fib_frontend.c revision d9c9df8c9368f4102324e8c3923edae83974602b
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 * Version: $Id: fib_frontend.c,v 1.26 2001/10/31 21:55:54 davem Exp $ 9 * 10 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> 11 * 12 * This program is free software; you can redistribute it and/or 13 * modify it under the terms of the GNU General Public License 14 * as published by the Free Software Foundation; either version 15 * 2 of the License, or (at your option) any later version. 16 */ 17 18#include <linux/module.h> 19#include <asm/uaccess.h> 20#include <asm/system.h> 21#include <linux/bitops.h> 22#include <linux/capability.h> 23#include <linux/types.h> 24#include <linux/kernel.h> 25#include <linux/sched.h> 26#include <linux/mm.h> 27#include <linux/string.h> 28#include <linux/socket.h> 29#include <linux/sockios.h> 30#include <linux/errno.h> 31#include <linux/in.h> 32#include <linux/inet.h> 33#include <linux/inetdevice.h> 34#include <linux/netdevice.h> 35#include <linux/if_addr.h> 36#include <linux/if_arp.h> 37#include <linux/skbuff.h> 38#include <linux/netlink.h> 39#include <linux/init.h> 40#include <linux/list.h> 41 42#include <net/ip.h> 43#include <net/protocol.h> 44#include <net/route.h> 45#include <net/tcp.h> 46#include <net/sock.h> 47#include <net/icmp.h> 48#include <net/arp.h> 49#include <net/ip_fib.h> 50 51#define FFprint(a...) printk(KERN_DEBUG a) 52 53#ifndef CONFIG_IP_MULTIPLE_TABLES 54 55struct fib_table *ip_fib_local_table; 56struct fib_table *ip_fib_main_table; 57 58#define FIB_TABLE_HASHSZ 1 59static struct hlist_head fib_table_hash[FIB_TABLE_HASHSZ]; 60 61#else 62 63#define FIB_TABLE_HASHSZ 256 64static struct hlist_head fib_table_hash[FIB_TABLE_HASHSZ]; 65 66struct fib_table *fib_new_table(u32 id) 67{ 68 struct fib_table *tb; 69 unsigned int h; 70 71 if (id == 0) 72 id = RT_TABLE_MAIN; 73 tb = fib_get_table(id); 74 if (tb) 75 return tb; 76 tb = fib_hash_init(id); 77 if (!tb) 78 return NULL; 79 h = id & (FIB_TABLE_HASHSZ - 1); 80 hlist_add_head_rcu(&tb->tb_hlist, &fib_table_hash[h]); 81 return tb; 82} 83 84struct fib_table *fib_get_table(u32 id) 85{ 86 struct fib_table *tb; 87 struct hlist_node *node; 88 unsigned int h; 89 90 if (id == 0) 91 id = RT_TABLE_MAIN; 92 h = id & (FIB_TABLE_HASHSZ - 1); 93 rcu_read_lock(); 94 hlist_for_each_entry_rcu(tb, node, &fib_table_hash[h], tb_hlist) { 95 if (tb->tb_id == id) { 96 rcu_read_unlock(); 97 return tb; 98 } 99 } 100 rcu_read_unlock(); 101 return NULL; 102} 103#endif /* CONFIG_IP_MULTIPLE_TABLES */ 104 105static void fib_flush(void) 106{ 107 int flushed = 0; 108 struct fib_table *tb; 109 struct hlist_node *node; 110 unsigned int h; 111 112 for (h = 0; h < FIB_TABLE_HASHSZ; h++) { 113 hlist_for_each_entry(tb, node, &fib_table_hash[h], tb_hlist) 114 flushed += tb->tb_flush(tb); 115 } 116 117 if (flushed) 118 rt_cache_flush(-1); 119} 120 121/* 122 * Find the first device with a given source address. 123 */ 124 125struct net_device * ip_dev_find(u32 addr) 126{ 127 struct flowi fl = { .nl_u = { .ip4_u = { .daddr = addr } } }; 128 struct fib_result res; 129 struct net_device *dev = NULL; 130 131#ifdef CONFIG_IP_MULTIPLE_TABLES 132 res.r = NULL; 133#endif 134 135 if (!ip_fib_local_table || 136 ip_fib_local_table->tb_lookup(ip_fib_local_table, &fl, &res)) 137 return NULL; 138 if (res.type != RTN_LOCAL) 139 goto out; 140 dev = FIB_RES_DEV(res); 141 142 if (dev) 143 dev_hold(dev); 144out: 145 fib_res_put(&res); 146 return dev; 147} 148 149unsigned inet_addr_type(u32 addr) 150{ 151 struct flowi fl = { .nl_u = { .ip4_u = { .daddr = addr } } }; 152 struct fib_result res; 153 unsigned ret = RTN_BROADCAST; 154 155 if (ZERONET(addr) || BADCLASS(addr)) 156 return RTN_BROADCAST; 157 if (MULTICAST(addr)) 158 return RTN_MULTICAST; 159 160#ifdef CONFIG_IP_MULTIPLE_TABLES 161 res.r = NULL; 162#endif 163 164 if (ip_fib_local_table) { 165 ret = RTN_UNICAST; 166 if (!ip_fib_local_table->tb_lookup(ip_fib_local_table, 167 &fl, &res)) { 168 ret = res.type; 169 fib_res_put(&res); 170 } 171 } 172 return ret; 173} 174 175/* Given (packet source, input interface) and optional (dst, oif, tos): 176 - (main) check, that source is valid i.e. not broadcast or our local 177 address. 178 - figure out what "logical" interface this packet arrived 179 and calculate "specific destination" address. 180 - check, that packet arrived from expected physical interface. 181 */ 182 183int fib_validate_source(__be32 src, __be32 dst, u8 tos, int oif, 184 struct net_device *dev, __be32 *spec_dst, u32 *itag) 185{ 186 struct in_device *in_dev; 187 struct flowi fl = { .nl_u = { .ip4_u = 188 { .daddr = src, 189 .saddr = dst, 190 .tos = tos } }, 191 .iif = oif }; 192 struct fib_result res; 193 int no_addr, rpf; 194 int ret; 195 196 no_addr = rpf = 0; 197 rcu_read_lock(); 198 in_dev = __in_dev_get_rcu(dev); 199 if (in_dev) { 200 no_addr = in_dev->ifa_list == NULL; 201 rpf = IN_DEV_RPFILTER(in_dev); 202 } 203 rcu_read_unlock(); 204 205 if (in_dev == NULL) 206 goto e_inval; 207 208 if (fib_lookup(&fl, &res)) 209 goto last_resort; 210 if (res.type != RTN_UNICAST) 211 goto e_inval_res; 212 *spec_dst = FIB_RES_PREFSRC(res); 213 fib_combine_itag(itag, &res); 214#ifdef CONFIG_IP_ROUTE_MULTIPATH 215 if (FIB_RES_DEV(res) == dev || res.fi->fib_nhs > 1) 216#else 217 if (FIB_RES_DEV(res) == dev) 218#endif 219 { 220 ret = FIB_RES_NH(res).nh_scope >= RT_SCOPE_HOST; 221 fib_res_put(&res); 222 return ret; 223 } 224 fib_res_put(&res); 225 if (no_addr) 226 goto last_resort; 227 if (rpf) 228 goto e_inval; 229 fl.oif = dev->ifindex; 230 231 ret = 0; 232 if (fib_lookup(&fl, &res) == 0) { 233 if (res.type == RTN_UNICAST) { 234 *spec_dst = FIB_RES_PREFSRC(res); 235 ret = FIB_RES_NH(res).nh_scope >= RT_SCOPE_HOST; 236 } 237 fib_res_put(&res); 238 } 239 return ret; 240 241last_resort: 242 if (rpf) 243 goto e_inval; 244 *spec_dst = inet_select_addr(dev, 0, RT_SCOPE_UNIVERSE); 245 *itag = 0; 246 return 0; 247 248e_inval_res: 249 fib_res_put(&res); 250e_inval: 251 return -EINVAL; 252} 253 254#ifndef CONFIG_IP_NOSIOCRT 255 256static inline u32 sk_extract_addr(struct sockaddr *addr) 257{ 258 return ((struct sockaddr_in *) addr)->sin_addr.s_addr; 259} 260 261static int put_rtax(struct nlattr *mx, int len, int type, u32 value) 262{ 263 struct nlattr *nla; 264 265 nla = (struct nlattr *) ((char *) mx + len); 266 nla->nla_type = type; 267 nla->nla_len = nla_attr_size(4); 268 *(u32 *) nla_data(nla) = value; 269 270 return len + nla_total_size(4); 271} 272 273static int rtentry_to_fib_config(int cmd, struct rtentry *rt, 274 struct fib_config *cfg) 275{ 276 u32 addr; 277 int plen; 278 279 memset(cfg, 0, sizeof(*cfg)); 280 281 if (rt->rt_dst.sa_family != AF_INET) 282 return -EAFNOSUPPORT; 283 284 /* 285 * Check mask for validity: 286 * a) it must be contiguous. 287 * b) destination must have all host bits clear. 288 * c) if application forgot to set correct family (AF_INET), 289 * reject request unless it is absolutely clear i.e. 290 * both family and mask are zero. 291 */ 292 plen = 32; 293 addr = sk_extract_addr(&rt->rt_dst); 294 if (!(rt->rt_flags & RTF_HOST)) { 295 u32 mask = sk_extract_addr(&rt->rt_genmask); 296 297 if (rt->rt_genmask.sa_family != AF_INET) { 298 if (mask || rt->rt_genmask.sa_family) 299 return -EAFNOSUPPORT; 300 } 301 302 if (bad_mask(mask, addr)) 303 return -EINVAL; 304 305 plen = inet_mask_len(mask); 306 } 307 308 cfg->fc_dst_len = plen; 309 cfg->fc_dst = addr; 310 311 if (cmd != SIOCDELRT) { 312 cfg->fc_nlflags = NLM_F_CREATE; 313 cfg->fc_protocol = RTPROT_BOOT; 314 } 315 316 if (rt->rt_metric) 317 cfg->fc_priority = rt->rt_metric - 1; 318 319 if (rt->rt_flags & RTF_REJECT) { 320 cfg->fc_scope = RT_SCOPE_HOST; 321 cfg->fc_type = RTN_UNREACHABLE; 322 return 0; 323 } 324 325 cfg->fc_scope = RT_SCOPE_NOWHERE; 326 cfg->fc_type = RTN_UNICAST; 327 328 if (rt->rt_dev) { 329 char *colon; 330 struct net_device *dev; 331 char devname[IFNAMSIZ]; 332 333 if (copy_from_user(devname, rt->rt_dev, IFNAMSIZ-1)) 334 return -EFAULT; 335 336 devname[IFNAMSIZ-1] = 0; 337 colon = strchr(devname, ':'); 338 if (colon) 339 *colon = 0; 340 dev = __dev_get_by_name(devname); 341 if (!dev) 342 return -ENODEV; 343 cfg->fc_oif = dev->ifindex; 344 if (colon) { 345 struct in_ifaddr *ifa; 346 struct in_device *in_dev = __in_dev_get_rtnl(dev); 347 if (!in_dev) 348 return -ENODEV; 349 *colon = ':'; 350 for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) 351 if (strcmp(ifa->ifa_label, devname) == 0) 352 break; 353 if (ifa == NULL) 354 return -ENODEV; 355 cfg->fc_prefsrc = ifa->ifa_local; 356 } 357 } 358 359 addr = sk_extract_addr(&rt->rt_gateway); 360 if (rt->rt_gateway.sa_family == AF_INET && addr) { 361 cfg->fc_gw = addr; 362 if (rt->rt_flags & RTF_GATEWAY && 363 inet_addr_type(addr) == RTN_UNICAST) 364 cfg->fc_scope = RT_SCOPE_UNIVERSE; 365 } 366 367 if (cmd == SIOCDELRT) 368 return 0; 369 370 if (rt->rt_flags & RTF_GATEWAY && !cfg->fc_gw) 371 return -EINVAL; 372 373 if (cfg->fc_scope == RT_SCOPE_NOWHERE) 374 cfg->fc_scope = RT_SCOPE_LINK; 375 376 if (rt->rt_flags & (RTF_MTU | RTF_WINDOW | RTF_IRTT)) { 377 struct nlattr *mx; 378 int len = 0; 379 380 mx = kzalloc(3 * nla_total_size(4), GFP_KERNEL); 381 if (mx == NULL) 382 return -ENOMEM; 383 384 if (rt->rt_flags & RTF_MTU) 385 len = put_rtax(mx, len, RTAX_ADVMSS, rt->rt_mtu - 40); 386 387 if (rt->rt_flags & RTF_WINDOW) 388 len = put_rtax(mx, len, RTAX_WINDOW, rt->rt_window); 389 390 if (rt->rt_flags & RTF_IRTT) 391 len = put_rtax(mx, len, RTAX_RTT, rt->rt_irtt << 3); 392 393 cfg->fc_mx = mx; 394 cfg->fc_mx_len = len; 395 } 396 397 return 0; 398} 399 400/* 401 * Handle IP routing ioctl calls. These are used to manipulate the routing tables 402 */ 403 404int ip_rt_ioctl(unsigned int cmd, void __user *arg) 405{ 406 struct fib_config cfg; 407 struct rtentry rt; 408 int err; 409 410 switch (cmd) { 411 case SIOCADDRT: /* Add a route */ 412 case SIOCDELRT: /* Delete a route */ 413 if (!capable(CAP_NET_ADMIN)) 414 return -EPERM; 415 416 if (copy_from_user(&rt, arg, sizeof(rt))) 417 return -EFAULT; 418 419 rtnl_lock(); 420 err = rtentry_to_fib_config(cmd, &rt, &cfg); 421 if (err == 0) { 422 struct fib_table *tb; 423 424 if (cmd == SIOCDELRT) { 425 tb = fib_get_table(cfg.fc_table); 426 if (tb) 427 err = tb->tb_delete(tb, &cfg); 428 else 429 err = -ESRCH; 430 } else { 431 tb = fib_new_table(cfg.fc_table); 432 if (tb) 433 err = tb->tb_insert(tb, &cfg); 434 else 435 err = -ENOBUFS; 436 } 437 438 /* allocated by rtentry_to_fib_config() */ 439 kfree(cfg.fc_mx); 440 } 441 rtnl_unlock(); 442 return err; 443 } 444 return -EINVAL; 445} 446 447#else 448 449int ip_rt_ioctl(unsigned int cmd, void *arg) 450{ 451 return -EINVAL; 452} 453 454#endif 455 456struct nla_policy rtm_ipv4_policy[RTA_MAX+1] __read_mostly = { 457 [RTA_DST] = { .type = NLA_U32 }, 458 [RTA_SRC] = { .type = NLA_U32 }, 459 [RTA_IIF] = { .type = NLA_U32 }, 460 [RTA_OIF] = { .type = NLA_U32 }, 461 [RTA_GATEWAY] = { .type = NLA_U32 }, 462 [RTA_PRIORITY] = { .type = NLA_U32 }, 463 [RTA_PREFSRC] = { .type = NLA_U32 }, 464 [RTA_METRICS] = { .type = NLA_NESTED }, 465 [RTA_MULTIPATH] = { .len = sizeof(struct rtnexthop) }, 466 [RTA_PROTOINFO] = { .type = NLA_U32 }, 467 [RTA_FLOW] = { .type = NLA_U32 }, 468 [RTA_MP_ALGO] = { .type = NLA_U32 }, 469}; 470 471static int rtm_to_fib_config(struct sk_buff *skb, struct nlmsghdr *nlh, 472 struct fib_config *cfg) 473{ 474 struct nlattr *attr; 475 int err, remaining; 476 struct rtmsg *rtm; 477 478 err = nlmsg_validate(nlh, sizeof(*rtm), RTA_MAX, rtm_ipv4_policy); 479 if (err < 0) 480 goto errout; 481 482 memset(cfg, 0, sizeof(*cfg)); 483 484 rtm = nlmsg_data(nlh); 485 cfg->fc_family = rtm->rtm_family; 486 cfg->fc_dst_len = rtm->rtm_dst_len; 487 cfg->fc_src_len = rtm->rtm_src_len; 488 cfg->fc_tos = rtm->rtm_tos; 489 cfg->fc_table = rtm->rtm_table; 490 cfg->fc_protocol = rtm->rtm_protocol; 491 cfg->fc_scope = rtm->rtm_scope; 492 cfg->fc_type = rtm->rtm_type; 493 cfg->fc_flags = rtm->rtm_flags; 494 cfg->fc_nlflags = nlh->nlmsg_flags; 495 496 cfg->fc_nlinfo.pid = NETLINK_CB(skb).pid; 497 cfg->fc_nlinfo.nlh = nlh; 498 499 nlmsg_for_each_attr(attr, nlh, sizeof(struct rtmsg), remaining) { 500 switch (attr->nla_type) { 501 case RTA_DST: 502 cfg->fc_dst = nla_get_u32(attr); 503 break; 504 case RTA_SRC: 505 cfg->fc_src = nla_get_u32(attr); 506 break; 507 case RTA_OIF: 508 cfg->fc_oif = nla_get_u32(attr); 509 break; 510 case RTA_GATEWAY: 511 cfg->fc_gw = nla_get_u32(attr); 512 break; 513 case RTA_PRIORITY: 514 cfg->fc_priority = nla_get_u32(attr); 515 break; 516 case RTA_PREFSRC: 517 cfg->fc_prefsrc = nla_get_u32(attr); 518 break; 519 case RTA_METRICS: 520 cfg->fc_mx = nla_data(attr); 521 cfg->fc_mx_len = nla_len(attr); 522 break; 523 case RTA_MULTIPATH: 524 cfg->fc_mp = nla_data(attr); 525 cfg->fc_mp_len = nla_len(attr); 526 break; 527 case RTA_FLOW: 528 cfg->fc_flow = nla_get_u32(attr); 529 break; 530 case RTA_MP_ALGO: 531 cfg->fc_mp_alg = nla_get_u32(attr); 532 break; 533 case RTA_TABLE: 534 cfg->fc_table = nla_get_u32(attr); 535 break; 536 } 537 } 538 539 return 0; 540errout: 541 return err; 542} 543 544int inet_rtm_delroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg) 545{ 546 struct fib_config cfg; 547 struct fib_table *tb; 548 int err; 549 550 err = rtm_to_fib_config(skb, nlh, &cfg); 551 if (err < 0) 552 goto errout; 553 554 tb = fib_get_table(cfg.fc_table); 555 if (tb == NULL) { 556 err = -ESRCH; 557 goto errout; 558 } 559 560 err = tb->tb_delete(tb, &cfg); 561errout: 562 return err; 563} 564 565int inet_rtm_newroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg) 566{ 567 struct fib_config cfg; 568 struct fib_table *tb; 569 int err; 570 571 err = rtm_to_fib_config(skb, nlh, &cfg); 572 if (err < 0) 573 goto errout; 574 575 tb = fib_new_table(cfg.fc_table); 576 if (tb == NULL) { 577 err = -ENOBUFS; 578 goto errout; 579 } 580 581 err = tb->tb_insert(tb, &cfg); 582errout: 583 return err; 584} 585 586int inet_dump_fib(struct sk_buff *skb, struct netlink_callback *cb) 587{ 588 unsigned int h, s_h; 589 unsigned int e = 0, s_e; 590 struct fib_table *tb; 591 struct hlist_node *node; 592 int dumped = 0; 593 594 if (nlmsg_len(cb->nlh) >= sizeof(struct rtmsg) && 595 ((struct rtmsg *) nlmsg_data(cb->nlh))->rtm_flags & RTM_F_CLONED) 596 return ip_rt_dump(skb, cb); 597 598 s_h = cb->args[0]; 599 s_e = cb->args[1]; 600 601 for (h = s_h; h < FIB_TABLE_HASHSZ; h++, s_e = 0) { 602 e = 0; 603 hlist_for_each_entry(tb, node, &fib_table_hash[h], tb_hlist) { 604 if (e < s_e) 605 goto next; 606 if (dumped) 607 memset(&cb->args[2], 0, sizeof(cb->args) - 608 2 * sizeof(cb->args[0])); 609 if (tb->tb_dump(tb, skb, cb) < 0) 610 goto out; 611 dumped = 1; 612next: 613 e++; 614 } 615 } 616out: 617 cb->args[1] = e; 618 cb->args[0] = h; 619 620 return skb->len; 621} 622 623/* Prepare and feed intra-kernel routing request. 624 Really, it should be netlink message, but :-( netlink 625 can be not configured, so that we feed it directly 626 to fib engine. It is legal, because all events occur 627 only when netlink is already locked. 628 */ 629 630static void fib_magic(int cmd, int type, u32 dst, int dst_len, 631 struct in_ifaddr *ifa) 632{ 633 struct fib_table *tb; 634 struct fib_config cfg = { 635 .fc_protocol = RTPROT_KERNEL, 636 .fc_type = type, 637 .fc_dst = dst, 638 .fc_dst_len = dst_len, 639 .fc_prefsrc = ifa->ifa_local, 640 .fc_oif = ifa->ifa_dev->dev->ifindex, 641 .fc_nlflags = NLM_F_CREATE | NLM_F_APPEND, 642 }; 643 644 if (type == RTN_UNICAST) 645 tb = fib_new_table(RT_TABLE_MAIN); 646 else 647 tb = fib_new_table(RT_TABLE_LOCAL); 648 649 if (tb == NULL) 650 return; 651 652 cfg.fc_table = tb->tb_id; 653 654 if (type != RTN_LOCAL) 655 cfg.fc_scope = RT_SCOPE_LINK; 656 else 657 cfg.fc_scope = RT_SCOPE_HOST; 658 659 if (cmd == RTM_NEWROUTE) 660 tb->tb_insert(tb, &cfg); 661 else 662 tb->tb_delete(tb, &cfg); 663} 664 665void fib_add_ifaddr(struct in_ifaddr *ifa) 666{ 667 struct in_device *in_dev = ifa->ifa_dev; 668 struct net_device *dev = in_dev->dev; 669 struct in_ifaddr *prim = ifa; 670 u32 mask = ifa->ifa_mask; 671 u32 addr = ifa->ifa_local; 672 u32 prefix = ifa->ifa_address&mask; 673 674 if (ifa->ifa_flags&IFA_F_SECONDARY) { 675 prim = inet_ifa_byprefix(in_dev, prefix, mask); 676 if (prim == NULL) { 677 printk(KERN_DEBUG "fib_add_ifaddr: bug: prim == NULL\n"); 678 return; 679 } 680 } 681 682 fib_magic(RTM_NEWROUTE, RTN_LOCAL, addr, 32, prim); 683 684 if (!(dev->flags&IFF_UP)) 685 return; 686 687 /* Add broadcast address, if it is explicitly assigned. */ 688 if (ifa->ifa_broadcast && ifa->ifa_broadcast != 0xFFFFFFFF) 689 fib_magic(RTM_NEWROUTE, RTN_BROADCAST, ifa->ifa_broadcast, 32, prim); 690 691 if (!ZERONET(prefix) && !(ifa->ifa_flags&IFA_F_SECONDARY) && 692 (prefix != addr || ifa->ifa_prefixlen < 32)) { 693 fib_magic(RTM_NEWROUTE, dev->flags&IFF_LOOPBACK ? RTN_LOCAL : 694 RTN_UNICAST, prefix, ifa->ifa_prefixlen, prim); 695 696 /* Add network specific broadcasts, when it takes a sense */ 697 if (ifa->ifa_prefixlen < 31) { 698 fib_magic(RTM_NEWROUTE, RTN_BROADCAST, prefix, 32, prim); 699 fib_magic(RTM_NEWROUTE, RTN_BROADCAST, prefix|~mask, 32, prim); 700 } 701 } 702} 703 704static void fib_del_ifaddr(struct in_ifaddr *ifa) 705{ 706 struct in_device *in_dev = ifa->ifa_dev; 707 struct net_device *dev = in_dev->dev; 708 struct in_ifaddr *ifa1; 709 struct in_ifaddr *prim = ifa; 710 u32 brd = ifa->ifa_address|~ifa->ifa_mask; 711 u32 any = ifa->ifa_address&ifa->ifa_mask; 712#define LOCAL_OK 1 713#define BRD_OK 2 714#define BRD0_OK 4 715#define BRD1_OK 8 716 unsigned ok = 0; 717 718 if (!(ifa->ifa_flags&IFA_F_SECONDARY)) 719 fib_magic(RTM_DELROUTE, dev->flags&IFF_LOOPBACK ? RTN_LOCAL : 720 RTN_UNICAST, any, ifa->ifa_prefixlen, prim); 721 else { 722 prim = inet_ifa_byprefix(in_dev, any, ifa->ifa_mask); 723 if (prim == NULL) { 724 printk(KERN_DEBUG "fib_del_ifaddr: bug: prim == NULL\n"); 725 return; 726 } 727 } 728 729 /* Deletion is more complicated than add. 730 We should take care of not to delete too much :-) 731 732 Scan address list to be sure that addresses are really gone. 733 */ 734 735 for (ifa1 = in_dev->ifa_list; ifa1; ifa1 = ifa1->ifa_next) { 736 if (ifa->ifa_local == ifa1->ifa_local) 737 ok |= LOCAL_OK; 738 if (ifa->ifa_broadcast == ifa1->ifa_broadcast) 739 ok |= BRD_OK; 740 if (brd == ifa1->ifa_broadcast) 741 ok |= BRD1_OK; 742 if (any == ifa1->ifa_broadcast) 743 ok |= BRD0_OK; 744 } 745 746 if (!(ok&BRD_OK)) 747 fib_magic(RTM_DELROUTE, RTN_BROADCAST, ifa->ifa_broadcast, 32, prim); 748 if (!(ok&BRD1_OK)) 749 fib_magic(RTM_DELROUTE, RTN_BROADCAST, brd, 32, prim); 750 if (!(ok&BRD0_OK)) 751 fib_magic(RTM_DELROUTE, RTN_BROADCAST, any, 32, prim); 752 if (!(ok&LOCAL_OK)) { 753 fib_magic(RTM_DELROUTE, RTN_LOCAL, ifa->ifa_local, 32, prim); 754 755 /* Check, that this local address finally disappeared. */ 756 if (inet_addr_type(ifa->ifa_local) != RTN_LOCAL) { 757 /* And the last, but not the least thing. 758 We must flush stray FIB entries. 759 760 First of all, we scan fib_info list searching 761 for stray nexthop entries, then ignite fib_flush. 762 */ 763 if (fib_sync_down(ifa->ifa_local, NULL, 0)) 764 fib_flush(); 765 } 766 } 767#undef LOCAL_OK 768#undef BRD_OK 769#undef BRD0_OK 770#undef BRD1_OK 771} 772 773static void nl_fib_lookup(struct fib_result_nl *frn, struct fib_table *tb ) 774{ 775 776 struct fib_result res; 777 struct flowi fl = { .nl_u = { .ip4_u = { .daddr = frn->fl_addr, 778 .fwmark = frn->fl_fwmark, 779 .tos = frn->fl_tos, 780 .scope = frn->fl_scope } } }; 781 if (tb) { 782 local_bh_disable(); 783 784 frn->tb_id = tb->tb_id; 785 frn->err = tb->tb_lookup(tb, &fl, &res); 786 787 if (!frn->err) { 788 frn->prefixlen = res.prefixlen; 789 frn->nh_sel = res.nh_sel; 790 frn->type = res.type; 791 frn->scope = res.scope; 792 } 793 local_bh_enable(); 794 } 795} 796 797static void nl_fib_input(struct sock *sk, int len) 798{ 799 struct sk_buff *skb = NULL; 800 struct nlmsghdr *nlh = NULL; 801 struct fib_result_nl *frn; 802 u32 pid; 803 struct fib_table *tb; 804 805 skb = skb_dequeue(&sk->sk_receive_queue); 806 nlh = (struct nlmsghdr *)skb->data; 807 if (skb->len < NLMSG_SPACE(0) || skb->len < nlh->nlmsg_len || 808 nlh->nlmsg_len < NLMSG_LENGTH(sizeof(*frn))) { 809 kfree_skb(skb); 810 return; 811 } 812 813 frn = (struct fib_result_nl *) NLMSG_DATA(nlh); 814 tb = fib_get_table(frn->tb_id_in); 815 816 nl_fib_lookup(frn, tb); 817 818 pid = nlh->nlmsg_pid; /*pid of sending process */ 819 NETLINK_CB(skb).pid = 0; /* from kernel */ 820 NETLINK_CB(skb).dst_pid = pid; 821 NETLINK_CB(skb).dst_group = 0; /* unicast */ 822 netlink_unicast(sk, skb, pid, MSG_DONTWAIT); 823} 824 825static void nl_fib_lookup_init(void) 826{ 827 netlink_kernel_create(NETLINK_FIB_LOOKUP, 0, nl_fib_input, THIS_MODULE); 828} 829 830static void fib_disable_ip(struct net_device *dev, int force) 831{ 832 if (fib_sync_down(0, dev, force)) 833 fib_flush(); 834 rt_cache_flush(0); 835 arp_ifdown(dev); 836} 837 838static int fib_inetaddr_event(struct notifier_block *this, unsigned long event, void *ptr) 839{ 840 struct in_ifaddr *ifa = (struct in_ifaddr*)ptr; 841 842 switch (event) { 843 case NETDEV_UP: 844 fib_add_ifaddr(ifa); 845#ifdef CONFIG_IP_ROUTE_MULTIPATH 846 fib_sync_up(ifa->ifa_dev->dev); 847#endif 848 rt_cache_flush(-1); 849 break; 850 case NETDEV_DOWN: 851 fib_del_ifaddr(ifa); 852 if (ifa->ifa_dev->ifa_list == NULL) { 853 /* Last address was deleted from this interface. 854 Disable IP. 855 */ 856 fib_disable_ip(ifa->ifa_dev->dev, 1); 857 } else { 858 rt_cache_flush(-1); 859 } 860 break; 861 } 862 return NOTIFY_DONE; 863} 864 865static int fib_netdev_event(struct notifier_block *this, unsigned long event, void *ptr) 866{ 867 struct net_device *dev = ptr; 868 struct in_device *in_dev = __in_dev_get_rtnl(dev); 869 870 if (event == NETDEV_UNREGISTER) { 871 fib_disable_ip(dev, 2); 872 return NOTIFY_DONE; 873 } 874 875 if (!in_dev) 876 return NOTIFY_DONE; 877 878 switch (event) { 879 case NETDEV_UP: 880 for_ifa(in_dev) { 881 fib_add_ifaddr(ifa); 882 } endfor_ifa(in_dev); 883#ifdef CONFIG_IP_ROUTE_MULTIPATH 884 fib_sync_up(dev); 885#endif 886 rt_cache_flush(-1); 887 break; 888 case NETDEV_DOWN: 889 fib_disable_ip(dev, 0); 890 break; 891 case NETDEV_CHANGEMTU: 892 case NETDEV_CHANGE: 893 rt_cache_flush(0); 894 break; 895 } 896 return NOTIFY_DONE; 897} 898 899static struct notifier_block fib_inetaddr_notifier = { 900 .notifier_call =fib_inetaddr_event, 901}; 902 903static struct notifier_block fib_netdev_notifier = { 904 .notifier_call =fib_netdev_event, 905}; 906 907void __init ip_fib_init(void) 908{ 909 unsigned int i; 910 911 for (i = 0; i < FIB_TABLE_HASHSZ; i++) 912 INIT_HLIST_HEAD(&fib_table_hash[i]); 913#ifndef CONFIG_IP_MULTIPLE_TABLES 914 ip_fib_local_table = fib_hash_init(RT_TABLE_LOCAL); 915 hlist_add_head_rcu(&ip_fib_local_table->tb_hlist, &fib_table_hash[0]); 916 ip_fib_main_table = fib_hash_init(RT_TABLE_MAIN); 917 hlist_add_head_rcu(&ip_fib_main_table->tb_hlist, &fib_table_hash[0]); 918#else 919 fib4_rules_init(); 920#endif 921 922 register_netdevice_notifier(&fib_netdev_notifier); 923 register_inetaddr_notifier(&fib_inetaddr_notifier); 924 nl_fib_lookup_init(); 925} 926 927EXPORT_SYMBOL(inet_addr_type); 928EXPORT_SYMBOL(ip_dev_find); 929