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 bool ndisc_allow_add(const struct net_device *dev, 81 struct netlink_ext_ack *extack); 82 static int ndisc_constructor(struct neighbour *neigh); 83 static void ndisc_solicit(struct neighbour *neigh, struct sk_buff *skb); 84 static void ndisc_error_report(struct neighbour *neigh, struct sk_buff *skb); 85 static int pndisc_constructor(struct pneigh_entry *n); 86 static void pndisc_destructor(struct pneigh_entry *n); 87 static void pndisc_redo(struct sk_buff *skb); 88 89 static const struct neigh_ops ndisc_generic_ops = { 90 .family = AF_INET6, 91 .solicit = ndisc_solicit, 92 .error_report = ndisc_error_report, 93 .output = neigh_resolve_output, 94 .connected_output = neigh_connected_output, 95 }; 96 97 static const struct neigh_ops ndisc_hh_ops = { 98 .family = AF_INET6, 99 .solicit = ndisc_solicit, 100 .error_report = ndisc_error_report, 101 .output = neigh_resolve_output, 102 .connected_output = neigh_resolve_output, 103 }; 104 105 106 static const struct neigh_ops ndisc_direct_ops = { 107 .family = AF_INET6, 108 .output = neigh_direct_output, 109 .connected_output = neigh_direct_output, 110 }; 111 112 struct neigh_table nd_tbl = { 113 .family = AF_INET6, 114 .key_len = sizeof(struct in6_addr), 115 .protocol = cpu_to_be16(ETH_P_IPV6), 116 .hash = ndisc_hash, 117 .key_eq = ndisc_key_eq, 118 .constructor = ndisc_constructor, 119 .pconstructor = pndisc_constructor, 120 .pdestructor = pndisc_destructor, 121 .proxy_redo = pndisc_redo, 122 .allow_add = ndisc_allow_add, 123 .id = "ndisc_cache", 124 .parms = { 125 .tbl = &nd_tbl, 126 .reachable_time = ND_REACHABLE_TIME, 127 .data = { 128 [NEIGH_VAR_MCAST_PROBES] = 3, 129 [NEIGH_VAR_UCAST_PROBES] = 3, 130 [NEIGH_VAR_RETRANS_TIME] = ND_RETRANS_TIMER, 131 [NEIGH_VAR_BASE_REACHABLE_TIME] = ND_REACHABLE_TIME, 132 [NEIGH_VAR_DELAY_PROBE_TIME] = 5 * HZ, 133 [NEIGH_VAR_GC_STALETIME] = 60 * HZ, 134 [NEIGH_VAR_QUEUE_LEN_BYTES] = SK_WMEM_MAX, 135 [NEIGH_VAR_PROXY_QLEN] = 64, 136 [NEIGH_VAR_ANYCAST_DELAY] = 1 * HZ, 137 [NEIGH_VAR_PROXY_DELAY] = (8 * HZ) / 10, 138 }, 139 }, 140 .gc_interval = 30 * HZ, 141 .gc_thresh1 = 128, 142 .gc_thresh2 = 512, 143 .gc_thresh3 = 1024, 144 }; 145 EXPORT_SYMBOL_GPL(nd_tbl); 146 147 void __ndisc_fill_addr_option(struct sk_buff *skb, int type, void *data, 148 int data_len, int pad) 149 { 150 int space = __ndisc_opt_addr_space(data_len, pad); 151 u8 *opt = skb_put(skb, space); 152 153 opt[0] = type; 154 opt[1] = space>>3; 155 156 memset(opt + 2, 0, pad); 157 opt += pad; 158 space -= pad; 159 160 memcpy(opt+2, data, data_len); 161 data_len += 2; 162 opt += data_len; 163 space -= data_len; 164 if (space > 0) 165 memset(opt, 0, space); 166 } 167 EXPORT_SYMBOL_GPL(__ndisc_fill_addr_option); 168 169 static inline void ndisc_fill_addr_option(struct sk_buff *skb, int type, 170 void *data, u8 icmp6_type) 171 { 172 __ndisc_fill_addr_option(skb, type, data, skb->dev->addr_len, 173 ndisc_addr_option_pad(skb->dev->type)); 174 ndisc_ops_fill_addr_option(skb->dev, skb, icmp6_type); 175 } 176 177 static inline void ndisc_fill_redirect_addr_option(struct sk_buff *skb, 178 void *ha, 179 const u8 *ops_data) 180 { 181 ndisc_fill_addr_option(skb, ND_OPT_TARGET_LL_ADDR, ha, NDISC_REDIRECT); 182 ndisc_ops_fill_redirect_addr_option(skb->dev, skb, ops_data); 183 } 184 185 static struct nd_opt_hdr *ndisc_next_option(struct nd_opt_hdr *cur, 186 struct nd_opt_hdr *end) 187 { 188 int type; 189 if (!cur || !end || cur >= end) 190 return NULL; 191 type = cur->nd_opt_type; 192 do { 193 cur = ((void *)cur) + (cur->nd_opt_len << 3); 194 } while (cur < end && cur->nd_opt_type != type); 195 return cur <= end && cur->nd_opt_type == type ? cur : NULL; 196 } 197 198 static inline int ndisc_is_useropt(const struct net_device *dev, 199 struct nd_opt_hdr *opt) 200 { 201 return opt->nd_opt_type == ND_OPT_RDNSS || 202 opt->nd_opt_type == ND_OPT_DNSSL || 203 ndisc_ops_is_useropt(dev, opt->nd_opt_type); 204 } 205 206 static struct nd_opt_hdr *ndisc_next_useropt(const struct net_device *dev, 207 struct nd_opt_hdr *cur, 208 struct nd_opt_hdr *end) 209 { 210 if (!cur || !end || cur >= end) 211 return NULL; 212 do { 213 cur = ((void *)cur) + (cur->nd_opt_len << 3); 214 } while (cur < end && !ndisc_is_useropt(dev, cur)); 215 return cur <= end && ndisc_is_useropt(dev, cur) ? cur : NULL; 216 } 217 218 struct ndisc_options *ndisc_parse_options(const struct net_device *dev, 219 u8 *opt, int opt_len, 220 struct ndisc_options *ndopts) 221 { 222 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)opt; 223 224 if (!nd_opt || opt_len < 0 || !ndopts) 225 return NULL; 226 memset(ndopts, 0, sizeof(*ndopts)); 227 while (opt_len) { 228 int l; 229 if (opt_len < sizeof(struct nd_opt_hdr)) 230 return NULL; 231 l = nd_opt->nd_opt_len << 3; 232 if (opt_len < l || l == 0) 233 return NULL; 234 if (ndisc_ops_parse_options(dev, nd_opt, ndopts)) 235 goto next_opt; 236 switch (nd_opt->nd_opt_type) { 237 case ND_OPT_SOURCE_LL_ADDR: 238 case ND_OPT_TARGET_LL_ADDR: 239 case ND_OPT_MTU: 240 case ND_OPT_NONCE: 241 case ND_OPT_REDIRECT_HDR: 242 if (ndopts->nd_opt_array[nd_opt->nd_opt_type]) { 243 ND_PRINTK(2, warn, 244 "%s: duplicated ND6 option found: type=%d\n", 245 __func__, nd_opt->nd_opt_type); 246 } else { 247 ndopts->nd_opt_array[nd_opt->nd_opt_type] = nd_opt; 248 } 249 break; 250 case ND_OPT_PREFIX_INFO: 251 ndopts->nd_opts_pi_end = nd_opt; 252 if (!ndopts->nd_opt_array[nd_opt->nd_opt_type]) 253 ndopts->nd_opt_array[nd_opt->nd_opt_type] = nd_opt; 254 break; 255 #ifdef CONFIG_IPV6_ROUTE_INFO 256 case ND_OPT_ROUTE_INFO: 257 ndopts->nd_opts_ri_end = nd_opt; 258 if (!ndopts->nd_opts_ri) 259 ndopts->nd_opts_ri = nd_opt; 260 break; 261 #endif 262 default: 263 if (ndisc_is_useropt(dev, nd_opt)) { 264 ndopts->nd_useropts_end = nd_opt; 265 if (!ndopts->nd_useropts) 266 ndopts->nd_useropts = nd_opt; 267 } else { 268 /* 269 * Unknown options must be silently ignored, 270 * to accommodate future extension to the 271 * protocol. 272 */ 273 ND_PRINTK(2, notice, 274 "%s: ignored unsupported option; type=%d, len=%d\n", 275 __func__, 276 nd_opt->nd_opt_type, 277 nd_opt->nd_opt_len); 278 } 279 } 280 next_opt: 281 opt_len -= l; 282 nd_opt = ((void *)nd_opt) + l; 283 } 284 return ndopts; 285 } 286 287 int ndisc_mc_map(const struct in6_addr *addr, char *buf, struct net_device *dev, int dir) 288 { 289 switch (dev->type) { 290 case ARPHRD_ETHER: 291 case ARPHRD_IEEE802: /* Not sure. Check it later. --ANK */ 292 case ARPHRD_FDDI: 293 ipv6_eth_mc_map(addr, buf); 294 return 0; 295 case ARPHRD_ARCNET: 296 ipv6_arcnet_mc_map(addr, buf); 297 return 0; 298 case ARPHRD_INFINIBAND: 299 ipv6_ib_mc_map(addr, dev->broadcast, buf); 300 return 0; 301 case ARPHRD_IPGRE: 302 return ipv6_ipgre_mc_map(addr, dev->broadcast, buf); 303 default: 304 if (dir) { 305 memcpy(buf, dev->broadcast, dev->addr_len); 306 return 0; 307 } 308 } 309 return -EINVAL; 310 } 311 EXPORT_SYMBOL(ndisc_mc_map); 312 313 static u32 ndisc_hash(const void *pkey, 314 const struct net_device *dev, 315 __u32 *hash_rnd) 316 { 317 return ndisc_hashfn(pkey, dev, hash_rnd); 318 } 319 320 static bool ndisc_key_eq(const struct neighbour *n, const void *pkey) 321 { 322 return neigh_key_eq128(n, pkey); 323 } 324 325 static int ndisc_constructor(struct neighbour *neigh) 326 { 327 struct in6_addr *addr = (struct in6_addr *)&neigh->primary_key; 328 struct net_device *dev = neigh->dev; 329 struct inet6_dev *in6_dev; 330 struct neigh_parms *parms; 331 bool is_multicast = ipv6_addr_is_multicast(addr); 332 333 in6_dev = in6_dev_get(dev); 334 if (!in6_dev) { 335 return -EINVAL; 336 } 337 338 parms = in6_dev->nd_parms; 339 __neigh_parms_put(neigh->parms); 340 neigh->parms = neigh_parms_clone(parms); 341 342 neigh->type = is_multicast ? RTN_MULTICAST : RTN_UNICAST; 343 if (!dev->header_ops) { 344 neigh->nud_state = NUD_NOARP; 345 neigh->ops = &ndisc_direct_ops; 346 neigh->output = neigh_direct_output; 347 } else { 348 if (is_multicast) { 349 neigh->nud_state = NUD_NOARP; 350 ndisc_mc_map(addr, neigh->ha, dev, 1); 351 } else if (dev->flags&(IFF_NOARP|IFF_LOOPBACK)) { 352 neigh->nud_state = NUD_NOARP; 353 memcpy(neigh->ha, dev->dev_addr, dev->addr_len); 354 if (dev->flags&IFF_LOOPBACK) 355 neigh->type = RTN_LOCAL; 356 } else if (dev->flags&IFF_POINTOPOINT) { 357 neigh->nud_state = NUD_NOARP; 358 memcpy(neigh->ha, dev->broadcast, dev->addr_len); 359 } 360 if (dev->header_ops->cache) 361 neigh->ops = &ndisc_hh_ops; 362 else 363 neigh->ops = &ndisc_generic_ops; 364 if (neigh->nud_state&NUD_VALID) 365 neigh->output = neigh->ops->connected_output; 366 else 367 neigh->output = neigh->ops->output; 368 } 369 in6_dev_put(in6_dev); 370 return 0; 371 } 372 373 static int pndisc_constructor(struct pneigh_entry *n) 374 { 375 struct in6_addr *addr = (struct in6_addr *)&n->key; 376 struct in6_addr maddr; 377 struct net_device *dev = n->dev; 378 379 if (!dev || !__in6_dev_get(dev)) 380 return -EINVAL; 381 addrconf_addr_solict_mult(addr, &maddr); 382 ipv6_dev_mc_inc(dev, &maddr); 383 return 0; 384 } 385 386 static void pndisc_destructor(struct pneigh_entry *n) 387 { 388 struct in6_addr *addr = (struct in6_addr *)&n->key; 389 struct in6_addr maddr; 390 struct net_device *dev = n->dev; 391 392 if (!dev || !__in6_dev_get(dev)) 393 return; 394 addrconf_addr_solict_mult(addr, &maddr); 395 ipv6_dev_mc_dec(dev, &maddr); 396 } 397 398 /* called with rtnl held */ 399 static bool ndisc_allow_add(const struct net_device *dev, 400 struct netlink_ext_ack *extack) 401 { 402 struct inet6_dev *idev = __in6_dev_get(dev); 403 404 if (!idev || idev->cnf.disable_ipv6) { 405 NL_SET_ERR_MSG(extack, "IPv6 is disabled on this device"); 406 return false; 407 } 408 409 return true; 410 } 411 412 static struct sk_buff *ndisc_alloc_skb(struct net_device *dev, 413 int len) 414 { 415 int hlen = LL_RESERVED_SPACE(dev); 416 int tlen = dev->needed_tailroom; 417 struct sock *sk = dev_net(dev)->ipv6.ndisc_sk; 418 struct sk_buff *skb; 419 420 skb = alloc_skb(hlen + sizeof(struct ipv6hdr) + len + tlen, GFP_ATOMIC); 421 if (!skb) { 422 ND_PRINTK(0, err, "ndisc: %s failed to allocate an skb\n", 423 __func__); 424 return NULL; 425 } 426 427 skb->protocol = htons(ETH_P_IPV6); 428 skb->dev = dev; 429 430 skb_reserve(skb, hlen + sizeof(struct ipv6hdr)); 431 skb_reset_transport_header(skb); 432 433 /* Manually assign socket ownership as we avoid calling 434 * sock_alloc_send_pskb() to bypass wmem buffer limits 435 */ 436 skb_set_owner_w(skb, sk); 437 438 return skb; 439 } 440 441 static void ip6_nd_hdr(struct sk_buff *skb, 442 const struct in6_addr *saddr, 443 const struct in6_addr *daddr, 444 int hop_limit, int len) 445 { 446 struct ipv6hdr *hdr; 447 struct inet6_dev *idev; 448 unsigned tclass; 449 450 rcu_read_lock(); 451 idev = __in6_dev_get(skb->dev); 452 tclass = idev ? idev->cnf.ndisc_tclass : 0; 453 rcu_read_unlock(); 454 455 skb_push(skb, sizeof(*hdr)); 456 skb_reset_network_header(skb); 457 hdr = ipv6_hdr(skb); 458 459 ip6_flow_hdr(hdr, tclass, 0); 460 461 hdr->payload_len = htons(len); 462 hdr->nexthdr = IPPROTO_ICMPV6; 463 hdr->hop_limit = hop_limit; 464 465 hdr->saddr = *saddr; 466 hdr->daddr = *daddr; 467 } 468 469 static void ndisc_send_skb(struct sk_buff *skb, 470 const struct in6_addr *daddr, 471 const struct in6_addr *saddr) 472 { 473 struct dst_entry *dst = skb_dst(skb); 474 struct net *net = dev_net(skb->dev); 475 struct sock *sk = net->ipv6.ndisc_sk; 476 struct inet6_dev *idev; 477 int err; 478 struct icmp6hdr *icmp6h = icmp6_hdr(skb); 479 u8 type; 480 481 type = icmp6h->icmp6_type; 482 483 if (!dst) { 484 struct flowi6 fl6; 485 int oif = skb->dev->ifindex; 486 487 icmpv6_flow_init(sk, &fl6, type, saddr, daddr, oif); 488 dst = icmp6_dst_alloc(skb->dev, &fl6); 489 if (IS_ERR(dst)) { 490 kfree_skb(skb); 491 return; 492 } 493 494 skb_dst_set(skb, dst); 495 } 496 497 icmp6h->icmp6_cksum = csum_ipv6_magic(saddr, daddr, skb->len, 498 IPPROTO_ICMPV6, 499 csum_partial(icmp6h, 500 skb->len, 0)); 501 502 ip6_nd_hdr(skb, saddr, daddr, inet6_sk(sk)->hop_limit, skb->len); 503 504 rcu_read_lock(); 505 idev = __in6_dev_get(dst->dev); 506 IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUT, skb->len); 507 508 err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT, 509 net, sk, skb, NULL, dst->dev, 510 dst_output); 511 if (!err) { 512 ICMP6MSGOUT_INC_STATS(net, idev, type); 513 ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS); 514 } 515 516 rcu_read_unlock(); 517 } 518 519 void ndisc_send_na(struct net_device *dev, const struct in6_addr *daddr, 520 const struct in6_addr *solicited_addr, 521 bool router, bool solicited, bool override, bool inc_opt) 522 { 523 struct sk_buff *skb; 524 struct in6_addr tmpaddr; 525 struct inet6_ifaddr *ifp; 526 const struct in6_addr *src_addr; 527 struct nd_msg *msg; 528 int optlen = 0; 529 530 /* for anycast or proxy, solicited_addr != src_addr */ 531 ifp = ipv6_get_ifaddr(dev_net(dev), solicited_addr, dev, 1); 532 if (ifp) { 533 src_addr = solicited_addr; 534 if (ifp->flags & IFA_F_OPTIMISTIC) 535 override = false; 536 inc_opt |= ifp->idev->cnf.force_tllao; 537 in6_ifa_put(ifp); 538 } else { 539 if (ipv6_dev_get_saddr(dev_net(dev), dev, daddr, 540 inet6_sk(dev_net(dev)->ipv6.ndisc_sk)->srcprefs, 541 &tmpaddr)) 542 return; 543 src_addr = &tmpaddr; 544 } 545 546 if (!dev->addr_len) 547 inc_opt = false; 548 if (inc_opt) 549 optlen += ndisc_opt_addr_space(dev, 550 NDISC_NEIGHBOUR_ADVERTISEMENT); 551 552 skb = ndisc_alloc_skb(dev, sizeof(*msg) + optlen); 553 if (!skb) 554 return; 555 556 msg = skb_put(skb, sizeof(*msg)); 557 *msg = (struct nd_msg) { 558 .icmph = { 559 .icmp6_type = NDISC_NEIGHBOUR_ADVERTISEMENT, 560 .icmp6_router = router, 561 .icmp6_solicited = solicited, 562 .icmp6_override = override, 563 }, 564 .target = *solicited_addr, 565 }; 566 567 if (inc_opt) 568 ndisc_fill_addr_option(skb, ND_OPT_TARGET_LL_ADDR, 569 dev->dev_addr, 570 NDISC_NEIGHBOUR_ADVERTISEMENT); 571 572 ndisc_send_skb(skb, daddr, src_addr); 573 } 574 575 static void ndisc_send_unsol_na(struct net_device *dev) 576 { 577 struct inet6_dev *idev; 578 struct inet6_ifaddr *ifa; 579 580 idev = in6_dev_get(dev); 581 if (!idev) 582 return; 583 584 read_lock_bh(&idev->lock); 585 list_for_each_entry(ifa, &idev->addr_list, if_list) { 586 /* skip tentative addresses until dad completes */ 587 if (ifa->flags & IFA_F_TENTATIVE && 588 !(ifa->flags & IFA_F_OPTIMISTIC)) 589 continue; 590 591 ndisc_send_na(dev, &in6addr_linklocal_allnodes, &ifa->addr, 592 /*router=*/ !!idev->cnf.forwarding, 593 /*solicited=*/ false, /*override=*/ true, 594 /*inc_opt=*/ true); 595 } 596 read_unlock_bh(&idev->lock); 597 598 in6_dev_put(idev); 599 } 600 601 void ndisc_send_ns(struct net_device *dev, const struct in6_addr *solicit, 602 const struct in6_addr *daddr, const struct in6_addr *saddr, 603 u64 nonce) 604 { 605 struct sk_buff *skb; 606 struct in6_addr addr_buf; 607 int inc_opt = dev->addr_len; 608 int optlen = 0; 609 struct nd_msg *msg; 610 611 if (!saddr) { 612 if (ipv6_get_lladdr(dev, &addr_buf, 613 (IFA_F_TENTATIVE|IFA_F_OPTIMISTIC))) 614 return; 615 saddr = &addr_buf; 616 } 617 618 if (ipv6_addr_any(saddr)) 619 inc_opt = false; 620 if (inc_opt) 621 optlen += ndisc_opt_addr_space(dev, 622 NDISC_NEIGHBOUR_SOLICITATION); 623 if (nonce != 0) 624 optlen += 8; 625 626 skb = ndisc_alloc_skb(dev, sizeof(*msg) + optlen); 627 if (!skb) 628 return; 629 630 msg = skb_put(skb, sizeof(*msg)); 631 *msg = (struct nd_msg) { 632 .icmph = { 633 .icmp6_type = NDISC_NEIGHBOUR_SOLICITATION, 634 }, 635 .target = *solicit, 636 }; 637 638 if (inc_opt) 639 ndisc_fill_addr_option(skb, ND_OPT_SOURCE_LL_ADDR, 640 dev->dev_addr, 641 NDISC_NEIGHBOUR_SOLICITATION); 642 if (nonce != 0) { 643 u8 *opt = skb_put(skb, 8); 644 645 opt[0] = ND_OPT_NONCE; 646 opt[1] = 8 >> 3; 647 memcpy(opt + 2, &nonce, 6); 648 } 649 650 ndisc_send_skb(skb, daddr, saddr); 651 } 652 653 void ndisc_send_rs(struct net_device *dev, const struct in6_addr *saddr, 654 const struct in6_addr *daddr) 655 { 656 struct sk_buff *skb; 657 struct rs_msg *msg; 658 int send_sllao = dev->addr_len; 659 int optlen = 0; 660 661 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD 662 /* 663 * According to section 2.2 of RFC 4429, we must not 664 * send router solicitations with a sllao from 665 * optimistic addresses, but we may send the solicitation 666 * if we don't include the sllao. So here we check 667 * if our address is optimistic, and if so, we 668 * suppress the inclusion of the sllao. 669 */ 670 if (send_sllao) { 671 struct inet6_ifaddr *ifp = ipv6_get_ifaddr(dev_net(dev), saddr, 672 dev, 1); 673 if (ifp) { 674 if (ifp->flags & IFA_F_OPTIMISTIC) { 675 send_sllao = 0; 676 } 677 in6_ifa_put(ifp); 678 } else { 679 send_sllao = 0; 680 } 681 } 682 #endif 683 if (send_sllao) 684 optlen += ndisc_opt_addr_space(dev, NDISC_ROUTER_SOLICITATION); 685 686 skb = ndisc_alloc_skb(dev, sizeof(*msg) + optlen); 687 if (!skb) 688 return; 689 690 msg = skb_put(skb, sizeof(*msg)); 691 *msg = (struct rs_msg) { 692 .icmph = { 693 .icmp6_type = NDISC_ROUTER_SOLICITATION, 694 }, 695 }; 696 697 if (send_sllao) 698 ndisc_fill_addr_option(skb, ND_OPT_SOURCE_LL_ADDR, 699 dev->dev_addr, 700 NDISC_ROUTER_SOLICITATION); 701 702 ndisc_send_skb(skb, daddr, saddr); 703 } 704 705 706 static void ndisc_error_report(struct neighbour *neigh, struct sk_buff *skb) 707 { 708 /* 709 * "The sender MUST return an ICMP 710 * destination unreachable" 711 */ 712 dst_link_failure(skb); 713 kfree_skb(skb); 714 } 715 716 /* Called with locked neigh: either read or both */ 717 718 static void ndisc_solicit(struct neighbour *neigh, struct sk_buff *skb) 719 { 720 struct in6_addr *saddr = NULL; 721 struct in6_addr mcaddr; 722 struct net_device *dev = neigh->dev; 723 struct in6_addr *target = (struct in6_addr *)&neigh->primary_key; 724 int probes = atomic_read(&neigh->probes); 725 726 if (skb && ipv6_chk_addr_and_flags(dev_net(dev), &ipv6_hdr(skb)->saddr, 727 dev, false, 1, 728 IFA_F_TENTATIVE|IFA_F_OPTIMISTIC)) 729 saddr = &ipv6_hdr(skb)->saddr; 730 probes -= NEIGH_VAR(neigh->parms, UCAST_PROBES); 731 if (probes < 0) { 732 if (!(neigh->nud_state & NUD_VALID)) { 733 ND_PRINTK(1, dbg, 734 "%s: trying to ucast probe in NUD_INVALID: %pI6\n", 735 __func__, target); 736 } 737 ndisc_send_ns(dev, target, target, saddr, 0); 738 } else if ((probes -= NEIGH_VAR(neigh->parms, APP_PROBES)) < 0) { 739 neigh_app_ns(neigh); 740 } else { 741 addrconf_addr_solict_mult(target, &mcaddr); 742 ndisc_send_ns(dev, target, &mcaddr, saddr, 0); 743 } 744 } 745 746 static int pndisc_is_router(const void *pkey, 747 struct net_device *dev) 748 { 749 struct pneigh_entry *n; 750 int ret = -1; 751 752 read_lock_bh(&nd_tbl.lock); 753 n = __pneigh_lookup(&nd_tbl, dev_net(dev), pkey, dev); 754 if (n) 755 ret = !!(n->flags & NTF_ROUTER); 756 read_unlock_bh(&nd_tbl.lock); 757 758 return ret; 759 } 760 761 void ndisc_update(const struct net_device *dev, struct neighbour *neigh, 762 const u8 *lladdr, u8 new, u32 flags, u8 icmp6_type, 763 struct ndisc_options *ndopts) 764 { 765 neigh_update(neigh, lladdr, new, flags, 0); 766 /* report ndisc ops about neighbour update */ 767 ndisc_ops_update(dev, neigh, flags, icmp6_type, ndopts); 768 } 769 770 static void ndisc_recv_ns(struct sk_buff *skb) 771 { 772 struct nd_msg *msg = (struct nd_msg *)skb_transport_header(skb); 773 const struct in6_addr *saddr = &ipv6_hdr(skb)->saddr; 774 const struct in6_addr *daddr = &ipv6_hdr(skb)->daddr; 775 u8 *lladdr = NULL; 776 u32 ndoptlen = skb_tail_pointer(skb) - (skb_transport_header(skb) + 777 offsetof(struct nd_msg, opt)); 778 struct ndisc_options ndopts; 779 struct net_device *dev = skb->dev; 780 struct inet6_ifaddr *ifp; 781 struct inet6_dev *idev = NULL; 782 struct neighbour *neigh; 783 int dad = ipv6_addr_any(saddr); 784 bool inc; 785 int is_router = -1; 786 u64 nonce = 0; 787 788 if (skb->len < sizeof(struct nd_msg)) { 789 ND_PRINTK(2, warn, "NS: packet too short\n"); 790 return; 791 } 792 793 if (ipv6_addr_is_multicast(&msg->target)) { 794 ND_PRINTK(2, warn, "NS: multicast target address\n"); 795 return; 796 } 797 798 /* 799 * RFC2461 7.1.1: 800 * DAD has to be destined for solicited node multicast address. 801 */ 802 if (dad && !ipv6_addr_is_solict_mult(daddr)) { 803 ND_PRINTK(2, warn, "NS: bad DAD packet (wrong destination)\n"); 804 return; 805 } 806 807 if (!ndisc_parse_options(dev, msg->opt, ndoptlen, &ndopts)) { 808 ND_PRINTK(2, warn, "NS: invalid ND options\n"); 809 return; 810 } 811 812 if (ndopts.nd_opts_src_lladdr) { 813 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr, dev); 814 if (!lladdr) { 815 ND_PRINTK(2, warn, 816 "NS: invalid link-layer address length\n"); 817 return; 818 } 819 820 /* RFC2461 7.1.1: 821 * If the IP source address is the unspecified address, 822 * there MUST NOT be source link-layer address option 823 * in the message. 824 */ 825 if (dad) { 826 ND_PRINTK(2, warn, 827 "NS: bad DAD packet (link-layer address option)\n"); 828 return; 829 } 830 } 831 if (ndopts.nd_opts_nonce && ndopts.nd_opts_nonce->nd_opt_len == 1) 832 memcpy(&nonce, (u8 *)(ndopts.nd_opts_nonce + 1), 6); 833 834 inc = ipv6_addr_is_multicast(daddr); 835 836 ifp = ipv6_get_ifaddr(dev_net(dev), &msg->target, dev, 1); 837 if (ifp) { 838 have_ifp: 839 if (ifp->flags & (IFA_F_TENTATIVE|IFA_F_OPTIMISTIC)) { 840 if (dad) { 841 if (nonce != 0 && ifp->dad_nonce == nonce) { 842 u8 *np = (u8 *)&nonce; 843 /* Matching nonce if looped back */ 844 ND_PRINTK(2, notice, 845 "%s: IPv6 DAD loopback for address %pI6c nonce %pM ignored\n", 846 ifp->idev->dev->name, 847 &ifp->addr, np); 848 goto out; 849 } 850 /* 851 * We are colliding with another node 852 * who is doing DAD 853 * so fail our DAD process 854 */ 855 addrconf_dad_failure(skb, ifp); 856 return; 857 } else { 858 /* 859 * This is not a dad solicitation. 860 * If we are an optimistic node, 861 * we should respond. 862 * Otherwise, we should ignore it. 863 */ 864 if (!(ifp->flags & IFA_F_OPTIMISTIC)) 865 goto out; 866 } 867 } 868 869 idev = ifp->idev; 870 } else { 871 struct net *net = dev_net(dev); 872 873 /* perhaps an address on the master device */ 874 if (netif_is_l3_slave(dev)) { 875 struct net_device *mdev; 876 877 mdev = netdev_master_upper_dev_get_rcu(dev); 878 if (mdev) { 879 ifp = ipv6_get_ifaddr(net, &msg->target, mdev, 1); 880 if (ifp) 881 goto have_ifp; 882 } 883 } 884 885 idev = in6_dev_get(dev); 886 if (!idev) { 887 /* XXX: count this drop? */ 888 return; 889 } 890 891 if (ipv6_chk_acast_addr(net, dev, &msg->target) || 892 (idev->cnf.forwarding && 893 (net->ipv6.devconf_all->proxy_ndp || idev->cnf.proxy_ndp) && 894 (is_router = pndisc_is_router(&msg->target, dev)) >= 0)) { 895 if (!(NEIGH_CB(skb)->flags & LOCALLY_ENQUEUED) && 896 skb->pkt_type != PACKET_HOST && 897 inc && 898 NEIGH_VAR(idev->nd_parms, PROXY_DELAY) != 0) { 899 /* 900 * for anycast or proxy, 901 * sender should delay its response 902 * by a random time between 0 and 903 * MAX_ANYCAST_DELAY_TIME seconds. 904 * (RFC2461) -- yoshfuji 905 */ 906 struct sk_buff *n = skb_clone(skb, GFP_ATOMIC); 907 if (n) 908 pneigh_enqueue(&nd_tbl, idev->nd_parms, n); 909 goto out; 910 } 911 } else 912 goto out; 913 } 914 915 if (is_router < 0) 916 is_router = idev->cnf.forwarding; 917 918 if (dad) { 919 ndisc_send_na(dev, &in6addr_linklocal_allnodes, &msg->target, 920 !!is_router, false, (ifp != NULL), true); 921 goto out; 922 } 923 924 if (inc) 925 NEIGH_CACHE_STAT_INC(&nd_tbl, rcv_probes_mcast); 926 else 927 NEIGH_CACHE_STAT_INC(&nd_tbl, rcv_probes_ucast); 928 929 /* 930 * update / create cache entry 931 * for the source address 932 */ 933 neigh = __neigh_lookup(&nd_tbl, saddr, dev, 934 !inc || lladdr || !dev->addr_len); 935 if (neigh) 936 ndisc_update(dev, neigh, lladdr, NUD_STALE, 937 NEIGH_UPDATE_F_WEAK_OVERRIDE| 938 NEIGH_UPDATE_F_OVERRIDE, 939 NDISC_NEIGHBOUR_SOLICITATION, &ndopts); 940 if (neigh || !dev->header_ops) { 941 ndisc_send_na(dev, saddr, &msg->target, !!is_router, 942 true, (ifp != NULL && inc), inc); 943 if (neigh) 944 neigh_release(neigh); 945 } 946 947 out: 948 if (ifp) 949 in6_ifa_put(ifp); 950 else 951 in6_dev_put(idev); 952 } 953 954 static void ndisc_recv_na(struct sk_buff *skb) 955 { 956 struct nd_msg *msg = (struct nd_msg *)skb_transport_header(skb); 957 struct in6_addr *saddr = &ipv6_hdr(skb)->saddr; 958 const struct in6_addr *daddr = &ipv6_hdr(skb)->daddr; 959 u8 *lladdr = NULL; 960 u32 ndoptlen = skb_tail_pointer(skb) - (skb_transport_header(skb) + 961 offsetof(struct nd_msg, opt)); 962 struct ndisc_options ndopts; 963 struct net_device *dev = skb->dev; 964 struct inet6_dev *idev = __in6_dev_get(dev); 965 struct inet6_ifaddr *ifp; 966 struct neighbour *neigh; 967 968 if (skb->len < sizeof(struct nd_msg)) { 969 ND_PRINTK(2, warn, "NA: packet too short\n"); 970 return; 971 } 972 973 if (ipv6_addr_is_multicast(&msg->target)) { 974 ND_PRINTK(2, warn, "NA: target address is multicast\n"); 975 return; 976 } 977 978 if (ipv6_addr_is_multicast(daddr) && 979 msg->icmph.icmp6_solicited) { 980 ND_PRINTK(2, warn, "NA: solicited NA is multicasted\n"); 981 return; 982 } 983 984 /* For some 802.11 wireless deployments (and possibly other networks), 985 * there will be a NA proxy and unsolicitd packets are attacks 986 * and thus should not be accepted. 987 */ 988 if (!msg->icmph.icmp6_solicited && idev && 989 idev->cnf.drop_unsolicited_na) 990 return; 991 992 if (!ndisc_parse_options(dev, msg->opt, ndoptlen, &ndopts)) { 993 ND_PRINTK(2, warn, "NS: invalid ND option\n"); 994 return; 995 } 996 if (ndopts.nd_opts_tgt_lladdr) { 997 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr, dev); 998 if (!lladdr) { 999 ND_PRINTK(2, warn, 1000 "NA: invalid link-layer address length\n"); 1001 return; 1002 } 1003 } 1004 ifp = ipv6_get_ifaddr(dev_net(dev), &msg->target, dev, 1); 1005 if (ifp) { 1006 if (skb->pkt_type != PACKET_LOOPBACK 1007 && (ifp->flags & IFA_F_TENTATIVE)) { 1008 addrconf_dad_failure(skb, ifp); 1009 return; 1010 } 1011 /* What should we make now? The advertisement 1012 is invalid, but ndisc specs say nothing 1013 about it. It could be misconfiguration, or 1014 an smart proxy agent tries to help us :-) 1015 1016 We should not print the error if NA has been 1017 received from loopback - it is just our own 1018 unsolicited advertisement. 1019 */ 1020 if (skb->pkt_type != PACKET_LOOPBACK) 1021 ND_PRINTK(1, warn, 1022 "NA: %pM advertised our address %pI6c on %s!\n", 1023 eth_hdr(skb)->h_source, &ifp->addr, ifp->idev->dev->name); 1024 in6_ifa_put(ifp); 1025 return; 1026 } 1027 neigh = neigh_lookup(&nd_tbl, &msg->target, dev); 1028 1029 if (neigh) { 1030 u8 old_flags = neigh->flags; 1031 struct net *net = dev_net(dev); 1032 1033 if (neigh->nud_state & NUD_FAILED) 1034 goto out; 1035 1036 /* 1037 * Don't update the neighbor cache entry on a proxy NA from 1038 * ourselves because either the proxied node is off link or it 1039 * has already sent a NA to us. 1040 */ 1041 if (lladdr && !memcmp(lladdr, dev->dev_addr, dev->addr_len) && 1042 net->ipv6.devconf_all->forwarding && net->ipv6.devconf_all->proxy_ndp && 1043 pneigh_lookup(&nd_tbl, net, &msg->target, dev, 0)) { 1044 /* XXX: idev->cnf.proxy_ndp */ 1045 goto out; 1046 } 1047 1048 ndisc_update(dev, neigh, lladdr, 1049 msg->icmph.icmp6_solicited ? NUD_REACHABLE : NUD_STALE, 1050 NEIGH_UPDATE_F_WEAK_OVERRIDE| 1051 (msg->icmph.icmp6_override ? NEIGH_UPDATE_F_OVERRIDE : 0)| 1052 NEIGH_UPDATE_F_OVERRIDE_ISROUTER| 1053 (msg->icmph.icmp6_router ? NEIGH_UPDATE_F_ISROUTER : 0), 1054 NDISC_NEIGHBOUR_ADVERTISEMENT, &ndopts); 1055 1056 if ((old_flags & ~neigh->flags) & NTF_ROUTER) { 1057 /* 1058 * Change: router to host 1059 */ 1060 rt6_clean_tohost(dev_net(dev), saddr); 1061 } 1062 1063 out: 1064 neigh_release(neigh); 1065 } 1066 } 1067 1068 static void ndisc_recv_rs(struct sk_buff *skb) 1069 { 1070 struct rs_msg *rs_msg = (struct rs_msg *)skb_transport_header(skb); 1071 unsigned long ndoptlen = skb->len - sizeof(*rs_msg); 1072 struct neighbour *neigh; 1073 struct inet6_dev *idev; 1074 const struct in6_addr *saddr = &ipv6_hdr(skb)->saddr; 1075 struct ndisc_options ndopts; 1076 u8 *lladdr = NULL; 1077 1078 if (skb->len < sizeof(*rs_msg)) 1079 return; 1080 1081 idev = __in6_dev_get(skb->dev); 1082 if (!idev) { 1083 ND_PRINTK(1, err, "RS: can't find in6 device\n"); 1084 return; 1085 } 1086 1087 /* Don't accept RS if we're not in router mode */ 1088 if (!idev->cnf.forwarding) 1089 goto out; 1090 1091 /* 1092 * Don't update NCE if src = ::; 1093 * this implies that the source node has no ip address assigned yet. 1094 */ 1095 if (ipv6_addr_any(saddr)) 1096 goto out; 1097 1098 /* Parse ND options */ 1099 if (!ndisc_parse_options(skb->dev, rs_msg->opt, ndoptlen, &ndopts)) { 1100 ND_PRINTK(2, notice, "NS: invalid ND option, ignored\n"); 1101 goto out; 1102 } 1103 1104 if (ndopts.nd_opts_src_lladdr) { 1105 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr, 1106 skb->dev); 1107 if (!lladdr) 1108 goto out; 1109 } 1110 1111 neigh = __neigh_lookup(&nd_tbl, saddr, skb->dev, 1); 1112 if (neigh) { 1113 ndisc_update(skb->dev, neigh, lladdr, NUD_STALE, 1114 NEIGH_UPDATE_F_WEAK_OVERRIDE| 1115 NEIGH_UPDATE_F_OVERRIDE| 1116 NEIGH_UPDATE_F_OVERRIDE_ISROUTER, 1117 NDISC_ROUTER_SOLICITATION, &ndopts); 1118 neigh_release(neigh); 1119 } 1120 out: 1121 return; 1122 } 1123 1124 static void ndisc_ra_useropt(struct sk_buff *ra, struct nd_opt_hdr *opt) 1125 { 1126 struct icmp6hdr *icmp6h = (struct icmp6hdr *)skb_transport_header(ra); 1127 struct sk_buff *skb; 1128 struct nlmsghdr *nlh; 1129 struct nduseroptmsg *ndmsg; 1130 struct net *net = dev_net(ra->dev); 1131 int err; 1132 int base_size = NLMSG_ALIGN(sizeof(struct nduseroptmsg) 1133 + (opt->nd_opt_len << 3)); 1134 size_t msg_size = base_size + nla_total_size(sizeof(struct in6_addr)); 1135 1136 skb = nlmsg_new(msg_size, GFP_ATOMIC); 1137 if (!skb) { 1138 err = -ENOBUFS; 1139 goto errout; 1140 } 1141 1142 nlh = nlmsg_put(skb, 0, 0, RTM_NEWNDUSEROPT, base_size, 0); 1143 if (!nlh) { 1144 goto nla_put_failure; 1145 } 1146 1147 ndmsg = nlmsg_data(nlh); 1148 ndmsg->nduseropt_family = AF_INET6; 1149 ndmsg->nduseropt_ifindex = ra->dev->ifindex; 1150 ndmsg->nduseropt_icmp_type = icmp6h->icmp6_type; 1151 ndmsg->nduseropt_icmp_code = icmp6h->icmp6_code; 1152 ndmsg->nduseropt_opts_len = opt->nd_opt_len << 3; 1153 1154 memcpy(ndmsg + 1, opt, opt->nd_opt_len << 3); 1155 1156 if (nla_put_in6_addr(skb, NDUSEROPT_SRCADDR, &ipv6_hdr(ra)->saddr)) 1157 goto nla_put_failure; 1158 nlmsg_end(skb, nlh); 1159 1160 rtnl_notify(skb, net, 0, RTNLGRP_ND_USEROPT, NULL, GFP_ATOMIC); 1161 return; 1162 1163 nla_put_failure: 1164 nlmsg_free(skb); 1165 err = -EMSGSIZE; 1166 errout: 1167 rtnl_set_sk_err(net, RTNLGRP_ND_USEROPT, err); 1168 } 1169 1170 static void ndisc_router_discovery(struct sk_buff *skb) 1171 { 1172 struct ra_msg *ra_msg = (struct ra_msg *)skb_transport_header(skb); 1173 struct neighbour *neigh = NULL; 1174 struct inet6_dev *in6_dev; 1175 struct fib6_info *rt = NULL; 1176 struct net *net; 1177 int lifetime; 1178 struct ndisc_options ndopts; 1179 int optlen; 1180 unsigned int pref = 0; 1181 __u32 old_if_flags; 1182 bool send_ifinfo_notify = false; 1183 1184 __u8 *opt = (__u8 *)(ra_msg + 1); 1185 1186 optlen = (skb_tail_pointer(skb) - skb_transport_header(skb)) - 1187 sizeof(struct ra_msg); 1188 1189 ND_PRINTK(2, info, 1190 "RA: %s, dev: %s\n", 1191 __func__, skb->dev->name); 1192 if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) { 1193 ND_PRINTK(2, warn, "RA: source address is not link-local\n"); 1194 return; 1195 } 1196 if (optlen < 0) { 1197 ND_PRINTK(2, warn, "RA: packet too short\n"); 1198 return; 1199 } 1200 1201 #ifdef CONFIG_IPV6_NDISC_NODETYPE 1202 if (skb->ndisc_nodetype == NDISC_NODETYPE_HOST) { 1203 ND_PRINTK(2, warn, "RA: from host or unauthorized router\n"); 1204 return; 1205 } 1206 #endif 1207 1208 /* 1209 * set the RA_RECV flag in the interface 1210 */ 1211 1212 in6_dev = __in6_dev_get(skb->dev); 1213 if (!in6_dev) { 1214 ND_PRINTK(0, err, "RA: can't find inet6 device for %s\n", 1215 skb->dev->name); 1216 return; 1217 } 1218 1219 if (!ndisc_parse_options(skb->dev, opt, optlen, &ndopts)) { 1220 ND_PRINTK(2, warn, "RA: invalid ND options\n"); 1221 return; 1222 } 1223 1224 if (!ipv6_accept_ra(in6_dev)) { 1225 ND_PRINTK(2, info, 1226 "RA: %s, did not accept ra for dev: %s\n", 1227 __func__, skb->dev->name); 1228 goto skip_linkparms; 1229 } 1230 1231 #ifdef CONFIG_IPV6_NDISC_NODETYPE 1232 /* skip link-specific parameters from interior routers */ 1233 if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT) { 1234 ND_PRINTK(2, info, 1235 "RA: %s, nodetype is NODEFAULT, dev: %s\n", 1236 __func__, skb->dev->name); 1237 goto skip_linkparms; 1238 } 1239 #endif 1240 1241 if (in6_dev->if_flags & IF_RS_SENT) { 1242 /* 1243 * flag that an RA was received after an RS was sent 1244 * out on this interface. 1245 */ 1246 in6_dev->if_flags |= IF_RA_RCVD; 1247 } 1248 1249 /* 1250 * Remember the managed/otherconf flags from most recently 1251 * received RA message (RFC 2462) -- yoshfuji 1252 */ 1253 old_if_flags = in6_dev->if_flags; 1254 in6_dev->if_flags = (in6_dev->if_flags & ~(IF_RA_MANAGED | 1255 IF_RA_OTHERCONF)) | 1256 (ra_msg->icmph.icmp6_addrconf_managed ? 1257 IF_RA_MANAGED : 0) | 1258 (ra_msg->icmph.icmp6_addrconf_other ? 1259 IF_RA_OTHERCONF : 0); 1260 1261 if (old_if_flags != in6_dev->if_flags) 1262 send_ifinfo_notify = true; 1263 1264 if (!in6_dev->cnf.accept_ra_defrtr) { 1265 ND_PRINTK(2, info, 1266 "RA: %s, defrtr is false for dev: %s\n", 1267 __func__, skb->dev->name); 1268 goto skip_defrtr; 1269 } 1270 1271 /* Do not accept RA with source-addr found on local machine unless 1272 * accept_ra_from_local is set to true. 1273 */ 1274 net = dev_net(in6_dev->dev); 1275 if (!in6_dev->cnf.accept_ra_from_local && 1276 ipv6_chk_addr(net, &ipv6_hdr(skb)->saddr, in6_dev->dev, 0)) { 1277 ND_PRINTK(2, info, 1278 "RA from local address detected on dev: %s: default router ignored\n", 1279 skb->dev->name); 1280 goto skip_defrtr; 1281 } 1282 1283 lifetime = ntohs(ra_msg->icmph.icmp6_rt_lifetime); 1284 1285 #ifdef CONFIG_IPV6_ROUTER_PREF 1286 pref = ra_msg->icmph.icmp6_router_pref; 1287 /* 10b is handled as if it were 00b (medium) */ 1288 if (pref == ICMPV6_ROUTER_PREF_INVALID || 1289 !in6_dev->cnf.accept_ra_rtr_pref) 1290 pref = ICMPV6_ROUTER_PREF_MEDIUM; 1291 #endif 1292 1293 rt = rt6_get_dflt_router(net, &ipv6_hdr(skb)->saddr, skb->dev); 1294 1295 if (rt) { 1296 neigh = ip6_neigh_lookup(&rt->fib6_nh.fib_nh_gw6, 1297 rt->fib6_nh.fib_nh_dev, NULL, 1298 &ipv6_hdr(skb)->saddr); 1299 if (!neigh) { 1300 ND_PRINTK(0, err, 1301 "RA: %s got default router without neighbour\n", 1302 __func__); 1303 fib6_info_release(rt); 1304 return; 1305 } 1306 } 1307 if (rt && lifetime == 0) { 1308 ip6_del_rt(net, rt); 1309 rt = NULL; 1310 } 1311 1312 ND_PRINTK(3, info, "RA: rt: %p lifetime: %d, for dev: %s\n", 1313 rt, lifetime, skb->dev->name); 1314 if (!rt && lifetime) { 1315 ND_PRINTK(3, info, "RA: adding default router\n"); 1316 1317 rt = rt6_add_dflt_router(net, &ipv6_hdr(skb)->saddr, 1318 skb->dev, pref); 1319 if (!rt) { 1320 ND_PRINTK(0, err, 1321 "RA: %s failed to add default route\n", 1322 __func__); 1323 return; 1324 } 1325 1326 neigh = ip6_neigh_lookup(&rt->fib6_nh.fib_nh_gw6, 1327 rt->fib6_nh.fib_nh_dev, NULL, 1328 &ipv6_hdr(skb)->saddr); 1329 if (!neigh) { 1330 ND_PRINTK(0, err, 1331 "RA: %s got default router without neighbour\n", 1332 __func__); 1333 fib6_info_release(rt); 1334 return; 1335 } 1336 neigh->flags |= NTF_ROUTER; 1337 } else if (rt) { 1338 rt->fib6_flags = (rt->fib6_flags & ~RTF_PREF_MASK) | RTF_PREF(pref); 1339 } 1340 1341 if (rt) 1342 fib6_set_expires(rt, jiffies + (HZ * lifetime)); 1343 if (in6_dev->cnf.accept_ra_min_hop_limit < 256 && 1344 ra_msg->icmph.icmp6_hop_limit) { 1345 if (in6_dev->cnf.accept_ra_min_hop_limit <= ra_msg->icmph.icmp6_hop_limit) { 1346 in6_dev->cnf.hop_limit = ra_msg->icmph.icmp6_hop_limit; 1347 fib6_metric_set(rt, RTAX_HOPLIMIT, 1348 ra_msg->icmph.icmp6_hop_limit); 1349 } else { 1350 ND_PRINTK(2, warn, "RA: Got route advertisement with lower hop_limit than minimum\n"); 1351 } 1352 } 1353 1354 skip_defrtr: 1355 1356 /* 1357 * Update Reachable Time and Retrans Timer 1358 */ 1359 1360 if (in6_dev->nd_parms) { 1361 unsigned long rtime = ntohl(ra_msg->retrans_timer); 1362 1363 if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/HZ) { 1364 rtime = (rtime*HZ)/1000; 1365 if (rtime < HZ/10) 1366 rtime = HZ/10; 1367 NEIGH_VAR_SET(in6_dev->nd_parms, RETRANS_TIME, rtime); 1368 in6_dev->tstamp = jiffies; 1369 send_ifinfo_notify = true; 1370 } 1371 1372 rtime = ntohl(ra_msg->reachable_time); 1373 if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/(3*HZ)) { 1374 rtime = (rtime*HZ)/1000; 1375 1376 if (rtime < HZ/10) 1377 rtime = HZ/10; 1378 1379 if (rtime != NEIGH_VAR(in6_dev->nd_parms, BASE_REACHABLE_TIME)) { 1380 NEIGH_VAR_SET(in6_dev->nd_parms, 1381 BASE_REACHABLE_TIME, rtime); 1382 NEIGH_VAR_SET(in6_dev->nd_parms, 1383 GC_STALETIME, 3 * rtime); 1384 in6_dev->nd_parms->reachable_time = neigh_rand_reach_time(rtime); 1385 in6_dev->tstamp = jiffies; 1386 send_ifinfo_notify = true; 1387 } 1388 } 1389 } 1390 1391 /* 1392 * Send a notify if RA changed managed/otherconf flags or timer settings 1393 */ 1394 if (send_ifinfo_notify) 1395 inet6_ifinfo_notify(RTM_NEWLINK, in6_dev); 1396 1397 skip_linkparms: 1398 1399 /* 1400 * Process options. 1401 */ 1402 1403 if (!neigh) 1404 neigh = __neigh_lookup(&nd_tbl, &ipv6_hdr(skb)->saddr, 1405 skb->dev, 1); 1406 if (neigh) { 1407 u8 *lladdr = NULL; 1408 if (ndopts.nd_opts_src_lladdr) { 1409 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr, 1410 skb->dev); 1411 if (!lladdr) { 1412 ND_PRINTK(2, warn, 1413 "RA: invalid link-layer address length\n"); 1414 goto out; 1415 } 1416 } 1417 ndisc_update(skb->dev, neigh, lladdr, NUD_STALE, 1418 NEIGH_UPDATE_F_WEAK_OVERRIDE| 1419 NEIGH_UPDATE_F_OVERRIDE| 1420 NEIGH_UPDATE_F_OVERRIDE_ISROUTER| 1421 NEIGH_UPDATE_F_ISROUTER, 1422 NDISC_ROUTER_ADVERTISEMENT, &ndopts); 1423 } 1424 1425 if (!ipv6_accept_ra(in6_dev)) { 1426 ND_PRINTK(2, info, 1427 "RA: %s, accept_ra is false for dev: %s\n", 1428 __func__, skb->dev->name); 1429 goto out; 1430 } 1431 1432 #ifdef CONFIG_IPV6_ROUTE_INFO 1433 if (!in6_dev->cnf.accept_ra_from_local && 1434 ipv6_chk_addr(dev_net(in6_dev->dev), &ipv6_hdr(skb)->saddr, 1435 in6_dev->dev, 0)) { 1436 ND_PRINTK(2, info, 1437 "RA from local address detected on dev: %s: router info ignored.\n", 1438 skb->dev->name); 1439 goto skip_routeinfo; 1440 } 1441 1442 if (in6_dev->cnf.accept_ra_rtr_pref && ndopts.nd_opts_ri) { 1443 struct nd_opt_hdr *p; 1444 for (p = ndopts.nd_opts_ri; 1445 p; 1446 p = ndisc_next_option(p, ndopts.nd_opts_ri_end)) { 1447 struct route_info *ri = (struct route_info *)p; 1448 #ifdef CONFIG_IPV6_NDISC_NODETYPE 1449 if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT && 1450 ri->prefix_len == 0) 1451 continue; 1452 #endif 1453 if (ri->prefix_len == 0 && 1454 !in6_dev->cnf.accept_ra_defrtr) 1455 continue; 1456 if (ri->prefix_len < in6_dev->cnf.accept_ra_rt_info_min_plen) 1457 continue; 1458 if (ri->prefix_len > in6_dev->cnf.accept_ra_rt_info_max_plen) 1459 continue; 1460 rt6_route_rcv(skb->dev, (u8 *)p, (p->nd_opt_len) << 3, 1461 &ipv6_hdr(skb)->saddr); 1462 } 1463 } 1464 1465 skip_routeinfo: 1466 #endif 1467 1468 #ifdef CONFIG_IPV6_NDISC_NODETYPE 1469 /* skip link-specific ndopts from interior routers */ 1470 if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT) { 1471 ND_PRINTK(2, info, 1472 "RA: %s, nodetype is NODEFAULT (interior routes), dev: %s\n", 1473 __func__, skb->dev->name); 1474 goto out; 1475 } 1476 #endif 1477 1478 if (in6_dev->cnf.accept_ra_pinfo && ndopts.nd_opts_pi) { 1479 struct nd_opt_hdr *p; 1480 for (p = ndopts.nd_opts_pi; 1481 p; 1482 p = ndisc_next_option(p, ndopts.nd_opts_pi_end)) { 1483 addrconf_prefix_rcv(skb->dev, (u8 *)p, 1484 (p->nd_opt_len) << 3, 1485 ndopts.nd_opts_src_lladdr != NULL); 1486 } 1487 } 1488 1489 if (ndopts.nd_opts_mtu && in6_dev->cnf.accept_ra_mtu) { 1490 __be32 n; 1491 u32 mtu; 1492 1493 memcpy(&n, ((u8 *)(ndopts.nd_opts_mtu+1))+2, sizeof(mtu)); 1494 mtu = ntohl(n); 1495 1496 if (mtu < IPV6_MIN_MTU || mtu > skb->dev->mtu) { 1497 ND_PRINTK(2, warn, "RA: invalid mtu: %d\n", mtu); 1498 } else if (in6_dev->cnf.mtu6 != mtu) { 1499 in6_dev->cnf.mtu6 = mtu; 1500 fib6_metric_set(rt, RTAX_MTU, mtu); 1501 rt6_mtu_change(skb->dev, mtu); 1502 } 1503 } 1504 1505 if (ndopts.nd_useropts) { 1506 struct nd_opt_hdr *p; 1507 for (p = ndopts.nd_useropts; 1508 p; 1509 p = ndisc_next_useropt(skb->dev, p, 1510 ndopts.nd_useropts_end)) { 1511 ndisc_ra_useropt(skb, p); 1512 } 1513 } 1514 1515 if (ndopts.nd_opts_tgt_lladdr || ndopts.nd_opts_rh) { 1516 ND_PRINTK(2, warn, "RA: invalid RA options\n"); 1517 } 1518 out: 1519 fib6_info_release(rt); 1520 if (neigh) 1521 neigh_release(neigh); 1522 } 1523 1524 static void ndisc_redirect_rcv(struct sk_buff *skb) 1525 { 1526 u8 *hdr; 1527 struct ndisc_options ndopts; 1528 struct rd_msg *msg = (struct rd_msg *)skb_transport_header(skb); 1529 u32 ndoptlen = skb_tail_pointer(skb) - (skb_transport_header(skb) + 1530 offsetof(struct rd_msg, opt)); 1531 1532 #ifdef CONFIG_IPV6_NDISC_NODETYPE 1533 switch (skb->ndisc_nodetype) { 1534 case NDISC_NODETYPE_HOST: 1535 case NDISC_NODETYPE_NODEFAULT: 1536 ND_PRINTK(2, warn, 1537 "Redirect: from host or unauthorized router\n"); 1538 return; 1539 } 1540 #endif 1541 1542 if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) { 1543 ND_PRINTK(2, warn, 1544 "Redirect: source address is not link-local\n"); 1545 return; 1546 } 1547 1548 if (!ndisc_parse_options(skb->dev, msg->opt, ndoptlen, &ndopts)) 1549 return; 1550 1551 if (!ndopts.nd_opts_rh) { 1552 ip6_redirect_no_header(skb, dev_net(skb->dev), 1553 skb->dev->ifindex); 1554 return; 1555 } 1556 1557 hdr = (u8 *)ndopts.nd_opts_rh; 1558 hdr += 8; 1559 if (!pskb_pull(skb, hdr - skb_transport_header(skb))) 1560 return; 1561 1562 icmpv6_notify(skb, NDISC_REDIRECT, 0, 0); 1563 } 1564 1565 static void ndisc_fill_redirect_hdr_option(struct sk_buff *skb, 1566 struct sk_buff *orig_skb, 1567 int rd_len) 1568 { 1569 u8 *opt = skb_put(skb, rd_len); 1570 1571 memset(opt, 0, 8); 1572 *(opt++) = ND_OPT_REDIRECT_HDR; 1573 *(opt++) = (rd_len >> 3); 1574 opt += 6; 1575 1576 skb_copy_bits(orig_skb, skb_network_offset(orig_skb), opt, 1577 rd_len - 8); 1578 } 1579 1580 void ndisc_send_redirect(struct sk_buff *skb, const struct in6_addr *target) 1581 { 1582 struct net_device *dev = skb->dev; 1583 struct net *net = dev_net(dev); 1584 struct sock *sk = net->ipv6.ndisc_sk; 1585 int optlen = 0; 1586 struct inet_peer *peer; 1587 struct sk_buff *buff; 1588 struct rd_msg *msg; 1589 struct in6_addr saddr_buf; 1590 struct rt6_info *rt; 1591 struct dst_entry *dst; 1592 struct flowi6 fl6; 1593 int rd_len; 1594 u8 ha_buf[MAX_ADDR_LEN], *ha = NULL, 1595 ops_data_buf[NDISC_OPS_REDIRECT_DATA_SPACE], *ops_data = NULL; 1596 bool ret; 1597 1598 if (netif_is_l3_master(skb->dev)) { 1599 dev = __dev_get_by_index(dev_net(skb->dev), IPCB(skb)->iif); 1600 if (!dev) 1601 return; 1602 } 1603 1604 if (ipv6_get_lladdr(dev, &saddr_buf, IFA_F_TENTATIVE)) { 1605 ND_PRINTK(2, warn, "Redirect: no link-local address on %s\n", 1606 dev->name); 1607 return; 1608 } 1609 1610 if (!ipv6_addr_equal(&ipv6_hdr(skb)->daddr, target) && 1611 ipv6_addr_type(target) != (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) { 1612 ND_PRINTK(2, warn, 1613 "Redirect: target address is not link-local unicast\n"); 1614 return; 1615 } 1616 1617 icmpv6_flow_init(sk, &fl6, NDISC_REDIRECT, 1618 &saddr_buf, &ipv6_hdr(skb)->saddr, dev->ifindex); 1619 1620 dst = ip6_route_output(net, NULL, &fl6); 1621 if (dst->error) { 1622 dst_release(dst); 1623 return; 1624 } 1625 dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), NULL, 0); 1626 if (IS_ERR(dst)) 1627 return; 1628 1629 rt = (struct rt6_info *) dst; 1630 1631 if (rt->rt6i_flags & RTF_GATEWAY) { 1632 ND_PRINTK(2, warn, 1633 "Redirect: destination is not a neighbour\n"); 1634 goto release; 1635 } 1636 peer = inet_getpeer_v6(net->ipv6.peers, &ipv6_hdr(skb)->saddr, 1); 1637 ret = inet_peer_xrlim_allow(peer, 1*HZ); 1638 if (peer) 1639 inet_putpeer(peer); 1640 if (!ret) 1641 goto release; 1642 1643 if (dev->addr_len) { 1644 struct neighbour *neigh = dst_neigh_lookup(skb_dst(skb), target); 1645 if (!neigh) { 1646 ND_PRINTK(2, warn, 1647 "Redirect: no neigh for target address\n"); 1648 goto release; 1649 } 1650 1651 read_lock_bh(&neigh->lock); 1652 if (neigh->nud_state & NUD_VALID) { 1653 memcpy(ha_buf, neigh->ha, dev->addr_len); 1654 read_unlock_bh(&neigh->lock); 1655 ha = ha_buf; 1656 optlen += ndisc_redirect_opt_addr_space(dev, neigh, 1657 ops_data_buf, 1658 &ops_data); 1659 } else 1660 read_unlock_bh(&neigh->lock); 1661 1662 neigh_release(neigh); 1663 } 1664 1665 rd_len = min_t(unsigned int, 1666 IPV6_MIN_MTU - sizeof(struct ipv6hdr) - sizeof(*msg) - optlen, 1667 skb->len + 8); 1668 rd_len &= ~0x7; 1669 optlen += rd_len; 1670 1671 buff = ndisc_alloc_skb(dev, sizeof(*msg) + optlen); 1672 if (!buff) 1673 goto release; 1674 1675 msg = skb_put(buff, sizeof(*msg)); 1676 *msg = (struct rd_msg) { 1677 .icmph = { 1678 .icmp6_type = NDISC_REDIRECT, 1679 }, 1680 .target = *target, 1681 .dest = ipv6_hdr(skb)->daddr, 1682 }; 1683 1684 /* 1685 * include target_address option 1686 */ 1687 1688 if (ha) 1689 ndisc_fill_redirect_addr_option(buff, ha, ops_data); 1690 1691 /* 1692 * build redirect option and copy skb over to the new packet. 1693 */ 1694 1695 if (rd_len) 1696 ndisc_fill_redirect_hdr_option(buff, skb, rd_len); 1697 1698 skb_dst_set(buff, dst); 1699 ndisc_send_skb(buff, &ipv6_hdr(skb)->saddr, &saddr_buf); 1700 return; 1701 1702 release: 1703 dst_release(dst); 1704 } 1705 1706 static void pndisc_redo(struct sk_buff *skb) 1707 { 1708 ndisc_recv_ns(skb); 1709 kfree_skb(skb); 1710 } 1711 1712 static bool ndisc_suppress_frag_ndisc(struct sk_buff *skb) 1713 { 1714 struct inet6_dev *idev = __in6_dev_get(skb->dev); 1715 1716 if (!idev) 1717 return true; 1718 if (IP6CB(skb)->flags & IP6SKB_FRAGMENTED && 1719 idev->cnf.suppress_frag_ndisc) { 1720 net_warn_ratelimited("Received fragmented ndisc packet. Carefully consider disabling suppress_frag_ndisc.\n"); 1721 return true; 1722 } 1723 return false; 1724 } 1725 1726 int ndisc_rcv(struct sk_buff *skb) 1727 { 1728 struct nd_msg *msg; 1729 1730 if (ndisc_suppress_frag_ndisc(skb)) 1731 return 0; 1732 1733 if (skb_linearize(skb)) 1734 return 0; 1735 1736 msg = (struct nd_msg *)skb_transport_header(skb); 1737 1738 __skb_push(skb, skb->data - skb_transport_header(skb)); 1739 1740 if (ipv6_hdr(skb)->hop_limit != 255) { 1741 ND_PRINTK(2, warn, "NDISC: invalid hop-limit: %d\n", 1742 ipv6_hdr(skb)->hop_limit); 1743 return 0; 1744 } 1745 1746 if (msg->icmph.icmp6_code != 0) { 1747 ND_PRINTK(2, warn, "NDISC: invalid ICMPv6 code: %d\n", 1748 msg->icmph.icmp6_code); 1749 return 0; 1750 } 1751 1752 switch (msg->icmph.icmp6_type) { 1753 case NDISC_NEIGHBOUR_SOLICITATION: 1754 memset(NEIGH_CB(skb), 0, sizeof(struct neighbour_cb)); 1755 ndisc_recv_ns(skb); 1756 break; 1757 1758 case NDISC_NEIGHBOUR_ADVERTISEMENT: 1759 ndisc_recv_na(skb); 1760 break; 1761 1762 case NDISC_ROUTER_SOLICITATION: 1763 ndisc_recv_rs(skb); 1764 break; 1765 1766 case NDISC_ROUTER_ADVERTISEMENT: 1767 ndisc_router_discovery(skb); 1768 break; 1769 1770 case NDISC_REDIRECT: 1771 ndisc_redirect_rcv(skb); 1772 break; 1773 } 1774 1775 return 0; 1776 } 1777 1778 static int ndisc_netdev_event(struct notifier_block *this, unsigned long event, void *ptr) 1779 { 1780 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 1781 struct netdev_notifier_change_info *change_info; 1782 struct net *net = dev_net(dev); 1783 struct inet6_dev *idev; 1784 1785 switch (event) { 1786 case NETDEV_CHANGEADDR: 1787 neigh_changeaddr(&nd_tbl, dev); 1788 fib6_run_gc(0, net, false); 1789 /* fallthrough */ 1790 case NETDEV_UP: 1791 idev = in6_dev_get(dev); 1792 if (!idev) 1793 break; 1794 if (idev->cnf.ndisc_notify || 1795 net->ipv6.devconf_all->ndisc_notify) 1796 ndisc_send_unsol_na(dev); 1797 in6_dev_put(idev); 1798 break; 1799 case NETDEV_CHANGE: 1800 change_info = ptr; 1801 if (change_info->flags_changed & IFF_NOARP) 1802 neigh_changeaddr(&nd_tbl, dev); 1803 if (!netif_carrier_ok(dev)) 1804 neigh_carrier_down(&nd_tbl, dev); 1805 break; 1806 case NETDEV_DOWN: 1807 neigh_ifdown(&nd_tbl, dev); 1808 fib6_run_gc(0, net, false); 1809 break; 1810 case NETDEV_NOTIFY_PEERS: 1811 ndisc_send_unsol_na(dev); 1812 break; 1813 default: 1814 break; 1815 } 1816 1817 return NOTIFY_DONE; 1818 } 1819 1820 static struct notifier_block ndisc_netdev_notifier = { 1821 .notifier_call = ndisc_netdev_event, 1822 .priority = ADDRCONF_NOTIFY_PRIORITY - 5, 1823 }; 1824 1825 #ifdef CONFIG_SYSCTL 1826 static void ndisc_warn_deprecated_sysctl(struct ctl_table *ctl, 1827 const char *func, const char *dev_name) 1828 { 1829 static char warncomm[TASK_COMM_LEN]; 1830 static int warned; 1831 if (strcmp(warncomm, current->comm) && warned < 5) { 1832 strcpy(warncomm, current->comm); 1833 pr_warn("process `%s' is using deprecated sysctl (%s) net.ipv6.neigh.%s.%s - use net.ipv6.neigh.%s.%s_ms instead\n", 1834 warncomm, func, 1835 dev_name, ctl->procname, 1836 dev_name, ctl->procname); 1837 warned++; 1838 } 1839 } 1840 1841 int ndisc_ifinfo_sysctl_change(struct ctl_table *ctl, int write, void __user *buffer, size_t *lenp, loff_t *ppos) 1842 { 1843 struct net_device *dev = ctl->extra1; 1844 struct inet6_dev *idev; 1845 int ret; 1846 1847 if ((strcmp(ctl->procname, "retrans_time") == 0) || 1848 (strcmp(ctl->procname, "base_reachable_time") == 0)) 1849 ndisc_warn_deprecated_sysctl(ctl, "syscall", dev ? dev->name : "default"); 1850 1851 if (strcmp(ctl->procname, "retrans_time") == 0) 1852 ret = neigh_proc_dointvec(ctl, write, buffer, lenp, ppos); 1853 1854 else if (strcmp(ctl->procname, "base_reachable_time") == 0) 1855 ret = neigh_proc_dointvec_jiffies(ctl, write, 1856 buffer, lenp, ppos); 1857 1858 else if ((strcmp(ctl->procname, "retrans_time_ms") == 0) || 1859 (strcmp(ctl->procname, "base_reachable_time_ms") == 0)) 1860 ret = neigh_proc_dointvec_ms_jiffies(ctl, write, 1861 buffer, lenp, ppos); 1862 else 1863 ret = -1; 1864 1865 if (write && ret == 0 && dev && (idev = in6_dev_get(dev)) != NULL) { 1866 if (ctl->data == &NEIGH_VAR(idev->nd_parms, BASE_REACHABLE_TIME)) 1867 idev->nd_parms->reachable_time = 1868 neigh_rand_reach_time(NEIGH_VAR(idev->nd_parms, BASE_REACHABLE_TIME)); 1869 idev->tstamp = jiffies; 1870 inet6_ifinfo_notify(RTM_NEWLINK, idev); 1871 in6_dev_put(idev); 1872 } 1873 return ret; 1874 } 1875 1876 1877 #endif 1878 1879 static int __net_init ndisc_net_init(struct net *net) 1880 { 1881 struct ipv6_pinfo *np; 1882 struct sock *sk; 1883 int err; 1884 1885 err = inet_ctl_sock_create(&sk, PF_INET6, 1886 SOCK_RAW, IPPROTO_ICMPV6, net); 1887 if (err < 0) { 1888 ND_PRINTK(0, err, 1889 "NDISC: Failed to initialize the control socket (err %d)\n", 1890 err); 1891 return err; 1892 } 1893 1894 net->ipv6.ndisc_sk = sk; 1895 1896 np = inet6_sk(sk); 1897 np->hop_limit = 255; 1898 /* Do not loopback ndisc messages */ 1899 np->mc_loop = 0; 1900 1901 return 0; 1902 } 1903 1904 static void __net_exit ndisc_net_exit(struct net *net) 1905 { 1906 inet_ctl_sock_destroy(net->ipv6.ndisc_sk); 1907 } 1908 1909 static struct pernet_operations ndisc_net_ops = { 1910 .init = ndisc_net_init, 1911 .exit = ndisc_net_exit, 1912 }; 1913 1914 int __init ndisc_init(void) 1915 { 1916 int err; 1917 1918 err = register_pernet_subsys(&ndisc_net_ops); 1919 if (err) 1920 return err; 1921 /* 1922 * Initialize the neighbour table 1923 */ 1924 neigh_table_init(NEIGH_ND_TABLE, &nd_tbl); 1925 1926 #ifdef CONFIG_SYSCTL 1927 err = neigh_sysctl_register(NULL, &nd_tbl.parms, 1928 ndisc_ifinfo_sysctl_change); 1929 if (err) 1930 goto out_unregister_pernet; 1931 out: 1932 #endif 1933 return err; 1934 1935 #ifdef CONFIG_SYSCTL 1936 out_unregister_pernet: 1937 unregister_pernet_subsys(&ndisc_net_ops); 1938 goto out; 1939 #endif 1940 } 1941 1942 int __init ndisc_late_init(void) 1943 { 1944 return register_netdevice_notifier(&ndisc_netdev_notifier); 1945 } 1946 1947 void ndisc_late_cleanup(void) 1948 { 1949 unregister_netdevice_notifier(&ndisc_netdev_notifier); 1950 } 1951 1952 void ndisc_cleanup(void) 1953 { 1954 #ifdef CONFIG_SYSCTL 1955 neigh_sysctl_unregister(&nd_tbl.parms); 1956 #endif 1957 neigh_table_clear(NEIGH_ND_TABLE, &nd_tbl); 1958 unregister_pernet_subsys(&ndisc_net_ops); 1959 } 1960