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