1 /* 2 * Neighbour Discovery for IPv6 3 * Linux INET6 implementation 4 * 5 * Authors: 6 * Pedro Roque <roque@di.fc.ul.pt> 7 * Mike Shaver <shaver@ingenia.com> 8 * 9 * This program is free software; you can redistribute it and/or 10 * modify it under the terms of the GNU General Public License 11 * as published by the Free Software Foundation; either version 12 * 2 of the License, or (at your option) any later version. 13 */ 14 15 /* 16 * Changes: 17 * 18 * Alexey I. Froloff : RFC6106 (DNSSL) support 19 * Pierre Ynard : export userland ND options 20 * through netlink (RDNSS support) 21 * Lars Fenneberg : fixed MTU setting on receipt 22 * of an RA. 23 * Janos Farkas : kmalloc failure checks 24 * Alexey Kuznetsov : state machine reworked 25 * and moved to net/core. 26 * Pekka Savola : RFC2461 validation 27 * YOSHIFUJI Hideaki @USAGI : Verify ND options properly 28 */ 29 30 #define pr_fmt(fmt) "ICMPv6: " fmt 31 32 #include <linux/module.h> 33 #include <linux/errno.h> 34 #include <linux/types.h> 35 #include <linux/socket.h> 36 #include <linux/sockios.h> 37 #include <linux/sched.h> 38 #include <linux/net.h> 39 #include <linux/in6.h> 40 #include <linux/route.h> 41 #include <linux/init.h> 42 #include <linux/rcupdate.h> 43 #include <linux/slab.h> 44 #ifdef CONFIG_SYSCTL 45 #include <linux/sysctl.h> 46 #endif 47 48 #include <linux/if_addr.h> 49 #include <linux/if_ether.h> 50 #include <linux/if_arp.h> 51 #include <linux/ipv6.h> 52 #include <linux/icmpv6.h> 53 #include <linux/jhash.h> 54 55 #include <net/sock.h> 56 #include <net/snmp.h> 57 58 #include <net/ipv6.h> 59 #include <net/protocol.h> 60 #include <net/ndisc.h> 61 #include <net/ip6_route.h> 62 #include <net/addrconf.h> 63 #include <net/icmp.h> 64 65 #include <net/netlink.h> 66 #include <linux/rtnetlink.h> 67 68 #include <net/flow.h> 69 #include <net/ip6_checksum.h> 70 #include <net/inet_common.h> 71 #include <linux/proc_fs.h> 72 73 #include <linux/netfilter.h> 74 #include <linux/netfilter_ipv6.h> 75 76 static u32 ndisc_hash(const void *pkey, 77 const struct net_device *dev, 78 __u32 *hash_rnd); 79 static bool ndisc_key_eq(const struct neighbour *neigh, const void *pkey); 80 static int ndisc_constructor(struct neighbour *neigh); 81 static void ndisc_solicit(struct neighbour *neigh, struct sk_buff *skb); 82 static void ndisc_error_report(struct neighbour *neigh, struct sk_buff *skb); 83 static int pndisc_constructor(struct pneigh_entry *n); 84 static void pndisc_destructor(struct pneigh_entry *n); 85 static void pndisc_redo(struct sk_buff *skb); 86 87 static const struct neigh_ops ndisc_generic_ops = { 88 .family = AF_INET6, 89 .solicit = ndisc_solicit, 90 .error_report = ndisc_error_report, 91 .output = neigh_resolve_output, 92 .connected_output = neigh_connected_output, 93 }; 94 95 static const struct neigh_ops ndisc_hh_ops = { 96 .family = AF_INET6, 97 .solicit = ndisc_solicit, 98 .error_report = ndisc_error_report, 99 .output = neigh_resolve_output, 100 .connected_output = neigh_resolve_output, 101 }; 102 103 104 static const struct neigh_ops ndisc_direct_ops = { 105 .family = AF_INET6, 106 .output = neigh_direct_output, 107 .connected_output = neigh_direct_output, 108 }; 109 110 struct neigh_table nd_tbl = { 111 .family = AF_INET6, 112 .key_len = sizeof(struct in6_addr), 113 .protocol = cpu_to_be16(ETH_P_IPV6), 114 .hash = ndisc_hash, 115 .key_eq = ndisc_key_eq, 116 .constructor = ndisc_constructor, 117 .pconstructor = pndisc_constructor, 118 .pdestructor = pndisc_destructor, 119 .proxy_redo = pndisc_redo, 120 .id = "ndisc_cache", 121 .parms = { 122 .tbl = &nd_tbl, 123 .reachable_time = ND_REACHABLE_TIME, 124 .data = { 125 [NEIGH_VAR_MCAST_PROBES] = 3, 126 [NEIGH_VAR_UCAST_PROBES] = 3, 127 [NEIGH_VAR_RETRANS_TIME] = ND_RETRANS_TIMER, 128 [NEIGH_VAR_BASE_REACHABLE_TIME] = ND_REACHABLE_TIME, 129 [NEIGH_VAR_DELAY_PROBE_TIME] = 5 * HZ, 130 [NEIGH_VAR_GC_STALETIME] = 60 * HZ, 131 [NEIGH_VAR_QUEUE_LEN_BYTES] = SK_WMEM_MAX, 132 [NEIGH_VAR_PROXY_QLEN] = 64, 133 [NEIGH_VAR_ANYCAST_DELAY] = 1 * HZ, 134 [NEIGH_VAR_PROXY_DELAY] = (8 * HZ) / 10, 135 }, 136 }, 137 .gc_interval = 30 * HZ, 138 .gc_thresh1 = 128, 139 .gc_thresh2 = 512, 140 .gc_thresh3 = 1024, 141 }; 142 EXPORT_SYMBOL_GPL(nd_tbl); 143 144 void __ndisc_fill_addr_option(struct sk_buff *skb, int type, void *data, 145 int data_len, int pad) 146 { 147 int space = __ndisc_opt_addr_space(data_len, pad); 148 u8 *opt = skb_put(skb, space); 149 150 opt[0] = type; 151 opt[1] = space>>3; 152 153 memset(opt + 2, 0, pad); 154 opt += pad; 155 space -= pad; 156 157 memcpy(opt+2, data, data_len); 158 data_len += 2; 159 opt += data_len; 160 space -= data_len; 161 if (space > 0) 162 memset(opt, 0, space); 163 } 164 EXPORT_SYMBOL_GPL(__ndisc_fill_addr_option); 165 166 static inline void ndisc_fill_addr_option(struct sk_buff *skb, int type, 167 void *data, u8 icmp6_type) 168 { 169 __ndisc_fill_addr_option(skb, type, data, skb->dev->addr_len, 170 ndisc_addr_option_pad(skb->dev->type)); 171 ndisc_ops_fill_addr_option(skb->dev, skb, icmp6_type); 172 } 173 174 static inline void ndisc_fill_redirect_addr_option(struct sk_buff *skb, 175 void *ha, 176 const u8 *ops_data) 177 { 178 ndisc_fill_addr_option(skb, ND_OPT_TARGET_LL_ADDR, ha, NDISC_REDIRECT); 179 ndisc_ops_fill_redirect_addr_option(skb->dev, skb, ops_data); 180 } 181 182 static struct nd_opt_hdr *ndisc_next_option(struct nd_opt_hdr *cur, 183 struct nd_opt_hdr *end) 184 { 185 int type; 186 if (!cur || !end || cur >= end) 187 return NULL; 188 type = cur->nd_opt_type; 189 do { 190 cur = ((void *)cur) + (cur->nd_opt_len << 3); 191 } while (cur < end && cur->nd_opt_type != type); 192 return cur <= end && cur->nd_opt_type == type ? cur : NULL; 193 } 194 195 static inline int ndisc_is_useropt(const struct net_device *dev, 196 struct nd_opt_hdr *opt) 197 { 198 return opt->nd_opt_type == ND_OPT_RDNSS || 199 opt->nd_opt_type == ND_OPT_DNSSL || 200 ndisc_ops_is_useropt(dev, opt->nd_opt_type); 201 } 202 203 static struct nd_opt_hdr *ndisc_next_useropt(const struct net_device *dev, 204 struct nd_opt_hdr *cur, 205 struct nd_opt_hdr *end) 206 { 207 if (!cur || !end || cur >= end) 208 return NULL; 209 do { 210 cur = ((void *)cur) + (cur->nd_opt_len << 3); 211 } while (cur < end && !ndisc_is_useropt(dev, cur)); 212 return cur <= end && ndisc_is_useropt(dev, cur) ? cur : NULL; 213 } 214 215 struct ndisc_options *ndisc_parse_options(const struct net_device *dev, 216 u8 *opt, int opt_len, 217 struct ndisc_options *ndopts) 218 { 219 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)opt; 220 221 if (!nd_opt || opt_len < 0 || !ndopts) 222 return NULL; 223 memset(ndopts, 0, sizeof(*ndopts)); 224 while (opt_len) { 225 int l; 226 if (opt_len < sizeof(struct nd_opt_hdr)) 227 return NULL; 228 l = nd_opt->nd_opt_len << 3; 229 if (opt_len < l || l == 0) 230 return NULL; 231 if (ndisc_ops_parse_options(dev, nd_opt, ndopts)) 232 goto next_opt; 233 switch (nd_opt->nd_opt_type) { 234 case ND_OPT_SOURCE_LL_ADDR: 235 case ND_OPT_TARGET_LL_ADDR: 236 case ND_OPT_MTU: 237 case ND_OPT_NONCE: 238 case ND_OPT_REDIRECT_HDR: 239 if (ndopts->nd_opt_array[nd_opt->nd_opt_type]) { 240 ND_PRINTK(2, warn, 241 "%s: duplicated ND6 option found: type=%d\n", 242 __func__, nd_opt->nd_opt_type); 243 } else { 244 ndopts->nd_opt_array[nd_opt->nd_opt_type] = nd_opt; 245 } 246 break; 247 case ND_OPT_PREFIX_INFO: 248 ndopts->nd_opts_pi_end = nd_opt; 249 if (!ndopts->nd_opt_array[nd_opt->nd_opt_type]) 250 ndopts->nd_opt_array[nd_opt->nd_opt_type] = nd_opt; 251 break; 252 #ifdef CONFIG_IPV6_ROUTE_INFO 253 case ND_OPT_ROUTE_INFO: 254 ndopts->nd_opts_ri_end = nd_opt; 255 if (!ndopts->nd_opts_ri) 256 ndopts->nd_opts_ri = nd_opt; 257 break; 258 #endif 259 default: 260 if (ndisc_is_useropt(dev, nd_opt)) { 261 ndopts->nd_useropts_end = nd_opt; 262 if (!ndopts->nd_useropts) 263 ndopts->nd_useropts = nd_opt; 264 } else { 265 /* 266 * Unknown options must be silently ignored, 267 * to accommodate future extension to the 268 * protocol. 269 */ 270 ND_PRINTK(2, notice, 271 "%s: ignored unsupported option; type=%d, len=%d\n", 272 __func__, 273 nd_opt->nd_opt_type, 274 nd_opt->nd_opt_len); 275 } 276 } 277 next_opt: 278 opt_len -= l; 279 nd_opt = ((void *)nd_opt) + l; 280 } 281 return ndopts; 282 } 283 284 int ndisc_mc_map(const struct in6_addr *addr, char *buf, struct net_device *dev, int dir) 285 { 286 switch (dev->type) { 287 case ARPHRD_ETHER: 288 case ARPHRD_IEEE802: /* Not sure. Check it later. --ANK */ 289 case ARPHRD_FDDI: 290 ipv6_eth_mc_map(addr, buf); 291 return 0; 292 case ARPHRD_ARCNET: 293 ipv6_arcnet_mc_map(addr, buf); 294 return 0; 295 case ARPHRD_INFINIBAND: 296 ipv6_ib_mc_map(addr, dev->broadcast, buf); 297 return 0; 298 case ARPHRD_IPGRE: 299 return ipv6_ipgre_mc_map(addr, dev->broadcast, buf); 300 default: 301 if (dir) { 302 memcpy(buf, dev->broadcast, dev->addr_len); 303 return 0; 304 } 305 } 306 return -EINVAL; 307 } 308 EXPORT_SYMBOL(ndisc_mc_map); 309 310 static u32 ndisc_hash(const void *pkey, 311 const struct net_device *dev, 312 __u32 *hash_rnd) 313 { 314 return ndisc_hashfn(pkey, dev, hash_rnd); 315 } 316 317 static bool ndisc_key_eq(const struct neighbour *n, const void *pkey) 318 { 319 return neigh_key_eq128(n, pkey); 320 } 321 322 static int ndisc_constructor(struct neighbour *neigh) 323 { 324 struct in6_addr *addr = (struct in6_addr *)&neigh->primary_key; 325 struct net_device *dev = neigh->dev; 326 struct inet6_dev *in6_dev; 327 struct neigh_parms *parms; 328 bool is_multicast = ipv6_addr_is_multicast(addr); 329 330 in6_dev = in6_dev_get(dev); 331 if (!in6_dev) { 332 return -EINVAL; 333 } 334 335 parms = in6_dev->nd_parms; 336 __neigh_parms_put(neigh->parms); 337 neigh->parms = neigh_parms_clone(parms); 338 339 neigh->type = is_multicast ? RTN_MULTICAST : RTN_UNICAST; 340 if (!dev->header_ops) { 341 neigh->nud_state = NUD_NOARP; 342 neigh->ops = &ndisc_direct_ops; 343 neigh->output = neigh_direct_output; 344 } else { 345 if (is_multicast) { 346 neigh->nud_state = NUD_NOARP; 347 ndisc_mc_map(addr, neigh->ha, dev, 1); 348 } else if (dev->flags&(IFF_NOARP|IFF_LOOPBACK)) { 349 neigh->nud_state = NUD_NOARP; 350 memcpy(neigh->ha, dev->dev_addr, dev->addr_len); 351 if (dev->flags&IFF_LOOPBACK) 352 neigh->type = RTN_LOCAL; 353 } else if (dev->flags&IFF_POINTOPOINT) { 354 neigh->nud_state = NUD_NOARP; 355 memcpy(neigh->ha, dev->broadcast, dev->addr_len); 356 } 357 if (dev->header_ops->cache) 358 neigh->ops = &ndisc_hh_ops; 359 else 360 neigh->ops = &ndisc_generic_ops; 361 if (neigh->nud_state&NUD_VALID) 362 neigh->output = neigh->ops->connected_output; 363 else 364 neigh->output = neigh->ops->output; 365 } 366 in6_dev_put(in6_dev); 367 return 0; 368 } 369 370 static int pndisc_constructor(struct pneigh_entry *n) 371 { 372 struct in6_addr *addr = (struct in6_addr *)&n->key; 373 struct in6_addr maddr; 374 struct net_device *dev = n->dev; 375 376 if (!dev || !__in6_dev_get(dev)) 377 return -EINVAL; 378 addrconf_addr_solict_mult(addr, &maddr); 379 ipv6_dev_mc_inc(dev, &maddr); 380 return 0; 381 } 382 383 static void pndisc_destructor(struct pneigh_entry *n) 384 { 385 struct in6_addr *addr = (struct in6_addr *)&n->key; 386 struct in6_addr maddr; 387 struct net_device *dev = n->dev; 388 389 if (!dev || !__in6_dev_get(dev)) 390 return; 391 addrconf_addr_solict_mult(addr, &maddr); 392 ipv6_dev_mc_dec(dev, &maddr); 393 } 394 395 static struct sk_buff *ndisc_alloc_skb(struct net_device *dev, 396 int len) 397 { 398 int hlen = LL_RESERVED_SPACE(dev); 399 int tlen = dev->needed_tailroom; 400 struct sock *sk = dev_net(dev)->ipv6.ndisc_sk; 401 struct sk_buff *skb; 402 403 skb = alloc_skb(hlen + sizeof(struct ipv6hdr) + len + tlen, GFP_ATOMIC); 404 if (!skb) { 405 ND_PRINTK(0, err, "ndisc: %s failed to allocate an skb\n", 406 __func__); 407 return NULL; 408 } 409 410 skb->protocol = htons(ETH_P_IPV6); 411 skb->dev = dev; 412 413 skb_reserve(skb, hlen + sizeof(struct ipv6hdr)); 414 skb_reset_transport_header(skb); 415 416 /* Manually assign socket ownership as we avoid calling 417 * sock_alloc_send_pskb() to bypass wmem buffer limits 418 */ 419 skb_set_owner_w(skb, sk); 420 421 return skb; 422 } 423 424 static void ip6_nd_hdr(struct sk_buff *skb, 425 const struct in6_addr *saddr, 426 const struct in6_addr *daddr, 427 int hop_limit, int len) 428 { 429 struct ipv6hdr *hdr; 430 struct inet6_dev *idev; 431 unsigned tclass; 432 433 rcu_read_lock(); 434 idev = __in6_dev_get(skb->dev); 435 tclass = idev ? idev->cnf.ndisc_tclass : 0; 436 rcu_read_unlock(); 437 438 skb_push(skb, sizeof(*hdr)); 439 skb_reset_network_header(skb); 440 hdr = ipv6_hdr(skb); 441 442 ip6_flow_hdr(hdr, tclass, 0); 443 444 hdr->payload_len = htons(len); 445 hdr->nexthdr = IPPROTO_ICMPV6; 446 hdr->hop_limit = hop_limit; 447 448 hdr->saddr = *saddr; 449 hdr->daddr = *daddr; 450 } 451 452 static void ndisc_send_skb(struct sk_buff *skb, 453 const struct in6_addr *daddr, 454 const struct in6_addr *saddr) 455 { 456 struct dst_entry *dst = skb_dst(skb); 457 struct net *net = dev_net(skb->dev); 458 struct sock *sk = net->ipv6.ndisc_sk; 459 struct inet6_dev *idev; 460 int err; 461 struct icmp6hdr *icmp6h = icmp6_hdr(skb); 462 u8 type; 463 464 type = icmp6h->icmp6_type; 465 466 if (!dst) { 467 struct flowi6 fl6; 468 int oif = skb->dev->ifindex; 469 470 icmpv6_flow_init(sk, &fl6, type, saddr, daddr, oif); 471 dst = icmp6_dst_alloc(skb->dev, &fl6); 472 if (IS_ERR(dst)) { 473 kfree_skb(skb); 474 return; 475 } 476 477 skb_dst_set(skb, dst); 478 } 479 480 icmp6h->icmp6_cksum = csum_ipv6_magic(saddr, daddr, skb->len, 481 IPPROTO_ICMPV6, 482 csum_partial(icmp6h, 483 skb->len, 0)); 484 485 ip6_nd_hdr(skb, saddr, daddr, inet6_sk(sk)->hop_limit, skb->len); 486 487 rcu_read_lock(); 488 idev = __in6_dev_get(dst->dev); 489 IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUT, skb->len); 490 491 err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT, 492 net, sk, skb, NULL, dst->dev, 493 dst_output); 494 if (!err) { 495 ICMP6MSGOUT_INC_STATS(net, idev, type); 496 ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS); 497 } 498 499 rcu_read_unlock(); 500 } 501 502 void ndisc_send_na(struct net_device *dev, const struct in6_addr *daddr, 503 const struct in6_addr *solicited_addr, 504 bool router, bool solicited, bool override, bool inc_opt) 505 { 506 struct sk_buff *skb; 507 struct in6_addr tmpaddr; 508 struct inet6_ifaddr *ifp; 509 const struct in6_addr *src_addr; 510 struct nd_msg *msg; 511 int optlen = 0; 512 513 /* for anycast or proxy, solicited_addr != src_addr */ 514 ifp = ipv6_get_ifaddr(dev_net(dev), solicited_addr, dev, 1); 515 if (ifp) { 516 src_addr = solicited_addr; 517 if (ifp->flags & IFA_F_OPTIMISTIC) 518 override = false; 519 inc_opt |= ifp->idev->cnf.force_tllao; 520 in6_ifa_put(ifp); 521 } else { 522 if (ipv6_dev_get_saddr(dev_net(dev), dev, daddr, 523 inet6_sk(dev_net(dev)->ipv6.ndisc_sk)->srcprefs, 524 &tmpaddr)) 525 return; 526 src_addr = &tmpaddr; 527 } 528 529 if (!dev->addr_len) 530 inc_opt = false; 531 if (inc_opt) 532 optlen += ndisc_opt_addr_space(dev, 533 NDISC_NEIGHBOUR_ADVERTISEMENT); 534 535 skb = ndisc_alloc_skb(dev, sizeof(*msg) + optlen); 536 if (!skb) 537 return; 538 539 msg = skb_put(skb, sizeof(*msg)); 540 *msg = (struct nd_msg) { 541 .icmph = { 542 .icmp6_type = NDISC_NEIGHBOUR_ADVERTISEMENT, 543 .icmp6_router = router, 544 .icmp6_solicited = solicited, 545 .icmp6_override = override, 546 }, 547 .target = *solicited_addr, 548 }; 549 550 if (inc_opt) 551 ndisc_fill_addr_option(skb, ND_OPT_TARGET_LL_ADDR, 552 dev->dev_addr, 553 NDISC_NEIGHBOUR_ADVERTISEMENT); 554 555 ndisc_send_skb(skb, daddr, src_addr); 556 } 557 558 static void ndisc_send_unsol_na(struct net_device *dev) 559 { 560 struct inet6_dev *idev; 561 struct inet6_ifaddr *ifa; 562 563 idev = in6_dev_get(dev); 564 if (!idev) 565 return; 566 567 read_lock_bh(&idev->lock); 568 list_for_each_entry(ifa, &idev->addr_list, if_list) { 569 /* skip tentative addresses until dad completes */ 570 if (ifa->flags & IFA_F_TENTATIVE && 571 !(ifa->flags & IFA_F_OPTIMISTIC)) 572 continue; 573 574 ndisc_send_na(dev, &in6addr_linklocal_allnodes, &ifa->addr, 575 /*router=*/ !!idev->cnf.forwarding, 576 /*solicited=*/ false, /*override=*/ true, 577 /*inc_opt=*/ true); 578 } 579 read_unlock_bh(&idev->lock); 580 581 in6_dev_put(idev); 582 } 583 584 void ndisc_send_ns(struct net_device *dev, const struct in6_addr *solicit, 585 const struct in6_addr *daddr, const struct in6_addr *saddr, 586 u64 nonce) 587 { 588 struct sk_buff *skb; 589 struct in6_addr addr_buf; 590 int inc_opt = dev->addr_len; 591 int optlen = 0; 592 struct nd_msg *msg; 593 594 if (!saddr) { 595 if (ipv6_get_lladdr(dev, &addr_buf, 596 (IFA_F_TENTATIVE|IFA_F_OPTIMISTIC))) 597 return; 598 saddr = &addr_buf; 599 } 600 601 if (ipv6_addr_any(saddr)) 602 inc_opt = false; 603 if (inc_opt) 604 optlen += ndisc_opt_addr_space(dev, 605 NDISC_NEIGHBOUR_SOLICITATION); 606 if (nonce != 0) 607 optlen += 8; 608 609 skb = ndisc_alloc_skb(dev, sizeof(*msg) + optlen); 610 if (!skb) 611 return; 612 613 msg = skb_put(skb, sizeof(*msg)); 614 *msg = (struct nd_msg) { 615 .icmph = { 616 .icmp6_type = NDISC_NEIGHBOUR_SOLICITATION, 617 }, 618 .target = *solicit, 619 }; 620 621 if (inc_opt) 622 ndisc_fill_addr_option(skb, ND_OPT_SOURCE_LL_ADDR, 623 dev->dev_addr, 624 NDISC_NEIGHBOUR_SOLICITATION); 625 if (nonce != 0) { 626 u8 *opt = skb_put(skb, 8); 627 628 opt[0] = ND_OPT_NONCE; 629 opt[1] = 8 >> 3; 630 memcpy(opt + 2, &nonce, 6); 631 } 632 633 ndisc_send_skb(skb, daddr, saddr); 634 } 635 636 void ndisc_send_rs(struct net_device *dev, const struct in6_addr *saddr, 637 const struct in6_addr *daddr) 638 { 639 struct sk_buff *skb; 640 struct rs_msg *msg; 641 int send_sllao = dev->addr_len; 642 int optlen = 0; 643 644 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD 645 /* 646 * According to section 2.2 of RFC 4429, we must not 647 * send router solicitations with a sllao from 648 * optimistic addresses, but we may send the solicitation 649 * if we don't include the sllao. So here we check 650 * if our address is optimistic, and if so, we 651 * suppress the inclusion of the sllao. 652 */ 653 if (send_sllao) { 654 struct inet6_ifaddr *ifp = ipv6_get_ifaddr(dev_net(dev), saddr, 655 dev, 1); 656 if (ifp) { 657 if (ifp->flags & IFA_F_OPTIMISTIC) { 658 send_sllao = 0; 659 } 660 in6_ifa_put(ifp); 661 } else { 662 send_sllao = 0; 663 } 664 } 665 #endif 666 if (send_sllao) 667 optlen += ndisc_opt_addr_space(dev, NDISC_ROUTER_SOLICITATION); 668 669 skb = ndisc_alloc_skb(dev, sizeof(*msg) + optlen); 670 if (!skb) 671 return; 672 673 msg = skb_put(skb, sizeof(*msg)); 674 *msg = (struct rs_msg) { 675 .icmph = { 676 .icmp6_type = NDISC_ROUTER_SOLICITATION, 677 }, 678 }; 679 680 if (send_sllao) 681 ndisc_fill_addr_option(skb, ND_OPT_SOURCE_LL_ADDR, 682 dev->dev_addr, 683 NDISC_ROUTER_SOLICITATION); 684 685 ndisc_send_skb(skb, daddr, saddr); 686 } 687 688 689 static void ndisc_error_report(struct neighbour *neigh, struct sk_buff *skb) 690 { 691 /* 692 * "The sender MUST return an ICMP 693 * destination unreachable" 694 */ 695 dst_link_failure(skb); 696 kfree_skb(skb); 697 } 698 699 /* Called with locked neigh: either read or both */ 700 701 static void ndisc_solicit(struct neighbour *neigh, struct sk_buff *skb) 702 { 703 struct in6_addr *saddr = NULL; 704 struct in6_addr mcaddr; 705 struct net_device *dev = neigh->dev; 706 struct in6_addr *target = (struct in6_addr *)&neigh->primary_key; 707 int probes = atomic_read(&neigh->probes); 708 709 if (skb && ipv6_chk_addr_and_flags(dev_net(dev), &ipv6_hdr(skb)->saddr, 710 dev, false, 1, 711 IFA_F_TENTATIVE|IFA_F_OPTIMISTIC)) 712 saddr = &ipv6_hdr(skb)->saddr; 713 probes -= NEIGH_VAR(neigh->parms, UCAST_PROBES); 714 if (probes < 0) { 715 if (!(neigh->nud_state & NUD_VALID)) { 716 ND_PRINTK(1, dbg, 717 "%s: trying to ucast probe in NUD_INVALID: %pI6\n", 718 __func__, target); 719 } 720 ndisc_send_ns(dev, target, target, saddr, 0); 721 } else if ((probes -= NEIGH_VAR(neigh->parms, APP_PROBES)) < 0) { 722 neigh_app_ns(neigh); 723 } else { 724 addrconf_addr_solict_mult(target, &mcaddr); 725 ndisc_send_ns(dev, target, &mcaddr, saddr, 0); 726 } 727 } 728 729 static int pndisc_is_router(const void *pkey, 730 struct net_device *dev) 731 { 732 struct pneigh_entry *n; 733 int ret = -1; 734 735 read_lock_bh(&nd_tbl.lock); 736 n = __pneigh_lookup(&nd_tbl, dev_net(dev), pkey, dev); 737 if (n) 738 ret = !!(n->flags & NTF_ROUTER); 739 read_unlock_bh(&nd_tbl.lock); 740 741 return ret; 742 } 743 744 void ndisc_update(const struct net_device *dev, struct neighbour *neigh, 745 const u8 *lladdr, u8 new, u32 flags, u8 icmp6_type, 746 struct ndisc_options *ndopts) 747 { 748 neigh_update(neigh, lladdr, new, flags, 0); 749 /* report ndisc ops about neighbour update */ 750 ndisc_ops_update(dev, neigh, flags, icmp6_type, ndopts); 751 } 752 753 static void ndisc_recv_ns(struct sk_buff *skb) 754 { 755 struct nd_msg *msg = (struct nd_msg *)skb_transport_header(skb); 756 const struct in6_addr *saddr = &ipv6_hdr(skb)->saddr; 757 const struct in6_addr *daddr = &ipv6_hdr(skb)->daddr; 758 u8 *lladdr = NULL; 759 u32 ndoptlen = skb_tail_pointer(skb) - (skb_transport_header(skb) + 760 offsetof(struct nd_msg, opt)); 761 struct ndisc_options ndopts; 762 struct net_device *dev = skb->dev; 763 struct inet6_ifaddr *ifp; 764 struct inet6_dev *idev = NULL; 765 struct neighbour *neigh; 766 int dad = ipv6_addr_any(saddr); 767 bool inc; 768 int is_router = -1; 769 u64 nonce = 0; 770 771 if (skb->len < sizeof(struct nd_msg)) { 772 ND_PRINTK(2, warn, "NS: packet too short\n"); 773 return; 774 } 775 776 if (ipv6_addr_is_multicast(&msg->target)) { 777 ND_PRINTK(2, warn, "NS: multicast target address\n"); 778 return; 779 } 780 781 /* 782 * RFC2461 7.1.1: 783 * DAD has to be destined for solicited node multicast address. 784 */ 785 if (dad && !ipv6_addr_is_solict_mult(daddr)) { 786 ND_PRINTK(2, warn, "NS: bad DAD packet (wrong destination)\n"); 787 return; 788 } 789 790 if (!ndisc_parse_options(dev, msg->opt, ndoptlen, &ndopts)) { 791 ND_PRINTK(2, warn, "NS: invalid ND options\n"); 792 return; 793 } 794 795 if (ndopts.nd_opts_src_lladdr) { 796 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr, dev); 797 if (!lladdr) { 798 ND_PRINTK(2, warn, 799 "NS: invalid link-layer address length\n"); 800 return; 801 } 802 803 /* RFC2461 7.1.1: 804 * If the IP source address is the unspecified address, 805 * there MUST NOT be source link-layer address option 806 * in the message. 807 */ 808 if (dad) { 809 ND_PRINTK(2, warn, 810 "NS: bad DAD packet (link-layer address option)\n"); 811 return; 812 } 813 } 814 if (ndopts.nd_opts_nonce) 815 memcpy(&nonce, (u8 *)(ndopts.nd_opts_nonce + 1), 6); 816 817 inc = ipv6_addr_is_multicast(daddr); 818 819 ifp = ipv6_get_ifaddr(dev_net(dev), &msg->target, dev, 1); 820 if (ifp) { 821 have_ifp: 822 if (ifp->flags & (IFA_F_TENTATIVE|IFA_F_OPTIMISTIC)) { 823 if (dad) { 824 if (nonce != 0 && ifp->dad_nonce == nonce) { 825 u8 *np = (u8 *)&nonce; 826 /* Matching nonce if looped back */ 827 ND_PRINTK(2, notice, 828 "%s: IPv6 DAD loopback for address %pI6c nonce %pM ignored\n", 829 ifp->idev->dev->name, 830 &ifp->addr, np); 831 goto out; 832 } 833 /* 834 * We are colliding with another node 835 * who is doing DAD 836 * so fail our DAD process 837 */ 838 addrconf_dad_failure(skb, ifp); 839 return; 840 } else { 841 /* 842 * This is not a dad solicitation. 843 * If we are an optimistic node, 844 * we should respond. 845 * Otherwise, we should ignore it. 846 */ 847 if (!(ifp->flags & IFA_F_OPTIMISTIC)) 848 goto out; 849 } 850 } 851 852 idev = ifp->idev; 853 } else { 854 struct net *net = dev_net(dev); 855 856 /* perhaps an address on the master device */ 857 if (netif_is_l3_slave(dev)) { 858 struct net_device *mdev; 859 860 mdev = netdev_master_upper_dev_get_rcu(dev); 861 if (mdev) { 862 ifp = ipv6_get_ifaddr(net, &msg->target, mdev, 1); 863 if (ifp) 864 goto have_ifp; 865 } 866 } 867 868 idev = in6_dev_get(dev); 869 if (!idev) { 870 /* XXX: count this drop? */ 871 return; 872 } 873 874 if (ipv6_chk_acast_addr(net, dev, &msg->target) || 875 (idev->cnf.forwarding && 876 (net->ipv6.devconf_all->proxy_ndp || idev->cnf.proxy_ndp) && 877 (is_router = pndisc_is_router(&msg->target, dev)) >= 0)) { 878 if (!(NEIGH_CB(skb)->flags & LOCALLY_ENQUEUED) && 879 skb->pkt_type != PACKET_HOST && 880 inc && 881 NEIGH_VAR(idev->nd_parms, PROXY_DELAY) != 0) { 882 /* 883 * for anycast or proxy, 884 * sender should delay its response 885 * by a random time between 0 and 886 * MAX_ANYCAST_DELAY_TIME seconds. 887 * (RFC2461) -- yoshfuji 888 */ 889 struct sk_buff *n = skb_clone(skb, GFP_ATOMIC); 890 if (n) 891 pneigh_enqueue(&nd_tbl, idev->nd_parms, n); 892 goto out; 893 } 894 } else 895 goto out; 896 } 897 898 if (is_router < 0) 899 is_router = idev->cnf.forwarding; 900 901 if (dad) { 902 ndisc_send_na(dev, &in6addr_linklocal_allnodes, &msg->target, 903 !!is_router, false, (ifp != NULL), true); 904 goto out; 905 } 906 907 if (inc) 908 NEIGH_CACHE_STAT_INC(&nd_tbl, rcv_probes_mcast); 909 else 910 NEIGH_CACHE_STAT_INC(&nd_tbl, rcv_probes_ucast); 911 912 /* 913 * update / create cache entry 914 * for the source address 915 */ 916 neigh = __neigh_lookup(&nd_tbl, saddr, dev, 917 !inc || lladdr || !dev->addr_len); 918 if (neigh) 919 ndisc_update(dev, neigh, lladdr, NUD_STALE, 920 NEIGH_UPDATE_F_WEAK_OVERRIDE| 921 NEIGH_UPDATE_F_OVERRIDE, 922 NDISC_NEIGHBOUR_SOLICITATION, &ndopts); 923 if (neigh || !dev->header_ops) { 924 ndisc_send_na(dev, saddr, &msg->target, !!is_router, 925 true, (ifp != NULL && inc), inc); 926 if (neigh) 927 neigh_release(neigh); 928 } 929 930 out: 931 if (ifp) 932 in6_ifa_put(ifp); 933 else 934 in6_dev_put(idev); 935 } 936 937 static void ndisc_recv_na(struct sk_buff *skb) 938 { 939 struct nd_msg *msg = (struct nd_msg *)skb_transport_header(skb); 940 struct in6_addr *saddr = &ipv6_hdr(skb)->saddr; 941 const struct in6_addr *daddr = &ipv6_hdr(skb)->daddr; 942 u8 *lladdr = NULL; 943 u32 ndoptlen = skb_tail_pointer(skb) - (skb_transport_header(skb) + 944 offsetof(struct nd_msg, opt)); 945 struct ndisc_options ndopts; 946 struct net_device *dev = skb->dev; 947 struct inet6_dev *idev = __in6_dev_get(dev); 948 struct inet6_ifaddr *ifp; 949 struct neighbour *neigh; 950 951 if (skb->len < sizeof(struct nd_msg)) { 952 ND_PRINTK(2, warn, "NA: packet too short\n"); 953 return; 954 } 955 956 if (ipv6_addr_is_multicast(&msg->target)) { 957 ND_PRINTK(2, warn, "NA: target address is multicast\n"); 958 return; 959 } 960 961 if (ipv6_addr_is_multicast(daddr) && 962 msg->icmph.icmp6_solicited) { 963 ND_PRINTK(2, warn, "NA: solicited NA is multicasted\n"); 964 return; 965 } 966 967 /* For some 802.11 wireless deployments (and possibly other networks), 968 * there will be a NA proxy and unsolicitd packets are attacks 969 * and thus should not be accepted. 970 */ 971 if (!msg->icmph.icmp6_solicited && idev && 972 idev->cnf.drop_unsolicited_na) 973 return; 974 975 if (!ndisc_parse_options(dev, msg->opt, ndoptlen, &ndopts)) { 976 ND_PRINTK(2, warn, "NS: invalid ND option\n"); 977 return; 978 } 979 if (ndopts.nd_opts_tgt_lladdr) { 980 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr, dev); 981 if (!lladdr) { 982 ND_PRINTK(2, warn, 983 "NA: invalid link-layer address length\n"); 984 return; 985 } 986 } 987 ifp = ipv6_get_ifaddr(dev_net(dev), &msg->target, dev, 1); 988 if (ifp) { 989 if (skb->pkt_type != PACKET_LOOPBACK 990 && (ifp->flags & IFA_F_TENTATIVE)) { 991 addrconf_dad_failure(skb, ifp); 992 return; 993 } 994 /* What should we make now? The advertisement 995 is invalid, but ndisc specs say nothing 996 about it. It could be misconfiguration, or 997 an smart proxy agent tries to help us :-) 998 999 We should not print the error if NA has been 1000 received from loopback - it is just our own 1001 unsolicited advertisement. 1002 */ 1003 if (skb->pkt_type != PACKET_LOOPBACK) 1004 ND_PRINTK(1, warn, 1005 "NA: %pM advertised our address %pI6c on %s!\n", 1006 eth_hdr(skb)->h_source, &ifp->addr, ifp->idev->dev->name); 1007 in6_ifa_put(ifp); 1008 return; 1009 } 1010 neigh = neigh_lookup(&nd_tbl, &msg->target, dev); 1011 1012 if (neigh) { 1013 u8 old_flags = neigh->flags; 1014 struct net *net = dev_net(dev); 1015 1016 if (neigh->nud_state & NUD_FAILED) 1017 goto out; 1018 1019 /* 1020 * Don't update the neighbor cache entry on a proxy NA from 1021 * ourselves because either the proxied node is off link or it 1022 * has already sent a NA to us. 1023 */ 1024 if (lladdr && !memcmp(lladdr, dev->dev_addr, dev->addr_len) && 1025 net->ipv6.devconf_all->forwarding && net->ipv6.devconf_all->proxy_ndp && 1026 pneigh_lookup(&nd_tbl, net, &msg->target, dev, 0)) { 1027 /* XXX: idev->cnf.proxy_ndp */ 1028 goto out; 1029 } 1030 1031 ndisc_update(dev, neigh, lladdr, 1032 msg->icmph.icmp6_solicited ? NUD_REACHABLE : NUD_STALE, 1033 NEIGH_UPDATE_F_WEAK_OVERRIDE| 1034 (msg->icmph.icmp6_override ? NEIGH_UPDATE_F_OVERRIDE : 0)| 1035 NEIGH_UPDATE_F_OVERRIDE_ISROUTER| 1036 (msg->icmph.icmp6_router ? NEIGH_UPDATE_F_ISROUTER : 0), 1037 NDISC_NEIGHBOUR_ADVERTISEMENT, &ndopts); 1038 1039 if ((old_flags & ~neigh->flags) & NTF_ROUTER) { 1040 /* 1041 * Change: router to host 1042 */ 1043 rt6_clean_tohost(dev_net(dev), saddr); 1044 } 1045 1046 out: 1047 neigh_release(neigh); 1048 } 1049 } 1050 1051 static void ndisc_recv_rs(struct sk_buff *skb) 1052 { 1053 struct rs_msg *rs_msg = (struct rs_msg *)skb_transport_header(skb); 1054 unsigned long ndoptlen = skb->len - sizeof(*rs_msg); 1055 struct neighbour *neigh; 1056 struct inet6_dev *idev; 1057 const struct in6_addr *saddr = &ipv6_hdr(skb)->saddr; 1058 struct ndisc_options ndopts; 1059 u8 *lladdr = NULL; 1060 1061 if (skb->len < sizeof(*rs_msg)) 1062 return; 1063 1064 idev = __in6_dev_get(skb->dev); 1065 if (!idev) { 1066 ND_PRINTK(1, err, "RS: can't find in6 device\n"); 1067 return; 1068 } 1069 1070 /* Don't accept RS if we're not in router mode */ 1071 if (!idev->cnf.forwarding) 1072 goto out; 1073 1074 /* 1075 * Don't update NCE if src = ::; 1076 * this implies that the source node has no ip address assigned yet. 1077 */ 1078 if (ipv6_addr_any(saddr)) 1079 goto out; 1080 1081 /* Parse ND options */ 1082 if (!ndisc_parse_options(skb->dev, rs_msg->opt, ndoptlen, &ndopts)) { 1083 ND_PRINTK(2, notice, "NS: invalid ND option, ignored\n"); 1084 goto out; 1085 } 1086 1087 if (ndopts.nd_opts_src_lladdr) { 1088 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr, 1089 skb->dev); 1090 if (!lladdr) 1091 goto out; 1092 } 1093 1094 neigh = __neigh_lookup(&nd_tbl, saddr, skb->dev, 1); 1095 if (neigh) { 1096 ndisc_update(skb->dev, neigh, lladdr, NUD_STALE, 1097 NEIGH_UPDATE_F_WEAK_OVERRIDE| 1098 NEIGH_UPDATE_F_OVERRIDE| 1099 NEIGH_UPDATE_F_OVERRIDE_ISROUTER, 1100 NDISC_ROUTER_SOLICITATION, &ndopts); 1101 neigh_release(neigh); 1102 } 1103 out: 1104 return; 1105 } 1106 1107 static void ndisc_ra_useropt(struct sk_buff *ra, struct nd_opt_hdr *opt) 1108 { 1109 struct icmp6hdr *icmp6h = (struct icmp6hdr *)skb_transport_header(ra); 1110 struct sk_buff *skb; 1111 struct nlmsghdr *nlh; 1112 struct nduseroptmsg *ndmsg; 1113 struct net *net = dev_net(ra->dev); 1114 int err; 1115 int base_size = NLMSG_ALIGN(sizeof(struct nduseroptmsg) 1116 + (opt->nd_opt_len << 3)); 1117 size_t msg_size = base_size + nla_total_size(sizeof(struct in6_addr)); 1118 1119 skb = nlmsg_new(msg_size, GFP_ATOMIC); 1120 if (!skb) { 1121 err = -ENOBUFS; 1122 goto errout; 1123 } 1124 1125 nlh = nlmsg_put(skb, 0, 0, RTM_NEWNDUSEROPT, base_size, 0); 1126 if (!nlh) { 1127 goto nla_put_failure; 1128 } 1129 1130 ndmsg = nlmsg_data(nlh); 1131 ndmsg->nduseropt_family = AF_INET6; 1132 ndmsg->nduseropt_ifindex = ra->dev->ifindex; 1133 ndmsg->nduseropt_icmp_type = icmp6h->icmp6_type; 1134 ndmsg->nduseropt_icmp_code = icmp6h->icmp6_code; 1135 ndmsg->nduseropt_opts_len = opt->nd_opt_len << 3; 1136 1137 memcpy(ndmsg + 1, opt, opt->nd_opt_len << 3); 1138 1139 if (nla_put_in6_addr(skb, NDUSEROPT_SRCADDR, &ipv6_hdr(ra)->saddr)) 1140 goto nla_put_failure; 1141 nlmsg_end(skb, nlh); 1142 1143 rtnl_notify(skb, net, 0, RTNLGRP_ND_USEROPT, NULL, GFP_ATOMIC); 1144 return; 1145 1146 nla_put_failure: 1147 nlmsg_free(skb); 1148 err = -EMSGSIZE; 1149 errout: 1150 rtnl_set_sk_err(net, RTNLGRP_ND_USEROPT, err); 1151 } 1152 1153 static void ndisc_router_discovery(struct sk_buff *skb) 1154 { 1155 struct ra_msg *ra_msg = (struct ra_msg *)skb_transport_header(skb); 1156 struct neighbour *neigh = NULL; 1157 struct inet6_dev *in6_dev; 1158 struct rt6_info *rt = NULL; 1159 int lifetime; 1160 struct ndisc_options ndopts; 1161 int optlen; 1162 unsigned int pref = 0; 1163 __u32 old_if_flags; 1164 bool send_ifinfo_notify = false; 1165 1166 __u8 *opt = (__u8 *)(ra_msg + 1); 1167 1168 optlen = (skb_tail_pointer(skb) - skb_transport_header(skb)) - 1169 sizeof(struct ra_msg); 1170 1171 ND_PRINTK(2, info, 1172 "RA: %s, dev: %s\n", 1173 __func__, skb->dev->name); 1174 if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) { 1175 ND_PRINTK(2, warn, "RA: source address is not link-local\n"); 1176 return; 1177 } 1178 if (optlen < 0) { 1179 ND_PRINTK(2, warn, "RA: packet too short\n"); 1180 return; 1181 } 1182 1183 #ifdef CONFIG_IPV6_NDISC_NODETYPE 1184 if (skb->ndisc_nodetype == NDISC_NODETYPE_HOST) { 1185 ND_PRINTK(2, warn, "RA: from host or unauthorized router\n"); 1186 return; 1187 } 1188 #endif 1189 1190 /* 1191 * set the RA_RECV flag in the interface 1192 */ 1193 1194 in6_dev = __in6_dev_get(skb->dev); 1195 if (!in6_dev) { 1196 ND_PRINTK(0, err, "RA: can't find inet6 device for %s\n", 1197 skb->dev->name); 1198 return; 1199 } 1200 1201 if (!ndisc_parse_options(skb->dev, opt, optlen, &ndopts)) { 1202 ND_PRINTK(2, warn, "RA: invalid ND options\n"); 1203 return; 1204 } 1205 1206 if (!ipv6_accept_ra(in6_dev)) { 1207 ND_PRINTK(2, info, 1208 "RA: %s, did not accept ra for dev: %s\n", 1209 __func__, skb->dev->name); 1210 goto skip_linkparms; 1211 } 1212 1213 #ifdef CONFIG_IPV6_NDISC_NODETYPE 1214 /* skip link-specific parameters from interior routers */ 1215 if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT) { 1216 ND_PRINTK(2, info, 1217 "RA: %s, nodetype is NODEFAULT, dev: %s\n", 1218 __func__, skb->dev->name); 1219 goto skip_linkparms; 1220 } 1221 #endif 1222 1223 if (in6_dev->if_flags & IF_RS_SENT) { 1224 /* 1225 * flag that an RA was received after an RS was sent 1226 * out on this interface. 1227 */ 1228 in6_dev->if_flags |= IF_RA_RCVD; 1229 } 1230 1231 /* 1232 * Remember the managed/otherconf flags from most recently 1233 * received RA message (RFC 2462) -- yoshfuji 1234 */ 1235 old_if_flags = in6_dev->if_flags; 1236 in6_dev->if_flags = (in6_dev->if_flags & ~(IF_RA_MANAGED | 1237 IF_RA_OTHERCONF)) | 1238 (ra_msg->icmph.icmp6_addrconf_managed ? 1239 IF_RA_MANAGED : 0) | 1240 (ra_msg->icmph.icmp6_addrconf_other ? 1241 IF_RA_OTHERCONF : 0); 1242 1243 if (old_if_flags != in6_dev->if_flags) 1244 send_ifinfo_notify = true; 1245 1246 if (!in6_dev->cnf.accept_ra_defrtr) { 1247 ND_PRINTK(2, info, 1248 "RA: %s, defrtr is false for dev: %s\n", 1249 __func__, skb->dev->name); 1250 goto skip_defrtr; 1251 } 1252 1253 /* Do not accept RA with source-addr found on local machine unless 1254 * accept_ra_from_local is set to true. 1255 */ 1256 if (!in6_dev->cnf.accept_ra_from_local && 1257 ipv6_chk_addr(dev_net(in6_dev->dev), &ipv6_hdr(skb)->saddr, 1258 in6_dev->dev, 0)) { 1259 ND_PRINTK(2, info, 1260 "RA from local address detected on dev: %s: default router ignored\n", 1261 skb->dev->name); 1262 goto skip_defrtr; 1263 } 1264 1265 lifetime = ntohs(ra_msg->icmph.icmp6_rt_lifetime); 1266 1267 #ifdef CONFIG_IPV6_ROUTER_PREF 1268 pref = ra_msg->icmph.icmp6_router_pref; 1269 /* 10b is handled as if it were 00b (medium) */ 1270 if (pref == ICMPV6_ROUTER_PREF_INVALID || 1271 !in6_dev->cnf.accept_ra_rtr_pref) 1272 pref = ICMPV6_ROUTER_PREF_MEDIUM; 1273 #endif 1274 1275 rt = rt6_get_dflt_router(&ipv6_hdr(skb)->saddr, skb->dev); 1276 1277 if (rt) { 1278 neigh = dst_neigh_lookup(&rt->dst, &ipv6_hdr(skb)->saddr); 1279 if (!neigh) { 1280 ND_PRINTK(0, err, 1281 "RA: %s got default router without neighbour\n", 1282 __func__); 1283 ip6_rt_put(rt); 1284 return; 1285 } 1286 } 1287 if (rt && lifetime == 0) { 1288 ip6_del_rt(rt); 1289 rt = NULL; 1290 } 1291 1292 ND_PRINTK(3, info, "RA: rt: %p lifetime: %d, for dev: %s\n", 1293 rt, lifetime, skb->dev->name); 1294 if (!rt && lifetime) { 1295 ND_PRINTK(3, info, "RA: adding default router\n"); 1296 1297 rt = rt6_add_dflt_router(&ipv6_hdr(skb)->saddr, skb->dev, pref); 1298 if (!rt) { 1299 ND_PRINTK(0, err, 1300 "RA: %s failed to add default route\n", 1301 __func__); 1302 return; 1303 } 1304 1305 neigh = dst_neigh_lookup(&rt->dst, &ipv6_hdr(skb)->saddr); 1306 if (!neigh) { 1307 ND_PRINTK(0, err, 1308 "RA: %s got default router without neighbour\n", 1309 __func__); 1310 ip6_rt_put(rt); 1311 return; 1312 } 1313 neigh->flags |= NTF_ROUTER; 1314 } else if (rt) { 1315 rt->rt6i_flags = (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref); 1316 } 1317 1318 if (rt) 1319 rt6_set_expires(rt, jiffies + (HZ * lifetime)); 1320 if (in6_dev->cnf.accept_ra_min_hop_limit < 256 && 1321 ra_msg->icmph.icmp6_hop_limit) { 1322 if (in6_dev->cnf.accept_ra_min_hop_limit <= ra_msg->icmph.icmp6_hop_limit) { 1323 in6_dev->cnf.hop_limit = ra_msg->icmph.icmp6_hop_limit; 1324 if (rt) 1325 dst_metric_set(&rt->dst, RTAX_HOPLIMIT, 1326 ra_msg->icmph.icmp6_hop_limit); 1327 } else { 1328 ND_PRINTK(2, warn, "RA: Got route advertisement with lower hop_limit than minimum\n"); 1329 } 1330 } 1331 1332 skip_defrtr: 1333 1334 /* 1335 * Update Reachable Time and Retrans Timer 1336 */ 1337 1338 if (in6_dev->nd_parms) { 1339 unsigned long rtime = ntohl(ra_msg->retrans_timer); 1340 1341 if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/HZ) { 1342 rtime = (rtime*HZ)/1000; 1343 if (rtime < HZ/10) 1344 rtime = HZ/10; 1345 NEIGH_VAR_SET(in6_dev->nd_parms, RETRANS_TIME, rtime); 1346 in6_dev->tstamp = jiffies; 1347 send_ifinfo_notify = true; 1348 } 1349 1350 rtime = ntohl(ra_msg->reachable_time); 1351 if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/(3*HZ)) { 1352 rtime = (rtime*HZ)/1000; 1353 1354 if (rtime < HZ/10) 1355 rtime = HZ/10; 1356 1357 if (rtime != NEIGH_VAR(in6_dev->nd_parms, BASE_REACHABLE_TIME)) { 1358 NEIGH_VAR_SET(in6_dev->nd_parms, 1359 BASE_REACHABLE_TIME, rtime); 1360 NEIGH_VAR_SET(in6_dev->nd_parms, 1361 GC_STALETIME, 3 * rtime); 1362 in6_dev->nd_parms->reachable_time = neigh_rand_reach_time(rtime); 1363 in6_dev->tstamp = jiffies; 1364 send_ifinfo_notify = true; 1365 } 1366 } 1367 } 1368 1369 /* 1370 * Send a notify if RA changed managed/otherconf flags or timer settings 1371 */ 1372 if (send_ifinfo_notify) 1373 inet6_ifinfo_notify(RTM_NEWLINK, in6_dev); 1374 1375 skip_linkparms: 1376 1377 /* 1378 * Process options. 1379 */ 1380 1381 if (!neigh) 1382 neigh = __neigh_lookup(&nd_tbl, &ipv6_hdr(skb)->saddr, 1383 skb->dev, 1); 1384 if (neigh) { 1385 u8 *lladdr = NULL; 1386 if (ndopts.nd_opts_src_lladdr) { 1387 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr, 1388 skb->dev); 1389 if (!lladdr) { 1390 ND_PRINTK(2, warn, 1391 "RA: invalid link-layer address length\n"); 1392 goto out; 1393 } 1394 } 1395 ndisc_update(skb->dev, neigh, lladdr, NUD_STALE, 1396 NEIGH_UPDATE_F_WEAK_OVERRIDE| 1397 NEIGH_UPDATE_F_OVERRIDE| 1398 NEIGH_UPDATE_F_OVERRIDE_ISROUTER| 1399 NEIGH_UPDATE_F_ISROUTER, 1400 NDISC_ROUTER_ADVERTISEMENT, &ndopts); 1401 } 1402 1403 if (!ipv6_accept_ra(in6_dev)) { 1404 ND_PRINTK(2, info, 1405 "RA: %s, accept_ra is false for dev: %s\n", 1406 __func__, skb->dev->name); 1407 goto out; 1408 } 1409 1410 #ifdef CONFIG_IPV6_ROUTE_INFO 1411 if (!in6_dev->cnf.accept_ra_from_local && 1412 ipv6_chk_addr(dev_net(in6_dev->dev), &ipv6_hdr(skb)->saddr, 1413 in6_dev->dev, 0)) { 1414 ND_PRINTK(2, info, 1415 "RA from local address detected on dev: %s: router info ignored.\n", 1416 skb->dev->name); 1417 goto skip_routeinfo; 1418 } 1419 1420 if (in6_dev->cnf.accept_ra_rtr_pref && ndopts.nd_opts_ri) { 1421 struct nd_opt_hdr *p; 1422 for (p = ndopts.nd_opts_ri; 1423 p; 1424 p = ndisc_next_option(p, ndopts.nd_opts_ri_end)) { 1425 struct route_info *ri = (struct route_info *)p; 1426 #ifdef CONFIG_IPV6_NDISC_NODETYPE 1427 if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT && 1428 ri->prefix_len == 0) 1429 continue; 1430 #endif 1431 if (ri->prefix_len == 0 && 1432 !in6_dev->cnf.accept_ra_defrtr) 1433 continue; 1434 if (ri->prefix_len < in6_dev->cnf.accept_ra_rt_info_min_plen) 1435 continue; 1436 if (ri->prefix_len > in6_dev->cnf.accept_ra_rt_info_max_plen) 1437 continue; 1438 rt6_route_rcv(skb->dev, (u8 *)p, (p->nd_opt_len) << 3, 1439 &ipv6_hdr(skb)->saddr); 1440 } 1441 } 1442 1443 skip_routeinfo: 1444 #endif 1445 1446 #ifdef CONFIG_IPV6_NDISC_NODETYPE 1447 /* skip link-specific ndopts from interior routers */ 1448 if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT) { 1449 ND_PRINTK(2, info, 1450 "RA: %s, nodetype is NODEFAULT (interior routes), dev: %s\n", 1451 __func__, skb->dev->name); 1452 goto out; 1453 } 1454 #endif 1455 1456 if (in6_dev->cnf.accept_ra_pinfo && ndopts.nd_opts_pi) { 1457 struct nd_opt_hdr *p; 1458 for (p = ndopts.nd_opts_pi; 1459 p; 1460 p = ndisc_next_option(p, ndopts.nd_opts_pi_end)) { 1461 addrconf_prefix_rcv(skb->dev, (u8 *)p, 1462 (p->nd_opt_len) << 3, 1463 ndopts.nd_opts_src_lladdr != NULL); 1464 } 1465 } 1466 1467 if (ndopts.nd_opts_mtu && in6_dev->cnf.accept_ra_mtu) { 1468 __be32 n; 1469 u32 mtu; 1470 1471 memcpy(&n, ((u8 *)(ndopts.nd_opts_mtu+1))+2, sizeof(mtu)); 1472 mtu = ntohl(n); 1473 1474 if (mtu < IPV6_MIN_MTU || mtu > skb->dev->mtu) { 1475 ND_PRINTK(2, warn, "RA: invalid mtu: %d\n", mtu); 1476 } else if (in6_dev->cnf.mtu6 != mtu) { 1477 in6_dev->cnf.mtu6 = mtu; 1478 1479 if (rt) 1480 dst_metric_set(&rt->dst, RTAX_MTU, mtu); 1481 1482 rt6_mtu_change(skb->dev, mtu); 1483 } 1484 } 1485 1486 if (ndopts.nd_useropts) { 1487 struct nd_opt_hdr *p; 1488 for (p = ndopts.nd_useropts; 1489 p; 1490 p = ndisc_next_useropt(skb->dev, p, 1491 ndopts.nd_useropts_end)) { 1492 ndisc_ra_useropt(skb, p); 1493 } 1494 } 1495 1496 if (ndopts.nd_opts_tgt_lladdr || ndopts.nd_opts_rh) { 1497 ND_PRINTK(2, warn, "RA: invalid RA options\n"); 1498 } 1499 out: 1500 ip6_rt_put(rt); 1501 if (neigh) 1502 neigh_release(neigh); 1503 } 1504 1505 static void ndisc_redirect_rcv(struct sk_buff *skb) 1506 { 1507 u8 *hdr; 1508 struct ndisc_options ndopts; 1509 struct rd_msg *msg = (struct rd_msg *)skb_transport_header(skb); 1510 u32 ndoptlen = skb_tail_pointer(skb) - (skb_transport_header(skb) + 1511 offsetof(struct rd_msg, opt)); 1512 1513 #ifdef CONFIG_IPV6_NDISC_NODETYPE 1514 switch (skb->ndisc_nodetype) { 1515 case NDISC_NODETYPE_HOST: 1516 case NDISC_NODETYPE_NODEFAULT: 1517 ND_PRINTK(2, warn, 1518 "Redirect: from host or unauthorized router\n"); 1519 return; 1520 } 1521 #endif 1522 1523 if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) { 1524 ND_PRINTK(2, warn, 1525 "Redirect: source address is not link-local\n"); 1526 return; 1527 } 1528 1529 if (!ndisc_parse_options(skb->dev, msg->opt, ndoptlen, &ndopts)) 1530 return; 1531 1532 if (!ndopts.nd_opts_rh) { 1533 ip6_redirect_no_header(skb, dev_net(skb->dev), 1534 skb->dev->ifindex, 0); 1535 return; 1536 } 1537 1538 hdr = (u8 *)ndopts.nd_opts_rh; 1539 hdr += 8; 1540 if (!pskb_pull(skb, hdr - skb_transport_header(skb))) 1541 return; 1542 1543 icmpv6_notify(skb, NDISC_REDIRECT, 0, 0); 1544 } 1545 1546 static void ndisc_fill_redirect_hdr_option(struct sk_buff *skb, 1547 struct sk_buff *orig_skb, 1548 int rd_len) 1549 { 1550 u8 *opt = skb_put(skb, rd_len); 1551 1552 memset(opt, 0, 8); 1553 *(opt++) = ND_OPT_REDIRECT_HDR; 1554 *(opt++) = (rd_len >> 3); 1555 opt += 6; 1556 1557 skb_copy_bits(orig_skb, skb_network_offset(orig_skb), opt, 1558 rd_len - 8); 1559 } 1560 1561 void ndisc_send_redirect(struct sk_buff *skb, const struct in6_addr *target) 1562 { 1563 struct net_device *dev = skb->dev; 1564 struct net *net = dev_net(dev); 1565 struct sock *sk = net->ipv6.ndisc_sk; 1566 int optlen = 0; 1567 struct inet_peer *peer; 1568 struct sk_buff *buff; 1569 struct rd_msg *msg; 1570 struct in6_addr saddr_buf; 1571 struct rt6_info *rt; 1572 struct dst_entry *dst; 1573 struct flowi6 fl6; 1574 int rd_len; 1575 u8 ha_buf[MAX_ADDR_LEN], *ha = NULL, 1576 ops_data_buf[NDISC_OPS_REDIRECT_DATA_SPACE], *ops_data = NULL; 1577 bool ret; 1578 1579 if (ipv6_get_lladdr(dev, &saddr_buf, IFA_F_TENTATIVE)) { 1580 ND_PRINTK(2, warn, "Redirect: no link-local address on %s\n", 1581 dev->name); 1582 return; 1583 } 1584 1585 if (!ipv6_addr_equal(&ipv6_hdr(skb)->daddr, target) && 1586 ipv6_addr_type(target) != (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) { 1587 ND_PRINTK(2, warn, 1588 "Redirect: target address is not link-local unicast\n"); 1589 return; 1590 } 1591 1592 icmpv6_flow_init(sk, &fl6, NDISC_REDIRECT, 1593 &saddr_buf, &ipv6_hdr(skb)->saddr, dev->ifindex); 1594 1595 dst = ip6_route_output(net, NULL, &fl6); 1596 if (dst->error) { 1597 dst_release(dst); 1598 return; 1599 } 1600 dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), NULL, 0); 1601 if (IS_ERR(dst)) 1602 return; 1603 1604 rt = (struct rt6_info *) dst; 1605 1606 if (rt->rt6i_flags & RTF_GATEWAY) { 1607 ND_PRINTK(2, warn, 1608 "Redirect: destination is not a neighbour\n"); 1609 goto release; 1610 } 1611 peer = inet_getpeer_v6(net->ipv6.peers, &ipv6_hdr(skb)->saddr, 1); 1612 ret = inet_peer_xrlim_allow(peer, 1*HZ); 1613 if (peer) 1614 inet_putpeer(peer); 1615 if (!ret) 1616 goto release; 1617 1618 if (dev->addr_len) { 1619 struct neighbour *neigh = dst_neigh_lookup(skb_dst(skb), target); 1620 if (!neigh) { 1621 ND_PRINTK(2, warn, 1622 "Redirect: no neigh for target address\n"); 1623 goto release; 1624 } 1625 1626 read_lock_bh(&neigh->lock); 1627 if (neigh->nud_state & NUD_VALID) { 1628 memcpy(ha_buf, neigh->ha, dev->addr_len); 1629 read_unlock_bh(&neigh->lock); 1630 ha = ha_buf; 1631 optlen += ndisc_redirect_opt_addr_space(dev, neigh, 1632 ops_data_buf, 1633 &ops_data); 1634 } else 1635 read_unlock_bh(&neigh->lock); 1636 1637 neigh_release(neigh); 1638 } 1639 1640 rd_len = min_t(unsigned int, 1641 IPV6_MIN_MTU - sizeof(struct ipv6hdr) - sizeof(*msg) - optlen, 1642 skb->len + 8); 1643 rd_len &= ~0x7; 1644 optlen += rd_len; 1645 1646 buff = ndisc_alloc_skb(dev, sizeof(*msg) + optlen); 1647 if (!buff) 1648 goto release; 1649 1650 msg = skb_put(buff, sizeof(*msg)); 1651 *msg = (struct rd_msg) { 1652 .icmph = { 1653 .icmp6_type = NDISC_REDIRECT, 1654 }, 1655 .target = *target, 1656 .dest = ipv6_hdr(skb)->daddr, 1657 }; 1658 1659 /* 1660 * include target_address option 1661 */ 1662 1663 if (ha) 1664 ndisc_fill_redirect_addr_option(buff, ha, ops_data); 1665 1666 /* 1667 * build redirect option and copy skb over to the new packet. 1668 */ 1669 1670 if (rd_len) 1671 ndisc_fill_redirect_hdr_option(buff, skb, rd_len); 1672 1673 skb_dst_set(buff, dst); 1674 ndisc_send_skb(buff, &ipv6_hdr(skb)->saddr, &saddr_buf); 1675 return; 1676 1677 release: 1678 dst_release(dst); 1679 } 1680 1681 static void pndisc_redo(struct sk_buff *skb) 1682 { 1683 ndisc_recv_ns(skb); 1684 kfree_skb(skb); 1685 } 1686 1687 static bool ndisc_suppress_frag_ndisc(struct sk_buff *skb) 1688 { 1689 struct inet6_dev *idev = __in6_dev_get(skb->dev); 1690 1691 if (!idev) 1692 return true; 1693 if (IP6CB(skb)->flags & IP6SKB_FRAGMENTED && 1694 idev->cnf.suppress_frag_ndisc) { 1695 net_warn_ratelimited("Received fragmented ndisc packet. Carefully consider disabling suppress_frag_ndisc.\n"); 1696 return true; 1697 } 1698 return false; 1699 } 1700 1701 int ndisc_rcv(struct sk_buff *skb) 1702 { 1703 struct nd_msg *msg; 1704 1705 if (ndisc_suppress_frag_ndisc(skb)) 1706 return 0; 1707 1708 if (skb_linearize(skb)) 1709 return 0; 1710 1711 msg = (struct nd_msg *)skb_transport_header(skb); 1712 1713 __skb_push(skb, skb->data - skb_transport_header(skb)); 1714 1715 if (ipv6_hdr(skb)->hop_limit != 255) { 1716 ND_PRINTK(2, warn, "NDISC: invalid hop-limit: %d\n", 1717 ipv6_hdr(skb)->hop_limit); 1718 return 0; 1719 } 1720 1721 if (msg->icmph.icmp6_code != 0) { 1722 ND_PRINTK(2, warn, "NDISC: invalid ICMPv6 code: %d\n", 1723 msg->icmph.icmp6_code); 1724 return 0; 1725 } 1726 1727 memset(NEIGH_CB(skb), 0, sizeof(struct neighbour_cb)); 1728 1729 switch (msg->icmph.icmp6_type) { 1730 case NDISC_NEIGHBOUR_SOLICITATION: 1731 ndisc_recv_ns(skb); 1732 break; 1733 1734 case NDISC_NEIGHBOUR_ADVERTISEMENT: 1735 ndisc_recv_na(skb); 1736 break; 1737 1738 case NDISC_ROUTER_SOLICITATION: 1739 ndisc_recv_rs(skb); 1740 break; 1741 1742 case NDISC_ROUTER_ADVERTISEMENT: 1743 ndisc_router_discovery(skb); 1744 break; 1745 1746 case NDISC_REDIRECT: 1747 ndisc_redirect_rcv(skb); 1748 break; 1749 } 1750 1751 return 0; 1752 } 1753 1754 static int ndisc_netdev_event(struct notifier_block *this, unsigned long event, void *ptr) 1755 { 1756 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 1757 struct netdev_notifier_change_info *change_info; 1758 struct net *net = dev_net(dev); 1759 struct inet6_dev *idev; 1760 1761 switch (event) { 1762 case NETDEV_CHANGEADDR: 1763 neigh_changeaddr(&nd_tbl, dev); 1764 fib6_run_gc(0, net, false); 1765 /* fallthrough */ 1766 case NETDEV_UP: 1767 idev = in6_dev_get(dev); 1768 if (!idev) 1769 break; 1770 if (idev->cnf.ndisc_notify || 1771 net->ipv6.devconf_all->ndisc_notify) 1772 ndisc_send_unsol_na(dev); 1773 in6_dev_put(idev); 1774 break; 1775 case NETDEV_CHANGE: 1776 change_info = ptr; 1777 if (change_info->flags_changed & IFF_NOARP) 1778 neigh_changeaddr(&nd_tbl, dev); 1779 break; 1780 case NETDEV_DOWN: 1781 neigh_ifdown(&nd_tbl, dev); 1782 fib6_run_gc(0, net, false); 1783 break; 1784 case NETDEV_NOTIFY_PEERS: 1785 ndisc_send_unsol_na(dev); 1786 break; 1787 default: 1788 break; 1789 } 1790 1791 return NOTIFY_DONE; 1792 } 1793 1794 static struct notifier_block ndisc_netdev_notifier = { 1795 .notifier_call = ndisc_netdev_event, 1796 .priority = ADDRCONF_NOTIFY_PRIORITY - 5, 1797 }; 1798 1799 #ifdef CONFIG_SYSCTL 1800 static void ndisc_warn_deprecated_sysctl(struct ctl_table *ctl, 1801 const char *func, const char *dev_name) 1802 { 1803 static char warncomm[TASK_COMM_LEN]; 1804 static int warned; 1805 if (strcmp(warncomm, current->comm) && warned < 5) { 1806 strcpy(warncomm, current->comm); 1807 pr_warn("process `%s' is using deprecated sysctl (%s) net.ipv6.neigh.%s.%s - use net.ipv6.neigh.%s.%s_ms instead\n", 1808 warncomm, func, 1809 dev_name, ctl->procname, 1810 dev_name, ctl->procname); 1811 warned++; 1812 } 1813 } 1814 1815 int ndisc_ifinfo_sysctl_change(struct ctl_table *ctl, int write, void __user *buffer, size_t *lenp, loff_t *ppos) 1816 { 1817 struct net_device *dev = ctl->extra1; 1818 struct inet6_dev *idev; 1819 int ret; 1820 1821 if ((strcmp(ctl->procname, "retrans_time") == 0) || 1822 (strcmp(ctl->procname, "base_reachable_time") == 0)) 1823 ndisc_warn_deprecated_sysctl(ctl, "syscall", dev ? dev->name : "default"); 1824 1825 if (strcmp(ctl->procname, "retrans_time") == 0) 1826 ret = neigh_proc_dointvec(ctl, write, buffer, lenp, ppos); 1827 1828 else if (strcmp(ctl->procname, "base_reachable_time") == 0) 1829 ret = neigh_proc_dointvec_jiffies(ctl, write, 1830 buffer, lenp, ppos); 1831 1832 else if ((strcmp(ctl->procname, "retrans_time_ms") == 0) || 1833 (strcmp(ctl->procname, "base_reachable_time_ms") == 0)) 1834 ret = neigh_proc_dointvec_ms_jiffies(ctl, write, 1835 buffer, lenp, ppos); 1836 else 1837 ret = -1; 1838 1839 if (write && ret == 0 && dev && (idev = in6_dev_get(dev)) != NULL) { 1840 if (ctl->data == &NEIGH_VAR(idev->nd_parms, BASE_REACHABLE_TIME)) 1841 idev->nd_parms->reachable_time = 1842 neigh_rand_reach_time(NEIGH_VAR(idev->nd_parms, BASE_REACHABLE_TIME)); 1843 idev->tstamp = jiffies; 1844 inet6_ifinfo_notify(RTM_NEWLINK, idev); 1845 in6_dev_put(idev); 1846 } 1847 return ret; 1848 } 1849 1850 1851 #endif 1852 1853 static int __net_init ndisc_net_init(struct net *net) 1854 { 1855 struct ipv6_pinfo *np; 1856 struct sock *sk; 1857 int err; 1858 1859 err = inet_ctl_sock_create(&sk, PF_INET6, 1860 SOCK_RAW, IPPROTO_ICMPV6, net); 1861 if (err < 0) { 1862 ND_PRINTK(0, err, 1863 "NDISC: Failed to initialize the control socket (err %d)\n", 1864 err); 1865 return err; 1866 } 1867 1868 net->ipv6.ndisc_sk = sk; 1869 1870 np = inet6_sk(sk); 1871 np->hop_limit = 255; 1872 /* Do not loopback ndisc messages */ 1873 np->mc_loop = 0; 1874 1875 return 0; 1876 } 1877 1878 static void __net_exit ndisc_net_exit(struct net *net) 1879 { 1880 inet_ctl_sock_destroy(net->ipv6.ndisc_sk); 1881 } 1882 1883 static struct pernet_operations ndisc_net_ops = { 1884 .init = ndisc_net_init, 1885 .exit = ndisc_net_exit, 1886 }; 1887 1888 int __init ndisc_init(void) 1889 { 1890 int err; 1891 1892 err = register_pernet_subsys(&ndisc_net_ops); 1893 if (err) 1894 return err; 1895 /* 1896 * Initialize the neighbour table 1897 */ 1898 neigh_table_init(NEIGH_ND_TABLE, &nd_tbl); 1899 1900 #ifdef CONFIG_SYSCTL 1901 err = neigh_sysctl_register(NULL, &nd_tbl.parms, 1902 ndisc_ifinfo_sysctl_change); 1903 if (err) 1904 goto out_unregister_pernet; 1905 out: 1906 #endif 1907 return err; 1908 1909 #ifdef CONFIG_SYSCTL 1910 out_unregister_pernet: 1911 unregister_pernet_subsys(&ndisc_net_ops); 1912 goto out; 1913 #endif 1914 } 1915 1916 int __init ndisc_late_init(void) 1917 { 1918 return register_netdevice_notifier(&ndisc_netdev_notifier); 1919 } 1920 1921 void ndisc_late_cleanup(void) 1922 { 1923 unregister_netdevice_notifier(&ndisc_netdev_notifier); 1924 } 1925 1926 void ndisc_cleanup(void) 1927 { 1928 #ifdef CONFIG_SYSCTL 1929 neigh_sysctl_unregister(&nd_tbl.parms); 1930 #endif 1931 neigh_table_clear(NEIGH_ND_TABLE, &nd_tbl); 1932 unregister_pernet_subsys(&ndisc_net_ops); 1933 } 1934