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 .flowi4_oif = l3mdev_master_ifindex_rcu(dev), 304 .daddr = ip_hdr(skb)->saddr, 305 .flowi4_tos = RT_TOS(ip_hdr(skb)->tos), 306 .flowi4_scope = scope, 307 .flowi4_mark = IN_DEV_SRC_VMARK(in_dev) ? skb->mark : 0, 308 }; 309 if (!fib_lookup(net, &fl4, &res, 0)) 310 return FIB_RES_PREFSRC(net, res); 311 } else { 312 scope = RT_SCOPE_LINK; 313 } 314 315 return inet_select_addr(dev, ip_hdr(skb)->saddr, scope); 316 } 317 318 /* Given (packet source, input interface) and optional (dst, oif, tos): 319 * - (main) check, that source is valid i.e. not broadcast or our local 320 * address. 321 * - figure out what "logical" interface this packet arrived 322 * and calculate "specific destination" address. 323 * - check, that packet arrived from expected physical interface. 324 * called with rcu_read_lock() 325 */ 326 static int __fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst, 327 u8 tos, int oif, struct net_device *dev, 328 int rpf, struct in_device *idev, u32 *itag) 329 { 330 struct net *net = dev_net(dev); 331 struct flow_keys flkeys; 332 int ret, no_addr; 333 struct fib_result res; 334 struct flowi4 fl4; 335 bool dev_match; 336 337 fl4.flowi4_oif = 0; 338 fl4.flowi4_iif = l3mdev_master_ifindex_rcu(dev); 339 if (!fl4.flowi4_iif) 340 fl4.flowi4_iif = oif ? : LOOPBACK_IFINDEX; 341 fl4.daddr = src; 342 fl4.saddr = dst; 343 fl4.flowi4_tos = tos; 344 fl4.flowi4_scope = RT_SCOPE_UNIVERSE; 345 fl4.flowi4_tun_key.tun_id = 0; 346 fl4.flowi4_flags = 0; 347 fl4.flowi4_uid = sock_net_uid(net, NULL); 348 349 no_addr = idev->ifa_list == NULL; 350 351 fl4.flowi4_mark = IN_DEV_SRC_VMARK(idev) ? skb->mark : 0; 352 if (!fib4_rules_early_flow_dissect(net, skb, &fl4, &flkeys)) { 353 fl4.flowi4_proto = 0; 354 fl4.fl4_sport = 0; 355 fl4.fl4_dport = 0; 356 } 357 358 if (fib_lookup(net, &fl4, &res, 0)) 359 goto last_resort; 360 if (res.type != RTN_UNICAST && 361 (res.type != RTN_LOCAL || !IN_DEV_ACCEPT_LOCAL(idev))) 362 goto e_inval; 363 fib_combine_itag(itag, &res); 364 dev_match = false; 365 366 #ifdef CONFIG_IP_ROUTE_MULTIPATH 367 for (ret = 0; ret < res.fi->fib_nhs; ret++) { 368 struct fib_nh *nh = &res.fi->fib_nh[ret]; 369 370 if (nh->nh_dev == dev) { 371 dev_match = true; 372 break; 373 } else if (l3mdev_master_ifindex_rcu(nh->nh_dev) == dev->ifindex) { 374 dev_match = true; 375 break; 376 } 377 } 378 #else 379 if (FIB_RES_DEV(res) == dev) 380 dev_match = true; 381 #endif 382 if (dev_match) { 383 ret = FIB_RES_NH(res).nh_scope >= RT_SCOPE_HOST; 384 return ret; 385 } 386 if (no_addr) 387 goto last_resort; 388 if (rpf == 1) 389 goto e_rpf; 390 fl4.flowi4_oif = dev->ifindex; 391 392 ret = 0; 393 if (fib_lookup(net, &fl4, &res, FIB_LOOKUP_IGNORE_LINKSTATE) == 0) { 394 if (res.type == RTN_UNICAST) 395 ret = FIB_RES_NH(res).nh_scope >= RT_SCOPE_HOST; 396 } 397 return ret; 398 399 last_resort: 400 if (rpf) 401 goto e_rpf; 402 *itag = 0; 403 return 0; 404 405 e_inval: 406 return -EINVAL; 407 e_rpf: 408 return -EXDEV; 409 } 410 411 /* Ignore rp_filter for packets protected by IPsec. */ 412 int fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst, 413 u8 tos, int oif, struct net_device *dev, 414 struct in_device *idev, u32 *itag) 415 { 416 int r = secpath_exists(skb) ? 0 : IN_DEV_RPFILTER(idev); 417 struct net *net = dev_net(dev); 418 419 if (!r && !fib_num_tclassid_users(net) && 420 (dev->ifindex != oif || !IN_DEV_TX_REDIRECTS(idev))) { 421 if (IN_DEV_ACCEPT_LOCAL(idev)) 422 goto ok; 423 /* with custom local routes in place, checking local addresses 424 * only will be too optimistic, with custom rules, checking 425 * local addresses only can be too strict, e.g. due to vrf 426 */ 427 if (net->ipv4.fib_has_custom_local_routes || 428 fib4_has_custom_rules(net)) 429 goto full_check; 430 if (inet_lookup_ifaddr_rcu(net, src)) 431 return -EINVAL; 432 433 ok: 434 *itag = 0; 435 return 0; 436 } 437 438 full_check: 439 return __fib_validate_source(skb, src, dst, tos, oif, dev, r, idev, itag); 440 } 441 442 static inline __be32 sk_extract_addr(struct sockaddr *addr) 443 { 444 return ((struct sockaddr_in *) addr)->sin_addr.s_addr; 445 } 446 447 static int put_rtax(struct nlattr *mx, int len, int type, u32 value) 448 { 449 struct nlattr *nla; 450 451 nla = (struct nlattr *) ((char *) mx + len); 452 nla->nla_type = type; 453 nla->nla_len = nla_attr_size(4); 454 *(u32 *) nla_data(nla) = value; 455 456 return len + nla_total_size(4); 457 } 458 459 static int rtentry_to_fib_config(struct net *net, int cmd, struct rtentry *rt, 460 struct fib_config *cfg) 461 { 462 __be32 addr; 463 int plen; 464 465 memset(cfg, 0, sizeof(*cfg)); 466 cfg->fc_nlinfo.nl_net = net; 467 468 if (rt->rt_dst.sa_family != AF_INET) 469 return -EAFNOSUPPORT; 470 471 /* 472 * Check mask for validity: 473 * a) it must be contiguous. 474 * b) destination must have all host bits clear. 475 * c) if application forgot to set correct family (AF_INET), 476 * reject request unless it is absolutely clear i.e. 477 * both family and mask are zero. 478 */ 479 plen = 32; 480 addr = sk_extract_addr(&rt->rt_dst); 481 if (!(rt->rt_flags & RTF_HOST)) { 482 __be32 mask = sk_extract_addr(&rt->rt_genmask); 483 484 if (rt->rt_genmask.sa_family != AF_INET) { 485 if (mask || rt->rt_genmask.sa_family) 486 return -EAFNOSUPPORT; 487 } 488 489 if (bad_mask(mask, addr)) 490 return -EINVAL; 491 492 plen = inet_mask_len(mask); 493 } 494 495 cfg->fc_dst_len = plen; 496 cfg->fc_dst = addr; 497 498 if (cmd != SIOCDELRT) { 499 cfg->fc_nlflags = NLM_F_CREATE; 500 cfg->fc_protocol = RTPROT_BOOT; 501 } 502 503 if (rt->rt_metric) 504 cfg->fc_priority = rt->rt_metric - 1; 505 506 if (rt->rt_flags & RTF_REJECT) { 507 cfg->fc_scope = RT_SCOPE_HOST; 508 cfg->fc_type = RTN_UNREACHABLE; 509 return 0; 510 } 511 512 cfg->fc_scope = RT_SCOPE_NOWHERE; 513 cfg->fc_type = RTN_UNICAST; 514 515 if (rt->rt_dev) { 516 char *colon; 517 struct net_device *dev; 518 char devname[IFNAMSIZ]; 519 520 if (copy_from_user(devname, rt->rt_dev, IFNAMSIZ-1)) 521 return -EFAULT; 522 523 devname[IFNAMSIZ-1] = 0; 524 colon = strchr(devname, ':'); 525 if (colon) 526 *colon = 0; 527 dev = __dev_get_by_name(net, devname); 528 if (!dev) 529 return -ENODEV; 530 cfg->fc_oif = dev->ifindex; 531 cfg->fc_table = l3mdev_fib_table(dev); 532 if (colon) { 533 struct in_ifaddr *ifa; 534 struct in_device *in_dev = __in_dev_get_rtnl(dev); 535 if (!in_dev) 536 return -ENODEV; 537 *colon = ':'; 538 for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) 539 if (strcmp(ifa->ifa_label, devname) == 0) 540 break; 541 if (!ifa) 542 return -ENODEV; 543 cfg->fc_prefsrc = ifa->ifa_local; 544 } 545 } 546 547 addr = sk_extract_addr(&rt->rt_gateway); 548 if (rt->rt_gateway.sa_family == AF_INET && addr) { 549 unsigned int addr_type; 550 551 cfg->fc_gw = addr; 552 addr_type = inet_addr_type_table(net, addr, cfg->fc_table); 553 if (rt->rt_flags & RTF_GATEWAY && 554 addr_type == RTN_UNICAST) 555 cfg->fc_scope = RT_SCOPE_UNIVERSE; 556 } 557 558 if (cmd == SIOCDELRT) 559 return 0; 560 561 if (rt->rt_flags & RTF_GATEWAY && !cfg->fc_gw) 562 return -EINVAL; 563 564 if (cfg->fc_scope == RT_SCOPE_NOWHERE) 565 cfg->fc_scope = RT_SCOPE_LINK; 566 567 if (rt->rt_flags & (RTF_MTU | RTF_WINDOW | RTF_IRTT)) { 568 struct nlattr *mx; 569 int len = 0; 570 571 mx = kcalloc(3, nla_total_size(4), GFP_KERNEL); 572 if (!mx) 573 return -ENOMEM; 574 575 if (rt->rt_flags & RTF_MTU) 576 len = put_rtax(mx, len, RTAX_ADVMSS, rt->rt_mtu - 40); 577 578 if (rt->rt_flags & RTF_WINDOW) 579 len = put_rtax(mx, len, RTAX_WINDOW, rt->rt_window); 580 581 if (rt->rt_flags & RTF_IRTT) 582 len = put_rtax(mx, len, RTAX_RTT, rt->rt_irtt << 3); 583 584 cfg->fc_mx = mx; 585 cfg->fc_mx_len = len; 586 } 587 588 return 0; 589 } 590 591 /* 592 * Handle IP routing ioctl calls. 593 * These are used to manipulate the routing tables 594 */ 595 int ip_rt_ioctl(struct net *net, unsigned int cmd, struct rtentry *rt) 596 { 597 struct fib_config cfg; 598 int err; 599 600 switch (cmd) { 601 case SIOCADDRT: /* Add a route */ 602 case SIOCDELRT: /* Delete a route */ 603 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 604 return -EPERM; 605 606 rtnl_lock(); 607 err = rtentry_to_fib_config(net, cmd, rt, &cfg); 608 if (err == 0) { 609 struct fib_table *tb; 610 611 if (cmd == SIOCDELRT) { 612 tb = fib_get_table(net, cfg.fc_table); 613 if (tb) 614 err = fib_table_delete(net, tb, &cfg, 615 NULL); 616 else 617 err = -ESRCH; 618 } else { 619 tb = fib_new_table(net, cfg.fc_table); 620 if (tb) 621 err = fib_table_insert(net, tb, 622 &cfg, NULL); 623 else 624 err = -ENOBUFS; 625 } 626 627 /* allocated by rtentry_to_fib_config() */ 628 kfree(cfg.fc_mx); 629 } 630 rtnl_unlock(); 631 return err; 632 } 633 return -EINVAL; 634 } 635 636 const struct nla_policy rtm_ipv4_policy[RTA_MAX + 1] = { 637 [RTA_DST] = { .type = NLA_U32 }, 638 [RTA_SRC] = { .type = NLA_U32 }, 639 [RTA_IIF] = { .type = NLA_U32 }, 640 [RTA_OIF] = { .type = NLA_U32 }, 641 [RTA_GATEWAY] = { .type = NLA_U32 }, 642 [RTA_PRIORITY] = { .type = NLA_U32 }, 643 [RTA_PREFSRC] = { .type = NLA_U32 }, 644 [RTA_METRICS] = { .type = NLA_NESTED }, 645 [RTA_MULTIPATH] = { .len = sizeof(struct rtnexthop) }, 646 [RTA_FLOW] = { .type = NLA_U32 }, 647 [RTA_ENCAP_TYPE] = { .type = NLA_U16 }, 648 [RTA_ENCAP] = { .type = NLA_NESTED }, 649 [RTA_UID] = { .type = NLA_U32 }, 650 [RTA_MARK] = { .type = NLA_U32 }, 651 [RTA_TABLE] = { .type = NLA_U32 }, 652 [RTA_IP_PROTO] = { .type = NLA_U8 }, 653 [RTA_SPORT] = { .type = NLA_U16 }, 654 [RTA_DPORT] = { .type = NLA_U16 }, 655 }; 656 657 static int rtm_to_fib_config(struct net *net, struct sk_buff *skb, 658 struct nlmsghdr *nlh, struct fib_config *cfg, 659 struct netlink_ext_ack *extack) 660 { 661 struct nlattr *attr; 662 int err, remaining; 663 struct rtmsg *rtm; 664 665 err = nlmsg_validate(nlh, sizeof(*rtm), RTA_MAX, rtm_ipv4_policy, 666 extack); 667 if (err < 0) 668 goto errout; 669 670 memset(cfg, 0, sizeof(*cfg)); 671 672 rtm = nlmsg_data(nlh); 673 cfg->fc_dst_len = rtm->rtm_dst_len; 674 cfg->fc_tos = rtm->rtm_tos; 675 cfg->fc_table = rtm->rtm_table; 676 cfg->fc_protocol = rtm->rtm_protocol; 677 cfg->fc_scope = rtm->rtm_scope; 678 cfg->fc_type = rtm->rtm_type; 679 cfg->fc_flags = rtm->rtm_flags; 680 cfg->fc_nlflags = nlh->nlmsg_flags; 681 682 cfg->fc_nlinfo.portid = NETLINK_CB(skb).portid; 683 cfg->fc_nlinfo.nlh = nlh; 684 cfg->fc_nlinfo.nl_net = net; 685 686 if (cfg->fc_type > RTN_MAX) { 687 NL_SET_ERR_MSG(extack, "Invalid route type"); 688 err = -EINVAL; 689 goto errout; 690 } 691 692 nlmsg_for_each_attr(attr, nlh, sizeof(struct rtmsg), remaining) { 693 switch (nla_type(attr)) { 694 case RTA_DST: 695 cfg->fc_dst = nla_get_be32(attr); 696 break; 697 case RTA_OIF: 698 cfg->fc_oif = nla_get_u32(attr); 699 break; 700 case RTA_GATEWAY: 701 cfg->fc_gw = nla_get_be32(attr); 702 break; 703 case RTA_PRIORITY: 704 cfg->fc_priority = nla_get_u32(attr); 705 break; 706 case RTA_PREFSRC: 707 cfg->fc_prefsrc = nla_get_be32(attr); 708 break; 709 case RTA_METRICS: 710 cfg->fc_mx = nla_data(attr); 711 cfg->fc_mx_len = nla_len(attr); 712 break; 713 case RTA_MULTIPATH: 714 err = lwtunnel_valid_encap_type_attr(nla_data(attr), 715 nla_len(attr), 716 extack); 717 if (err < 0) 718 goto errout; 719 cfg->fc_mp = nla_data(attr); 720 cfg->fc_mp_len = nla_len(attr); 721 break; 722 case RTA_FLOW: 723 cfg->fc_flow = nla_get_u32(attr); 724 break; 725 case RTA_TABLE: 726 cfg->fc_table = nla_get_u32(attr); 727 break; 728 case RTA_ENCAP: 729 cfg->fc_encap = attr; 730 break; 731 case RTA_ENCAP_TYPE: 732 cfg->fc_encap_type = nla_get_u16(attr); 733 err = lwtunnel_valid_encap_type(cfg->fc_encap_type, 734 extack); 735 if (err < 0) 736 goto errout; 737 break; 738 } 739 } 740 741 return 0; 742 errout: 743 return err; 744 } 745 746 static int inet_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh, 747 struct netlink_ext_ack *extack) 748 { 749 struct net *net = sock_net(skb->sk); 750 struct fib_config cfg; 751 struct fib_table *tb; 752 int err; 753 754 err = rtm_to_fib_config(net, skb, nlh, &cfg, extack); 755 if (err < 0) 756 goto errout; 757 758 tb = fib_get_table(net, cfg.fc_table); 759 if (!tb) { 760 NL_SET_ERR_MSG(extack, "FIB table does not exist"); 761 err = -ESRCH; 762 goto errout; 763 } 764 765 err = fib_table_delete(net, tb, &cfg, extack); 766 errout: 767 return err; 768 } 769 770 static int inet_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh, 771 struct netlink_ext_ack *extack) 772 { 773 struct net *net = sock_net(skb->sk); 774 struct fib_config cfg; 775 struct fib_table *tb; 776 int err; 777 778 err = rtm_to_fib_config(net, skb, nlh, &cfg, extack); 779 if (err < 0) 780 goto errout; 781 782 tb = fib_new_table(net, cfg.fc_table); 783 if (!tb) { 784 err = -ENOBUFS; 785 goto errout; 786 } 787 788 err = fib_table_insert(net, tb, &cfg, extack); 789 if (!err && cfg.fc_type == RTN_LOCAL) 790 net->ipv4.fib_has_custom_local_routes = true; 791 errout: 792 return err; 793 } 794 795 static int inet_dump_fib(struct sk_buff *skb, struct netlink_callback *cb) 796 { 797 struct net *net = sock_net(skb->sk); 798 unsigned int h, s_h; 799 unsigned int e = 0, s_e; 800 struct fib_table *tb; 801 struct hlist_head *head; 802 int dumped = 0, err; 803 804 if (nlmsg_len(cb->nlh) >= sizeof(struct rtmsg) && 805 ((struct rtmsg *) nlmsg_data(cb->nlh))->rtm_flags & RTM_F_CLONED) 806 return skb->len; 807 808 s_h = cb->args[0]; 809 s_e = cb->args[1]; 810 811 rcu_read_lock(); 812 813 for (h = s_h; h < FIB_TABLE_HASHSZ; h++, s_e = 0) { 814 e = 0; 815 head = &net->ipv4.fib_table_hash[h]; 816 hlist_for_each_entry_rcu(tb, head, tb_hlist) { 817 if (e < s_e) 818 goto next; 819 if (dumped) 820 memset(&cb->args[2], 0, sizeof(cb->args) - 821 2 * sizeof(cb->args[0])); 822 err = fib_table_dump(tb, skb, cb); 823 if (err < 0) { 824 if (likely(skb->len)) 825 goto out; 826 827 goto out_err; 828 } 829 dumped = 1; 830 next: 831 e++; 832 } 833 } 834 out: 835 err = skb->len; 836 out_err: 837 rcu_read_unlock(); 838 839 cb->args[1] = e; 840 cb->args[0] = h; 841 842 return err; 843 } 844 845 /* Prepare and feed intra-kernel routing request. 846 * Really, it should be netlink message, but :-( netlink 847 * can be not configured, so that we feed it directly 848 * to fib engine. It is legal, because all events occur 849 * only when netlink is already locked. 850 */ 851 static void fib_magic(int cmd, int type, __be32 dst, int dst_len, 852 struct in_ifaddr *ifa, u32 rt_priority) 853 { 854 struct net *net = dev_net(ifa->ifa_dev->dev); 855 u32 tb_id = l3mdev_fib_table(ifa->ifa_dev->dev); 856 struct fib_table *tb; 857 struct fib_config cfg = { 858 .fc_protocol = RTPROT_KERNEL, 859 .fc_type = type, 860 .fc_dst = dst, 861 .fc_dst_len = dst_len, 862 .fc_priority = rt_priority, 863 .fc_prefsrc = ifa->ifa_local, 864 .fc_oif = ifa->ifa_dev->dev->ifindex, 865 .fc_nlflags = NLM_F_CREATE | NLM_F_APPEND, 866 .fc_nlinfo = { 867 .nl_net = net, 868 }, 869 }; 870 871 if (!tb_id) 872 tb_id = (type == RTN_UNICAST) ? RT_TABLE_MAIN : RT_TABLE_LOCAL; 873 874 tb = fib_new_table(net, tb_id); 875 if (!tb) 876 return; 877 878 cfg.fc_table = tb->tb_id; 879 880 if (type != RTN_LOCAL) 881 cfg.fc_scope = RT_SCOPE_LINK; 882 else 883 cfg.fc_scope = RT_SCOPE_HOST; 884 885 if (cmd == RTM_NEWROUTE) 886 fib_table_insert(net, tb, &cfg, NULL); 887 else 888 fib_table_delete(net, tb, &cfg, NULL); 889 } 890 891 void fib_add_ifaddr(struct in_ifaddr *ifa) 892 { 893 struct in_device *in_dev = ifa->ifa_dev; 894 struct net_device *dev = in_dev->dev; 895 struct in_ifaddr *prim = ifa; 896 __be32 mask = ifa->ifa_mask; 897 __be32 addr = ifa->ifa_local; 898 __be32 prefix = ifa->ifa_address & mask; 899 900 if (ifa->ifa_flags & IFA_F_SECONDARY) { 901 prim = inet_ifa_byprefix(in_dev, prefix, mask); 902 if (!prim) { 903 pr_warn("%s: bug: prim == NULL\n", __func__); 904 return; 905 } 906 } 907 908 fib_magic(RTM_NEWROUTE, RTN_LOCAL, addr, 32, prim, 0); 909 910 if (!(dev->flags & IFF_UP)) 911 return; 912 913 /* Add broadcast address, if it is explicitly assigned. */ 914 if (ifa->ifa_broadcast && ifa->ifa_broadcast != htonl(0xFFFFFFFF)) 915 fib_magic(RTM_NEWROUTE, RTN_BROADCAST, ifa->ifa_broadcast, 32, 916 prim, 0); 917 918 if (!ipv4_is_zeronet(prefix) && !(ifa->ifa_flags & IFA_F_SECONDARY) && 919 (prefix != addr || ifa->ifa_prefixlen < 32)) { 920 if (!(ifa->ifa_flags & IFA_F_NOPREFIXROUTE)) 921 fib_magic(RTM_NEWROUTE, 922 dev->flags & IFF_LOOPBACK ? RTN_LOCAL : RTN_UNICAST, 923 prefix, ifa->ifa_prefixlen, prim, 924 ifa->ifa_rt_priority); 925 926 /* Add network specific broadcasts, when it takes a sense */ 927 if (ifa->ifa_prefixlen < 31) { 928 fib_magic(RTM_NEWROUTE, RTN_BROADCAST, prefix, 32, 929 prim, 0); 930 fib_magic(RTM_NEWROUTE, RTN_BROADCAST, prefix | ~mask, 931 32, prim, 0); 932 } 933 } 934 } 935 936 void fib_modify_prefix_metric(struct in_ifaddr *ifa, u32 new_metric) 937 { 938 __be32 prefix = ifa->ifa_address & ifa->ifa_mask; 939 struct in_device *in_dev = ifa->ifa_dev; 940 struct net_device *dev = in_dev->dev; 941 942 if (!(dev->flags & IFF_UP) || 943 ifa->ifa_flags & (IFA_F_SECONDARY | IFA_F_NOPREFIXROUTE) || 944 ipv4_is_zeronet(prefix) || 945 prefix == ifa->ifa_local || ifa->ifa_prefixlen == 32) 946 return; 947 948 /* add the new */ 949 fib_magic(RTM_NEWROUTE, 950 dev->flags & IFF_LOOPBACK ? RTN_LOCAL : RTN_UNICAST, 951 prefix, ifa->ifa_prefixlen, ifa, new_metric); 952 953 /* delete the old */ 954 fib_magic(RTM_DELROUTE, 955 dev->flags & IFF_LOOPBACK ? RTN_LOCAL : RTN_UNICAST, 956 prefix, ifa->ifa_prefixlen, ifa, ifa->ifa_rt_priority); 957 } 958 959 /* Delete primary or secondary address. 960 * Optionally, on secondary address promotion consider the addresses 961 * from subnet iprim as deleted, even if they are in device list. 962 * In this case the secondary ifa can be in device list. 963 */ 964 void fib_del_ifaddr(struct in_ifaddr *ifa, struct in_ifaddr *iprim) 965 { 966 struct in_device *in_dev = ifa->ifa_dev; 967 struct net_device *dev = in_dev->dev; 968 struct in_ifaddr *ifa1; 969 struct in_ifaddr *prim = ifa, *prim1 = NULL; 970 __be32 brd = ifa->ifa_address | ~ifa->ifa_mask; 971 __be32 any = ifa->ifa_address & ifa->ifa_mask; 972 #define LOCAL_OK 1 973 #define BRD_OK 2 974 #define BRD0_OK 4 975 #define BRD1_OK 8 976 unsigned int ok = 0; 977 int subnet = 0; /* Primary network */ 978 int gone = 1; /* Address is missing */ 979 int same_prefsrc = 0; /* Another primary with same IP */ 980 981 if (ifa->ifa_flags & IFA_F_SECONDARY) { 982 prim = inet_ifa_byprefix(in_dev, any, ifa->ifa_mask); 983 if (!prim) { 984 /* if the device has been deleted, we don't perform 985 * address promotion 986 */ 987 if (!in_dev->dead) 988 pr_warn("%s: bug: prim == NULL\n", __func__); 989 return; 990 } 991 if (iprim && iprim != prim) { 992 pr_warn("%s: bug: iprim != prim\n", __func__); 993 return; 994 } 995 } else if (!ipv4_is_zeronet(any) && 996 (any != ifa->ifa_local || ifa->ifa_prefixlen < 32)) { 997 if (!(ifa->ifa_flags & IFA_F_NOPREFIXROUTE)) 998 fib_magic(RTM_DELROUTE, 999 dev->flags & IFF_LOOPBACK ? RTN_LOCAL : RTN_UNICAST, 1000 any, ifa->ifa_prefixlen, prim, 0); 1001 subnet = 1; 1002 } 1003 1004 if (in_dev->dead) 1005 goto no_promotions; 1006 1007 /* Deletion is more complicated than add. 1008 * We should take care of not to delete too much :-) 1009 * 1010 * Scan address list to be sure that addresses are really gone. 1011 */ 1012 1013 for (ifa1 = in_dev->ifa_list; ifa1; ifa1 = ifa1->ifa_next) { 1014 if (ifa1 == ifa) { 1015 /* promotion, keep the IP */ 1016 gone = 0; 1017 continue; 1018 } 1019 /* Ignore IFAs from our subnet */ 1020 if (iprim && ifa1->ifa_mask == iprim->ifa_mask && 1021 inet_ifa_match(ifa1->ifa_address, iprim)) 1022 continue; 1023 1024 /* Ignore ifa1 if it uses different primary IP (prefsrc) */ 1025 if (ifa1->ifa_flags & IFA_F_SECONDARY) { 1026 /* Another address from our subnet? */ 1027 if (ifa1->ifa_mask == prim->ifa_mask && 1028 inet_ifa_match(ifa1->ifa_address, prim)) 1029 prim1 = prim; 1030 else { 1031 /* We reached the secondaries, so 1032 * same_prefsrc should be determined. 1033 */ 1034 if (!same_prefsrc) 1035 continue; 1036 /* Search new prim1 if ifa1 is not 1037 * using the current prim1 1038 */ 1039 if (!prim1 || 1040 ifa1->ifa_mask != prim1->ifa_mask || 1041 !inet_ifa_match(ifa1->ifa_address, prim1)) 1042 prim1 = inet_ifa_byprefix(in_dev, 1043 ifa1->ifa_address, 1044 ifa1->ifa_mask); 1045 if (!prim1) 1046 continue; 1047 if (prim1->ifa_local != prim->ifa_local) 1048 continue; 1049 } 1050 } else { 1051 if (prim->ifa_local != ifa1->ifa_local) 1052 continue; 1053 prim1 = ifa1; 1054 if (prim != prim1) 1055 same_prefsrc = 1; 1056 } 1057 if (ifa->ifa_local == ifa1->ifa_local) 1058 ok |= LOCAL_OK; 1059 if (ifa->ifa_broadcast == ifa1->ifa_broadcast) 1060 ok |= BRD_OK; 1061 if (brd == ifa1->ifa_broadcast) 1062 ok |= BRD1_OK; 1063 if (any == ifa1->ifa_broadcast) 1064 ok |= BRD0_OK; 1065 /* primary has network specific broadcasts */ 1066 if (prim1 == ifa1 && ifa1->ifa_prefixlen < 31) { 1067 __be32 brd1 = ifa1->ifa_address | ~ifa1->ifa_mask; 1068 __be32 any1 = ifa1->ifa_address & ifa1->ifa_mask; 1069 1070 if (!ipv4_is_zeronet(any1)) { 1071 if (ifa->ifa_broadcast == brd1 || 1072 ifa->ifa_broadcast == any1) 1073 ok |= BRD_OK; 1074 if (brd == brd1 || brd == any1) 1075 ok |= BRD1_OK; 1076 if (any == brd1 || any == any1) 1077 ok |= BRD0_OK; 1078 } 1079 } 1080 } 1081 1082 no_promotions: 1083 if (!(ok & BRD_OK)) 1084 fib_magic(RTM_DELROUTE, RTN_BROADCAST, ifa->ifa_broadcast, 32, 1085 prim, 0); 1086 if (subnet && ifa->ifa_prefixlen < 31) { 1087 if (!(ok & BRD1_OK)) 1088 fib_magic(RTM_DELROUTE, RTN_BROADCAST, brd, 32, 1089 prim, 0); 1090 if (!(ok & BRD0_OK)) 1091 fib_magic(RTM_DELROUTE, RTN_BROADCAST, any, 32, 1092 prim, 0); 1093 } 1094 if (!(ok & LOCAL_OK)) { 1095 unsigned int addr_type; 1096 1097 fib_magic(RTM_DELROUTE, RTN_LOCAL, ifa->ifa_local, 32, prim, 0); 1098 1099 /* Check, that this local address finally disappeared. */ 1100 addr_type = inet_addr_type_dev_table(dev_net(dev), dev, 1101 ifa->ifa_local); 1102 if (gone && addr_type != RTN_LOCAL) { 1103 /* And the last, but not the least thing. 1104 * We must flush stray FIB entries. 1105 * 1106 * First of all, we scan fib_info list searching 1107 * for stray nexthop entries, then ignite fib_flush. 1108 */ 1109 if (fib_sync_down_addr(dev, ifa->ifa_local)) 1110 fib_flush(dev_net(dev)); 1111 } 1112 } 1113 #undef LOCAL_OK 1114 #undef BRD_OK 1115 #undef BRD0_OK 1116 #undef BRD1_OK 1117 } 1118 1119 static void nl_fib_lookup(struct net *net, struct fib_result_nl *frn) 1120 { 1121 1122 struct fib_result res; 1123 struct flowi4 fl4 = { 1124 .flowi4_mark = frn->fl_mark, 1125 .daddr = frn->fl_addr, 1126 .flowi4_tos = frn->fl_tos, 1127 .flowi4_scope = frn->fl_scope, 1128 }; 1129 struct fib_table *tb; 1130 1131 rcu_read_lock(); 1132 1133 tb = fib_get_table(net, frn->tb_id_in); 1134 1135 frn->err = -ENOENT; 1136 if (tb) { 1137 local_bh_disable(); 1138 1139 frn->tb_id = tb->tb_id; 1140 frn->err = fib_table_lookup(tb, &fl4, &res, FIB_LOOKUP_NOREF); 1141 1142 if (!frn->err) { 1143 frn->prefixlen = res.prefixlen; 1144 frn->nh_sel = res.nh_sel; 1145 frn->type = res.type; 1146 frn->scope = res.scope; 1147 } 1148 local_bh_enable(); 1149 } 1150 1151 rcu_read_unlock(); 1152 } 1153 1154 static void nl_fib_input(struct sk_buff *skb) 1155 { 1156 struct net *net; 1157 struct fib_result_nl *frn; 1158 struct nlmsghdr *nlh; 1159 u32 portid; 1160 1161 net = sock_net(skb->sk); 1162 nlh = nlmsg_hdr(skb); 1163 if (skb->len < nlmsg_total_size(sizeof(*frn)) || 1164 skb->len < nlh->nlmsg_len || 1165 nlmsg_len(nlh) < sizeof(*frn)) 1166 return; 1167 1168 skb = netlink_skb_clone(skb, GFP_KERNEL); 1169 if (!skb) 1170 return; 1171 nlh = nlmsg_hdr(skb); 1172 1173 frn = (struct fib_result_nl *) nlmsg_data(nlh); 1174 nl_fib_lookup(net, frn); 1175 1176 portid = NETLINK_CB(skb).portid; /* netlink portid */ 1177 NETLINK_CB(skb).portid = 0; /* from kernel */ 1178 NETLINK_CB(skb).dst_group = 0; /* unicast */ 1179 netlink_unicast(net->ipv4.fibnl, skb, portid, MSG_DONTWAIT); 1180 } 1181 1182 static int __net_init nl_fib_lookup_init(struct net *net) 1183 { 1184 struct sock *sk; 1185 struct netlink_kernel_cfg cfg = { 1186 .input = nl_fib_input, 1187 }; 1188 1189 sk = netlink_kernel_create(net, NETLINK_FIB_LOOKUP, &cfg); 1190 if (!sk) 1191 return -EAFNOSUPPORT; 1192 net->ipv4.fibnl = sk; 1193 return 0; 1194 } 1195 1196 static void nl_fib_lookup_exit(struct net *net) 1197 { 1198 netlink_kernel_release(net->ipv4.fibnl); 1199 net->ipv4.fibnl = NULL; 1200 } 1201 1202 static void fib_disable_ip(struct net_device *dev, unsigned long event, 1203 bool force) 1204 { 1205 if (fib_sync_down_dev(dev, event, force)) 1206 fib_flush(dev_net(dev)); 1207 else 1208 rt_cache_flush(dev_net(dev)); 1209 arp_ifdown(dev); 1210 } 1211 1212 static int fib_inetaddr_event(struct notifier_block *this, unsigned long event, void *ptr) 1213 { 1214 struct in_ifaddr *ifa = (struct in_ifaddr *)ptr; 1215 struct net_device *dev = ifa->ifa_dev->dev; 1216 struct net *net = dev_net(dev); 1217 1218 switch (event) { 1219 case NETDEV_UP: 1220 fib_add_ifaddr(ifa); 1221 #ifdef CONFIG_IP_ROUTE_MULTIPATH 1222 fib_sync_up(dev, RTNH_F_DEAD); 1223 #endif 1224 atomic_inc(&net->ipv4.dev_addr_genid); 1225 rt_cache_flush(dev_net(dev)); 1226 break; 1227 case NETDEV_DOWN: 1228 fib_del_ifaddr(ifa, NULL); 1229 atomic_inc(&net->ipv4.dev_addr_genid); 1230 if (!ifa->ifa_dev->ifa_list) { 1231 /* Last address was deleted from this interface. 1232 * Disable IP. 1233 */ 1234 fib_disable_ip(dev, event, true); 1235 } else { 1236 rt_cache_flush(dev_net(dev)); 1237 } 1238 break; 1239 } 1240 return NOTIFY_DONE; 1241 } 1242 1243 static int fib_netdev_event(struct notifier_block *this, unsigned long event, void *ptr) 1244 { 1245 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 1246 struct netdev_notifier_changeupper_info *info; 1247 struct in_device *in_dev; 1248 struct net *net = dev_net(dev); 1249 unsigned int flags; 1250 1251 if (event == NETDEV_UNREGISTER) { 1252 fib_disable_ip(dev, event, true); 1253 rt_flush_dev(dev); 1254 return NOTIFY_DONE; 1255 } 1256 1257 in_dev = __in_dev_get_rtnl(dev); 1258 if (!in_dev) 1259 return NOTIFY_DONE; 1260 1261 switch (event) { 1262 case NETDEV_UP: 1263 for_ifa(in_dev) { 1264 fib_add_ifaddr(ifa); 1265 } endfor_ifa(in_dev); 1266 #ifdef CONFIG_IP_ROUTE_MULTIPATH 1267 fib_sync_up(dev, RTNH_F_DEAD); 1268 #endif 1269 atomic_inc(&net->ipv4.dev_addr_genid); 1270 rt_cache_flush(net); 1271 break; 1272 case NETDEV_DOWN: 1273 fib_disable_ip(dev, event, false); 1274 break; 1275 case NETDEV_CHANGE: 1276 flags = dev_get_flags(dev); 1277 if (flags & (IFF_RUNNING | IFF_LOWER_UP)) 1278 fib_sync_up(dev, RTNH_F_LINKDOWN); 1279 else 1280 fib_sync_down_dev(dev, event, false); 1281 /* fall through */ 1282 case NETDEV_CHANGEMTU: 1283 rt_cache_flush(net); 1284 break; 1285 case NETDEV_CHANGEUPPER: 1286 info = ptr; 1287 /* flush all routes if dev is linked to or unlinked from 1288 * an L3 master device (e.g., VRF) 1289 */ 1290 if (info->upper_dev && netif_is_l3_master(info->upper_dev)) 1291 fib_disable_ip(dev, NETDEV_DOWN, true); 1292 break; 1293 } 1294 return NOTIFY_DONE; 1295 } 1296 1297 static struct notifier_block fib_inetaddr_notifier = { 1298 .notifier_call = fib_inetaddr_event, 1299 }; 1300 1301 static struct notifier_block fib_netdev_notifier = { 1302 .notifier_call = fib_netdev_event, 1303 }; 1304 1305 static int __net_init ip_fib_net_init(struct net *net) 1306 { 1307 int err; 1308 size_t size = sizeof(struct hlist_head) * FIB_TABLE_HASHSZ; 1309 1310 err = fib4_notifier_init(net); 1311 if (err) 1312 return err; 1313 1314 /* Avoid false sharing : Use at least a full cache line */ 1315 size = max_t(size_t, size, L1_CACHE_BYTES); 1316 1317 net->ipv4.fib_table_hash = kzalloc(size, GFP_KERNEL); 1318 if (!net->ipv4.fib_table_hash) { 1319 err = -ENOMEM; 1320 goto err_table_hash_alloc; 1321 } 1322 1323 err = fib4_rules_init(net); 1324 if (err < 0) 1325 goto err_rules_init; 1326 return 0; 1327 1328 err_rules_init: 1329 kfree(net->ipv4.fib_table_hash); 1330 err_table_hash_alloc: 1331 fib4_notifier_exit(net); 1332 return err; 1333 } 1334 1335 static void ip_fib_net_exit(struct net *net) 1336 { 1337 int i; 1338 1339 rtnl_lock(); 1340 #ifdef CONFIG_IP_MULTIPLE_TABLES 1341 RCU_INIT_POINTER(net->ipv4.fib_main, NULL); 1342 RCU_INIT_POINTER(net->ipv4.fib_default, NULL); 1343 #endif 1344 /* Destroy the tables in reverse order to guarantee that the 1345 * local table, ID 255, is destroyed before the main table, ID 1346 * 254. This is necessary as the local table may contain 1347 * references to data contained in the main table. 1348 */ 1349 for (i = FIB_TABLE_HASHSZ - 1; i >= 0; i--) { 1350 struct hlist_head *head = &net->ipv4.fib_table_hash[i]; 1351 struct hlist_node *tmp; 1352 struct fib_table *tb; 1353 1354 hlist_for_each_entry_safe(tb, tmp, head, tb_hlist) { 1355 hlist_del(&tb->tb_hlist); 1356 fib_table_flush(net, tb); 1357 fib_free_table(tb); 1358 } 1359 } 1360 1361 #ifdef CONFIG_IP_MULTIPLE_TABLES 1362 fib4_rules_exit(net); 1363 #endif 1364 rtnl_unlock(); 1365 kfree(net->ipv4.fib_table_hash); 1366 fib4_notifier_exit(net); 1367 } 1368 1369 static int __net_init fib_net_init(struct net *net) 1370 { 1371 int error; 1372 1373 #ifdef CONFIG_IP_ROUTE_CLASSID 1374 net->ipv4.fib_num_tclassid_users = 0; 1375 #endif 1376 error = ip_fib_net_init(net); 1377 if (error < 0) 1378 goto out; 1379 error = nl_fib_lookup_init(net); 1380 if (error < 0) 1381 goto out_nlfl; 1382 error = fib_proc_init(net); 1383 if (error < 0) 1384 goto out_proc; 1385 out: 1386 return error; 1387 1388 out_proc: 1389 nl_fib_lookup_exit(net); 1390 out_nlfl: 1391 ip_fib_net_exit(net); 1392 goto out; 1393 } 1394 1395 static void __net_exit fib_net_exit(struct net *net) 1396 { 1397 fib_proc_exit(net); 1398 nl_fib_lookup_exit(net); 1399 ip_fib_net_exit(net); 1400 } 1401 1402 static struct pernet_operations fib_net_ops = { 1403 .init = fib_net_init, 1404 .exit = fib_net_exit, 1405 }; 1406 1407 void __init ip_fib_init(void) 1408 { 1409 fib_trie_init(); 1410 1411 register_pernet_subsys(&fib_net_ops); 1412 1413 register_netdevice_notifier(&fib_netdev_notifier); 1414 register_inetaddr_notifier(&fib_inetaddr_notifier); 1415 1416 rtnl_register(PF_INET, RTM_NEWROUTE, inet_rtm_newroute, NULL, 0); 1417 rtnl_register(PF_INET, RTM_DELROUTE, inet_rtm_delroute, NULL, 0); 1418 rtnl_register(PF_INET, RTM_GETROUTE, NULL, inet_dump_fib, 0); 1419 } 1420