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 void ndisc_recv_na(struct sk_buff *skb) 971 { 972 struct nd_msg *msg = (struct nd_msg *)skb_transport_header(skb); 973 struct in6_addr *saddr = &ipv6_hdr(skb)->saddr; 974 const struct in6_addr *daddr = &ipv6_hdr(skb)->daddr; 975 u8 *lladdr = NULL; 976 u32 ndoptlen = skb_tail_pointer(skb) - (skb_transport_header(skb) + 977 offsetof(struct nd_msg, opt)); 978 struct ndisc_options ndopts; 979 struct net_device *dev = skb->dev; 980 struct inet6_dev *idev = __in6_dev_get(dev); 981 struct inet6_ifaddr *ifp; 982 struct neighbour *neigh; 983 u8 new_state; 984 985 if (skb->len < sizeof(struct nd_msg)) { 986 ND_PRINTK(2, warn, "NA: packet too short\n"); 987 return; 988 } 989 990 if (ipv6_addr_is_multicast(&msg->target)) { 991 ND_PRINTK(2, warn, "NA: target address is multicast\n"); 992 return; 993 } 994 995 if (ipv6_addr_is_multicast(daddr) && 996 msg->icmph.icmp6_solicited) { 997 ND_PRINTK(2, warn, "NA: solicited NA is multicasted\n"); 998 return; 999 } 1000 1001 /* For some 802.11 wireless deployments (and possibly other networks), 1002 * there will be a NA proxy and unsolicitd packets are attacks 1003 * and thus should not be accepted. 1004 * drop_unsolicited_na takes precedence over accept_untracked_na 1005 */ 1006 if (!msg->icmph.icmp6_solicited && idev && 1007 idev->cnf.drop_unsolicited_na) 1008 return; 1009 1010 if (!ndisc_parse_options(dev, msg->opt, ndoptlen, &ndopts)) { 1011 ND_PRINTK(2, warn, "NS: invalid ND option\n"); 1012 return; 1013 } 1014 if (ndopts.nd_opts_tgt_lladdr) { 1015 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr, dev); 1016 if (!lladdr) { 1017 ND_PRINTK(2, warn, 1018 "NA: invalid link-layer address length\n"); 1019 return; 1020 } 1021 } 1022 ifp = ipv6_get_ifaddr(dev_net(dev), &msg->target, dev, 1); 1023 if (ifp) { 1024 if (skb->pkt_type != PACKET_LOOPBACK 1025 && (ifp->flags & IFA_F_TENTATIVE)) { 1026 addrconf_dad_failure(skb, ifp); 1027 return; 1028 } 1029 /* What should we make now? The advertisement 1030 is invalid, but ndisc specs say nothing 1031 about it. It could be misconfiguration, or 1032 an smart proxy agent tries to help us :-) 1033 1034 We should not print the error if NA has been 1035 received from loopback - it is just our own 1036 unsolicited advertisement. 1037 */ 1038 if (skb->pkt_type != PACKET_LOOPBACK) 1039 ND_PRINTK(1, warn, 1040 "NA: %pM advertised our address %pI6c on %s!\n", 1041 eth_hdr(skb)->h_source, &ifp->addr, ifp->idev->dev->name); 1042 in6_ifa_put(ifp); 1043 return; 1044 } 1045 1046 neigh = neigh_lookup(&nd_tbl, &msg->target, dev); 1047 1048 /* RFC 9131 updates original Neighbour Discovery RFC 4861. 1049 * NAs with Target LL Address option without a corresponding 1050 * entry in the neighbour cache can now create a STALE neighbour 1051 * cache entry on routers. 1052 * 1053 * entry accept fwding solicited behaviour 1054 * ------- ------ ------ --------- ---------------------- 1055 * present X X 0 Set state to STALE 1056 * present X X 1 Set state to REACHABLE 1057 * absent 0 X X Do nothing 1058 * absent 1 0 X Do nothing 1059 * absent 1 1 X Add a new STALE entry 1060 * 1061 * Note that we don't do a (daddr == all-routers-mcast) check. 1062 */ 1063 new_state = msg->icmph.icmp6_solicited ? NUD_REACHABLE : NUD_STALE; 1064 if (!neigh && lladdr && 1065 idev && idev->cnf.forwarding && 1066 idev->cnf.accept_untracked_na) { 1067 neigh = neigh_create(&nd_tbl, &msg->target, dev); 1068 new_state = NUD_STALE; 1069 } 1070 1071 if (neigh && !IS_ERR(neigh)) { 1072 u8 old_flags = neigh->flags; 1073 struct net *net = dev_net(dev); 1074 1075 if (neigh->nud_state & NUD_FAILED) 1076 goto out; 1077 1078 /* 1079 * Don't update the neighbor cache entry on a proxy NA from 1080 * ourselves because either the proxied node is off link or it 1081 * has already sent a NA to us. 1082 */ 1083 if (lladdr && !memcmp(lladdr, dev->dev_addr, dev->addr_len) && 1084 net->ipv6.devconf_all->forwarding && net->ipv6.devconf_all->proxy_ndp && 1085 pneigh_lookup(&nd_tbl, net, &msg->target, dev, 0)) { 1086 /* XXX: idev->cnf.proxy_ndp */ 1087 goto out; 1088 } 1089 1090 ndisc_update(dev, neigh, lladdr, 1091 new_state, 1092 NEIGH_UPDATE_F_WEAK_OVERRIDE| 1093 (msg->icmph.icmp6_override ? NEIGH_UPDATE_F_OVERRIDE : 0)| 1094 NEIGH_UPDATE_F_OVERRIDE_ISROUTER| 1095 (msg->icmph.icmp6_router ? NEIGH_UPDATE_F_ISROUTER : 0), 1096 NDISC_NEIGHBOUR_ADVERTISEMENT, &ndopts); 1097 1098 if ((old_flags & ~neigh->flags) & NTF_ROUTER) { 1099 /* 1100 * Change: router to host 1101 */ 1102 rt6_clean_tohost(dev_net(dev), saddr); 1103 } 1104 1105 out: 1106 neigh_release(neigh); 1107 } 1108 } 1109 1110 static void ndisc_recv_rs(struct sk_buff *skb) 1111 { 1112 struct rs_msg *rs_msg = (struct rs_msg *)skb_transport_header(skb); 1113 unsigned long ndoptlen = skb->len - sizeof(*rs_msg); 1114 struct neighbour *neigh; 1115 struct inet6_dev *idev; 1116 const struct in6_addr *saddr = &ipv6_hdr(skb)->saddr; 1117 struct ndisc_options ndopts; 1118 u8 *lladdr = NULL; 1119 1120 if (skb->len < sizeof(*rs_msg)) 1121 return; 1122 1123 idev = __in6_dev_get(skb->dev); 1124 if (!idev) { 1125 ND_PRINTK(1, err, "RS: can't find in6 device\n"); 1126 return; 1127 } 1128 1129 /* Don't accept RS if we're not in router mode */ 1130 if (!idev->cnf.forwarding) 1131 goto out; 1132 1133 /* 1134 * Don't update NCE if src = ::; 1135 * this implies that the source node has no ip address assigned yet. 1136 */ 1137 if (ipv6_addr_any(saddr)) 1138 goto out; 1139 1140 /* Parse ND options */ 1141 if (!ndisc_parse_options(skb->dev, rs_msg->opt, ndoptlen, &ndopts)) { 1142 ND_PRINTK(2, notice, "NS: invalid ND option, ignored\n"); 1143 goto out; 1144 } 1145 1146 if (ndopts.nd_opts_src_lladdr) { 1147 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr, 1148 skb->dev); 1149 if (!lladdr) 1150 goto out; 1151 } 1152 1153 neigh = __neigh_lookup(&nd_tbl, saddr, skb->dev, 1); 1154 if (neigh) { 1155 ndisc_update(skb->dev, neigh, lladdr, NUD_STALE, 1156 NEIGH_UPDATE_F_WEAK_OVERRIDE| 1157 NEIGH_UPDATE_F_OVERRIDE| 1158 NEIGH_UPDATE_F_OVERRIDE_ISROUTER, 1159 NDISC_ROUTER_SOLICITATION, &ndopts); 1160 neigh_release(neigh); 1161 } 1162 out: 1163 return; 1164 } 1165 1166 static void ndisc_ra_useropt(struct sk_buff *ra, struct nd_opt_hdr *opt) 1167 { 1168 struct icmp6hdr *icmp6h = (struct icmp6hdr *)skb_transport_header(ra); 1169 struct sk_buff *skb; 1170 struct nlmsghdr *nlh; 1171 struct nduseroptmsg *ndmsg; 1172 struct net *net = dev_net(ra->dev); 1173 int err; 1174 int base_size = NLMSG_ALIGN(sizeof(struct nduseroptmsg) 1175 + (opt->nd_opt_len << 3)); 1176 size_t msg_size = base_size + nla_total_size(sizeof(struct in6_addr)); 1177 1178 skb = nlmsg_new(msg_size, GFP_ATOMIC); 1179 if (!skb) { 1180 err = -ENOBUFS; 1181 goto errout; 1182 } 1183 1184 nlh = nlmsg_put(skb, 0, 0, RTM_NEWNDUSEROPT, base_size, 0); 1185 if (!nlh) { 1186 goto nla_put_failure; 1187 } 1188 1189 ndmsg = nlmsg_data(nlh); 1190 ndmsg->nduseropt_family = AF_INET6; 1191 ndmsg->nduseropt_ifindex = ra->dev->ifindex; 1192 ndmsg->nduseropt_icmp_type = icmp6h->icmp6_type; 1193 ndmsg->nduseropt_icmp_code = icmp6h->icmp6_code; 1194 ndmsg->nduseropt_opts_len = opt->nd_opt_len << 3; 1195 1196 memcpy(ndmsg + 1, opt, opt->nd_opt_len << 3); 1197 1198 if (nla_put_in6_addr(skb, NDUSEROPT_SRCADDR, &ipv6_hdr(ra)->saddr)) 1199 goto nla_put_failure; 1200 nlmsg_end(skb, nlh); 1201 1202 rtnl_notify(skb, net, 0, RTNLGRP_ND_USEROPT, NULL, GFP_ATOMIC); 1203 return; 1204 1205 nla_put_failure: 1206 nlmsg_free(skb); 1207 err = -EMSGSIZE; 1208 errout: 1209 rtnl_set_sk_err(net, RTNLGRP_ND_USEROPT, err); 1210 } 1211 1212 static void ndisc_router_discovery(struct sk_buff *skb) 1213 { 1214 struct ra_msg *ra_msg = (struct ra_msg *)skb_transport_header(skb); 1215 struct neighbour *neigh = NULL; 1216 struct inet6_dev *in6_dev; 1217 struct fib6_info *rt = NULL; 1218 u32 defrtr_usr_metric; 1219 struct net *net; 1220 int lifetime; 1221 struct ndisc_options ndopts; 1222 int optlen; 1223 unsigned int pref = 0; 1224 __u32 old_if_flags; 1225 bool send_ifinfo_notify = false; 1226 1227 __u8 *opt = (__u8 *)(ra_msg + 1); 1228 1229 optlen = (skb_tail_pointer(skb) - skb_transport_header(skb)) - 1230 sizeof(struct ra_msg); 1231 1232 ND_PRINTK(2, info, 1233 "RA: %s, dev: %s\n", 1234 __func__, skb->dev->name); 1235 if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) { 1236 ND_PRINTK(2, warn, "RA: source address is not link-local\n"); 1237 return; 1238 } 1239 if (optlen < 0) { 1240 ND_PRINTK(2, warn, "RA: packet too short\n"); 1241 return; 1242 } 1243 1244 #ifdef CONFIG_IPV6_NDISC_NODETYPE 1245 if (skb->ndisc_nodetype == NDISC_NODETYPE_HOST) { 1246 ND_PRINTK(2, warn, "RA: from host or unauthorized router\n"); 1247 return; 1248 } 1249 #endif 1250 1251 /* 1252 * set the RA_RECV flag in the interface 1253 */ 1254 1255 in6_dev = __in6_dev_get(skb->dev); 1256 if (!in6_dev) { 1257 ND_PRINTK(0, err, "RA: can't find inet6 device for %s\n", 1258 skb->dev->name); 1259 return; 1260 } 1261 1262 if (!ndisc_parse_options(skb->dev, opt, optlen, &ndopts)) { 1263 ND_PRINTK(2, warn, "RA: invalid ND options\n"); 1264 return; 1265 } 1266 1267 if (!ipv6_accept_ra(in6_dev)) { 1268 ND_PRINTK(2, info, 1269 "RA: %s, did not accept ra for dev: %s\n", 1270 __func__, skb->dev->name); 1271 goto skip_linkparms; 1272 } 1273 1274 #ifdef CONFIG_IPV6_NDISC_NODETYPE 1275 /* skip link-specific parameters from interior routers */ 1276 if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT) { 1277 ND_PRINTK(2, info, 1278 "RA: %s, nodetype is NODEFAULT, dev: %s\n", 1279 __func__, skb->dev->name); 1280 goto skip_linkparms; 1281 } 1282 #endif 1283 1284 if (in6_dev->if_flags & IF_RS_SENT) { 1285 /* 1286 * flag that an RA was received after an RS was sent 1287 * out on this interface. 1288 */ 1289 in6_dev->if_flags |= IF_RA_RCVD; 1290 } 1291 1292 /* 1293 * Remember the managed/otherconf flags from most recently 1294 * received RA message (RFC 2462) -- yoshfuji 1295 */ 1296 old_if_flags = in6_dev->if_flags; 1297 in6_dev->if_flags = (in6_dev->if_flags & ~(IF_RA_MANAGED | 1298 IF_RA_OTHERCONF)) | 1299 (ra_msg->icmph.icmp6_addrconf_managed ? 1300 IF_RA_MANAGED : 0) | 1301 (ra_msg->icmph.icmp6_addrconf_other ? 1302 IF_RA_OTHERCONF : 0); 1303 1304 if (old_if_flags != in6_dev->if_flags) 1305 send_ifinfo_notify = true; 1306 1307 if (!in6_dev->cnf.accept_ra_defrtr) { 1308 ND_PRINTK(2, info, 1309 "RA: %s, defrtr is false for dev: %s\n", 1310 __func__, skb->dev->name); 1311 goto skip_defrtr; 1312 } 1313 1314 /* Do not accept RA with source-addr found on local machine unless 1315 * accept_ra_from_local is set to true. 1316 */ 1317 net = dev_net(in6_dev->dev); 1318 if (!in6_dev->cnf.accept_ra_from_local && 1319 ipv6_chk_addr(net, &ipv6_hdr(skb)->saddr, in6_dev->dev, 0)) { 1320 ND_PRINTK(2, info, 1321 "RA from local address detected on dev: %s: default router ignored\n", 1322 skb->dev->name); 1323 goto skip_defrtr; 1324 } 1325 1326 lifetime = ntohs(ra_msg->icmph.icmp6_rt_lifetime); 1327 1328 #ifdef CONFIG_IPV6_ROUTER_PREF 1329 pref = ra_msg->icmph.icmp6_router_pref; 1330 /* 10b is handled as if it were 00b (medium) */ 1331 if (pref == ICMPV6_ROUTER_PREF_INVALID || 1332 !in6_dev->cnf.accept_ra_rtr_pref) 1333 pref = ICMPV6_ROUTER_PREF_MEDIUM; 1334 #endif 1335 /* routes added from RAs do not use nexthop objects */ 1336 rt = rt6_get_dflt_router(net, &ipv6_hdr(skb)->saddr, skb->dev); 1337 if (rt) { 1338 neigh = ip6_neigh_lookup(&rt->fib6_nh->fib_nh_gw6, 1339 rt->fib6_nh->fib_nh_dev, NULL, 1340 &ipv6_hdr(skb)->saddr); 1341 if (!neigh) { 1342 ND_PRINTK(0, err, 1343 "RA: %s got default router without neighbour\n", 1344 __func__); 1345 fib6_info_release(rt); 1346 return; 1347 } 1348 } 1349 /* Set default route metric as specified by user */ 1350 defrtr_usr_metric = in6_dev->cnf.ra_defrtr_metric; 1351 /* delete the route if lifetime is 0 or if metric needs change */ 1352 if (rt && (lifetime == 0 || rt->fib6_metric != defrtr_usr_metric)) { 1353 ip6_del_rt(net, rt, false); 1354 rt = NULL; 1355 } 1356 1357 ND_PRINTK(3, info, "RA: rt: %p lifetime: %d, metric: %d, for dev: %s\n", 1358 rt, lifetime, defrtr_usr_metric, skb->dev->name); 1359 if (!rt && lifetime) { 1360 ND_PRINTK(3, info, "RA: adding default router\n"); 1361 1362 rt = rt6_add_dflt_router(net, &ipv6_hdr(skb)->saddr, 1363 skb->dev, pref, defrtr_usr_metric); 1364 if (!rt) { 1365 ND_PRINTK(0, err, 1366 "RA: %s failed to add default route\n", 1367 __func__); 1368 return; 1369 } 1370 1371 neigh = ip6_neigh_lookup(&rt->fib6_nh->fib_nh_gw6, 1372 rt->fib6_nh->fib_nh_dev, NULL, 1373 &ipv6_hdr(skb)->saddr); 1374 if (!neigh) { 1375 ND_PRINTK(0, err, 1376 "RA: %s got default router without neighbour\n", 1377 __func__); 1378 fib6_info_release(rt); 1379 return; 1380 } 1381 neigh->flags |= NTF_ROUTER; 1382 } else if (rt && IPV6_EXTRACT_PREF(rt->fib6_flags) != pref) { 1383 struct nl_info nlinfo = { 1384 .nl_net = net, 1385 }; 1386 rt->fib6_flags = (rt->fib6_flags & ~RTF_PREF_MASK) | RTF_PREF(pref); 1387 inet6_rt_notify(RTM_NEWROUTE, rt, &nlinfo, NLM_F_REPLACE); 1388 } 1389 1390 if (rt) 1391 fib6_set_expires(rt, jiffies + (HZ * lifetime)); 1392 if (in6_dev->cnf.accept_ra_min_hop_limit < 256 && 1393 ra_msg->icmph.icmp6_hop_limit) { 1394 if (in6_dev->cnf.accept_ra_min_hop_limit <= ra_msg->icmph.icmp6_hop_limit) { 1395 in6_dev->cnf.hop_limit = ra_msg->icmph.icmp6_hop_limit; 1396 fib6_metric_set(rt, RTAX_HOPLIMIT, 1397 ra_msg->icmph.icmp6_hop_limit); 1398 } else { 1399 ND_PRINTK(2, warn, "RA: Got route advertisement with lower hop_limit than minimum\n"); 1400 } 1401 } 1402 1403 skip_defrtr: 1404 1405 /* 1406 * Update Reachable Time and Retrans Timer 1407 */ 1408 1409 if (in6_dev->nd_parms) { 1410 unsigned long rtime = ntohl(ra_msg->retrans_timer); 1411 1412 if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/HZ) { 1413 rtime = (rtime*HZ)/1000; 1414 if (rtime < HZ/100) 1415 rtime = HZ/100; 1416 NEIGH_VAR_SET(in6_dev->nd_parms, RETRANS_TIME, rtime); 1417 in6_dev->tstamp = jiffies; 1418 send_ifinfo_notify = true; 1419 } 1420 1421 rtime = ntohl(ra_msg->reachable_time); 1422 if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/(3*HZ)) { 1423 rtime = (rtime*HZ)/1000; 1424 1425 if (rtime < HZ/10) 1426 rtime = HZ/10; 1427 1428 if (rtime != NEIGH_VAR(in6_dev->nd_parms, BASE_REACHABLE_TIME)) { 1429 NEIGH_VAR_SET(in6_dev->nd_parms, 1430 BASE_REACHABLE_TIME, rtime); 1431 NEIGH_VAR_SET(in6_dev->nd_parms, 1432 GC_STALETIME, 3 * rtime); 1433 in6_dev->nd_parms->reachable_time = neigh_rand_reach_time(rtime); 1434 in6_dev->tstamp = jiffies; 1435 send_ifinfo_notify = true; 1436 } 1437 } 1438 } 1439 1440 skip_linkparms: 1441 1442 /* 1443 * Process options. 1444 */ 1445 1446 if (!neigh) 1447 neigh = __neigh_lookup(&nd_tbl, &ipv6_hdr(skb)->saddr, 1448 skb->dev, 1); 1449 if (neigh) { 1450 u8 *lladdr = NULL; 1451 if (ndopts.nd_opts_src_lladdr) { 1452 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr, 1453 skb->dev); 1454 if (!lladdr) { 1455 ND_PRINTK(2, warn, 1456 "RA: invalid link-layer address length\n"); 1457 goto out; 1458 } 1459 } 1460 ndisc_update(skb->dev, neigh, lladdr, NUD_STALE, 1461 NEIGH_UPDATE_F_WEAK_OVERRIDE| 1462 NEIGH_UPDATE_F_OVERRIDE| 1463 NEIGH_UPDATE_F_OVERRIDE_ISROUTER| 1464 NEIGH_UPDATE_F_ISROUTER, 1465 NDISC_ROUTER_ADVERTISEMENT, &ndopts); 1466 } 1467 1468 if (!ipv6_accept_ra(in6_dev)) { 1469 ND_PRINTK(2, info, 1470 "RA: %s, accept_ra is false for dev: %s\n", 1471 __func__, skb->dev->name); 1472 goto out; 1473 } 1474 1475 #ifdef CONFIG_IPV6_ROUTE_INFO 1476 if (!in6_dev->cnf.accept_ra_from_local && 1477 ipv6_chk_addr(dev_net(in6_dev->dev), &ipv6_hdr(skb)->saddr, 1478 in6_dev->dev, 0)) { 1479 ND_PRINTK(2, info, 1480 "RA from local address detected on dev: %s: router info ignored.\n", 1481 skb->dev->name); 1482 goto skip_routeinfo; 1483 } 1484 1485 if (in6_dev->cnf.accept_ra_rtr_pref && ndopts.nd_opts_ri) { 1486 struct nd_opt_hdr *p; 1487 for (p = ndopts.nd_opts_ri; 1488 p; 1489 p = ndisc_next_option(p, ndopts.nd_opts_ri_end)) { 1490 struct route_info *ri = (struct route_info *)p; 1491 #ifdef CONFIG_IPV6_NDISC_NODETYPE 1492 if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT && 1493 ri->prefix_len == 0) 1494 continue; 1495 #endif 1496 if (ri->prefix_len == 0 && 1497 !in6_dev->cnf.accept_ra_defrtr) 1498 continue; 1499 if (ri->prefix_len < in6_dev->cnf.accept_ra_rt_info_min_plen) 1500 continue; 1501 if (ri->prefix_len > in6_dev->cnf.accept_ra_rt_info_max_plen) 1502 continue; 1503 rt6_route_rcv(skb->dev, (u8 *)p, (p->nd_opt_len) << 3, 1504 &ipv6_hdr(skb)->saddr); 1505 } 1506 } 1507 1508 skip_routeinfo: 1509 #endif 1510 1511 #ifdef CONFIG_IPV6_NDISC_NODETYPE 1512 /* skip link-specific ndopts from interior routers */ 1513 if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT) { 1514 ND_PRINTK(2, info, 1515 "RA: %s, nodetype is NODEFAULT (interior routes), dev: %s\n", 1516 __func__, skb->dev->name); 1517 goto out; 1518 } 1519 #endif 1520 1521 if (in6_dev->cnf.accept_ra_pinfo && ndopts.nd_opts_pi) { 1522 struct nd_opt_hdr *p; 1523 for (p = ndopts.nd_opts_pi; 1524 p; 1525 p = ndisc_next_option(p, ndopts.nd_opts_pi_end)) { 1526 addrconf_prefix_rcv(skb->dev, (u8 *)p, 1527 (p->nd_opt_len) << 3, 1528 ndopts.nd_opts_src_lladdr != NULL); 1529 } 1530 } 1531 1532 if (ndopts.nd_opts_mtu && in6_dev->cnf.accept_ra_mtu) { 1533 __be32 n; 1534 u32 mtu; 1535 1536 memcpy(&n, ((u8 *)(ndopts.nd_opts_mtu+1))+2, sizeof(mtu)); 1537 mtu = ntohl(n); 1538 1539 if (in6_dev->ra_mtu != mtu) { 1540 in6_dev->ra_mtu = mtu; 1541 send_ifinfo_notify = true; 1542 } 1543 1544 if (mtu < IPV6_MIN_MTU || mtu > skb->dev->mtu) { 1545 ND_PRINTK(2, warn, "RA: invalid mtu: %d\n", mtu); 1546 } else if (in6_dev->cnf.mtu6 != mtu) { 1547 in6_dev->cnf.mtu6 = mtu; 1548 fib6_metric_set(rt, RTAX_MTU, mtu); 1549 rt6_mtu_change(skb->dev, mtu); 1550 } 1551 } 1552 1553 if (ndopts.nd_useropts) { 1554 struct nd_opt_hdr *p; 1555 for (p = ndopts.nd_useropts; 1556 p; 1557 p = ndisc_next_useropt(skb->dev, p, 1558 ndopts.nd_useropts_end)) { 1559 ndisc_ra_useropt(skb, p); 1560 } 1561 } 1562 1563 if (ndopts.nd_opts_tgt_lladdr || ndopts.nd_opts_rh) { 1564 ND_PRINTK(2, warn, "RA: invalid RA options\n"); 1565 } 1566 out: 1567 /* Send a notify if RA changed managed/otherconf flags or 1568 * timer settings or ra_mtu value 1569 */ 1570 if (send_ifinfo_notify) 1571 inet6_ifinfo_notify(RTM_NEWLINK, in6_dev); 1572 1573 fib6_info_release(rt); 1574 if (neigh) 1575 neigh_release(neigh); 1576 } 1577 1578 static void ndisc_redirect_rcv(struct sk_buff *skb) 1579 { 1580 u8 *hdr; 1581 struct ndisc_options ndopts; 1582 struct rd_msg *msg = (struct rd_msg *)skb_transport_header(skb); 1583 u32 ndoptlen = skb_tail_pointer(skb) - (skb_transport_header(skb) + 1584 offsetof(struct rd_msg, opt)); 1585 1586 #ifdef CONFIG_IPV6_NDISC_NODETYPE 1587 switch (skb->ndisc_nodetype) { 1588 case NDISC_NODETYPE_HOST: 1589 case NDISC_NODETYPE_NODEFAULT: 1590 ND_PRINTK(2, warn, 1591 "Redirect: from host or unauthorized router\n"); 1592 return; 1593 } 1594 #endif 1595 1596 if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) { 1597 ND_PRINTK(2, warn, 1598 "Redirect: source address is not link-local\n"); 1599 return; 1600 } 1601 1602 if (!ndisc_parse_options(skb->dev, msg->opt, ndoptlen, &ndopts)) 1603 return; 1604 1605 if (!ndopts.nd_opts_rh) { 1606 ip6_redirect_no_header(skb, dev_net(skb->dev), 1607 skb->dev->ifindex); 1608 return; 1609 } 1610 1611 hdr = (u8 *)ndopts.nd_opts_rh; 1612 hdr += 8; 1613 if (!pskb_pull(skb, hdr - skb_transport_header(skb))) 1614 return; 1615 1616 icmpv6_notify(skb, NDISC_REDIRECT, 0, 0); 1617 } 1618 1619 static void ndisc_fill_redirect_hdr_option(struct sk_buff *skb, 1620 struct sk_buff *orig_skb, 1621 int rd_len) 1622 { 1623 u8 *opt = skb_put(skb, rd_len); 1624 1625 memset(opt, 0, 8); 1626 *(opt++) = ND_OPT_REDIRECT_HDR; 1627 *(opt++) = (rd_len >> 3); 1628 opt += 6; 1629 1630 skb_copy_bits(orig_skb, skb_network_offset(orig_skb), opt, 1631 rd_len - 8); 1632 } 1633 1634 void ndisc_send_redirect(struct sk_buff *skb, const struct in6_addr *target) 1635 { 1636 struct net_device *dev = skb->dev; 1637 struct net *net = dev_net(dev); 1638 struct sock *sk = net->ipv6.ndisc_sk; 1639 int optlen = 0; 1640 struct inet_peer *peer; 1641 struct sk_buff *buff; 1642 struct rd_msg *msg; 1643 struct in6_addr saddr_buf; 1644 struct rt6_info *rt; 1645 struct dst_entry *dst; 1646 struct flowi6 fl6; 1647 int rd_len; 1648 u8 ha_buf[MAX_ADDR_LEN], *ha = NULL, 1649 ops_data_buf[NDISC_OPS_REDIRECT_DATA_SPACE], *ops_data = NULL; 1650 bool ret; 1651 1652 if (netif_is_l3_master(skb->dev)) { 1653 dev = __dev_get_by_index(dev_net(skb->dev), IPCB(skb)->iif); 1654 if (!dev) 1655 return; 1656 } 1657 1658 if (ipv6_get_lladdr(dev, &saddr_buf, IFA_F_TENTATIVE)) { 1659 ND_PRINTK(2, warn, "Redirect: no link-local address on %s\n", 1660 dev->name); 1661 return; 1662 } 1663 1664 if (!ipv6_addr_equal(&ipv6_hdr(skb)->daddr, target) && 1665 ipv6_addr_type(target) != (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) { 1666 ND_PRINTK(2, warn, 1667 "Redirect: target address is not link-local unicast\n"); 1668 return; 1669 } 1670 1671 icmpv6_flow_init(sk, &fl6, NDISC_REDIRECT, 1672 &saddr_buf, &ipv6_hdr(skb)->saddr, dev->ifindex); 1673 1674 dst = ip6_route_output(net, NULL, &fl6); 1675 if (dst->error) { 1676 dst_release(dst); 1677 return; 1678 } 1679 dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), NULL, 0); 1680 if (IS_ERR(dst)) 1681 return; 1682 1683 rt = (struct rt6_info *) dst; 1684 1685 if (rt->rt6i_flags & RTF_GATEWAY) { 1686 ND_PRINTK(2, warn, 1687 "Redirect: destination is not a neighbour\n"); 1688 goto release; 1689 } 1690 peer = inet_getpeer_v6(net->ipv6.peers, &ipv6_hdr(skb)->saddr, 1); 1691 ret = inet_peer_xrlim_allow(peer, 1*HZ); 1692 if (peer) 1693 inet_putpeer(peer); 1694 if (!ret) 1695 goto release; 1696 1697 if (dev->addr_len) { 1698 struct neighbour *neigh = dst_neigh_lookup(skb_dst(skb), target); 1699 if (!neigh) { 1700 ND_PRINTK(2, warn, 1701 "Redirect: no neigh for target address\n"); 1702 goto release; 1703 } 1704 1705 read_lock_bh(&neigh->lock); 1706 if (neigh->nud_state & NUD_VALID) { 1707 memcpy(ha_buf, neigh->ha, dev->addr_len); 1708 read_unlock_bh(&neigh->lock); 1709 ha = ha_buf; 1710 optlen += ndisc_redirect_opt_addr_space(dev, neigh, 1711 ops_data_buf, 1712 &ops_data); 1713 } else 1714 read_unlock_bh(&neigh->lock); 1715 1716 neigh_release(neigh); 1717 } 1718 1719 rd_len = min_t(unsigned int, 1720 IPV6_MIN_MTU - sizeof(struct ipv6hdr) - sizeof(*msg) - optlen, 1721 skb->len + 8); 1722 rd_len &= ~0x7; 1723 optlen += rd_len; 1724 1725 buff = ndisc_alloc_skb(dev, sizeof(*msg) + optlen); 1726 if (!buff) 1727 goto release; 1728 1729 msg = skb_put(buff, sizeof(*msg)); 1730 *msg = (struct rd_msg) { 1731 .icmph = { 1732 .icmp6_type = NDISC_REDIRECT, 1733 }, 1734 .target = *target, 1735 .dest = ipv6_hdr(skb)->daddr, 1736 }; 1737 1738 /* 1739 * include target_address option 1740 */ 1741 1742 if (ha) 1743 ndisc_fill_redirect_addr_option(buff, ha, ops_data); 1744 1745 /* 1746 * build redirect option and copy skb over to the new packet. 1747 */ 1748 1749 if (rd_len) 1750 ndisc_fill_redirect_hdr_option(buff, skb, rd_len); 1751 1752 skb_dst_set(buff, dst); 1753 ndisc_send_skb(buff, &ipv6_hdr(skb)->saddr, &saddr_buf); 1754 return; 1755 1756 release: 1757 dst_release(dst); 1758 } 1759 1760 static void pndisc_redo(struct sk_buff *skb) 1761 { 1762 ndisc_recv_ns(skb); 1763 kfree_skb(skb); 1764 } 1765 1766 static int ndisc_is_multicast(const void *pkey) 1767 { 1768 return ipv6_addr_is_multicast((struct in6_addr *)pkey); 1769 } 1770 1771 static bool ndisc_suppress_frag_ndisc(struct sk_buff *skb) 1772 { 1773 struct inet6_dev *idev = __in6_dev_get(skb->dev); 1774 1775 if (!idev) 1776 return true; 1777 if (IP6CB(skb)->flags & IP6SKB_FRAGMENTED && 1778 idev->cnf.suppress_frag_ndisc) { 1779 net_warn_ratelimited("Received fragmented ndisc packet. Carefully consider disabling suppress_frag_ndisc.\n"); 1780 return true; 1781 } 1782 return false; 1783 } 1784 1785 int ndisc_rcv(struct sk_buff *skb) 1786 { 1787 struct nd_msg *msg; 1788 1789 if (ndisc_suppress_frag_ndisc(skb)) 1790 return 0; 1791 1792 if (skb_linearize(skb)) 1793 return 0; 1794 1795 msg = (struct nd_msg *)skb_transport_header(skb); 1796 1797 __skb_push(skb, skb->data - skb_transport_header(skb)); 1798 1799 if (ipv6_hdr(skb)->hop_limit != 255) { 1800 ND_PRINTK(2, warn, "NDISC: invalid hop-limit: %d\n", 1801 ipv6_hdr(skb)->hop_limit); 1802 return 0; 1803 } 1804 1805 if (msg->icmph.icmp6_code != 0) { 1806 ND_PRINTK(2, warn, "NDISC: invalid ICMPv6 code: %d\n", 1807 msg->icmph.icmp6_code); 1808 return 0; 1809 } 1810 1811 switch (msg->icmph.icmp6_type) { 1812 case NDISC_NEIGHBOUR_SOLICITATION: 1813 memset(NEIGH_CB(skb), 0, sizeof(struct neighbour_cb)); 1814 ndisc_recv_ns(skb); 1815 break; 1816 1817 case NDISC_NEIGHBOUR_ADVERTISEMENT: 1818 ndisc_recv_na(skb); 1819 break; 1820 1821 case NDISC_ROUTER_SOLICITATION: 1822 ndisc_recv_rs(skb); 1823 break; 1824 1825 case NDISC_ROUTER_ADVERTISEMENT: 1826 ndisc_router_discovery(skb); 1827 break; 1828 1829 case NDISC_REDIRECT: 1830 ndisc_redirect_rcv(skb); 1831 break; 1832 } 1833 1834 return 0; 1835 } 1836 1837 static int ndisc_netdev_event(struct notifier_block *this, unsigned long event, void *ptr) 1838 { 1839 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 1840 struct netdev_notifier_change_info *change_info; 1841 struct net *net = dev_net(dev); 1842 struct inet6_dev *idev; 1843 bool evict_nocarrier; 1844 1845 switch (event) { 1846 case NETDEV_CHANGEADDR: 1847 neigh_changeaddr(&nd_tbl, dev); 1848 fib6_run_gc(0, net, false); 1849 fallthrough; 1850 case NETDEV_UP: 1851 idev = in6_dev_get(dev); 1852 if (!idev) 1853 break; 1854 if (idev->cnf.ndisc_notify || 1855 net->ipv6.devconf_all->ndisc_notify) 1856 ndisc_send_unsol_na(dev); 1857 in6_dev_put(idev); 1858 break; 1859 case NETDEV_CHANGE: 1860 idev = in6_dev_get(dev); 1861 if (!idev) 1862 evict_nocarrier = true; 1863 else { 1864 evict_nocarrier = idev->cnf.ndisc_evict_nocarrier && 1865 net->ipv6.devconf_all->ndisc_evict_nocarrier; 1866 in6_dev_put(idev); 1867 } 1868 1869 change_info = ptr; 1870 if (change_info->flags_changed & IFF_NOARP) 1871 neigh_changeaddr(&nd_tbl, dev); 1872 if (evict_nocarrier && !netif_carrier_ok(dev)) 1873 neigh_carrier_down(&nd_tbl, dev); 1874 break; 1875 case NETDEV_DOWN: 1876 neigh_ifdown(&nd_tbl, dev); 1877 fib6_run_gc(0, net, false); 1878 break; 1879 case NETDEV_NOTIFY_PEERS: 1880 ndisc_send_unsol_na(dev); 1881 break; 1882 default: 1883 break; 1884 } 1885 1886 return NOTIFY_DONE; 1887 } 1888 1889 static struct notifier_block ndisc_netdev_notifier = { 1890 .notifier_call = ndisc_netdev_event, 1891 .priority = ADDRCONF_NOTIFY_PRIORITY - 5, 1892 }; 1893 1894 #ifdef CONFIG_SYSCTL 1895 static void ndisc_warn_deprecated_sysctl(struct ctl_table *ctl, 1896 const char *func, const char *dev_name) 1897 { 1898 static char warncomm[TASK_COMM_LEN]; 1899 static int warned; 1900 if (strcmp(warncomm, current->comm) && warned < 5) { 1901 strcpy(warncomm, current->comm); 1902 pr_warn("process `%s' is using deprecated sysctl (%s) net.ipv6.neigh.%s.%s - use net.ipv6.neigh.%s.%s_ms instead\n", 1903 warncomm, func, 1904 dev_name, ctl->procname, 1905 dev_name, ctl->procname); 1906 warned++; 1907 } 1908 } 1909 1910 int ndisc_ifinfo_sysctl_change(struct ctl_table *ctl, int write, void *buffer, 1911 size_t *lenp, loff_t *ppos) 1912 { 1913 struct net_device *dev = ctl->extra1; 1914 struct inet6_dev *idev; 1915 int ret; 1916 1917 if ((strcmp(ctl->procname, "retrans_time") == 0) || 1918 (strcmp(ctl->procname, "base_reachable_time") == 0)) 1919 ndisc_warn_deprecated_sysctl(ctl, "syscall", dev ? dev->name : "default"); 1920 1921 if (strcmp(ctl->procname, "retrans_time") == 0) 1922 ret = neigh_proc_dointvec(ctl, write, buffer, lenp, ppos); 1923 1924 else if (strcmp(ctl->procname, "base_reachable_time") == 0) 1925 ret = neigh_proc_dointvec_jiffies(ctl, write, 1926 buffer, lenp, ppos); 1927 1928 else if ((strcmp(ctl->procname, "retrans_time_ms") == 0) || 1929 (strcmp(ctl->procname, "base_reachable_time_ms") == 0)) 1930 ret = neigh_proc_dointvec_ms_jiffies(ctl, write, 1931 buffer, lenp, ppos); 1932 else 1933 ret = -1; 1934 1935 if (write && ret == 0 && dev && (idev = in6_dev_get(dev)) != NULL) { 1936 if (ctl->data == &NEIGH_VAR(idev->nd_parms, BASE_REACHABLE_TIME)) 1937 idev->nd_parms->reachable_time = 1938 neigh_rand_reach_time(NEIGH_VAR(idev->nd_parms, BASE_REACHABLE_TIME)); 1939 idev->tstamp = jiffies; 1940 inet6_ifinfo_notify(RTM_NEWLINK, idev); 1941 in6_dev_put(idev); 1942 } 1943 return ret; 1944 } 1945 1946 1947 #endif 1948 1949 static int __net_init ndisc_net_init(struct net *net) 1950 { 1951 struct ipv6_pinfo *np; 1952 struct sock *sk; 1953 int err; 1954 1955 err = inet_ctl_sock_create(&sk, PF_INET6, 1956 SOCK_RAW, IPPROTO_ICMPV6, net); 1957 if (err < 0) { 1958 ND_PRINTK(0, err, 1959 "NDISC: Failed to initialize the control socket (err %d)\n", 1960 err); 1961 return err; 1962 } 1963 1964 net->ipv6.ndisc_sk = sk; 1965 1966 np = inet6_sk(sk); 1967 np->hop_limit = 255; 1968 /* Do not loopback ndisc messages */ 1969 np->mc_loop = 0; 1970 1971 return 0; 1972 } 1973 1974 static void __net_exit ndisc_net_exit(struct net *net) 1975 { 1976 inet_ctl_sock_destroy(net->ipv6.ndisc_sk); 1977 } 1978 1979 static struct pernet_operations ndisc_net_ops = { 1980 .init = ndisc_net_init, 1981 .exit = ndisc_net_exit, 1982 }; 1983 1984 int __init ndisc_init(void) 1985 { 1986 int err; 1987 1988 err = register_pernet_subsys(&ndisc_net_ops); 1989 if (err) 1990 return err; 1991 /* 1992 * Initialize the neighbour table 1993 */ 1994 neigh_table_init(NEIGH_ND_TABLE, &nd_tbl); 1995 1996 #ifdef CONFIG_SYSCTL 1997 err = neigh_sysctl_register(NULL, &nd_tbl.parms, 1998 ndisc_ifinfo_sysctl_change); 1999 if (err) 2000 goto out_unregister_pernet; 2001 out: 2002 #endif 2003 return err; 2004 2005 #ifdef CONFIG_SYSCTL 2006 out_unregister_pernet: 2007 unregister_pernet_subsys(&ndisc_net_ops); 2008 goto out; 2009 #endif 2010 } 2011 2012 int __init ndisc_late_init(void) 2013 { 2014 return register_netdevice_notifier(&ndisc_netdev_notifier); 2015 } 2016 2017 void ndisc_late_cleanup(void) 2018 { 2019 unregister_netdevice_notifier(&ndisc_netdev_notifier); 2020 } 2021 2022 void ndisc_cleanup(void) 2023 { 2024 #ifdef CONFIG_SYSCTL 2025 neigh_sysctl_unregister(&nd_tbl.parms); 2026 #endif 2027 neigh_table_clear(NEIGH_ND_TABLE, &nd_tbl); 2028 unregister_pernet_subsys(&ndisc_net_ops); 2029 } 2030