1 /* 2 * INET An implementation of the TCP/IP protocol suite for the LINUX 3 * operating system. INET is implemented using the BSD Socket 4 * interface as the means of communication with the user level. 5 * 6 * IPv4 Forwarding Information Base: FIB frontend. 7 * 8 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> 9 * 10 * This program is free software; you can redistribute it and/or 11 * modify it under the terms of the GNU General Public License 12 * as published by the Free Software Foundation; either version 13 * 2 of the License, or (at your option) any later version. 14 */ 15 16 #include <linux/module.h> 17 #include <linux/uaccess.h> 18 #include <linux/bitops.h> 19 #include <linux/capability.h> 20 #include <linux/types.h> 21 #include <linux/kernel.h> 22 #include <linux/mm.h> 23 #include <linux/string.h> 24 #include <linux/socket.h> 25 #include <linux/sockios.h> 26 #include <linux/errno.h> 27 #include <linux/in.h> 28 #include <linux/inet.h> 29 #include <linux/inetdevice.h> 30 #include <linux/netdevice.h> 31 #include <linux/if_addr.h> 32 #include <linux/if_arp.h> 33 #include <linux/skbuff.h> 34 #include <linux/cache.h> 35 #include <linux/init.h> 36 #include <linux/list.h> 37 #include <linux/slab.h> 38 39 #include <net/ip.h> 40 #include <net/protocol.h> 41 #include <net/route.h> 42 #include <net/tcp.h> 43 #include <net/sock.h> 44 #include <net/arp.h> 45 #include <net/ip_fib.h> 46 #include <net/rtnetlink.h> 47 #include <net/xfrm.h> 48 #include <net/l3mdev.h> 49 #include <net/lwtunnel.h> 50 #include <trace/events/fib.h> 51 52 #ifndef CONFIG_IP_MULTIPLE_TABLES 53 54 static int __net_init fib4_rules_init(struct net *net) 55 { 56 struct fib_table *local_table, *main_table; 57 58 main_table = fib_trie_table(RT_TABLE_MAIN, NULL); 59 if (!main_table) 60 return -ENOMEM; 61 62 local_table = fib_trie_table(RT_TABLE_LOCAL, main_table); 63 if (!local_table) 64 goto fail; 65 66 hlist_add_head_rcu(&local_table->tb_hlist, 67 &net->ipv4.fib_table_hash[TABLE_LOCAL_INDEX]); 68 hlist_add_head_rcu(&main_table->tb_hlist, 69 &net->ipv4.fib_table_hash[TABLE_MAIN_INDEX]); 70 return 0; 71 72 fail: 73 fib_free_table(main_table); 74 return -ENOMEM; 75 } 76 77 static bool fib4_has_custom_rules(struct net *net) 78 { 79 return false; 80 } 81 #else 82 83 struct fib_table *fib_new_table(struct net *net, u32 id) 84 { 85 struct fib_table *tb, *alias = NULL; 86 unsigned int h; 87 88 if (id == 0) 89 id = RT_TABLE_MAIN; 90 tb = fib_get_table(net, id); 91 if (tb) 92 return tb; 93 94 if (id == RT_TABLE_LOCAL && !net->ipv4.fib_has_custom_rules) 95 alias = fib_new_table(net, RT_TABLE_MAIN); 96 97 tb = fib_trie_table(id, alias); 98 if (!tb) 99 return NULL; 100 101 switch (id) { 102 case RT_TABLE_MAIN: 103 rcu_assign_pointer(net->ipv4.fib_main, tb); 104 break; 105 case RT_TABLE_DEFAULT: 106 rcu_assign_pointer(net->ipv4.fib_default, tb); 107 break; 108 default: 109 break; 110 } 111 112 h = id & (FIB_TABLE_HASHSZ - 1); 113 hlist_add_head_rcu(&tb->tb_hlist, &net->ipv4.fib_table_hash[h]); 114 return tb; 115 } 116 EXPORT_SYMBOL_GPL(fib_new_table); 117 118 /* caller must hold either rtnl or rcu read lock */ 119 struct fib_table *fib_get_table(struct net *net, u32 id) 120 { 121 struct fib_table *tb; 122 struct hlist_head *head; 123 unsigned int h; 124 125 if (id == 0) 126 id = RT_TABLE_MAIN; 127 h = id & (FIB_TABLE_HASHSZ - 1); 128 129 head = &net->ipv4.fib_table_hash[h]; 130 hlist_for_each_entry_rcu(tb, head, tb_hlist) { 131 if (tb->tb_id == id) 132 return tb; 133 } 134 return NULL; 135 } 136 137 static bool fib4_has_custom_rules(struct net *net) 138 { 139 return net->ipv4.fib_has_custom_rules; 140 } 141 #endif /* CONFIG_IP_MULTIPLE_TABLES */ 142 143 static void fib_replace_table(struct net *net, struct fib_table *old, 144 struct fib_table *new) 145 { 146 #ifdef CONFIG_IP_MULTIPLE_TABLES 147 switch (new->tb_id) { 148 case RT_TABLE_MAIN: 149 rcu_assign_pointer(net->ipv4.fib_main, new); 150 break; 151 case RT_TABLE_DEFAULT: 152 rcu_assign_pointer(net->ipv4.fib_default, new); 153 break; 154 default: 155 break; 156 } 157 158 #endif 159 /* replace the old table in the hlist */ 160 hlist_replace_rcu(&old->tb_hlist, &new->tb_hlist); 161 } 162 163 int fib_unmerge(struct net *net) 164 { 165 struct fib_table *old, *new, *main_table; 166 167 /* attempt to fetch local table if it has been allocated */ 168 old = fib_get_table(net, RT_TABLE_LOCAL); 169 if (!old) 170 return 0; 171 172 new = fib_trie_unmerge(old); 173 if (!new) 174 return -ENOMEM; 175 176 /* table is already unmerged */ 177 if (new == old) 178 return 0; 179 180 /* replace merged table with clean table */ 181 fib_replace_table(net, old, new); 182 fib_free_table(old); 183 184 /* attempt to fetch main table if it has been allocated */ 185 main_table = fib_get_table(net, RT_TABLE_MAIN); 186 if (!main_table) 187 return 0; 188 189 /* flush local entries from main table */ 190 fib_table_flush_external(main_table); 191 192 return 0; 193 } 194 195 static void fib_flush(struct net *net) 196 { 197 int flushed = 0; 198 unsigned int h; 199 200 for (h = 0; h < FIB_TABLE_HASHSZ; h++) { 201 struct hlist_head *head = &net->ipv4.fib_table_hash[h]; 202 struct hlist_node *tmp; 203 struct fib_table *tb; 204 205 hlist_for_each_entry_safe(tb, tmp, head, tb_hlist) 206 flushed += fib_table_flush(net, tb); 207 } 208 209 if (flushed) 210 rt_cache_flush(net); 211 } 212 213 /* 214 * Find address type as if only "dev" was present in the system. If 215 * on_dev is NULL then all interfaces are taken into consideration. 216 */ 217 static inline unsigned int __inet_dev_addr_type(struct net *net, 218 const struct net_device *dev, 219 __be32 addr, u32 tb_id) 220 { 221 struct flowi4 fl4 = { .daddr = addr }; 222 struct fib_result res; 223 unsigned int ret = RTN_BROADCAST; 224 struct fib_table *table; 225 226 if (ipv4_is_zeronet(addr) || ipv4_is_lbcast(addr)) 227 return RTN_BROADCAST; 228 if (ipv4_is_multicast(addr)) 229 return RTN_MULTICAST; 230 231 rcu_read_lock(); 232 233 table = fib_get_table(net, tb_id); 234 if (table) { 235 ret = RTN_UNICAST; 236 if (!fib_table_lookup(table, &fl4, &res, FIB_LOOKUP_NOREF)) { 237 if (!dev || dev == res.fi->fib_dev) 238 ret = res.type; 239 } 240 } 241 242 rcu_read_unlock(); 243 return ret; 244 } 245 246 unsigned int inet_addr_type_table(struct net *net, __be32 addr, u32 tb_id) 247 { 248 return __inet_dev_addr_type(net, NULL, addr, tb_id); 249 } 250 EXPORT_SYMBOL(inet_addr_type_table); 251 252 unsigned int inet_addr_type(struct net *net, __be32 addr) 253 { 254 return __inet_dev_addr_type(net, NULL, addr, RT_TABLE_LOCAL); 255 } 256 EXPORT_SYMBOL(inet_addr_type); 257 258 unsigned int inet_dev_addr_type(struct net *net, const struct net_device *dev, 259 __be32 addr) 260 { 261 u32 rt_table = l3mdev_fib_table(dev) ? : RT_TABLE_LOCAL; 262 263 return __inet_dev_addr_type(net, dev, addr, rt_table); 264 } 265 EXPORT_SYMBOL(inet_dev_addr_type); 266 267 /* inet_addr_type with dev == NULL but using the table from a dev 268 * if one is associated 269 */ 270 unsigned int inet_addr_type_dev_table(struct net *net, 271 const struct net_device *dev, 272 __be32 addr) 273 { 274 u32 rt_table = l3mdev_fib_table(dev) ? : RT_TABLE_LOCAL; 275 276 return __inet_dev_addr_type(net, NULL, addr, rt_table); 277 } 278 EXPORT_SYMBOL(inet_addr_type_dev_table); 279 280 __be32 fib_compute_spec_dst(struct sk_buff *skb) 281 { 282 struct net_device *dev = skb->dev; 283 struct in_device *in_dev; 284 struct fib_result res; 285 struct rtable *rt; 286 struct net *net; 287 int scope; 288 289 rt = skb_rtable(skb); 290 if ((rt->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST | RTCF_LOCAL)) == 291 RTCF_LOCAL) 292 return ip_hdr(skb)->daddr; 293 294 in_dev = __in_dev_get_rcu(dev); 295 BUG_ON(!in_dev); 296 297 net = dev_net(dev); 298 299 scope = RT_SCOPE_UNIVERSE; 300 if (!ipv4_is_zeronet(ip_hdr(skb)->saddr)) { 301 struct flowi4 fl4 = { 302 .flowi4_iif = LOOPBACK_IFINDEX, 303 .daddr = ip_hdr(skb)->saddr, 304 .flowi4_tos = RT_TOS(ip_hdr(skb)->tos), 305 .flowi4_scope = scope, 306 .flowi4_mark = IN_DEV_SRC_VMARK(in_dev) ? skb->mark : 0, 307 }; 308 if (!fib_lookup(net, &fl4, &res, 0)) 309 return FIB_RES_PREFSRC(net, res); 310 } else { 311 scope = RT_SCOPE_LINK; 312 } 313 314 return inet_select_addr(dev, ip_hdr(skb)->saddr, scope); 315 } 316 317 /* Given (packet source, input interface) and optional (dst, oif, tos): 318 * - (main) check, that source is valid i.e. not broadcast or our local 319 * address. 320 * - figure out what "logical" interface this packet arrived 321 * and calculate "specific destination" address. 322 * - check, that packet arrived from expected physical interface. 323 * called with rcu_read_lock() 324 */ 325 static int __fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst, 326 u8 tos, int oif, struct net_device *dev, 327 int rpf, struct in_device *idev, u32 *itag) 328 { 329 struct net *net = dev_net(dev); 330 struct flow_keys flkeys; 331 int ret, no_addr; 332 struct fib_result res; 333 struct flowi4 fl4; 334 bool dev_match; 335 336 fl4.flowi4_oif = 0; 337 fl4.flowi4_iif = l3mdev_master_ifindex_rcu(dev); 338 if (!fl4.flowi4_iif) 339 fl4.flowi4_iif = oif ? : LOOPBACK_IFINDEX; 340 fl4.daddr = src; 341 fl4.saddr = dst; 342 fl4.flowi4_tos = tos; 343 fl4.flowi4_scope = RT_SCOPE_UNIVERSE; 344 fl4.flowi4_tun_key.tun_id = 0; 345 fl4.flowi4_flags = 0; 346 fl4.flowi4_uid = sock_net_uid(net, NULL); 347 348 no_addr = idev->ifa_list == NULL; 349 350 fl4.flowi4_mark = IN_DEV_SRC_VMARK(idev) ? skb->mark : 0; 351 if (!fib4_rules_early_flow_dissect(net, skb, &fl4, &flkeys)) { 352 fl4.flowi4_proto = 0; 353 fl4.fl4_sport = 0; 354 fl4.fl4_dport = 0; 355 } 356 357 if (fib_lookup(net, &fl4, &res, 0)) 358 goto last_resort; 359 if (res.type != RTN_UNICAST && 360 (res.type != RTN_LOCAL || !IN_DEV_ACCEPT_LOCAL(idev))) 361 goto e_inval; 362 fib_combine_itag(itag, &res); 363 dev_match = false; 364 365 #ifdef CONFIG_IP_ROUTE_MULTIPATH 366 for (ret = 0; ret < res.fi->fib_nhs; ret++) { 367 struct fib_nh *nh = &res.fi->fib_nh[ret]; 368 369 if (nh->nh_dev == dev) { 370 dev_match = true; 371 break; 372 } else if (l3mdev_master_ifindex_rcu(nh->nh_dev) == dev->ifindex) { 373 dev_match = true; 374 break; 375 } 376 } 377 #else 378 if (FIB_RES_DEV(res) == dev) 379 dev_match = true; 380 #endif 381 if (dev_match) { 382 ret = FIB_RES_NH(res).nh_scope >= RT_SCOPE_HOST; 383 return ret; 384 } 385 if (no_addr) 386 goto last_resort; 387 if (rpf == 1) 388 goto e_rpf; 389 fl4.flowi4_oif = dev->ifindex; 390 391 ret = 0; 392 if (fib_lookup(net, &fl4, &res, FIB_LOOKUP_IGNORE_LINKSTATE) == 0) { 393 if (res.type == RTN_UNICAST) 394 ret = FIB_RES_NH(res).nh_scope >= RT_SCOPE_HOST; 395 } 396 return ret; 397 398 last_resort: 399 if (rpf) 400 goto e_rpf; 401 *itag = 0; 402 return 0; 403 404 e_inval: 405 return -EINVAL; 406 e_rpf: 407 return -EXDEV; 408 } 409 410 /* Ignore rp_filter for packets protected by IPsec. */ 411 int fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst, 412 u8 tos, int oif, struct net_device *dev, 413 struct in_device *idev, u32 *itag) 414 { 415 int r = secpath_exists(skb) ? 0 : IN_DEV_RPFILTER(idev); 416 struct net *net = dev_net(dev); 417 418 if (!r && !fib_num_tclassid_users(net) && 419 (dev->ifindex != oif || !IN_DEV_TX_REDIRECTS(idev))) { 420 if (IN_DEV_ACCEPT_LOCAL(idev)) 421 goto ok; 422 /* with custom local routes in place, checking local addresses 423 * only will be too optimistic, with custom rules, checking 424 * local addresses only can be too strict, e.g. due to vrf 425 */ 426 if (net->ipv4.fib_has_custom_local_routes || 427 fib4_has_custom_rules(net)) 428 goto full_check; 429 if (inet_lookup_ifaddr_rcu(net, src)) 430 return -EINVAL; 431 432 ok: 433 *itag = 0; 434 return 0; 435 } 436 437 full_check: 438 return __fib_validate_source(skb, src, dst, tos, oif, dev, r, idev, itag); 439 } 440 441 static inline __be32 sk_extract_addr(struct sockaddr *addr) 442 { 443 return ((struct sockaddr_in *) addr)->sin_addr.s_addr; 444 } 445 446 static int put_rtax(struct nlattr *mx, int len, int type, u32 value) 447 { 448 struct nlattr *nla; 449 450 nla = (struct nlattr *) ((char *) mx + len); 451 nla->nla_type = type; 452 nla->nla_len = nla_attr_size(4); 453 *(u32 *) nla_data(nla) = value; 454 455 return len + nla_total_size(4); 456 } 457 458 static int rtentry_to_fib_config(struct net *net, int cmd, struct rtentry *rt, 459 struct fib_config *cfg) 460 { 461 __be32 addr; 462 int plen; 463 464 memset(cfg, 0, sizeof(*cfg)); 465 cfg->fc_nlinfo.nl_net = net; 466 467 if (rt->rt_dst.sa_family != AF_INET) 468 return -EAFNOSUPPORT; 469 470 /* 471 * Check mask for validity: 472 * a) it must be contiguous. 473 * b) destination must have all host bits clear. 474 * c) if application forgot to set correct family (AF_INET), 475 * reject request unless it is absolutely clear i.e. 476 * both family and mask are zero. 477 */ 478 plen = 32; 479 addr = sk_extract_addr(&rt->rt_dst); 480 if (!(rt->rt_flags & RTF_HOST)) { 481 __be32 mask = sk_extract_addr(&rt->rt_genmask); 482 483 if (rt->rt_genmask.sa_family != AF_INET) { 484 if (mask || rt->rt_genmask.sa_family) 485 return -EAFNOSUPPORT; 486 } 487 488 if (bad_mask(mask, addr)) 489 return -EINVAL; 490 491 plen = inet_mask_len(mask); 492 } 493 494 cfg->fc_dst_len = plen; 495 cfg->fc_dst = addr; 496 497 if (cmd != SIOCDELRT) { 498 cfg->fc_nlflags = NLM_F_CREATE; 499 cfg->fc_protocol = RTPROT_BOOT; 500 } 501 502 if (rt->rt_metric) 503 cfg->fc_priority = rt->rt_metric - 1; 504 505 if (rt->rt_flags & RTF_REJECT) { 506 cfg->fc_scope = RT_SCOPE_HOST; 507 cfg->fc_type = RTN_UNREACHABLE; 508 return 0; 509 } 510 511 cfg->fc_scope = RT_SCOPE_NOWHERE; 512 cfg->fc_type = RTN_UNICAST; 513 514 if (rt->rt_dev) { 515 char *colon; 516 struct net_device *dev; 517 char devname[IFNAMSIZ]; 518 519 if (copy_from_user(devname, rt->rt_dev, IFNAMSIZ-1)) 520 return -EFAULT; 521 522 devname[IFNAMSIZ-1] = 0; 523 colon = strchr(devname, ':'); 524 if (colon) 525 *colon = 0; 526 dev = __dev_get_by_name(net, devname); 527 if (!dev) 528 return -ENODEV; 529 cfg->fc_oif = dev->ifindex; 530 cfg->fc_table = l3mdev_fib_table(dev); 531 if (colon) { 532 struct in_ifaddr *ifa; 533 struct in_device *in_dev = __in_dev_get_rtnl(dev); 534 if (!in_dev) 535 return -ENODEV; 536 *colon = ':'; 537 for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) 538 if (strcmp(ifa->ifa_label, devname) == 0) 539 break; 540 if (!ifa) 541 return -ENODEV; 542 cfg->fc_prefsrc = ifa->ifa_local; 543 } 544 } 545 546 addr = sk_extract_addr(&rt->rt_gateway); 547 if (rt->rt_gateway.sa_family == AF_INET && addr) { 548 unsigned int addr_type; 549 550 cfg->fc_gw = addr; 551 addr_type = inet_addr_type_table(net, addr, cfg->fc_table); 552 if (rt->rt_flags & RTF_GATEWAY && 553 addr_type == RTN_UNICAST) 554 cfg->fc_scope = RT_SCOPE_UNIVERSE; 555 } 556 557 if (cmd == SIOCDELRT) 558 return 0; 559 560 if (rt->rt_flags & RTF_GATEWAY && !cfg->fc_gw) 561 return -EINVAL; 562 563 if (cfg->fc_scope == RT_SCOPE_NOWHERE) 564 cfg->fc_scope = RT_SCOPE_LINK; 565 566 if (rt->rt_flags & (RTF_MTU | RTF_WINDOW | RTF_IRTT)) { 567 struct nlattr *mx; 568 int len = 0; 569 570 mx = kcalloc(3, nla_total_size(4), GFP_KERNEL); 571 if (!mx) 572 return -ENOMEM; 573 574 if (rt->rt_flags & RTF_MTU) 575 len = put_rtax(mx, len, RTAX_ADVMSS, rt->rt_mtu - 40); 576 577 if (rt->rt_flags & RTF_WINDOW) 578 len = put_rtax(mx, len, RTAX_WINDOW, rt->rt_window); 579 580 if (rt->rt_flags & RTF_IRTT) 581 len = put_rtax(mx, len, RTAX_RTT, rt->rt_irtt << 3); 582 583 cfg->fc_mx = mx; 584 cfg->fc_mx_len = len; 585 } 586 587 return 0; 588 } 589 590 /* 591 * Handle IP routing ioctl calls. 592 * These are used to manipulate the routing tables 593 */ 594 int ip_rt_ioctl(struct net *net, unsigned int cmd, struct rtentry *rt) 595 { 596 struct fib_config cfg; 597 int err; 598 599 switch (cmd) { 600 case SIOCADDRT: /* Add a route */ 601 case SIOCDELRT: /* Delete a route */ 602 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 603 return -EPERM; 604 605 rtnl_lock(); 606 err = rtentry_to_fib_config(net, cmd, rt, &cfg); 607 if (err == 0) { 608 struct fib_table *tb; 609 610 if (cmd == SIOCDELRT) { 611 tb = fib_get_table(net, cfg.fc_table); 612 if (tb) 613 err = fib_table_delete(net, tb, &cfg, 614 NULL); 615 else 616 err = -ESRCH; 617 } else { 618 tb = fib_new_table(net, cfg.fc_table); 619 if (tb) 620 err = fib_table_insert(net, tb, 621 &cfg, NULL); 622 else 623 err = -ENOBUFS; 624 } 625 626 /* allocated by rtentry_to_fib_config() */ 627 kfree(cfg.fc_mx); 628 } 629 rtnl_unlock(); 630 return err; 631 } 632 return -EINVAL; 633 } 634 635 const struct nla_policy rtm_ipv4_policy[RTA_MAX + 1] = { 636 [RTA_DST] = { .type = NLA_U32 }, 637 [RTA_SRC] = { .type = NLA_U32 }, 638 [RTA_IIF] = { .type = NLA_U32 }, 639 [RTA_OIF] = { .type = NLA_U32 }, 640 [RTA_GATEWAY] = { .type = NLA_U32 }, 641 [RTA_PRIORITY] = { .type = NLA_U32 }, 642 [RTA_PREFSRC] = { .type = NLA_U32 }, 643 [RTA_METRICS] = { .type = NLA_NESTED }, 644 [RTA_MULTIPATH] = { .len = sizeof(struct rtnexthop) }, 645 [RTA_FLOW] = { .type = NLA_U32 }, 646 [RTA_ENCAP_TYPE] = { .type = NLA_U16 }, 647 [RTA_ENCAP] = { .type = NLA_NESTED }, 648 [RTA_UID] = { .type = NLA_U32 }, 649 [RTA_MARK] = { .type = NLA_U32 }, 650 [RTA_TABLE] = { .type = NLA_U32 }, 651 [RTA_IP_PROTO] = { .type = NLA_U8 }, 652 [RTA_SPORT] = { .type = NLA_U16 }, 653 [RTA_DPORT] = { .type = NLA_U16 }, 654 }; 655 656 static int rtm_to_fib_config(struct net *net, struct sk_buff *skb, 657 struct nlmsghdr *nlh, struct fib_config *cfg, 658 struct netlink_ext_ack *extack) 659 { 660 struct nlattr *attr; 661 int err, remaining; 662 struct rtmsg *rtm; 663 664 err = nlmsg_validate(nlh, sizeof(*rtm), RTA_MAX, rtm_ipv4_policy, 665 extack); 666 if (err < 0) 667 goto errout; 668 669 memset(cfg, 0, sizeof(*cfg)); 670 671 rtm = nlmsg_data(nlh); 672 cfg->fc_dst_len = rtm->rtm_dst_len; 673 cfg->fc_tos = rtm->rtm_tos; 674 cfg->fc_table = rtm->rtm_table; 675 cfg->fc_protocol = rtm->rtm_protocol; 676 cfg->fc_scope = rtm->rtm_scope; 677 cfg->fc_type = rtm->rtm_type; 678 cfg->fc_flags = rtm->rtm_flags; 679 cfg->fc_nlflags = nlh->nlmsg_flags; 680 681 cfg->fc_nlinfo.portid = NETLINK_CB(skb).portid; 682 cfg->fc_nlinfo.nlh = nlh; 683 cfg->fc_nlinfo.nl_net = net; 684 685 if (cfg->fc_type > RTN_MAX) { 686 NL_SET_ERR_MSG(extack, "Invalid route type"); 687 err = -EINVAL; 688 goto errout; 689 } 690 691 nlmsg_for_each_attr(attr, nlh, sizeof(struct rtmsg), remaining) { 692 switch (nla_type(attr)) { 693 case RTA_DST: 694 cfg->fc_dst = nla_get_be32(attr); 695 break; 696 case RTA_OIF: 697 cfg->fc_oif = nla_get_u32(attr); 698 break; 699 case RTA_GATEWAY: 700 cfg->fc_gw = nla_get_be32(attr); 701 break; 702 case RTA_PRIORITY: 703 cfg->fc_priority = nla_get_u32(attr); 704 break; 705 case RTA_PREFSRC: 706 cfg->fc_prefsrc = nla_get_be32(attr); 707 break; 708 case RTA_METRICS: 709 cfg->fc_mx = nla_data(attr); 710 cfg->fc_mx_len = nla_len(attr); 711 break; 712 case RTA_MULTIPATH: 713 err = lwtunnel_valid_encap_type_attr(nla_data(attr), 714 nla_len(attr), 715 extack); 716 if (err < 0) 717 goto errout; 718 cfg->fc_mp = nla_data(attr); 719 cfg->fc_mp_len = nla_len(attr); 720 break; 721 case RTA_FLOW: 722 cfg->fc_flow = nla_get_u32(attr); 723 break; 724 case RTA_TABLE: 725 cfg->fc_table = nla_get_u32(attr); 726 break; 727 case RTA_ENCAP: 728 cfg->fc_encap = attr; 729 break; 730 case RTA_ENCAP_TYPE: 731 cfg->fc_encap_type = nla_get_u16(attr); 732 err = lwtunnel_valid_encap_type(cfg->fc_encap_type, 733 extack); 734 if (err < 0) 735 goto errout; 736 break; 737 } 738 } 739 740 return 0; 741 errout: 742 return err; 743 } 744 745 static int inet_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh, 746 struct netlink_ext_ack *extack) 747 { 748 struct net *net = sock_net(skb->sk); 749 struct fib_config cfg; 750 struct fib_table *tb; 751 int err; 752 753 err = rtm_to_fib_config(net, skb, nlh, &cfg, extack); 754 if (err < 0) 755 goto errout; 756 757 tb = fib_get_table(net, cfg.fc_table); 758 if (!tb) { 759 NL_SET_ERR_MSG(extack, "FIB table does not exist"); 760 err = -ESRCH; 761 goto errout; 762 } 763 764 err = fib_table_delete(net, tb, &cfg, extack); 765 errout: 766 return err; 767 } 768 769 static int inet_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh, 770 struct netlink_ext_ack *extack) 771 { 772 struct net *net = sock_net(skb->sk); 773 struct fib_config cfg; 774 struct fib_table *tb; 775 int err; 776 777 err = rtm_to_fib_config(net, skb, nlh, &cfg, extack); 778 if (err < 0) 779 goto errout; 780 781 tb = fib_new_table(net, cfg.fc_table); 782 if (!tb) { 783 err = -ENOBUFS; 784 goto errout; 785 } 786 787 err = fib_table_insert(net, tb, &cfg, extack); 788 if (!err && cfg.fc_type == RTN_LOCAL) 789 net->ipv4.fib_has_custom_local_routes = true; 790 errout: 791 return err; 792 } 793 794 static int inet_dump_fib(struct sk_buff *skb, struct netlink_callback *cb) 795 { 796 struct net *net = sock_net(skb->sk); 797 unsigned int h, s_h; 798 unsigned int e = 0, s_e; 799 struct fib_table *tb; 800 struct hlist_head *head; 801 int dumped = 0, err; 802 803 if (nlmsg_len(cb->nlh) >= sizeof(struct rtmsg) && 804 ((struct rtmsg *) nlmsg_data(cb->nlh))->rtm_flags & RTM_F_CLONED) 805 return skb->len; 806 807 s_h = cb->args[0]; 808 s_e = cb->args[1]; 809 810 rcu_read_lock(); 811 812 for (h = s_h; h < FIB_TABLE_HASHSZ; h++, s_e = 0) { 813 e = 0; 814 head = &net->ipv4.fib_table_hash[h]; 815 hlist_for_each_entry_rcu(tb, head, tb_hlist) { 816 if (e < s_e) 817 goto next; 818 if (dumped) 819 memset(&cb->args[2], 0, sizeof(cb->args) - 820 2 * sizeof(cb->args[0])); 821 err = fib_table_dump(tb, skb, cb); 822 if (err < 0) { 823 if (likely(skb->len)) 824 goto out; 825 826 goto out_err; 827 } 828 dumped = 1; 829 next: 830 e++; 831 } 832 } 833 out: 834 err = skb->len; 835 out_err: 836 rcu_read_unlock(); 837 838 cb->args[1] = e; 839 cb->args[0] = h; 840 841 return err; 842 } 843 844 /* Prepare and feed intra-kernel routing request. 845 * Really, it should be netlink message, but :-( netlink 846 * can be not configured, so that we feed it directly 847 * to fib engine. It is legal, because all events occur 848 * only when netlink is already locked. 849 */ 850 static void fib_magic(int cmd, int type, __be32 dst, int dst_len, 851 struct in_ifaddr *ifa, u32 rt_priority) 852 { 853 struct net *net = dev_net(ifa->ifa_dev->dev); 854 u32 tb_id = l3mdev_fib_table(ifa->ifa_dev->dev); 855 struct fib_table *tb; 856 struct fib_config cfg = { 857 .fc_protocol = RTPROT_KERNEL, 858 .fc_type = type, 859 .fc_dst = dst, 860 .fc_dst_len = dst_len, 861 .fc_priority = rt_priority, 862 .fc_prefsrc = ifa->ifa_local, 863 .fc_oif = ifa->ifa_dev->dev->ifindex, 864 .fc_nlflags = NLM_F_CREATE | NLM_F_APPEND, 865 .fc_nlinfo = { 866 .nl_net = net, 867 }, 868 }; 869 870 if (!tb_id) 871 tb_id = (type == RTN_UNICAST) ? RT_TABLE_MAIN : RT_TABLE_LOCAL; 872 873 tb = fib_new_table(net, tb_id); 874 if (!tb) 875 return; 876 877 cfg.fc_table = tb->tb_id; 878 879 if (type != RTN_LOCAL) 880 cfg.fc_scope = RT_SCOPE_LINK; 881 else 882 cfg.fc_scope = RT_SCOPE_HOST; 883 884 if (cmd == RTM_NEWROUTE) 885 fib_table_insert(net, tb, &cfg, NULL); 886 else 887 fib_table_delete(net, tb, &cfg, NULL); 888 } 889 890 void fib_add_ifaddr(struct in_ifaddr *ifa) 891 { 892 struct in_device *in_dev = ifa->ifa_dev; 893 struct net_device *dev = in_dev->dev; 894 struct in_ifaddr *prim = ifa; 895 __be32 mask = ifa->ifa_mask; 896 __be32 addr = ifa->ifa_local; 897 __be32 prefix = ifa->ifa_address & mask; 898 899 if (ifa->ifa_flags & IFA_F_SECONDARY) { 900 prim = inet_ifa_byprefix(in_dev, prefix, mask); 901 if (!prim) { 902 pr_warn("%s: bug: prim == NULL\n", __func__); 903 return; 904 } 905 } 906 907 fib_magic(RTM_NEWROUTE, RTN_LOCAL, addr, 32, prim, 0); 908 909 if (!(dev->flags & IFF_UP)) 910 return; 911 912 /* Add broadcast address, if it is explicitly assigned. */ 913 if (ifa->ifa_broadcast && ifa->ifa_broadcast != htonl(0xFFFFFFFF)) 914 fib_magic(RTM_NEWROUTE, RTN_BROADCAST, ifa->ifa_broadcast, 32, 915 prim, 0); 916 917 if (!ipv4_is_zeronet(prefix) && !(ifa->ifa_flags & IFA_F_SECONDARY) && 918 (prefix != addr || ifa->ifa_prefixlen < 32)) { 919 if (!(ifa->ifa_flags & IFA_F_NOPREFIXROUTE)) 920 fib_magic(RTM_NEWROUTE, 921 dev->flags & IFF_LOOPBACK ? RTN_LOCAL : RTN_UNICAST, 922 prefix, ifa->ifa_prefixlen, prim, 923 ifa->ifa_rt_priority); 924 925 /* Add network specific broadcasts, when it takes a sense */ 926 if (ifa->ifa_prefixlen < 31) { 927 fib_magic(RTM_NEWROUTE, RTN_BROADCAST, prefix, 32, 928 prim, 0); 929 fib_magic(RTM_NEWROUTE, RTN_BROADCAST, prefix | ~mask, 930 32, prim, 0); 931 } 932 } 933 } 934 935 void fib_modify_prefix_metric(struct in_ifaddr *ifa, u32 new_metric) 936 { 937 __be32 prefix = ifa->ifa_address & ifa->ifa_mask; 938 struct in_device *in_dev = ifa->ifa_dev; 939 struct net_device *dev = in_dev->dev; 940 941 if (!(dev->flags & IFF_UP) || 942 ifa->ifa_flags & (IFA_F_SECONDARY | IFA_F_NOPREFIXROUTE) || 943 ipv4_is_zeronet(prefix) || 944 prefix == ifa->ifa_local || ifa->ifa_prefixlen == 32) 945 return; 946 947 /* add the new */ 948 fib_magic(RTM_NEWROUTE, 949 dev->flags & IFF_LOOPBACK ? RTN_LOCAL : RTN_UNICAST, 950 prefix, ifa->ifa_prefixlen, ifa, new_metric); 951 952 /* delete the old */ 953 fib_magic(RTM_DELROUTE, 954 dev->flags & IFF_LOOPBACK ? RTN_LOCAL : RTN_UNICAST, 955 prefix, ifa->ifa_prefixlen, ifa, ifa->ifa_rt_priority); 956 } 957 958 /* Delete primary or secondary address. 959 * Optionally, on secondary address promotion consider the addresses 960 * from subnet iprim as deleted, even if they are in device list. 961 * In this case the secondary ifa can be in device list. 962 */ 963 void fib_del_ifaddr(struct in_ifaddr *ifa, struct in_ifaddr *iprim) 964 { 965 struct in_device *in_dev = ifa->ifa_dev; 966 struct net_device *dev = in_dev->dev; 967 struct in_ifaddr *ifa1; 968 struct in_ifaddr *prim = ifa, *prim1 = NULL; 969 __be32 brd = ifa->ifa_address | ~ifa->ifa_mask; 970 __be32 any = ifa->ifa_address & ifa->ifa_mask; 971 #define LOCAL_OK 1 972 #define BRD_OK 2 973 #define BRD0_OK 4 974 #define BRD1_OK 8 975 unsigned int ok = 0; 976 int subnet = 0; /* Primary network */ 977 int gone = 1; /* Address is missing */ 978 int same_prefsrc = 0; /* Another primary with same IP */ 979 980 if (ifa->ifa_flags & IFA_F_SECONDARY) { 981 prim = inet_ifa_byprefix(in_dev, any, ifa->ifa_mask); 982 if (!prim) { 983 /* if the device has been deleted, we don't perform 984 * address promotion 985 */ 986 if (!in_dev->dead) 987 pr_warn("%s: bug: prim == NULL\n", __func__); 988 return; 989 } 990 if (iprim && iprim != prim) { 991 pr_warn("%s: bug: iprim != prim\n", __func__); 992 return; 993 } 994 } else if (!ipv4_is_zeronet(any) && 995 (any != ifa->ifa_local || ifa->ifa_prefixlen < 32)) { 996 if (!(ifa->ifa_flags & IFA_F_NOPREFIXROUTE)) 997 fib_magic(RTM_DELROUTE, 998 dev->flags & IFF_LOOPBACK ? RTN_LOCAL : RTN_UNICAST, 999 any, ifa->ifa_prefixlen, prim, 0); 1000 subnet = 1; 1001 } 1002 1003 if (in_dev->dead) 1004 goto no_promotions; 1005 1006 /* Deletion is more complicated than add. 1007 * We should take care of not to delete too much :-) 1008 * 1009 * Scan address list to be sure that addresses are really gone. 1010 */ 1011 1012 for (ifa1 = in_dev->ifa_list; ifa1; ifa1 = ifa1->ifa_next) { 1013 if (ifa1 == ifa) { 1014 /* promotion, keep the IP */ 1015 gone = 0; 1016 continue; 1017 } 1018 /* Ignore IFAs from our subnet */ 1019 if (iprim && ifa1->ifa_mask == iprim->ifa_mask && 1020 inet_ifa_match(ifa1->ifa_address, iprim)) 1021 continue; 1022 1023 /* Ignore ifa1 if it uses different primary IP (prefsrc) */ 1024 if (ifa1->ifa_flags & IFA_F_SECONDARY) { 1025 /* Another address from our subnet? */ 1026 if (ifa1->ifa_mask == prim->ifa_mask && 1027 inet_ifa_match(ifa1->ifa_address, prim)) 1028 prim1 = prim; 1029 else { 1030 /* We reached the secondaries, so 1031 * same_prefsrc should be determined. 1032 */ 1033 if (!same_prefsrc) 1034 continue; 1035 /* Search new prim1 if ifa1 is not 1036 * using the current prim1 1037 */ 1038 if (!prim1 || 1039 ifa1->ifa_mask != prim1->ifa_mask || 1040 !inet_ifa_match(ifa1->ifa_address, prim1)) 1041 prim1 = inet_ifa_byprefix(in_dev, 1042 ifa1->ifa_address, 1043 ifa1->ifa_mask); 1044 if (!prim1) 1045 continue; 1046 if (prim1->ifa_local != prim->ifa_local) 1047 continue; 1048 } 1049 } else { 1050 if (prim->ifa_local != ifa1->ifa_local) 1051 continue; 1052 prim1 = ifa1; 1053 if (prim != prim1) 1054 same_prefsrc = 1; 1055 } 1056 if (ifa->ifa_local == ifa1->ifa_local) 1057 ok |= LOCAL_OK; 1058 if (ifa->ifa_broadcast == ifa1->ifa_broadcast) 1059 ok |= BRD_OK; 1060 if (brd == ifa1->ifa_broadcast) 1061 ok |= BRD1_OK; 1062 if (any == ifa1->ifa_broadcast) 1063 ok |= BRD0_OK; 1064 /* primary has network specific broadcasts */ 1065 if (prim1 == ifa1 && ifa1->ifa_prefixlen < 31) { 1066 __be32 brd1 = ifa1->ifa_address | ~ifa1->ifa_mask; 1067 __be32 any1 = ifa1->ifa_address & ifa1->ifa_mask; 1068 1069 if (!ipv4_is_zeronet(any1)) { 1070 if (ifa->ifa_broadcast == brd1 || 1071 ifa->ifa_broadcast == any1) 1072 ok |= BRD_OK; 1073 if (brd == brd1 || brd == any1) 1074 ok |= BRD1_OK; 1075 if (any == brd1 || any == any1) 1076 ok |= BRD0_OK; 1077 } 1078 } 1079 } 1080 1081 no_promotions: 1082 if (!(ok & BRD_OK)) 1083 fib_magic(RTM_DELROUTE, RTN_BROADCAST, ifa->ifa_broadcast, 32, 1084 prim, 0); 1085 if (subnet && ifa->ifa_prefixlen < 31) { 1086 if (!(ok & BRD1_OK)) 1087 fib_magic(RTM_DELROUTE, RTN_BROADCAST, brd, 32, 1088 prim, 0); 1089 if (!(ok & BRD0_OK)) 1090 fib_magic(RTM_DELROUTE, RTN_BROADCAST, any, 32, 1091 prim, 0); 1092 } 1093 if (!(ok & LOCAL_OK)) { 1094 unsigned int addr_type; 1095 1096 fib_magic(RTM_DELROUTE, RTN_LOCAL, ifa->ifa_local, 32, prim, 0); 1097 1098 /* Check, that this local address finally disappeared. */ 1099 addr_type = inet_addr_type_dev_table(dev_net(dev), dev, 1100 ifa->ifa_local); 1101 if (gone && addr_type != RTN_LOCAL) { 1102 /* And the last, but not the least thing. 1103 * We must flush stray FIB entries. 1104 * 1105 * First of all, we scan fib_info list searching 1106 * for stray nexthop entries, then ignite fib_flush. 1107 */ 1108 if (fib_sync_down_addr(dev, ifa->ifa_local)) 1109 fib_flush(dev_net(dev)); 1110 } 1111 } 1112 #undef LOCAL_OK 1113 #undef BRD_OK 1114 #undef BRD0_OK 1115 #undef BRD1_OK 1116 } 1117 1118 static void nl_fib_lookup(struct net *net, struct fib_result_nl *frn) 1119 { 1120 1121 struct fib_result res; 1122 struct flowi4 fl4 = { 1123 .flowi4_mark = frn->fl_mark, 1124 .daddr = frn->fl_addr, 1125 .flowi4_tos = frn->fl_tos, 1126 .flowi4_scope = frn->fl_scope, 1127 }; 1128 struct fib_table *tb; 1129 1130 rcu_read_lock(); 1131 1132 tb = fib_get_table(net, frn->tb_id_in); 1133 1134 frn->err = -ENOENT; 1135 if (tb) { 1136 local_bh_disable(); 1137 1138 frn->tb_id = tb->tb_id; 1139 frn->err = fib_table_lookup(tb, &fl4, &res, FIB_LOOKUP_NOREF); 1140 1141 if (!frn->err) { 1142 frn->prefixlen = res.prefixlen; 1143 frn->nh_sel = res.nh_sel; 1144 frn->type = res.type; 1145 frn->scope = res.scope; 1146 } 1147 local_bh_enable(); 1148 } 1149 1150 rcu_read_unlock(); 1151 } 1152 1153 static void nl_fib_input(struct sk_buff *skb) 1154 { 1155 struct net *net; 1156 struct fib_result_nl *frn; 1157 struct nlmsghdr *nlh; 1158 u32 portid; 1159 1160 net = sock_net(skb->sk); 1161 nlh = nlmsg_hdr(skb); 1162 if (skb->len < nlmsg_total_size(sizeof(*frn)) || 1163 skb->len < nlh->nlmsg_len || 1164 nlmsg_len(nlh) < sizeof(*frn)) 1165 return; 1166 1167 skb = netlink_skb_clone(skb, GFP_KERNEL); 1168 if (!skb) 1169 return; 1170 nlh = nlmsg_hdr(skb); 1171 1172 frn = (struct fib_result_nl *) nlmsg_data(nlh); 1173 nl_fib_lookup(net, frn); 1174 1175 portid = NETLINK_CB(skb).portid; /* netlink portid */ 1176 NETLINK_CB(skb).portid = 0; /* from kernel */ 1177 NETLINK_CB(skb).dst_group = 0; /* unicast */ 1178 netlink_unicast(net->ipv4.fibnl, skb, portid, MSG_DONTWAIT); 1179 } 1180 1181 static int __net_init nl_fib_lookup_init(struct net *net) 1182 { 1183 struct sock *sk; 1184 struct netlink_kernel_cfg cfg = { 1185 .input = nl_fib_input, 1186 }; 1187 1188 sk = netlink_kernel_create(net, NETLINK_FIB_LOOKUP, &cfg); 1189 if (!sk) 1190 return -EAFNOSUPPORT; 1191 net->ipv4.fibnl = sk; 1192 return 0; 1193 } 1194 1195 static void nl_fib_lookup_exit(struct net *net) 1196 { 1197 netlink_kernel_release(net->ipv4.fibnl); 1198 net->ipv4.fibnl = NULL; 1199 } 1200 1201 static void fib_disable_ip(struct net_device *dev, unsigned long event, 1202 bool force) 1203 { 1204 if (fib_sync_down_dev(dev, event, force)) 1205 fib_flush(dev_net(dev)); 1206 else 1207 rt_cache_flush(dev_net(dev)); 1208 arp_ifdown(dev); 1209 } 1210 1211 static int fib_inetaddr_event(struct notifier_block *this, unsigned long event, void *ptr) 1212 { 1213 struct in_ifaddr *ifa = (struct in_ifaddr *)ptr; 1214 struct net_device *dev = ifa->ifa_dev->dev; 1215 struct net *net = dev_net(dev); 1216 1217 switch (event) { 1218 case NETDEV_UP: 1219 fib_add_ifaddr(ifa); 1220 #ifdef CONFIG_IP_ROUTE_MULTIPATH 1221 fib_sync_up(dev, RTNH_F_DEAD); 1222 #endif 1223 atomic_inc(&net->ipv4.dev_addr_genid); 1224 rt_cache_flush(dev_net(dev)); 1225 break; 1226 case NETDEV_DOWN: 1227 fib_del_ifaddr(ifa, NULL); 1228 atomic_inc(&net->ipv4.dev_addr_genid); 1229 if (!ifa->ifa_dev->ifa_list) { 1230 /* Last address was deleted from this interface. 1231 * Disable IP. 1232 */ 1233 fib_disable_ip(dev, event, true); 1234 } else { 1235 rt_cache_flush(dev_net(dev)); 1236 } 1237 break; 1238 } 1239 return NOTIFY_DONE; 1240 } 1241 1242 static int fib_netdev_event(struct notifier_block *this, unsigned long event, void *ptr) 1243 { 1244 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 1245 struct netdev_notifier_changeupper_info *info; 1246 struct in_device *in_dev; 1247 struct net *net = dev_net(dev); 1248 unsigned int flags; 1249 1250 if (event == NETDEV_UNREGISTER) { 1251 fib_disable_ip(dev, event, true); 1252 rt_flush_dev(dev); 1253 return NOTIFY_DONE; 1254 } 1255 1256 in_dev = __in_dev_get_rtnl(dev); 1257 if (!in_dev) 1258 return NOTIFY_DONE; 1259 1260 switch (event) { 1261 case NETDEV_UP: 1262 for_ifa(in_dev) { 1263 fib_add_ifaddr(ifa); 1264 } endfor_ifa(in_dev); 1265 #ifdef CONFIG_IP_ROUTE_MULTIPATH 1266 fib_sync_up(dev, RTNH_F_DEAD); 1267 #endif 1268 atomic_inc(&net->ipv4.dev_addr_genid); 1269 rt_cache_flush(net); 1270 break; 1271 case NETDEV_DOWN: 1272 fib_disable_ip(dev, event, false); 1273 break; 1274 case NETDEV_CHANGE: 1275 flags = dev_get_flags(dev); 1276 if (flags & (IFF_RUNNING | IFF_LOWER_UP)) 1277 fib_sync_up(dev, RTNH_F_LINKDOWN); 1278 else 1279 fib_sync_down_dev(dev, event, false); 1280 /* fall through */ 1281 case NETDEV_CHANGEMTU: 1282 rt_cache_flush(net); 1283 break; 1284 case NETDEV_CHANGEUPPER: 1285 info = ptr; 1286 /* flush all routes if dev is linked to or unlinked from 1287 * an L3 master device (e.g., VRF) 1288 */ 1289 if (info->upper_dev && netif_is_l3_master(info->upper_dev)) 1290 fib_disable_ip(dev, NETDEV_DOWN, true); 1291 break; 1292 } 1293 return NOTIFY_DONE; 1294 } 1295 1296 static struct notifier_block fib_inetaddr_notifier = { 1297 .notifier_call = fib_inetaddr_event, 1298 }; 1299 1300 static struct notifier_block fib_netdev_notifier = { 1301 .notifier_call = fib_netdev_event, 1302 }; 1303 1304 static int __net_init ip_fib_net_init(struct net *net) 1305 { 1306 int err; 1307 size_t size = sizeof(struct hlist_head) * FIB_TABLE_HASHSZ; 1308 1309 err = fib4_notifier_init(net); 1310 if (err) 1311 return err; 1312 1313 /* Avoid false sharing : Use at least a full cache line */ 1314 size = max_t(size_t, size, L1_CACHE_BYTES); 1315 1316 net->ipv4.fib_table_hash = kzalloc(size, GFP_KERNEL); 1317 if (!net->ipv4.fib_table_hash) { 1318 err = -ENOMEM; 1319 goto err_table_hash_alloc; 1320 } 1321 1322 err = fib4_rules_init(net); 1323 if (err < 0) 1324 goto err_rules_init; 1325 return 0; 1326 1327 err_rules_init: 1328 kfree(net->ipv4.fib_table_hash); 1329 err_table_hash_alloc: 1330 fib4_notifier_exit(net); 1331 return err; 1332 } 1333 1334 static void ip_fib_net_exit(struct net *net) 1335 { 1336 int i; 1337 1338 rtnl_lock(); 1339 #ifdef CONFIG_IP_MULTIPLE_TABLES 1340 RCU_INIT_POINTER(net->ipv4.fib_main, NULL); 1341 RCU_INIT_POINTER(net->ipv4.fib_default, NULL); 1342 #endif 1343 /* Destroy the tables in reverse order to guarantee that the 1344 * local table, ID 255, is destroyed before the main table, ID 1345 * 254. This is necessary as the local table may contain 1346 * references to data contained in the main table. 1347 */ 1348 for (i = FIB_TABLE_HASHSZ - 1; i >= 0; i--) { 1349 struct hlist_head *head = &net->ipv4.fib_table_hash[i]; 1350 struct hlist_node *tmp; 1351 struct fib_table *tb; 1352 1353 hlist_for_each_entry_safe(tb, tmp, head, tb_hlist) { 1354 hlist_del(&tb->tb_hlist); 1355 fib_table_flush(net, tb); 1356 fib_free_table(tb); 1357 } 1358 } 1359 1360 #ifdef CONFIG_IP_MULTIPLE_TABLES 1361 fib4_rules_exit(net); 1362 #endif 1363 rtnl_unlock(); 1364 kfree(net->ipv4.fib_table_hash); 1365 fib4_notifier_exit(net); 1366 } 1367 1368 static int __net_init fib_net_init(struct net *net) 1369 { 1370 int error; 1371 1372 #ifdef CONFIG_IP_ROUTE_CLASSID 1373 net->ipv4.fib_num_tclassid_users = 0; 1374 #endif 1375 error = ip_fib_net_init(net); 1376 if (error < 0) 1377 goto out; 1378 error = nl_fib_lookup_init(net); 1379 if (error < 0) 1380 goto out_nlfl; 1381 error = fib_proc_init(net); 1382 if (error < 0) 1383 goto out_proc; 1384 out: 1385 return error; 1386 1387 out_proc: 1388 nl_fib_lookup_exit(net); 1389 out_nlfl: 1390 ip_fib_net_exit(net); 1391 goto out; 1392 } 1393 1394 static void __net_exit fib_net_exit(struct net *net) 1395 { 1396 fib_proc_exit(net); 1397 nl_fib_lookup_exit(net); 1398 ip_fib_net_exit(net); 1399 } 1400 1401 static struct pernet_operations fib_net_ops = { 1402 .init = fib_net_init, 1403 .exit = fib_net_exit, 1404 }; 1405 1406 void __init ip_fib_init(void) 1407 { 1408 fib_trie_init(); 1409 1410 register_pernet_subsys(&fib_net_ops); 1411 1412 register_netdevice_notifier(&fib_netdev_notifier); 1413 register_inetaddr_notifier(&fib_inetaddr_notifier); 1414 1415 rtnl_register(PF_INET, RTM_NEWROUTE, inet_rtm_newroute, NULL, 0); 1416 rtnl_register(PF_INET, RTM_DELROUTE, inet_rtm_delroute, NULL, 0); 1417 rtnl_register(PF_INET, RTM_GETROUTE, NULL, inet_dump_fib, 0); 1418 } 1419