1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Neighbour Discovery for IPv6 4 * Linux INET6 implementation 5 * 6 * Authors: 7 * Pedro Roque <roque@di.fc.ul.pt> 8 * Mike Shaver <shaver@ingenia.com> 9 */ 10 11 /* 12 * Changes: 13 * 14 * Alexey I. Froloff : RFC6106 (DNSSL) support 15 * Pierre Ynard : export userland ND options 16 * through netlink (RDNSS support) 17 * Lars Fenneberg : fixed MTU setting on receipt 18 * of an RA. 19 * Janos Farkas : kmalloc failure checks 20 * Alexey Kuznetsov : state machine reworked 21 * and moved to net/core. 22 * Pekka Savola : RFC2461 validation 23 * YOSHIFUJI Hideaki @USAGI : Verify ND options properly 24 */ 25 26 #define pr_fmt(fmt) "ICMPv6: " fmt 27 28 #include <linux/module.h> 29 #include <linux/errno.h> 30 #include <linux/types.h> 31 #include <linux/socket.h> 32 #include <linux/sockios.h> 33 #include <linux/sched.h> 34 #include <linux/net.h> 35 #include <linux/in6.h> 36 #include <linux/route.h> 37 #include <linux/init.h> 38 #include <linux/rcupdate.h> 39 #include <linux/slab.h> 40 #ifdef CONFIG_SYSCTL 41 #include <linux/sysctl.h> 42 #endif 43 44 #include <linux/if_addr.h> 45 #include <linux/if_ether.h> 46 #include <linux/if_arp.h> 47 #include <linux/ipv6.h> 48 #include <linux/icmpv6.h> 49 #include <linux/jhash.h> 50 51 #include <net/sock.h> 52 #include <net/snmp.h> 53 54 #include <net/ipv6.h> 55 #include <net/protocol.h> 56 #include <net/ndisc.h> 57 #include <net/ip6_route.h> 58 #include <net/addrconf.h> 59 #include <net/icmp.h> 60 61 #include <net/netlink.h> 62 #include <linux/rtnetlink.h> 63 64 #include <net/flow.h> 65 #include <net/ip6_checksum.h> 66 #include <net/inet_common.h> 67 #include <linux/proc_fs.h> 68 69 #include <linux/netfilter.h> 70 #include <linux/netfilter_ipv6.h> 71 72 static u32 ndisc_hash(const void *pkey, 73 const struct net_device *dev, 74 __u32 *hash_rnd); 75 static bool ndisc_key_eq(const struct neighbour *neigh, const void *pkey); 76 static bool ndisc_allow_add(const struct net_device *dev, 77 struct netlink_ext_ack *extack); 78 static int ndisc_constructor(struct neighbour *neigh); 79 static void ndisc_solicit(struct neighbour *neigh, struct sk_buff *skb); 80 static void ndisc_error_report(struct neighbour *neigh, struct sk_buff *skb); 81 static int pndisc_constructor(struct pneigh_entry *n); 82 static void pndisc_destructor(struct pneigh_entry *n); 83 static void pndisc_redo(struct sk_buff *skb); 84 static int ndisc_is_multicast(const void *pkey); 85 86 static const struct neigh_ops ndisc_generic_ops = { 87 .family = AF_INET6, 88 .solicit = ndisc_solicit, 89 .error_report = ndisc_error_report, 90 .output = neigh_resolve_output, 91 .connected_output = neigh_connected_output, 92 }; 93 94 static const struct neigh_ops ndisc_hh_ops = { 95 .family = AF_INET6, 96 .solicit = ndisc_solicit, 97 .error_report = ndisc_error_report, 98 .output = neigh_resolve_output, 99 .connected_output = neigh_resolve_output, 100 }; 101 102 103 static const struct neigh_ops ndisc_direct_ops = { 104 .family = AF_INET6, 105 .output = neigh_direct_output, 106 .connected_output = neigh_direct_output, 107 }; 108 109 struct neigh_table nd_tbl = { 110 .family = AF_INET6, 111 .key_len = sizeof(struct in6_addr), 112 .protocol = cpu_to_be16(ETH_P_IPV6), 113 .hash = ndisc_hash, 114 .key_eq = ndisc_key_eq, 115 .constructor = ndisc_constructor, 116 .pconstructor = pndisc_constructor, 117 .pdestructor = pndisc_destructor, 118 .proxy_redo = pndisc_redo, 119 .is_multicast = ndisc_is_multicast, 120 .allow_add = ndisc_allow_add, 121 .id = "ndisc_cache", 122 .parms = { 123 .tbl = &nd_tbl, 124 .reachable_time = ND_REACHABLE_TIME, 125 .data = { 126 [NEIGH_VAR_MCAST_PROBES] = 3, 127 [NEIGH_VAR_UCAST_PROBES] = 3, 128 [NEIGH_VAR_RETRANS_TIME] = ND_RETRANS_TIMER, 129 [NEIGH_VAR_BASE_REACHABLE_TIME] = ND_REACHABLE_TIME, 130 [NEIGH_VAR_DELAY_PROBE_TIME] = 5 * HZ, 131 [NEIGH_VAR_INTERVAL_PROBE_TIME_MS] = 5 * HZ, 132 [NEIGH_VAR_GC_STALETIME] = 60 * HZ, 133 [NEIGH_VAR_QUEUE_LEN_BYTES] = SK_WMEM_MAX, 134 [NEIGH_VAR_PROXY_QLEN] = 64, 135 [NEIGH_VAR_ANYCAST_DELAY] = 1 * HZ, 136 [NEIGH_VAR_PROXY_DELAY] = (8 * HZ) / 10, 137 }, 138 }, 139 .gc_interval = 30 * HZ, 140 .gc_thresh1 = 128, 141 .gc_thresh2 = 512, 142 .gc_thresh3 = 1024, 143 }; 144 EXPORT_SYMBOL_GPL(nd_tbl); 145 146 void __ndisc_fill_addr_option(struct sk_buff *skb, int type, const void *data, 147 int data_len, int pad) 148 { 149 int space = __ndisc_opt_addr_space(data_len, pad); 150 u8 *opt = skb_put(skb, space); 151 152 opt[0] = type; 153 opt[1] = space>>3; 154 155 memset(opt + 2, 0, pad); 156 opt += pad; 157 space -= pad; 158 159 memcpy(opt+2, data, data_len); 160 data_len += 2; 161 opt += data_len; 162 space -= data_len; 163 if (space > 0) 164 memset(opt, 0, space); 165 } 166 EXPORT_SYMBOL_GPL(__ndisc_fill_addr_option); 167 168 static inline void ndisc_fill_addr_option(struct sk_buff *skb, int type, 169 const void *data, u8 icmp6_type) 170 { 171 __ndisc_fill_addr_option(skb, type, data, skb->dev->addr_len, 172 ndisc_addr_option_pad(skb->dev->type)); 173 ndisc_ops_fill_addr_option(skb->dev, skb, icmp6_type); 174 } 175 176 static inline void ndisc_fill_redirect_addr_option(struct sk_buff *skb, 177 void *ha, 178 const u8 *ops_data) 179 { 180 ndisc_fill_addr_option(skb, ND_OPT_TARGET_LL_ADDR, ha, NDISC_REDIRECT); 181 ndisc_ops_fill_redirect_addr_option(skb->dev, skb, ops_data); 182 } 183 184 static struct nd_opt_hdr *ndisc_next_option(struct nd_opt_hdr *cur, 185 struct nd_opt_hdr *end) 186 { 187 int type; 188 if (!cur || !end || cur >= end) 189 return NULL; 190 type = cur->nd_opt_type; 191 do { 192 cur = ((void *)cur) + (cur->nd_opt_len << 3); 193 } while (cur < end && cur->nd_opt_type != type); 194 return cur <= end && cur->nd_opt_type == type ? cur : NULL; 195 } 196 197 static inline int ndisc_is_useropt(const struct net_device *dev, 198 struct nd_opt_hdr *opt) 199 { 200 return opt->nd_opt_type == ND_OPT_RDNSS || 201 opt->nd_opt_type == ND_OPT_DNSSL || 202 opt->nd_opt_type == ND_OPT_CAPTIVE_PORTAL || 203 opt->nd_opt_type == ND_OPT_PREF64 || 204 ndisc_ops_is_useropt(dev, opt->nd_opt_type); 205 } 206 207 static struct nd_opt_hdr *ndisc_next_useropt(const struct net_device *dev, 208 struct nd_opt_hdr *cur, 209 struct nd_opt_hdr *end) 210 { 211 if (!cur || !end || cur >= end) 212 return NULL; 213 do { 214 cur = ((void *)cur) + (cur->nd_opt_len << 3); 215 } while (cur < end && !ndisc_is_useropt(dev, cur)); 216 return cur <= end && ndisc_is_useropt(dev, cur) ? cur : NULL; 217 } 218 219 struct ndisc_options *ndisc_parse_options(const struct net_device *dev, 220 u8 *opt, int opt_len, 221 struct ndisc_options *ndopts) 222 { 223 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)opt; 224 225 if (!nd_opt || opt_len < 0 || !ndopts) 226 return NULL; 227 memset(ndopts, 0, sizeof(*ndopts)); 228 while (opt_len) { 229 int l; 230 if (opt_len < sizeof(struct nd_opt_hdr)) 231 return NULL; 232 l = nd_opt->nd_opt_len << 3; 233 if (opt_len < l || l == 0) 234 return NULL; 235 if (ndisc_ops_parse_options(dev, nd_opt, ndopts)) 236 goto next_opt; 237 switch (nd_opt->nd_opt_type) { 238 case ND_OPT_SOURCE_LL_ADDR: 239 case ND_OPT_TARGET_LL_ADDR: 240 case ND_OPT_MTU: 241 case ND_OPT_NONCE: 242 case ND_OPT_REDIRECT_HDR: 243 if (ndopts->nd_opt_array[nd_opt->nd_opt_type]) { 244 ND_PRINTK(2, warn, 245 "%s: duplicated ND6 option found: type=%d\n", 246 __func__, nd_opt->nd_opt_type); 247 } else { 248 ndopts->nd_opt_array[nd_opt->nd_opt_type] = nd_opt; 249 } 250 break; 251 case ND_OPT_PREFIX_INFO: 252 ndopts->nd_opts_pi_end = nd_opt; 253 if (!ndopts->nd_opt_array[nd_opt->nd_opt_type]) 254 ndopts->nd_opt_array[nd_opt->nd_opt_type] = nd_opt; 255 break; 256 #ifdef CONFIG_IPV6_ROUTE_INFO 257 case ND_OPT_ROUTE_INFO: 258 ndopts->nd_opts_ri_end = nd_opt; 259 if (!ndopts->nd_opts_ri) 260 ndopts->nd_opts_ri = nd_opt; 261 break; 262 #endif 263 default: 264 if (ndisc_is_useropt(dev, nd_opt)) { 265 ndopts->nd_useropts_end = nd_opt; 266 if (!ndopts->nd_useropts) 267 ndopts->nd_useropts = nd_opt; 268 } else { 269 /* 270 * Unknown options must be silently ignored, 271 * to accommodate future extension to the 272 * protocol. 273 */ 274 ND_PRINTK(2, notice, 275 "%s: ignored unsupported option; type=%d, len=%d\n", 276 __func__, 277 nd_opt->nd_opt_type, 278 nd_opt->nd_opt_len); 279 } 280 } 281 next_opt: 282 opt_len -= l; 283 nd_opt = ((void *)nd_opt) + l; 284 } 285 return ndopts; 286 } 287 288 int ndisc_mc_map(const struct in6_addr *addr, char *buf, struct net_device *dev, int dir) 289 { 290 switch (dev->type) { 291 case ARPHRD_ETHER: 292 case ARPHRD_IEEE802: /* Not sure. Check it later. --ANK */ 293 case ARPHRD_FDDI: 294 ipv6_eth_mc_map(addr, buf); 295 return 0; 296 case ARPHRD_ARCNET: 297 ipv6_arcnet_mc_map(addr, buf); 298 return 0; 299 case ARPHRD_INFINIBAND: 300 ipv6_ib_mc_map(addr, dev->broadcast, buf); 301 return 0; 302 case ARPHRD_IPGRE: 303 return ipv6_ipgre_mc_map(addr, dev->broadcast, buf); 304 default: 305 if (dir) { 306 memcpy(buf, dev->broadcast, dev->addr_len); 307 return 0; 308 } 309 } 310 return -EINVAL; 311 } 312 EXPORT_SYMBOL(ndisc_mc_map); 313 314 static u32 ndisc_hash(const void *pkey, 315 const struct net_device *dev, 316 __u32 *hash_rnd) 317 { 318 return ndisc_hashfn(pkey, dev, hash_rnd); 319 } 320 321 static bool ndisc_key_eq(const struct neighbour *n, const void *pkey) 322 { 323 return neigh_key_eq128(n, pkey); 324 } 325 326 static int ndisc_constructor(struct neighbour *neigh) 327 { 328 struct in6_addr *addr = (struct in6_addr *)&neigh->primary_key; 329 struct net_device *dev = neigh->dev; 330 struct inet6_dev *in6_dev; 331 struct neigh_parms *parms; 332 bool is_multicast = ipv6_addr_is_multicast(addr); 333 334 in6_dev = in6_dev_get(dev); 335 if (!in6_dev) { 336 return -EINVAL; 337 } 338 339 parms = in6_dev->nd_parms; 340 __neigh_parms_put(neigh->parms); 341 neigh->parms = neigh_parms_clone(parms); 342 343 neigh->type = is_multicast ? RTN_MULTICAST : RTN_UNICAST; 344 if (!dev->header_ops) { 345 neigh->nud_state = NUD_NOARP; 346 neigh->ops = &ndisc_direct_ops; 347 neigh->output = neigh_direct_output; 348 } else { 349 if (is_multicast) { 350 neigh->nud_state = NUD_NOARP; 351 ndisc_mc_map(addr, neigh->ha, dev, 1); 352 } else if (dev->flags&(IFF_NOARP|IFF_LOOPBACK)) { 353 neigh->nud_state = NUD_NOARP; 354 memcpy(neigh->ha, dev->dev_addr, dev->addr_len); 355 if (dev->flags&IFF_LOOPBACK) 356 neigh->type = RTN_LOCAL; 357 } else if (dev->flags&IFF_POINTOPOINT) { 358 neigh->nud_state = NUD_NOARP; 359 memcpy(neigh->ha, dev->broadcast, dev->addr_len); 360 } 361 if (dev->header_ops->cache) 362 neigh->ops = &ndisc_hh_ops; 363 else 364 neigh->ops = &ndisc_generic_ops; 365 if (neigh->nud_state&NUD_VALID) 366 neigh->output = neigh->ops->connected_output; 367 else 368 neigh->output = neigh->ops->output; 369 } 370 in6_dev_put(in6_dev); 371 return 0; 372 } 373 374 static int pndisc_constructor(struct pneigh_entry *n) 375 { 376 struct in6_addr *addr = (struct in6_addr *)&n->key; 377 struct in6_addr maddr; 378 struct net_device *dev = n->dev; 379 380 if (!dev || !__in6_dev_get(dev)) 381 return -EINVAL; 382 addrconf_addr_solict_mult(addr, &maddr); 383 ipv6_dev_mc_inc(dev, &maddr); 384 return 0; 385 } 386 387 static void pndisc_destructor(struct pneigh_entry *n) 388 { 389 struct in6_addr *addr = (struct in6_addr *)&n->key; 390 struct in6_addr maddr; 391 struct net_device *dev = n->dev; 392 393 if (!dev || !__in6_dev_get(dev)) 394 return; 395 addrconf_addr_solict_mult(addr, &maddr); 396 ipv6_dev_mc_dec(dev, &maddr); 397 } 398 399 /* called with rtnl held */ 400 static bool ndisc_allow_add(const struct net_device *dev, 401 struct netlink_ext_ack *extack) 402 { 403 struct inet6_dev *idev = __in6_dev_get(dev); 404 405 if (!idev || idev->cnf.disable_ipv6) { 406 NL_SET_ERR_MSG(extack, "IPv6 is disabled on this device"); 407 return false; 408 } 409 410 return true; 411 } 412 413 static struct sk_buff *ndisc_alloc_skb(struct net_device *dev, 414 int len) 415 { 416 int hlen = LL_RESERVED_SPACE(dev); 417 int tlen = dev->needed_tailroom; 418 struct sock *sk = dev_net(dev)->ipv6.ndisc_sk; 419 struct sk_buff *skb; 420 421 skb = alloc_skb(hlen + sizeof(struct ipv6hdr) + len + tlen, GFP_ATOMIC); 422 if (!skb) { 423 ND_PRINTK(0, err, "ndisc: %s failed to allocate an skb\n", 424 __func__); 425 return NULL; 426 } 427 428 skb->protocol = htons(ETH_P_IPV6); 429 skb->dev = dev; 430 431 skb_reserve(skb, hlen + sizeof(struct ipv6hdr)); 432 skb_reset_transport_header(skb); 433 434 /* Manually assign socket ownership as we avoid calling 435 * sock_alloc_send_pskb() to bypass wmem buffer limits 436 */ 437 skb_set_owner_w(skb, sk); 438 439 return skb; 440 } 441 442 static void ip6_nd_hdr(struct sk_buff *skb, 443 const struct in6_addr *saddr, 444 const struct in6_addr *daddr, 445 int hop_limit, int len) 446 { 447 struct ipv6hdr *hdr; 448 struct inet6_dev *idev; 449 unsigned tclass; 450 451 rcu_read_lock(); 452 idev = __in6_dev_get(skb->dev); 453 tclass = idev ? idev->cnf.ndisc_tclass : 0; 454 rcu_read_unlock(); 455 456 skb_push(skb, sizeof(*hdr)); 457 skb_reset_network_header(skb); 458 hdr = ipv6_hdr(skb); 459 460 ip6_flow_hdr(hdr, tclass, 0); 461 462 hdr->payload_len = htons(len); 463 hdr->nexthdr = IPPROTO_ICMPV6; 464 hdr->hop_limit = hop_limit; 465 466 hdr->saddr = *saddr; 467 hdr->daddr = *daddr; 468 } 469 470 void ndisc_send_skb(struct sk_buff *skb, 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 EXPORT_SYMBOL(ndisc_send_skb); 519 520 void ndisc_send_na(struct net_device *dev, const struct in6_addr *daddr, 521 const struct in6_addr *solicited_addr, 522 bool router, bool solicited, bool override, bool inc_opt) 523 { 524 struct sk_buff *skb; 525 struct in6_addr tmpaddr; 526 struct inet6_ifaddr *ifp; 527 const struct in6_addr *src_addr; 528 struct nd_msg *msg; 529 int optlen = 0; 530 531 /* for anycast or proxy, solicited_addr != src_addr */ 532 ifp = ipv6_get_ifaddr(dev_net(dev), solicited_addr, dev, 1); 533 if (ifp) { 534 src_addr = solicited_addr; 535 if (ifp->flags & IFA_F_OPTIMISTIC) 536 override = false; 537 inc_opt |= ifp->idev->cnf.force_tllao; 538 in6_ifa_put(ifp); 539 } else { 540 if (ipv6_dev_get_saddr(dev_net(dev), dev, daddr, 541 inet6_sk(dev_net(dev)->ipv6.ndisc_sk)->srcprefs, 542 &tmpaddr)) 543 return; 544 src_addr = &tmpaddr; 545 } 546 547 if (!dev->addr_len) 548 inc_opt = false; 549 if (inc_opt) 550 optlen += ndisc_opt_addr_space(dev, 551 NDISC_NEIGHBOUR_ADVERTISEMENT); 552 553 skb = ndisc_alloc_skb(dev, sizeof(*msg) + optlen); 554 if (!skb) 555 return; 556 557 msg = skb_put(skb, sizeof(*msg)); 558 *msg = (struct nd_msg) { 559 .icmph = { 560 .icmp6_type = NDISC_NEIGHBOUR_ADVERTISEMENT, 561 .icmp6_router = router, 562 .icmp6_solicited = solicited, 563 .icmp6_override = override, 564 }, 565 .target = *solicited_addr, 566 }; 567 568 if (inc_opt) 569 ndisc_fill_addr_option(skb, ND_OPT_TARGET_LL_ADDR, 570 dev->dev_addr, 571 NDISC_NEIGHBOUR_ADVERTISEMENT); 572 573 ndisc_send_skb(skb, daddr, src_addr); 574 } 575 576 static void ndisc_send_unsol_na(struct net_device *dev) 577 { 578 struct inet6_dev *idev; 579 struct inet6_ifaddr *ifa; 580 581 idev = in6_dev_get(dev); 582 if (!idev) 583 return; 584 585 read_lock_bh(&idev->lock); 586 list_for_each_entry(ifa, &idev->addr_list, if_list) { 587 /* skip tentative addresses until dad completes */ 588 if (ifa->flags & IFA_F_TENTATIVE && 589 !(ifa->flags & IFA_F_OPTIMISTIC)) 590 continue; 591 592 ndisc_send_na(dev, &in6addr_linklocal_allnodes, &ifa->addr, 593 /*router=*/ !!idev->cnf.forwarding, 594 /*solicited=*/ false, /*override=*/ true, 595 /*inc_opt=*/ true); 596 } 597 read_unlock_bh(&idev->lock); 598 599 in6_dev_put(idev); 600 } 601 602 struct sk_buff *ndisc_ns_create(struct net_device *dev, const struct in6_addr *solicit, 603 const struct in6_addr *saddr, u64 nonce) 604 { 605 int inc_opt = dev->addr_len; 606 struct sk_buff *skb; 607 struct nd_msg *msg; 608 int optlen = 0; 609 610 if (!saddr) 611 return NULL; 612 613 if (ipv6_addr_any(saddr)) 614 inc_opt = false; 615 if (inc_opt) 616 optlen += ndisc_opt_addr_space(dev, 617 NDISC_NEIGHBOUR_SOLICITATION); 618 if (nonce != 0) 619 optlen += 8; 620 621 skb = ndisc_alloc_skb(dev, sizeof(*msg) + optlen); 622 if (!skb) 623 return NULL; 624 625 msg = skb_put(skb, sizeof(*msg)); 626 *msg = (struct nd_msg) { 627 .icmph = { 628 .icmp6_type = NDISC_NEIGHBOUR_SOLICITATION, 629 }, 630 .target = *solicit, 631 }; 632 633 if (inc_opt) 634 ndisc_fill_addr_option(skb, ND_OPT_SOURCE_LL_ADDR, 635 dev->dev_addr, 636 NDISC_NEIGHBOUR_SOLICITATION); 637 if (nonce != 0) { 638 u8 *opt = skb_put(skb, 8); 639 640 opt[0] = ND_OPT_NONCE; 641 opt[1] = 8 >> 3; 642 memcpy(opt + 2, &nonce, 6); 643 } 644 645 return skb; 646 } 647 EXPORT_SYMBOL(ndisc_ns_create); 648 649 void ndisc_send_ns(struct net_device *dev, const struct in6_addr *solicit, 650 const struct in6_addr *daddr, const struct in6_addr *saddr, 651 u64 nonce) 652 { 653 struct in6_addr addr_buf; 654 struct sk_buff *skb; 655 656 if (!saddr) { 657 if (ipv6_get_lladdr(dev, &addr_buf, 658 (IFA_F_TENTATIVE | IFA_F_OPTIMISTIC))) 659 return; 660 saddr = &addr_buf; 661 } 662 663 skb = ndisc_ns_create(dev, solicit, saddr, nonce); 664 665 if (skb) 666 ndisc_send_skb(skb, daddr, saddr); 667 } 668 669 void ndisc_send_rs(struct net_device *dev, const struct in6_addr *saddr, 670 const struct in6_addr *daddr) 671 { 672 struct sk_buff *skb; 673 struct rs_msg *msg; 674 int send_sllao = dev->addr_len; 675 int optlen = 0; 676 677 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD 678 /* 679 * According to section 2.2 of RFC 4429, we must not 680 * send router solicitations with a sllao from 681 * optimistic addresses, but we may send the solicitation 682 * if we don't include the sllao. So here we check 683 * if our address is optimistic, and if so, we 684 * suppress the inclusion of the sllao. 685 */ 686 if (send_sllao) { 687 struct inet6_ifaddr *ifp = ipv6_get_ifaddr(dev_net(dev), saddr, 688 dev, 1); 689 if (ifp) { 690 if (ifp->flags & IFA_F_OPTIMISTIC) { 691 send_sllao = 0; 692 } 693 in6_ifa_put(ifp); 694 } else { 695 send_sllao = 0; 696 } 697 } 698 #endif 699 if (send_sllao) 700 optlen += ndisc_opt_addr_space(dev, NDISC_ROUTER_SOLICITATION); 701 702 skb = ndisc_alloc_skb(dev, sizeof(*msg) + optlen); 703 if (!skb) 704 return; 705 706 msg = skb_put(skb, sizeof(*msg)); 707 *msg = (struct rs_msg) { 708 .icmph = { 709 .icmp6_type = NDISC_ROUTER_SOLICITATION, 710 }, 711 }; 712 713 if (send_sllao) 714 ndisc_fill_addr_option(skb, ND_OPT_SOURCE_LL_ADDR, 715 dev->dev_addr, 716 NDISC_ROUTER_SOLICITATION); 717 718 ndisc_send_skb(skb, daddr, saddr); 719 } 720 721 722 static void ndisc_error_report(struct neighbour *neigh, struct sk_buff *skb) 723 { 724 /* 725 * "The sender MUST return an ICMP 726 * destination unreachable" 727 */ 728 dst_link_failure(skb); 729 kfree_skb(skb); 730 } 731 732 /* Called with locked neigh: either read or both */ 733 734 static void ndisc_solicit(struct neighbour *neigh, struct sk_buff *skb) 735 { 736 struct in6_addr *saddr = NULL; 737 struct in6_addr mcaddr; 738 struct net_device *dev = neigh->dev; 739 struct in6_addr *target = (struct in6_addr *)&neigh->primary_key; 740 int probes = atomic_read(&neigh->probes); 741 742 if (skb && ipv6_chk_addr_and_flags(dev_net(dev), &ipv6_hdr(skb)->saddr, 743 dev, false, 1, 744 IFA_F_TENTATIVE|IFA_F_OPTIMISTIC)) 745 saddr = &ipv6_hdr(skb)->saddr; 746 probes -= NEIGH_VAR(neigh->parms, UCAST_PROBES); 747 if (probes < 0) { 748 if (!(neigh->nud_state & NUD_VALID)) { 749 ND_PRINTK(1, dbg, 750 "%s: trying to ucast probe in NUD_INVALID: %pI6\n", 751 __func__, target); 752 } 753 ndisc_send_ns(dev, target, target, saddr, 0); 754 } else if ((probes -= NEIGH_VAR(neigh->parms, APP_PROBES)) < 0) { 755 neigh_app_ns(neigh); 756 } else { 757 addrconf_addr_solict_mult(target, &mcaddr); 758 ndisc_send_ns(dev, target, &mcaddr, saddr, 0); 759 } 760 } 761 762 static int pndisc_is_router(const void *pkey, 763 struct net_device *dev) 764 { 765 struct pneigh_entry *n; 766 int ret = -1; 767 768 read_lock_bh(&nd_tbl.lock); 769 n = __pneigh_lookup(&nd_tbl, dev_net(dev), pkey, dev); 770 if (n) 771 ret = !!(n->flags & NTF_ROUTER); 772 read_unlock_bh(&nd_tbl.lock); 773 774 return ret; 775 } 776 777 void ndisc_update(const struct net_device *dev, struct neighbour *neigh, 778 const u8 *lladdr, u8 new, u32 flags, u8 icmp6_type, 779 struct ndisc_options *ndopts) 780 { 781 neigh_update(neigh, lladdr, new, flags, 0); 782 /* report ndisc ops about neighbour update */ 783 ndisc_ops_update(dev, neigh, flags, icmp6_type, ndopts); 784 } 785 786 static void ndisc_recv_ns(struct sk_buff *skb) 787 { 788 struct nd_msg *msg = (struct nd_msg *)skb_transport_header(skb); 789 const struct in6_addr *saddr = &ipv6_hdr(skb)->saddr; 790 const struct in6_addr *daddr = &ipv6_hdr(skb)->daddr; 791 u8 *lladdr = NULL; 792 u32 ndoptlen = skb_tail_pointer(skb) - (skb_transport_header(skb) + 793 offsetof(struct nd_msg, opt)); 794 struct ndisc_options ndopts; 795 struct net_device *dev = skb->dev; 796 struct inet6_ifaddr *ifp; 797 struct inet6_dev *idev = NULL; 798 struct neighbour *neigh; 799 int dad = ipv6_addr_any(saddr); 800 bool inc; 801 int is_router = -1; 802 u64 nonce = 0; 803 804 if (skb->len < sizeof(struct nd_msg)) { 805 ND_PRINTK(2, warn, "NS: packet too short\n"); 806 return; 807 } 808 809 if (ipv6_addr_is_multicast(&msg->target)) { 810 ND_PRINTK(2, warn, "NS: multicast target address\n"); 811 return; 812 } 813 814 /* 815 * RFC2461 7.1.1: 816 * DAD has to be destined for solicited node multicast address. 817 */ 818 if (dad && !ipv6_addr_is_solict_mult(daddr)) { 819 ND_PRINTK(2, warn, "NS: bad DAD packet (wrong destination)\n"); 820 return; 821 } 822 823 if (!ndisc_parse_options(dev, msg->opt, ndoptlen, &ndopts)) { 824 ND_PRINTK(2, warn, "NS: invalid ND options\n"); 825 return; 826 } 827 828 if (ndopts.nd_opts_src_lladdr) { 829 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr, dev); 830 if (!lladdr) { 831 ND_PRINTK(2, warn, 832 "NS: invalid link-layer address length\n"); 833 return; 834 } 835 836 /* RFC2461 7.1.1: 837 * If the IP source address is the unspecified address, 838 * there MUST NOT be source link-layer address option 839 * in the message. 840 */ 841 if (dad) { 842 ND_PRINTK(2, warn, 843 "NS: bad DAD packet (link-layer address option)\n"); 844 return; 845 } 846 } 847 if (ndopts.nd_opts_nonce && ndopts.nd_opts_nonce->nd_opt_len == 1) 848 memcpy(&nonce, (u8 *)(ndopts.nd_opts_nonce + 1), 6); 849 850 inc = ipv6_addr_is_multicast(daddr); 851 852 ifp = ipv6_get_ifaddr(dev_net(dev), &msg->target, dev, 1); 853 if (ifp) { 854 have_ifp: 855 if (ifp->flags & (IFA_F_TENTATIVE|IFA_F_OPTIMISTIC)) { 856 if (dad) { 857 if (nonce != 0 && ifp->dad_nonce == nonce) { 858 u8 *np = (u8 *)&nonce; 859 /* Matching nonce if looped back */ 860 ND_PRINTK(2, notice, 861 "%s: IPv6 DAD loopback for address %pI6c nonce %pM ignored\n", 862 ifp->idev->dev->name, 863 &ifp->addr, np); 864 goto out; 865 } 866 /* 867 * We are colliding with another node 868 * who is doing DAD 869 * so fail our DAD process 870 */ 871 addrconf_dad_failure(skb, ifp); 872 return; 873 } else { 874 /* 875 * This is not a dad solicitation. 876 * If we are an optimistic node, 877 * we should respond. 878 * Otherwise, we should ignore it. 879 */ 880 if (!(ifp->flags & IFA_F_OPTIMISTIC)) 881 goto out; 882 } 883 } 884 885 idev = ifp->idev; 886 } else { 887 struct net *net = dev_net(dev); 888 889 /* perhaps an address on the master device */ 890 if (netif_is_l3_slave(dev)) { 891 struct net_device *mdev; 892 893 mdev = netdev_master_upper_dev_get_rcu(dev); 894 if (mdev) { 895 ifp = ipv6_get_ifaddr(net, &msg->target, mdev, 1); 896 if (ifp) 897 goto have_ifp; 898 } 899 } 900 901 idev = in6_dev_get(dev); 902 if (!idev) { 903 /* XXX: count this drop? */ 904 return; 905 } 906 907 if (ipv6_chk_acast_addr(net, dev, &msg->target) || 908 (idev->cnf.forwarding && 909 (net->ipv6.devconf_all->proxy_ndp || idev->cnf.proxy_ndp) && 910 (is_router = pndisc_is_router(&msg->target, dev)) >= 0)) { 911 if (!(NEIGH_CB(skb)->flags & LOCALLY_ENQUEUED) && 912 skb->pkt_type != PACKET_HOST && 913 inc && 914 NEIGH_VAR(idev->nd_parms, PROXY_DELAY) != 0) { 915 /* 916 * for anycast or proxy, 917 * sender should delay its response 918 * by a random time between 0 and 919 * MAX_ANYCAST_DELAY_TIME seconds. 920 * (RFC2461) -- yoshfuji 921 */ 922 struct sk_buff *n = skb_clone(skb, GFP_ATOMIC); 923 if (n) 924 pneigh_enqueue(&nd_tbl, idev->nd_parms, n); 925 goto out; 926 } 927 } else 928 goto out; 929 } 930 931 if (is_router < 0) 932 is_router = idev->cnf.forwarding; 933 934 if (dad) { 935 ndisc_send_na(dev, &in6addr_linklocal_allnodes, &msg->target, 936 !!is_router, false, (ifp != NULL), true); 937 goto out; 938 } 939 940 if (inc) 941 NEIGH_CACHE_STAT_INC(&nd_tbl, rcv_probes_mcast); 942 else 943 NEIGH_CACHE_STAT_INC(&nd_tbl, rcv_probes_ucast); 944 945 /* 946 * update / create cache entry 947 * for the source address 948 */ 949 neigh = __neigh_lookup(&nd_tbl, saddr, dev, 950 !inc || lladdr || !dev->addr_len); 951 if (neigh) 952 ndisc_update(dev, neigh, lladdr, NUD_STALE, 953 NEIGH_UPDATE_F_WEAK_OVERRIDE| 954 NEIGH_UPDATE_F_OVERRIDE, 955 NDISC_NEIGHBOUR_SOLICITATION, &ndopts); 956 if (neigh || !dev->header_ops) { 957 ndisc_send_na(dev, saddr, &msg->target, !!is_router, 958 true, (ifp != NULL && inc), inc); 959 if (neigh) 960 neigh_release(neigh); 961 } 962 963 out: 964 if (ifp) 965 in6_ifa_put(ifp); 966 else 967 in6_dev_put(idev); 968 } 969 970 static int accept_untracked_na(struct net_device *dev, struct in6_addr *saddr) 971 { 972 struct inet6_dev *idev = __in6_dev_get(dev); 973 974 switch (idev->cnf.accept_untracked_na) { 975 case 0: /* Don't accept untracked na (absent in neighbor cache) */ 976 return 0; 977 case 1: /* Create new entries from na if currently untracked */ 978 return 1; 979 case 2: /* Create new entries from untracked na only if saddr is in the 980 * same subnet as an address configured on the interface that 981 * received the na 982 */ 983 return !!ipv6_chk_prefix(saddr, dev); 984 default: 985 return 0; 986 } 987 } 988 989 static void ndisc_recv_na(struct sk_buff *skb) 990 { 991 struct nd_msg *msg = (struct nd_msg *)skb_transport_header(skb); 992 struct in6_addr *saddr = &ipv6_hdr(skb)->saddr; 993 const struct in6_addr *daddr = &ipv6_hdr(skb)->daddr; 994 u8 *lladdr = NULL; 995 u32 ndoptlen = skb_tail_pointer(skb) - (skb_transport_header(skb) + 996 offsetof(struct nd_msg, opt)); 997 struct ndisc_options ndopts; 998 struct net_device *dev = skb->dev; 999 struct inet6_dev *idev = __in6_dev_get(dev); 1000 struct inet6_ifaddr *ifp; 1001 struct neighbour *neigh; 1002 u8 new_state; 1003 1004 if (skb->len < sizeof(struct nd_msg)) { 1005 ND_PRINTK(2, warn, "NA: packet too short\n"); 1006 return; 1007 } 1008 1009 if (ipv6_addr_is_multicast(&msg->target)) { 1010 ND_PRINTK(2, warn, "NA: target address is multicast\n"); 1011 return; 1012 } 1013 1014 if (ipv6_addr_is_multicast(daddr) && 1015 msg->icmph.icmp6_solicited) { 1016 ND_PRINTK(2, warn, "NA: solicited NA is multicasted\n"); 1017 return; 1018 } 1019 1020 /* For some 802.11 wireless deployments (and possibly other networks), 1021 * there will be a NA proxy and unsolicitd packets are attacks 1022 * and thus should not be accepted. 1023 * drop_unsolicited_na takes precedence over accept_untracked_na 1024 */ 1025 if (!msg->icmph.icmp6_solicited && idev && 1026 idev->cnf.drop_unsolicited_na) 1027 return; 1028 1029 if (!ndisc_parse_options(dev, msg->opt, ndoptlen, &ndopts)) { 1030 ND_PRINTK(2, warn, "NS: invalid ND option\n"); 1031 return; 1032 } 1033 if (ndopts.nd_opts_tgt_lladdr) { 1034 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr, dev); 1035 if (!lladdr) { 1036 ND_PRINTK(2, warn, 1037 "NA: invalid link-layer address length\n"); 1038 return; 1039 } 1040 } 1041 ifp = ipv6_get_ifaddr(dev_net(dev), &msg->target, dev, 1); 1042 if (ifp) { 1043 if (skb->pkt_type != PACKET_LOOPBACK 1044 && (ifp->flags & IFA_F_TENTATIVE)) { 1045 addrconf_dad_failure(skb, ifp); 1046 return; 1047 } 1048 /* What should we make now? The advertisement 1049 is invalid, but ndisc specs say nothing 1050 about it. It could be misconfiguration, or 1051 an smart proxy agent tries to help us :-) 1052 1053 We should not print the error if NA has been 1054 received from loopback - it is just our own 1055 unsolicited advertisement. 1056 */ 1057 if (skb->pkt_type != PACKET_LOOPBACK) 1058 ND_PRINTK(1, warn, 1059 "NA: %pM advertised our address %pI6c on %s!\n", 1060 eth_hdr(skb)->h_source, &ifp->addr, ifp->idev->dev->name); 1061 in6_ifa_put(ifp); 1062 return; 1063 } 1064 1065 neigh = neigh_lookup(&nd_tbl, &msg->target, dev); 1066 1067 /* RFC 9131 updates original Neighbour Discovery RFC 4861. 1068 * NAs with Target LL Address option without a corresponding 1069 * entry in the neighbour cache can now create a STALE neighbour 1070 * cache entry on routers. 1071 * 1072 * entry accept fwding solicited behaviour 1073 * ------- ------ ------ --------- ---------------------- 1074 * present X X 0 Set state to STALE 1075 * present X X 1 Set state to REACHABLE 1076 * absent 0 X X Do nothing 1077 * absent 1 0 X Do nothing 1078 * absent 1 1 X Add a new STALE entry 1079 * 1080 * Note that we don't do a (daddr == all-routers-mcast) check. 1081 */ 1082 new_state = msg->icmph.icmp6_solicited ? NUD_REACHABLE : NUD_STALE; 1083 if (!neigh && lladdr && idev && idev->cnf.forwarding) { 1084 if (accept_untracked_na(dev, saddr)) { 1085 neigh = neigh_create(&nd_tbl, &msg->target, dev); 1086 new_state = NUD_STALE; 1087 } 1088 } 1089 1090 if (neigh && !IS_ERR(neigh)) { 1091 u8 old_flags = neigh->flags; 1092 struct net *net = dev_net(dev); 1093 1094 if (neigh->nud_state & NUD_FAILED) 1095 goto out; 1096 1097 /* 1098 * Don't update the neighbor cache entry on a proxy NA from 1099 * ourselves because either the proxied node is off link or it 1100 * has already sent a NA to us. 1101 */ 1102 if (lladdr && !memcmp(lladdr, dev->dev_addr, dev->addr_len) && 1103 net->ipv6.devconf_all->forwarding && net->ipv6.devconf_all->proxy_ndp && 1104 pneigh_lookup(&nd_tbl, net, &msg->target, dev, 0)) { 1105 /* XXX: idev->cnf.proxy_ndp */ 1106 goto out; 1107 } 1108 1109 ndisc_update(dev, neigh, lladdr, 1110 new_state, 1111 NEIGH_UPDATE_F_WEAK_OVERRIDE| 1112 (msg->icmph.icmp6_override ? NEIGH_UPDATE_F_OVERRIDE : 0)| 1113 NEIGH_UPDATE_F_OVERRIDE_ISROUTER| 1114 (msg->icmph.icmp6_router ? NEIGH_UPDATE_F_ISROUTER : 0), 1115 NDISC_NEIGHBOUR_ADVERTISEMENT, &ndopts); 1116 1117 if ((old_flags & ~neigh->flags) & NTF_ROUTER) { 1118 /* 1119 * Change: router to host 1120 */ 1121 rt6_clean_tohost(dev_net(dev), saddr); 1122 } 1123 1124 out: 1125 neigh_release(neigh); 1126 } 1127 } 1128 1129 static void ndisc_recv_rs(struct sk_buff *skb) 1130 { 1131 struct rs_msg *rs_msg = (struct rs_msg *)skb_transport_header(skb); 1132 unsigned long ndoptlen = skb->len - sizeof(*rs_msg); 1133 struct neighbour *neigh; 1134 struct inet6_dev *idev; 1135 const struct in6_addr *saddr = &ipv6_hdr(skb)->saddr; 1136 struct ndisc_options ndopts; 1137 u8 *lladdr = NULL; 1138 1139 if (skb->len < sizeof(*rs_msg)) 1140 return; 1141 1142 idev = __in6_dev_get(skb->dev); 1143 if (!idev) { 1144 ND_PRINTK(1, err, "RS: can't find in6 device\n"); 1145 return; 1146 } 1147 1148 /* Don't accept RS if we're not in router mode */ 1149 if (!idev->cnf.forwarding) 1150 goto out; 1151 1152 /* 1153 * Don't update NCE if src = ::; 1154 * this implies that the source node has no ip address assigned yet. 1155 */ 1156 if (ipv6_addr_any(saddr)) 1157 goto out; 1158 1159 /* Parse ND options */ 1160 if (!ndisc_parse_options(skb->dev, rs_msg->opt, ndoptlen, &ndopts)) { 1161 ND_PRINTK(2, notice, "NS: invalid ND option, ignored\n"); 1162 goto out; 1163 } 1164 1165 if (ndopts.nd_opts_src_lladdr) { 1166 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr, 1167 skb->dev); 1168 if (!lladdr) 1169 goto out; 1170 } 1171 1172 neigh = __neigh_lookup(&nd_tbl, saddr, skb->dev, 1); 1173 if (neigh) { 1174 ndisc_update(skb->dev, neigh, lladdr, NUD_STALE, 1175 NEIGH_UPDATE_F_WEAK_OVERRIDE| 1176 NEIGH_UPDATE_F_OVERRIDE| 1177 NEIGH_UPDATE_F_OVERRIDE_ISROUTER, 1178 NDISC_ROUTER_SOLICITATION, &ndopts); 1179 neigh_release(neigh); 1180 } 1181 out: 1182 return; 1183 } 1184 1185 static void ndisc_ra_useropt(struct sk_buff *ra, struct nd_opt_hdr *opt) 1186 { 1187 struct icmp6hdr *icmp6h = (struct icmp6hdr *)skb_transport_header(ra); 1188 struct sk_buff *skb; 1189 struct nlmsghdr *nlh; 1190 struct nduseroptmsg *ndmsg; 1191 struct net *net = dev_net(ra->dev); 1192 int err; 1193 int base_size = NLMSG_ALIGN(sizeof(struct nduseroptmsg) 1194 + (opt->nd_opt_len << 3)); 1195 size_t msg_size = base_size + nla_total_size(sizeof(struct in6_addr)); 1196 1197 skb = nlmsg_new(msg_size, GFP_ATOMIC); 1198 if (!skb) { 1199 err = -ENOBUFS; 1200 goto errout; 1201 } 1202 1203 nlh = nlmsg_put(skb, 0, 0, RTM_NEWNDUSEROPT, base_size, 0); 1204 if (!nlh) { 1205 goto nla_put_failure; 1206 } 1207 1208 ndmsg = nlmsg_data(nlh); 1209 ndmsg->nduseropt_family = AF_INET6; 1210 ndmsg->nduseropt_ifindex = ra->dev->ifindex; 1211 ndmsg->nduseropt_icmp_type = icmp6h->icmp6_type; 1212 ndmsg->nduseropt_icmp_code = icmp6h->icmp6_code; 1213 ndmsg->nduseropt_opts_len = opt->nd_opt_len << 3; 1214 1215 memcpy(ndmsg + 1, opt, opt->nd_opt_len << 3); 1216 1217 if (nla_put_in6_addr(skb, NDUSEROPT_SRCADDR, &ipv6_hdr(ra)->saddr)) 1218 goto nla_put_failure; 1219 nlmsg_end(skb, nlh); 1220 1221 rtnl_notify(skb, net, 0, RTNLGRP_ND_USEROPT, NULL, GFP_ATOMIC); 1222 return; 1223 1224 nla_put_failure: 1225 nlmsg_free(skb); 1226 err = -EMSGSIZE; 1227 errout: 1228 rtnl_set_sk_err(net, RTNLGRP_ND_USEROPT, err); 1229 } 1230 1231 static void ndisc_router_discovery(struct sk_buff *skb) 1232 { 1233 struct ra_msg *ra_msg = (struct ra_msg *)skb_transport_header(skb); 1234 struct neighbour *neigh = NULL; 1235 struct inet6_dev *in6_dev; 1236 struct fib6_info *rt = NULL; 1237 u32 defrtr_usr_metric; 1238 struct net *net; 1239 int lifetime; 1240 struct ndisc_options ndopts; 1241 int optlen; 1242 unsigned int pref = 0; 1243 __u32 old_if_flags; 1244 bool send_ifinfo_notify = false; 1245 1246 __u8 *opt = (__u8 *)(ra_msg + 1); 1247 1248 optlen = (skb_tail_pointer(skb) - skb_transport_header(skb)) - 1249 sizeof(struct ra_msg); 1250 1251 ND_PRINTK(2, info, 1252 "RA: %s, dev: %s\n", 1253 __func__, skb->dev->name); 1254 if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) { 1255 ND_PRINTK(2, warn, "RA: source address is not link-local\n"); 1256 return; 1257 } 1258 if (optlen < 0) { 1259 ND_PRINTK(2, warn, "RA: packet too short\n"); 1260 return; 1261 } 1262 1263 #ifdef CONFIG_IPV6_NDISC_NODETYPE 1264 if (skb->ndisc_nodetype == NDISC_NODETYPE_HOST) { 1265 ND_PRINTK(2, warn, "RA: from host or unauthorized router\n"); 1266 return; 1267 } 1268 #endif 1269 1270 /* 1271 * set the RA_RECV flag in the interface 1272 */ 1273 1274 in6_dev = __in6_dev_get(skb->dev); 1275 if (!in6_dev) { 1276 ND_PRINTK(0, err, "RA: can't find inet6 device for %s\n", 1277 skb->dev->name); 1278 return; 1279 } 1280 1281 if (!ndisc_parse_options(skb->dev, opt, optlen, &ndopts)) { 1282 ND_PRINTK(2, warn, "RA: invalid ND options\n"); 1283 return; 1284 } 1285 1286 if (!ipv6_accept_ra(in6_dev)) { 1287 ND_PRINTK(2, info, 1288 "RA: %s, did not accept ra for dev: %s\n", 1289 __func__, skb->dev->name); 1290 goto skip_linkparms; 1291 } 1292 1293 #ifdef CONFIG_IPV6_NDISC_NODETYPE 1294 /* skip link-specific parameters from interior routers */ 1295 if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT) { 1296 ND_PRINTK(2, info, 1297 "RA: %s, nodetype is NODEFAULT, dev: %s\n", 1298 __func__, skb->dev->name); 1299 goto skip_linkparms; 1300 } 1301 #endif 1302 1303 if (in6_dev->if_flags & IF_RS_SENT) { 1304 /* 1305 * flag that an RA was received after an RS was sent 1306 * out on this interface. 1307 */ 1308 in6_dev->if_flags |= IF_RA_RCVD; 1309 } 1310 1311 /* 1312 * Remember the managed/otherconf flags from most recently 1313 * received RA message (RFC 2462) -- yoshfuji 1314 */ 1315 old_if_flags = in6_dev->if_flags; 1316 in6_dev->if_flags = (in6_dev->if_flags & ~(IF_RA_MANAGED | 1317 IF_RA_OTHERCONF)) | 1318 (ra_msg->icmph.icmp6_addrconf_managed ? 1319 IF_RA_MANAGED : 0) | 1320 (ra_msg->icmph.icmp6_addrconf_other ? 1321 IF_RA_OTHERCONF : 0); 1322 1323 if (old_if_flags != in6_dev->if_flags) 1324 send_ifinfo_notify = true; 1325 1326 if (!in6_dev->cnf.accept_ra_defrtr) { 1327 ND_PRINTK(2, info, 1328 "RA: %s, defrtr is false for dev: %s\n", 1329 __func__, skb->dev->name); 1330 goto skip_defrtr; 1331 } 1332 1333 /* Do not accept RA with source-addr found on local machine unless 1334 * accept_ra_from_local is set to true. 1335 */ 1336 net = dev_net(in6_dev->dev); 1337 if (!in6_dev->cnf.accept_ra_from_local && 1338 ipv6_chk_addr(net, &ipv6_hdr(skb)->saddr, in6_dev->dev, 0)) { 1339 ND_PRINTK(2, info, 1340 "RA from local address detected on dev: %s: default router ignored\n", 1341 skb->dev->name); 1342 goto skip_defrtr; 1343 } 1344 1345 lifetime = ntohs(ra_msg->icmph.icmp6_rt_lifetime); 1346 1347 #ifdef CONFIG_IPV6_ROUTER_PREF 1348 pref = ra_msg->icmph.icmp6_router_pref; 1349 /* 10b is handled as if it were 00b (medium) */ 1350 if (pref == ICMPV6_ROUTER_PREF_INVALID || 1351 !in6_dev->cnf.accept_ra_rtr_pref) 1352 pref = ICMPV6_ROUTER_PREF_MEDIUM; 1353 #endif 1354 /* routes added from RAs do not use nexthop objects */ 1355 rt = rt6_get_dflt_router(net, &ipv6_hdr(skb)->saddr, skb->dev); 1356 if (rt) { 1357 neigh = ip6_neigh_lookup(&rt->fib6_nh->fib_nh_gw6, 1358 rt->fib6_nh->fib_nh_dev, NULL, 1359 &ipv6_hdr(skb)->saddr); 1360 if (!neigh) { 1361 ND_PRINTK(0, err, 1362 "RA: %s got default router without neighbour\n", 1363 __func__); 1364 fib6_info_release(rt); 1365 return; 1366 } 1367 } 1368 /* Set default route metric as specified by user */ 1369 defrtr_usr_metric = in6_dev->cnf.ra_defrtr_metric; 1370 /* delete the route if lifetime is 0 or if metric needs change */ 1371 if (rt && (lifetime == 0 || rt->fib6_metric != defrtr_usr_metric)) { 1372 ip6_del_rt(net, rt, false); 1373 rt = NULL; 1374 } 1375 1376 ND_PRINTK(3, info, "RA: rt: %p lifetime: %d, metric: %d, for dev: %s\n", 1377 rt, lifetime, defrtr_usr_metric, skb->dev->name); 1378 if (!rt && lifetime) { 1379 ND_PRINTK(3, info, "RA: adding default router\n"); 1380 1381 rt = rt6_add_dflt_router(net, &ipv6_hdr(skb)->saddr, 1382 skb->dev, pref, defrtr_usr_metric); 1383 if (!rt) { 1384 ND_PRINTK(0, err, 1385 "RA: %s failed to add default route\n", 1386 __func__); 1387 return; 1388 } 1389 1390 neigh = ip6_neigh_lookup(&rt->fib6_nh->fib_nh_gw6, 1391 rt->fib6_nh->fib_nh_dev, NULL, 1392 &ipv6_hdr(skb)->saddr); 1393 if (!neigh) { 1394 ND_PRINTK(0, err, 1395 "RA: %s got default router without neighbour\n", 1396 __func__); 1397 fib6_info_release(rt); 1398 return; 1399 } 1400 neigh->flags |= NTF_ROUTER; 1401 } else if (rt && IPV6_EXTRACT_PREF(rt->fib6_flags) != pref) { 1402 struct nl_info nlinfo = { 1403 .nl_net = net, 1404 }; 1405 rt->fib6_flags = (rt->fib6_flags & ~RTF_PREF_MASK) | RTF_PREF(pref); 1406 inet6_rt_notify(RTM_NEWROUTE, rt, &nlinfo, NLM_F_REPLACE); 1407 } 1408 1409 if (rt) 1410 fib6_set_expires(rt, jiffies + (HZ * lifetime)); 1411 if (in6_dev->cnf.accept_ra_min_hop_limit < 256 && 1412 ra_msg->icmph.icmp6_hop_limit) { 1413 if (in6_dev->cnf.accept_ra_min_hop_limit <= ra_msg->icmph.icmp6_hop_limit) { 1414 in6_dev->cnf.hop_limit = ra_msg->icmph.icmp6_hop_limit; 1415 fib6_metric_set(rt, RTAX_HOPLIMIT, 1416 ra_msg->icmph.icmp6_hop_limit); 1417 } else { 1418 ND_PRINTK(2, warn, "RA: Got route advertisement with lower hop_limit than minimum\n"); 1419 } 1420 } 1421 1422 skip_defrtr: 1423 1424 /* 1425 * Update Reachable Time and Retrans Timer 1426 */ 1427 1428 if (in6_dev->nd_parms) { 1429 unsigned long rtime = ntohl(ra_msg->retrans_timer); 1430 1431 if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/HZ) { 1432 rtime = (rtime*HZ)/1000; 1433 if (rtime < HZ/100) 1434 rtime = HZ/100; 1435 NEIGH_VAR_SET(in6_dev->nd_parms, RETRANS_TIME, rtime); 1436 in6_dev->tstamp = jiffies; 1437 send_ifinfo_notify = true; 1438 } 1439 1440 rtime = ntohl(ra_msg->reachable_time); 1441 if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/(3*HZ)) { 1442 rtime = (rtime*HZ)/1000; 1443 1444 if (rtime < HZ/10) 1445 rtime = HZ/10; 1446 1447 if (rtime != NEIGH_VAR(in6_dev->nd_parms, BASE_REACHABLE_TIME)) { 1448 NEIGH_VAR_SET(in6_dev->nd_parms, 1449 BASE_REACHABLE_TIME, rtime); 1450 NEIGH_VAR_SET(in6_dev->nd_parms, 1451 GC_STALETIME, 3 * rtime); 1452 in6_dev->nd_parms->reachable_time = neigh_rand_reach_time(rtime); 1453 in6_dev->tstamp = jiffies; 1454 send_ifinfo_notify = true; 1455 } 1456 } 1457 } 1458 1459 skip_linkparms: 1460 1461 /* 1462 * Process options. 1463 */ 1464 1465 if (!neigh) 1466 neigh = __neigh_lookup(&nd_tbl, &ipv6_hdr(skb)->saddr, 1467 skb->dev, 1); 1468 if (neigh) { 1469 u8 *lladdr = NULL; 1470 if (ndopts.nd_opts_src_lladdr) { 1471 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr, 1472 skb->dev); 1473 if (!lladdr) { 1474 ND_PRINTK(2, warn, 1475 "RA: invalid link-layer address length\n"); 1476 goto out; 1477 } 1478 } 1479 ndisc_update(skb->dev, neigh, lladdr, NUD_STALE, 1480 NEIGH_UPDATE_F_WEAK_OVERRIDE| 1481 NEIGH_UPDATE_F_OVERRIDE| 1482 NEIGH_UPDATE_F_OVERRIDE_ISROUTER| 1483 NEIGH_UPDATE_F_ISROUTER, 1484 NDISC_ROUTER_ADVERTISEMENT, &ndopts); 1485 } 1486 1487 if (!ipv6_accept_ra(in6_dev)) { 1488 ND_PRINTK(2, info, 1489 "RA: %s, accept_ra is false for dev: %s\n", 1490 __func__, skb->dev->name); 1491 goto out; 1492 } 1493 1494 #ifdef CONFIG_IPV6_ROUTE_INFO 1495 if (!in6_dev->cnf.accept_ra_from_local && 1496 ipv6_chk_addr(dev_net(in6_dev->dev), &ipv6_hdr(skb)->saddr, 1497 in6_dev->dev, 0)) { 1498 ND_PRINTK(2, info, 1499 "RA from local address detected on dev: %s: router info ignored.\n", 1500 skb->dev->name); 1501 goto skip_routeinfo; 1502 } 1503 1504 if (in6_dev->cnf.accept_ra_rtr_pref && ndopts.nd_opts_ri) { 1505 struct nd_opt_hdr *p; 1506 for (p = ndopts.nd_opts_ri; 1507 p; 1508 p = ndisc_next_option(p, ndopts.nd_opts_ri_end)) { 1509 struct route_info *ri = (struct route_info *)p; 1510 #ifdef CONFIG_IPV6_NDISC_NODETYPE 1511 if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT && 1512 ri->prefix_len == 0) 1513 continue; 1514 #endif 1515 if (ri->prefix_len == 0 && 1516 !in6_dev->cnf.accept_ra_defrtr) 1517 continue; 1518 if (ri->prefix_len < in6_dev->cnf.accept_ra_rt_info_min_plen) 1519 continue; 1520 if (ri->prefix_len > in6_dev->cnf.accept_ra_rt_info_max_plen) 1521 continue; 1522 rt6_route_rcv(skb->dev, (u8 *)p, (p->nd_opt_len) << 3, 1523 &ipv6_hdr(skb)->saddr); 1524 } 1525 } 1526 1527 skip_routeinfo: 1528 #endif 1529 1530 #ifdef CONFIG_IPV6_NDISC_NODETYPE 1531 /* skip link-specific ndopts from interior routers */ 1532 if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT) { 1533 ND_PRINTK(2, info, 1534 "RA: %s, nodetype is NODEFAULT (interior routes), dev: %s\n", 1535 __func__, skb->dev->name); 1536 goto out; 1537 } 1538 #endif 1539 1540 if (in6_dev->cnf.accept_ra_pinfo && ndopts.nd_opts_pi) { 1541 struct nd_opt_hdr *p; 1542 for (p = ndopts.nd_opts_pi; 1543 p; 1544 p = ndisc_next_option(p, ndopts.nd_opts_pi_end)) { 1545 addrconf_prefix_rcv(skb->dev, (u8 *)p, 1546 (p->nd_opt_len) << 3, 1547 ndopts.nd_opts_src_lladdr != NULL); 1548 } 1549 } 1550 1551 if (ndopts.nd_opts_mtu && in6_dev->cnf.accept_ra_mtu) { 1552 __be32 n; 1553 u32 mtu; 1554 1555 memcpy(&n, ((u8 *)(ndopts.nd_opts_mtu+1))+2, sizeof(mtu)); 1556 mtu = ntohl(n); 1557 1558 if (in6_dev->ra_mtu != mtu) { 1559 in6_dev->ra_mtu = mtu; 1560 send_ifinfo_notify = true; 1561 } 1562 1563 if (mtu < IPV6_MIN_MTU || mtu > skb->dev->mtu) { 1564 ND_PRINTK(2, warn, "RA: invalid mtu: %d\n", mtu); 1565 } else if (in6_dev->cnf.mtu6 != mtu) { 1566 in6_dev->cnf.mtu6 = mtu; 1567 fib6_metric_set(rt, RTAX_MTU, mtu); 1568 rt6_mtu_change(skb->dev, mtu); 1569 } 1570 } 1571 1572 if (ndopts.nd_useropts) { 1573 struct nd_opt_hdr *p; 1574 for (p = ndopts.nd_useropts; 1575 p; 1576 p = ndisc_next_useropt(skb->dev, p, 1577 ndopts.nd_useropts_end)) { 1578 ndisc_ra_useropt(skb, p); 1579 } 1580 } 1581 1582 if (ndopts.nd_opts_tgt_lladdr || ndopts.nd_opts_rh) { 1583 ND_PRINTK(2, warn, "RA: invalid RA options\n"); 1584 } 1585 out: 1586 /* Send a notify if RA changed managed/otherconf flags or 1587 * timer settings or ra_mtu value 1588 */ 1589 if (send_ifinfo_notify) 1590 inet6_ifinfo_notify(RTM_NEWLINK, in6_dev); 1591 1592 fib6_info_release(rt); 1593 if (neigh) 1594 neigh_release(neigh); 1595 } 1596 1597 static void ndisc_redirect_rcv(struct sk_buff *skb) 1598 { 1599 u8 *hdr; 1600 struct ndisc_options ndopts; 1601 struct rd_msg *msg = (struct rd_msg *)skb_transport_header(skb); 1602 u32 ndoptlen = skb_tail_pointer(skb) - (skb_transport_header(skb) + 1603 offsetof(struct rd_msg, opt)); 1604 1605 #ifdef CONFIG_IPV6_NDISC_NODETYPE 1606 switch (skb->ndisc_nodetype) { 1607 case NDISC_NODETYPE_HOST: 1608 case NDISC_NODETYPE_NODEFAULT: 1609 ND_PRINTK(2, warn, 1610 "Redirect: from host or unauthorized router\n"); 1611 return; 1612 } 1613 #endif 1614 1615 if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) { 1616 ND_PRINTK(2, warn, 1617 "Redirect: source address is not link-local\n"); 1618 return; 1619 } 1620 1621 if (!ndisc_parse_options(skb->dev, msg->opt, ndoptlen, &ndopts)) 1622 return; 1623 1624 if (!ndopts.nd_opts_rh) { 1625 ip6_redirect_no_header(skb, dev_net(skb->dev), 1626 skb->dev->ifindex); 1627 return; 1628 } 1629 1630 hdr = (u8 *)ndopts.nd_opts_rh; 1631 hdr += 8; 1632 if (!pskb_pull(skb, hdr - skb_transport_header(skb))) 1633 return; 1634 1635 icmpv6_notify(skb, NDISC_REDIRECT, 0, 0); 1636 } 1637 1638 static void ndisc_fill_redirect_hdr_option(struct sk_buff *skb, 1639 struct sk_buff *orig_skb, 1640 int rd_len) 1641 { 1642 u8 *opt = skb_put(skb, rd_len); 1643 1644 memset(opt, 0, 8); 1645 *(opt++) = ND_OPT_REDIRECT_HDR; 1646 *(opt++) = (rd_len >> 3); 1647 opt += 6; 1648 1649 skb_copy_bits(orig_skb, skb_network_offset(orig_skb), opt, 1650 rd_len - 8); 1651 } 1652 1653 void ndisc_send_redirect(struct sk_buff *skb, const struct in6_addr *target) 1654 { 1655 struct net_device *dev = skb->dev; 1656 struct net *net = dev_net(dev); 1657 struct sock *sk = net->ipv6.ndisc_sk; 1658 int optlen = 0; 1659 struct inet_peer *peer; 1660 struct sk_buff *buff; 1661 struct rd_msg *msg; 1662 struct in6_addr saddr_buf; 1663 struct rt6_info *rt; 1664 struct dst_entry *dst; 1665 struct flowi6 fl6; 1666 int rd_len; 1667 u8 ha_buf[MAX_ADDR_LEN], *ha = NULL, 1668 ops_data_buf[NDISC_OPS_REDIRECT_DATA_SPACE], *ops_data = NULL; 1669 bool ret; 1670 1671 if (netif_is_l3_master(skb->dev)) { 1672 dev = __dev_get_by_index(dev_net(skb->dev), IPCB(skb)->iif); 1673 if (!dev) 1674 return; 1675 } 1676 1677 if (ipv6_get_lladdr(dev, &saddr_buf, IFA_F_TENTATIVE)) { 1678 ND_PRINTK(2, warn, "Redirect: no link-local address on %s\n", 1679 dev->name); 1680 return; 1681 } 1682 1683 if (!ipv6_addr_equal(&ipv6_hdr(skb)->daddr, target) && 1684 ipv6_addr_type(target) != (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) { 1685 ND_PRINTK(2, warn, 1686 "Redirect: target address is not link-local unicast\n"); 1687 return; 1688 } 1689 1690 icmpv6_flow_init(sk, &fl6, NDISC_REDIRECT, 1691 &saddr_buf, &ipv6_hdr(skb)->saddr, dev->ifindex); 1692 1693 dst = ip6_route_output(net, NULL, &fl6); 1694 if (dst->error) { 1695 dst_release(dst); 1696 return; 1697 } 1698 dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), NULL, 0); 1699 if (IS_ERR(dst)) 1700 return; 1701 1702 rt = (struct rt6_info *) dst; 1703 1704 if (rt->rt6i_flags & RTF_GATEWAY) { 1705 ND_PRINTK(2, warn, 1706 "Redirect: destination is not a neighbour\n"); 1707 goto release; 1708 } 1709 peer = inet_getpeer_v6(net->ipv6.peers, &ipv6_hdr(skb)->saddr, 1); 1710 ret = inet_peer_xrlim_allow(peer, 1*HZ); 1711 if (peer) 1712 inet_putpeer(peer); 1713 if (!ret) 1714 goto release; 1715 1716 if (dev->addr_len) { 1717 struct neighbour *neigh = dst_neigh_lookup(skb_dst(skb), target); 1718 if (!neigh) { 1719 ND_PRINTK(2, warn, 1720 "Redirect: no neigh for target address\n"); 1721 goto release; 1722 } 1723 1724 read_lock_bh(&neigh->lock); 1725 if (neigh->nud_state & NUD_VALID) { 1726 memcpy(ha_buf, neigh->ha, dev->addr_len); 1727 read_unlock_bh(&neigh->lock); 1728 ha = ha_buf; 1729 optlen += ndisc_redirect_opt_addr_space(dev, neigh, 1730 ops_data_buf, 1731 &ops_data); 1732 } else 1733 read_unlock_bh(&neigh->lock); 1734 1735 neigh_release(neigh); 1736 } 1737 1738 rd_len = min_t(unsigned int, 1739 IPV6_MIN_MTU - sizeof(struct ipv6hdr) - sizeof(*msg) - optlen, 1740 skb->len + 8); 1741 rd_len &= ~0x7; 1742 optlen += rd_len; 1743 1744 buff = ndisc_alloc_skb(dev, sizeof(*msg) + optlen); 1745 if (!buff) 1746 goto release; 1747 1748 msg = skb_put(buff, sizeof(*msg)); 1749 *msg = (struct rd_msg) { 1750 .icmph = { 1751 .icmp6_type = NDISC_REDIRECT, 1752 }, 1753 .target = *target, 1754 .dest = ipv6_hdr(skb)->daddr, 1755 }; 1756 1757 /* 1758 * include target_address option 1759 */ 1760 1761 if (ha) 1762 ndisc_fill_redirect_addr_option(buff, ha, ops_data); 1763 1764 /* 1765 * build redirect option and copy skb over to the new packet. 1766 */ 1767 1768 if (rd_len) 1769 ndisc_fill_redirect_hdr_option(buff, skb, rd_len); 1770 1771 skb_dst_set(buff, dst); 1772 ndisc_send_skb(buff, &ipv6_hdr(skb)->saddr, &saddr_buf); 1773 return; 1774 1775 release: 1776 dst_release(dst); 1777 } 1778 1779 static void pndisc_redo(struct sk_buff *skb) 1780 { 1781 ndisc_recv_ns(skb); 1782 kfree_skb(skb); 1783 } 1784 1785 static int ndisc_is_multicast(const void *pkey) 1786 { 1787 return ipv6_addr_is_multicast((struct in6_addr *)pkey); 1788 } 1789 1790 static bool ndisc_suppress_frag_ndisc(struct sk_buff *skb) 1791 { 1792 struct inet6_dev *idev = __in6_dev_get(skb->dev); 1793 1794 if (!idev) 1795 return true; 1796 if (IP6CB(skb)->flags & IP6SKB_FRAGMENTED && 1797 idev->cnf.suppress_frag_ndisc) { 1798 net_warn_ratelimited("Received fragmented ndisc packet. Carefully consider disabling suppress_frag_ndisc.\n"); 1799 return true; 1800 } 1801 return false; 1802 } 1803 1804 int ndisc_rcv(struct sk_buff *skb) 1805 { 1806 struct nd_msg *msg; 1807 1808 if (ndisc_suppress_frag_ndisc(skb)) 1809 return 0; 1810 1811 if (skb_linearize(skb)) 1812 return 0; 1813 1814 msg = (struct nd_msg *)skb_transport_header(skb); 1815 1816 __skb_push(skb, skb->data - skb_transport_header(skb)); 1817 1818 if (ipv6_hdr(skb)->hop_limit != 255) { 1819 ND_PRINTK(2, warn, "NDISC: invalid hop-limit: %d\n", 1820 ipv6_hdr(skb)->hop_limit); 1821 return 0; 1822 } 1823 1824 if (msg->icmph.icmp6_code != 0) { 1825 ND_PRINTK(2, warn, "NDISC: invalid ICMPv6 code: %d\n", 1826 msg->icmph.icmp6_code); 1827 return 0; 1828 } 1829 1830 switch (msg->icmph.icmp6_type) { 1831 case NDISC_NEIGHBOUR_SOLICITATION: 1832 memset(NEIGH_CB(skb), 0, sizeof(struct neighbour_cb)); 1833 ndisc_recv_ns(skb); 1834 break; 1835 1836 case NDISC_NEIGHBOUR_ADVERTISEMENT: 1837 ndisc_recv_na(skb); 1838 break; 1839 1840 case NDISC_ROUTER_SOLICITATION: 1841 ndisc_recv_rs(skb); 1842 break; 1843 1844 case NDISC_ROUTER_ADVERTISEMENT: 1845 ndisc_router_discovery(skb); 1846 break; 1847 1848 case NDISC_REDIRECT: 1849 ndisc_redirect_rcv(skb); 1850 break; 1851 } 1852 1853 return 0; 1854 } 1855 1856 static int ndisc_netdev_event(struct notifier_block *this, unsigned long event, void *ptr) 1857 { 1858 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 1859 struct netdev_notifier_change_info *change_info; 1860 struct net *net = dev_net(dev); 1861 struct inet6_dev *idev; 1862 bool evict_nocarrier; 1863 1864 switch (event) { 1865 case NETDEV_CHANGEADDR: 1866 neigh_changeaddr(&nd_tbl, dev); 1867 fib6_run_gc(0, net, false); 1868 fallthrough; 1869 case NETDEV_UP: 1870 idev = in6_dev_get(dev); 1871 if (!idev) 1872 break; 1873 if (idev->cnf.ndisc_notify || 1874 net->ipv6.devconf_all->ndisc_notify) 1875 ndisc_send_unsol_na(dev); 1876 in6_dev_put(idev); 1877 break; 1878 case NETDEV_CHANGE: 1879 idev = in6_dev_get(dev); 1880 if (!idev) 1881 evict_nocarrier = true; 1882 else { 1883 evict_nocarrier = idev->cnf.ndisc_evict_nocarrier && 1884 net->ipv6.devconf_all->ndisc_evict_nocarrier; 1885 in6_dev_put(idev); 1886 } 1887 1888 change_info = ptr; 1889 if (change_info->flags_changed & IFF_NOARP) 1890 neigh_changeaddr(&nd_tbl, dev); 1891 if (evict_nocarrier && !netif_carrier_ok(dev)) 1892 neigh_carrier_down(&nd_tbl, dev); 1893 break; 1894 case NETDEV_DOWN: 1895 neigh_ifdown(&nd_tbl, dev); 1896 fib6_run_gc(0, net, false); 1897 break; 1898 case NETDEV_NOTIFY_PEERS: 1899 ndisc_send_unsol_na(dev); 1900 break; 1901 default: 1902 break; 1903 } 1904 1905 return NOTIFY_DONE; 1906 } 1907 1908 static struct notifier_block ndisc_netdev_notifier = { 1909 .notifier_call = ndisc_netdev_event, 1910 .priority = ADDRCONF_NOTIFY_PRIORITY - 5, 1911 }; 1912 1913 #ifdef CONFIG_SYSCTL 1914 static void ndisc_warn_deprecated_sysctl(struct ctl_table *ctl, 1915 const char *func, const char *dev_name) 1916 { 1917 static char warncomm[TASK_COMM_LEN]; 1918 static int warned; 1919 if (strcmp(warncomm, current->comm) && warned < 5) { 1920 strcpy(warncomm, current->comm); 1921 pr_warn("process `%s' is using deprecated sysctl (%s) net.ipv6.neigh.%s.%s - use net.ipv6.neigh.%s.%s_ms instead\n", 1922 warncomm, func, 1923 dev_name, ctl->procname, 1924 dev_name, ctl->procname); 1925 warned++; 1926 } 1927 } 1928 1929 int ndisc_ifinfo_sysctl_change(struct ctl_table *ctl, int write, void *buffer, 1930 size_t *lenp, loff_t *ppos) 1931 { 1932 struct net_device *dev = ctl->extra1; 1933 struct inet6_dev *idev; 1934 int ret; 1935 1936 if ((strcmp(ctl->procname, "retrans_time") == 0) || 1937 (strcmp(ctl->procname, "base_reachable_time") == 0)) 1938 ndisc_warn_deprecated_sysctl(ctl, "syscall", dev ? dev->name : "default"); 1939 1940 if (strcmp(ctl->procname, "retrans_time") == 0) 1941 ret = neigh_proc_dointvec(ctl, write, buffer, lenp, ppos); 1942 1943 else if (strcmp(ctl->procname, "base_reachable_time") == 0) 1944 ret = neigh_proc_dointvec_jiffies(ctl, write, 1945 buffer, lenp, ppos); 1946 1947 else if ((strcmp(ctl->procname, "retrans_time_ms") == 0) || 1948 (strcmp(ctl->procname, "base_reachable_time_ms") == 0)) 1949 ret = neigh_proc_dointvec_ms_jiffies(ctl, write, 1950 buffer, lenp, ppos); 1951 else 1952 ret = -1; 1953 1954 if (write && ret == 0 && dev && (idev = in6_dev_get(dev)) != NULL) { 1955 if (ctl->data == &NEIGH_VAR(idev->nd_parms, BASE_REACHABLE_TIME)) 1956 idev->nd_parms->reachable_time = 1957 neigh_rand_reach_time(NEIGH_VAR(idev->nd_parms, BASE_REACHABLE_TIME)); 1958 idev->tstamp = jiffies; 1959 inet6_ifinfo_notify(RTM_NEWLINK, idev); 1960 in6_dev_put(idev); 1961 } 1962 return ret; 1963 } 1964 1965 1966 #endif 1967 1968 static int __net_init ndisc_net_init(struct net *net) 1969 { 1970 struct ipv6_pinfo *np; 1971 struct sock *sk; 1972 int err; 1973 1974 err = inet_ctl_sock_create(&sk, PF_INET6, 1975 SOCK_RAW, IPPROTO_ICMPV6, net); 1976 if (err < 0) { 1977 ND_PRINTK(0, err, 1978 "NDISC: Failed to initialize the control socket (err %d)\n", 1979 err); 1980 return err; 1981 } 1982 1983 net->ipv6.ndisc_sk = sk; 1984 1985 np = inet6_sk(sk); 1986 np->hop_limit = 255; 1987 /* Do not loopback ndisc messages */ 1988 np->mc_loop = 0; 1989 1990 return 0; 1991 } 1992 1993 static void __net_exit ndisc_net_exit(struct net *net) 1994 { 1995 inet_ctl_sock_destroy(net->ipv6.ndisc_sk); 1996 } 1997 1998 static struct pernet_operations ndisc_net_ops = { 1999 .init = ndisc_net_init, 2000 .exit = ndisc_net_exit, 2001 }; 2002 2003 int __init ndisc_init(void) 2004 { 2005 int err; 2006 2007 err = register_pernet_subsys(&ndisc_net_ops); 2008 if (err) 2009 return err; 2010 /* 2011 * Initialize the neighbour table 2012 */ 2013 neigh_table_init(NEIGH_ND_TABLE, &nd_tbl); 2014 2015 #ifdef CONFIG_SYSCTL 2016 err = neigh_sysctl_register(NULL, &nd_tbl.parms, 2017 ndisc_ifinfo_sysctl_change); 2018 if (err) 2019 goto out_unregister_pernet; 2020 out: 2021 #endif 2022 return err; 2023 2024 #ifdef CONFIG_SYSCTL 2025 out_unregister_pernet: 2026 unregister_pernet_subsys(&ndisc_net_ops); 2027 goto out; 2028 #endif 2029 } 2030 2031 int __init ndisc_late_init(void) 2032 { 2033 return register_netdevice_notifier(&ndisc_netdev_notifier); 2034 } 2035 2036 void ndisc_late_cleanup(void) 2037 { 2038 unregister_netdevice_notifier(&ndisc_netdev_notifier); 2039 } 2040 2041 void ndisc_cleanup(void) 2042 { 2043 #ifdef CONFIG_SYSCTL 2044 neigh_sysctl_unregister(&nd_tbl.parms); 2045 #endif 2046 neigh_table_clear(NEIGH_ND_TABLE, &nd_tbl); 2047 unregister_pernet_subsys(&ndisc_net_ops); 2048 } 2049