pid, 1320 cb->nlh->nlmsg_seq, 1321 RTM_NEWADDR, NLM_F_MULTI) <= 0) { 1322 rcu_read_unlock(); 1323 goto done; 1324 } 1325 } 1326cont: 1327 idx++; 1328 } 1329 rcu_read_unlock(); 1330 } 1331 1332done: 1333 cb->args[0] = h; 1334 cb->args[1] = idx; 1335 cb->args[2] = ip_idx; 1336 1337 return skb->len; 1338} 1339 1340static void rtmsg_ifa(int event, struct in_ifaddr *ifa, struct nlmsghdr *nlh, 1341 u32 pid) 1342{ 1343 struct sk_buff *skb; 1344 u32 seq = nlh ? nlh->nlmsg_seq : 0; 1345 int err = -ENOBUFS; 1346 struct net *net; 1347 1348 net = dev_net(ifa->ifa_dev->dev); 1349 skb = nlmsg_new(inet_nlmsg_size(), GFP_KERNEL); 1350 if (skb == NULL) 1351 goto errout; 1352 1353 err = inet_fill_ifaddr(skb, ifa, pid, seq, event, 0); 1354 if (err < 0) { 1355 /* -EMSGSIZE implies BUG in inet_nlmsg_size() */ 1356 WARN_ON(err == -EMSGSIZE); 1357 kfree_skb(skb); 1358 goto errout; 1359 } 1360 rtnl_notify(skb, net, pid, RTNLGRP_IPV4_IFADDR, nlh, GFP_KERNEL); 1361 return; 1362errout: 1363 if (err < 0) 1364 rtnl_set_sk_err(net, RTNLGRP_IPV4_IFADDR, err); 1365} 1366 1367static size_t inet_get_link_af_size(const struct net_device *dev) 1368{ 1369 struct in_device *in_dev = rcu_dereference_rtnl(dev->ip_ptr); 1370 1371 if (!in_dev) 1372 return 0; 1373 1374 return nla_total_size(IPV4_DEVCONF_MAX * 4); /* IFLA_INET_CONF */ 1375} 1376 1377static int inet_fill_link_af(struct sk_buff *skb, const struct net_device *dev) 1378{ 1379 struct in_device *in_dev = rcu_dereference_rtnl(dev->ip_ptr); 1380 struct nlattr *nla; 1381 int i; 1382 1383 if (!in_dev) 1384 return -ENODATA; 1385 1386 nla = nla_reserve(skb, IFLA_INET_CONF, IPV4_DEVCONF_MAX * 4); 1387 if (nla == NULL) 1388 return -EMSGSIZE; 1389 1390 for (i = 0; i < IPV4_DEVCONF_MAX; i++) 1391 ((u32 *) nla_data(nla))[i] = in_dev->cnf.data[i]; 1392 1393 return 0; 1394} 1395 1396static const struct nla_policy inet_af_policy[IFLA_INET_MAX+1] = { 1397 [IFLA_INET_CONF] = { .type = NLA_NESTED }, 1398}; 1399 1400static int inet_validate_link_af(const struct net_device *dev, 1401 const struct nlattr *nla) 1402{ 1403 struct nlattr *a, *tb[IFLA_INET_MAX+1]; 1404 int err, rem; 1405 1406 if (dev && !__in_dev_get_rtnl(dev)) 1407 return -EAFNOSUPPORT; 1408 1409 err = nla_parse_nested(tb, IFLA_INET_MAX, nla, inet_af_policy); 1410 if (err < 0) 1411 return err; 1412 1413 if (tb[IFLA_INET_CONF]) { 1414 nla_for_each_nested(a, tb[IFLA_INET_CONF], rem) { 1415 int cfgid = nla_type(a); 1416 1417 if (nla_len(a) < 4) 1418 return -EINVAL; 1419 1420 if (cfgid <= 0 || cfgid > IPV4_DEVCONF_MAX) 1421 return -EINVAL; 1422 } 1423 } 1424 1425 return 0; 1426} 1427 1428static int inet_set_link_af(struct net_device *dev, const struct nlattr *nla) 1429{ 1430 struct in_device *in_dev = __in_dev_get_rtnl(dev); 1431 struct nlattr *a, *tb[IFLA_INET_MAX+1]; 1432 int rem; 1433 1434 if (!in_dev) 1435 return -EAFNOSUPPORT; 1436 1437 if (nla_parse_nested(tb, IFLA_INET_MAX, nla, NULL) < 0) 1438 BUG(); 1439 1440 if (tb[IFLA_INET_CONF]) { 1441 nla_for_each_nested(a, tb[IFLA_INET_CONF], rem) 1442 ipv4_devconf_set(in_dev, nla_type(a), nla_get_u32(a)); 1443 } 1444 1445 return 0; 1446} 1447 1448#ifdef CONFIG_SYSCTL 1449 1450static void devinet_copy_dflt_conf(struct net *net, int i) 1451{ 1452 struct net_device *dev; 1453 1454 rcu_read_lock(); 1455 for_each_netdev_rcu(net, dev) { 1456 struct in_device *in_dev; 1457 1458 in_dev = __in_dev_get_rcu(dev); 1459 if (in_dev && !test_bit(i, in_dev->cnf.state)) 1460 in_dev->cnf.data[i] = net->ipv4.devconf_dflt->data[i]; 1461 } 1462 rcu_read_unlock(); 1463} 1464 1465/* called with RTNL locked */ 1466static void inet_forward_change(struct net *net) 1467{ 1468 struct net_device *dev; 1469 int on = IPV4_DEVCONF_ALL(net, FORWARDING); 1470 1471 IPV4_DEVCONF_ALL(net, ACCEPT_REDIRECTS) = !on; 1472 IPV4_DEVCONF_DFLT(net, FORWARDING) = on; 1473 1474 for_each_netdev(net, dev) { 1475 struct in_device *in_dev; 1476 if (on) 1477 dev_disable_lro(dev); 1478 rcu_read_lock(); 1479 in_dev = __in_dev_get_rcu(dev); 1480 if (in_dev) 1481 IN_DEV_CONF_SET(in_dev, FORWARDING, on); 1482 rcu_read_unlock(); 1483 } 1484} 1485 1486static int devinet_conf_proc(ctl_table *ctl, int write, 1487 void __user *buffer, 1488 size_t *lenp, loff_t *ppos) 1489{ 1490 int old_value = *(int *)ctl->data; 1491 int ret = proc_dointvec(ctl, write, buffer, lenp, ppos); 1492 int new_value = *(int *)ctl->data; 1493 1494 if (write) { 1495 struct ipv4_devconf *cnf = ctl->extra1; 1496 struct net *net = ctl->extra2; 1497 int i = (int *)ctl->data - cnf->data; 1498 1499 set_bit(i, cnf->state); 1500 1501 if (cnf == net->ipv4.devconf_dflt) 1502 devinet_copy_dflt_conf(net, i); 1503 if (i == IPV4_DEVCONF_ACCEPT_LOCAL - 1) 1504 if ((new_value == 0) && (old_value != 0)) 1505 rt_cache_flush(net, 0); 1506 } 1507 1508 return ret; 1509} 1510 1511static int devinet_sysctl_forward(ctl_table *ctl, int write, 1512 void __user *buffer, 1513 size_t *lenp, loff_t *ppos) 1514{ 1515 int *valp = ctl->data; 1516 int val = *valp; 1517 loff_t pos = *ppos; 1518 int ret = proc_dointvec(ctl, write, buffer, lenp, ppos); 1519 1520 if (write && *valp != val) { 1521 struct net *net = ctl->extra2; 1522 1523 if (valp != &IPV4_DEVCONF_DFLT(net, FORWARDING)) { 1524 if (!rtnl_trylock()) { 1525 /* Restore the original values before restarting */ 1526 *valp = val; 1527 *ppos = pos; 1528 return restart_syscall(); 1529 } 1530 if (valp == &IPV4_DEVCONF_ALL(net, FORWARDING)) { 1531 inet_forward_change(net); 1532 } else if (*valp) { 1533 struct ipv4_devconf *cnf = ctl->extra1; 1534 struct in_device *idev = 1535 container_of(cnf, struct in_device, cnf); 1536 dev_disable_lro(idev->dev); 1537 } 1538 rtnl_unlock(); 1539 rt_cache_flush(net, 0); 1540 } 1541 } 1542 1543 return ret; 1544} 1545 1546static int ipv4_doint_and_flush(ctl_table *ctl, int write, 1547 void __user *buffer, 1548 size_t *lenp, loff_t *ppos) 1549{ 1550 int *valp = ctl->data; 1551 int val = *valp; 1552 int ret = proc_dointvec(ctl, write, buffer, lenp, ppos); 1553 struct net *net = ctl->extra2; 1554 1555 if (write && *valp != val) 1556 rt_cache_flush(net, 0); 1557 1558 return ret; 1559} 1560 1561#define DEVINET_SYSCTL_ENTRY(attr, name, mval, proc) \ 1562 { \ 1563 .procname = name, \ 1564 .data = ipv4_devconf.data + \ 1565 IPV4_DEVCONF_ ## attr - 1, \ 1566 .maxlen = sizeof(int), \ 1567 .mode = mval, \ 1568 .proc_handler = proc, \ 1569 .extra1 = &ipv4_devconf, \ 1570 } 1571 1572#define DEVINET_SYSCTL_RW_ENTRY(attr, name) \ 1573 DEVINET_SYSCTL_ENTRY(attr, name, 0644, devinet_conf_proc) 1574 1575#define DEVINET_SYSCTL_RO_ENTRY(attr, name) \ 1576 DEVINET_SYSCTL_ENTRY(attr, name, 0444, devinet_conf_proc) 1577 1578#define DEVINET_SYSCTL_COMPLEX_ENTRY(attr, name, proc) \ 1579 DEVINET_SYSCTL_ENTRY(attr, name, 0644, proc) 1580 1581#define DEVINET_SYSCTL_FLUSHING_ENTRY(attr, name) \ 1582 DEVINET_SYSCTL_COMPLEX_ENTRY(attr, name, ipv4_doint_and_flush) 1583 1584static struct devinet_sysctl_table { 1585 struct ctl_table_header *sysctl_header; 1586 struct ctl_table devinet_vars[__IPV4_DEVCONF_MAX]; 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 char path[sizeof("net/ipv4/conf/") + IFNAMSIZ]; 1629 1630 t = kmemdup(&devinet_sysctl, sizeof(*t), GFP_KERNEL); 1631 if (!t) 1632 goto out; 1633 1634 for (i = 0; i < ARRAY_SIZE(t->devinet_vars) - 1; i++) { 1635 t->devinet_vars[i].data += (char *)p - (char *)&ipv4_devconf; 1636 t->devinet_vars[i].extra1 = p; 1637 t->devinet_vars[i].extra2 = net; 1638 } 1639 1640 snprintf(path, sizeof(path), "net/ipv4/conf/%s", dev_name); 1641 1642 t->sysctl_header = register_net_sysctl(net, path, t->devinet_vars); 1643 if (!t->sysctl_header) 1644 goto free; 1645 1646 p->sysctl = t; 1647 return 0; 1648 1649free: 1650 kfree(t); 1651out: 1652 return -ENOBUFS; 1653} 1654 1655static void __devinet_sysctl_unregister(struct ipv4_devconf *cnf) 1656{ 1657 struct devinet_sysctl_table *t = cnf->sysctl; 1658 1659 if (t == NULL) 1660 return; 1661 1662 cnf->sysctl = NULL; 1663 unregister_net_sysctl_table(t->sysctl_header); 1664 kfree(t); 1665} 1666 1667static void devinet_sysctl_register(struct in_device *idev) 1668{ 1669 neigh_sysctl_register(idev->dev, idev->arp_parms, "ipv4", NULL); 1670 __devinet_sysctl_register(dev_net(idev->dev), idev->dev->name, 1671 &idev->cnf); 1672} 1673 1674static void devinet_sysctl_unregister(struct in_device *idev) 1675{ 1676 __devinet_sysctl_unregister(&idev->cnf); 1677 neigh_sysctl_unregister(idev->arp_parms); 1678} 1679 1680static struct ctl_table ctl_forward_entry[] = { 1681 { 1682 .procname = "ip_forward", 1683 .data = &ipv4_devconf.data[ 1684 IPV4_DEVCONF_FORWARDING - 1], 1685 .maxlen = sizeof(int), 1686 .mode = 0644, 1687 .proc_handler = devinet_sysctl_forward, 1688 .extra1 = &ipv4_devconf, 1689 .extra2 = &init_net, 1690 }, 1691 { }, 1692}; 1693#endif 1694 1695static __net_init int devinet_init_net(struct net *net) 1696{ 1697 int err; 1698 struct ipv4_devconf *all, *dflt; 1699#ifdef CONFIG_SYSCTL 1700 struct ctl_table *tbl = ctl_forward_entry; 1701 struct ctl_table_header *forw_hdr; 1702#endif 1703 1704 err = -ENOMEM; 1705 all = &ipv4_devconf; 1706 dflt = &ipv4_devconf_dflt; 1707 1708 if (!net_eq(net, &init_net)) { 1709 all = kmemdup(all, sizeof(ipv4_devconf), GFP_KERNEL); 1710 if (all == NULL) 1711 goto err_alloc_all; 1712 1713 dflt = kmemdup(dflt, sizeof(ipv4_devconf_dflt), GFP_KERNEL); 1714 if (dflt == NULL) 1715 goto err_alloc_dflt; 1716 1717#ifdef CONFIG_SYSCTL 1718 tbl = kmemdup(tbl, sizeof(ctl_forward_entry), GFP_KERNEL); 1719 if (tbl == NULL) 1720 goto err_alloc_ctl; 1721 1722 tbl[0].data = &all->data[IPV4_DEVCONF_FORWARDING - 1]; 1723 tbl[0].extra1 = all; 1724 tbl[0].extra2 = net; 1725#endif 1726 } 1727 1728#ifdef CONFIG_SYSCTL 1729 err = __devinet_sysctl_register(net, "all", all); 1730 if (err < 0) 1731 goto err_reg_all; 1732 1733 err = __devinet_sysctl_register(net, "default", dflt); 1734 if (err < 0) 1735 goto err_reg_dflt; 1736 1737 err = -ENOMEM; 1738 forw_hdr = register_net_sysctl(net, "net/ipv4", tbl); 1739 if (forw_hdr == NULL) 1740 goto err_reg_ctl; 1741 net->ipv4.forw_hdr = forw_hdr; 1742#endif 1743 1744 net->ipv4.devconf_all = all; 1745 net->ipv4.devconf_dflt = dflt; 1746 return 0; 1747 1748#ifdef CONFIG_SYSCTL 1749err_reg_ctl: 1750 __devinet_sysctl_unregister(dflt); 1751err_reg_dflt: 1752 __devinet_sysctl_unregister(all); 1753err_reg_all: 1754 if (tbl != ctl_forward_entry) 1755 kfree(tbl); 1756err_alloc_ctl: 1757#endif 1758 if (dflt != &ipv4_devconf_dflt) 1759 kfree(dflt); 1760err_alloc_dflt: 1761 if (all != &ipv4_devconf) 1762 kfree(all); 1763err_alloc_all: 1764 return err; 1765} 1766 1767static __net_exit void devinet_exit_net(struct net *net) 1768{ 1769#ifdef CONFIG_SYSCTL 1770 struct ctl_table *tbl; 1771 1772 tbl = net->ipv4.forw_hdr->ctl_table_arg; 1773 unregister_net_sysctl_table(net->ipv4.forw_hdr); 1774 __devinet_sysctl_unregister(net->ipv4.devconf_dflt); 1775 __devinet_sysctl_unregister(net->ipv4.devconf_all); 1776 kfree(tbl); 1777#endif 1778 kfree(net->ipv4.devconf_dflt); 1779 kfree(net->ipv4.devconf_all); 1780} 1781 1782static __net_initdata struct pernet_operations devinet_ops = { 1783 .init = devinet_init_net, 1784 .exit = devinet_exit_net, 1785}; 1786 1787static struct rtnl_af_ops inet_af_ops = { 1788 .family = AF_INET, 1789 .fill_link_af = inet_fill_link_af, 1790 .get_link_af_size = inet_get_link_af_size, 1791 .validate_link_af = inet_validate_link_af, 1792 .set_link_af = inet_set_link_af, 1793}; 1794 1795void __init devinet_init(void) 1796{ 1797 int i; 1798 1799 for (i = 0; i < IN4_ADDR_HSIZE; i++) 1800 INIT_HLIST_HEAD(&inet_addr_lst[i]); 1801 1802 register_pernet_subsys(&devinet_ops); 1803 1804 register_gifconf(PF_INET, inet_gifconf); 1805 register_netdevice_notifier(&ip_netdev_notifier); 1806 1807 rtnl_af_register(&inet_af_ops); 1808 1809 rtnl_register(PF_INET, RTM_NEWADDR, inet_rtm_newaddr, NULL, NULL); 1810 rtnl_register(PF_INET, RTM_DELADDR, inet_rtm_deladdr, NULL, NULL); 1811 rtnl_register(PF_INET, RTM_GETADDR, NULL, inet_dump_ifaddr, NULL); 1812} 1813 1814