| 1 | /* |
| 2 | * Neighbour Discovery for IPv6 |
| 3 | * Linux INET6 implementation |
| 4 | * |
| 5 | * Authors: |
| 6 | * Pedro Roque <roque@di.fc.ul.pt> |
| 7 | * Mike Shaver <shaver@ingenia.com> |
| 8 | * |
| 9 | * This program is free software; you can redistribute it and/or |
| 10 | * modify it under the terms of the GNU General Public License |
| 11 | * as published by the Free Software Foundation; either version |
| 12 | * 2 of the License, or (at your option) any later version. |
| 13 | */ |
| 14 | |
| 15 | /* |
| 16 | * Changes: |
| 17 | * |
| 18 | * Alexey I. Froloff : RFC6106 (DNSSL) support |
| 19 | * Pierre Ynard : export userland ND options |
| 20 | * through netlink (RDNSS support) |
| 21 | * Lars Fenneberg : fixed MTU setting on receipt |
| 22 | * of an RA. |
| 23 | * Janos Farkas : kmalloc failure checks |
| 24 | * Alexey Kuznetsov : state machine reworked |
| 25 | * and moved to net/core. |
| 26 | * Pekka Savola : RFC2461 validation |
| 27 | * YOSHIFUJI Hideaki @USAGI : Verify ND options properly |
| 28 | */ |
| 29 | |
| 30 | #define pr_fmt(fmt) "ICMPv6: " fmt |
| 31 | |
| 32 | #include <linux/module.h> |
| 33 | #include <linux/errno.h> |
| 34 | #include <linux/types.h> |
| 35 | #include <linux/socket.h> |
| 36 | #include <linux/sockios.h> |
| 37 | #include <linux/sched.h> |
| 38 | #include <linux/net.h> |
| 39 | #include <linux/in6.h> |
| 40 | #include <linux/route.h> |
| 41 | #include <linux/init.h> |
| 42 | #include <linux/rcupdate.h> |
| 43 | #include <linux/slab.h> |
| 44 | #ifdef CONFIG_SYSCTL |
| 45 | #include <linux/sysctl.h> |
| 46 | #endif |
| 47 | |
| 48 | #include <linux/if_addr.h> |
| 49 | #include <linux/if_arp.h> |
| 50 | #include <linux/ipv6.h> |
| 51 | #include <linux/icmpv6.h> |
| 52 | #include <linux/jhash.h> |
| 53 | |
| 54 | #include <net/sock.h> |
| 55 | #include <net/snmp.h> |
| 56 | |
| 57 | #include <net/ipv6.h> |
| 58 | #include <net/protocol.h> |
| 59 | #include <net/ndisc.h> |
| 60 | #include <net/ip6_route.h> |
| 61 | #include <net/addrconf.h> |
| 62 | #include <net/icmp.h> |
| 63 | |
| 64 | #include <net/netlink.h> |
| 65 | #include <linux/rtnetlink.h> |
| 66 | |
| 67 | #include <net/flow.h> |
| 68 | #include <net/ip6_checksum.h> |
| 69 | #include <net/inet_common.h> |
| 70 | #include <linux/proc_fs.h> |
| 71 | |
| 72 | #include <linux/netfilter.h> |
| 73 | #include <linux/netfilter_ipv6.h> |
| 74 | |
| 75 | /* Set to 3 to get tracing... */ |
| 76 | #define ND_DEBUG 1 |
| 77 | |
| 78 | #define ND_PRINTK(val, level, fmt, ...) \ |
| 79 | do { \ |
| 80 | if (val <= ND_DEBUG) \ |
| 81 | net_##level##_ratelimited(fmt, ##__VA_ARGS__); \ |
| 82 | } while (0) |
| 83 | |
| 84 | static u32 ndisc_hash(const void *pkey, |
| 85 | const struct net_device *dev, |
| 86 | __u32 *hash_rnd); |
| 87 | static int ndisc_constructor(struct neighbour *neigh); |
| 88 | static void ndisc_solicit(struct neighbour *neigh, struct sk_buff *skb); |
| 89 | static void ndisc_error_report(struct neighbour *neigh, struct sk_buff *skb); |
| 90 | static int pndisc_constructor(struct pneigh_entry *n); |
| 91 | static void pndisc_destructor(struct pneigh_entry *n); |
| 92 | static void pndisc_redo(struct sk_buff *skb); |
| 93 | |
| 94 | static const struct neigh_ops ndisc_generic_ops = { |
| 95 | .family = AF_INET6, |
| 96 | .solicit = ndisc_solicit, |
| 97 | .error_report = ndisc_error_report, |
| 98 | .output = neigh_resolve_output, |
| 99 | .connected_output = neigh_connected_output, |
| 100 | }; |
| 101 | |
| 102 | static const struct neigh_ops ndisc_hh_ops = { |
| 103 | .family = AF_INET6, |
| 104 | .solicit = ndisc_solicit, |
| 105 | .error_report = ndisc_error_report, |
| 106 | .output = neigh_resolve_output, |
| 107 | .connected_output = neigh_resolve_output, |
| 108 | }; |
| 109 | |
| 110 | |
| 111 | static const struct neigh_ops ndisc_direct_ops = { |
| 112 | .family = AF_INET6, |
| 113 | .output = neigh_direct_output, |
| 114 | .connected_output = neigh_direct_output, |
| 115 | }; |
| 116 | |
| 117 | struct neigh_table nd_tbl = { |
| 118 | .family = AF_INET6, |
| 119 | .key_len = sizeof(struct in6_addr), |
| 120 | .hash = ndisc_hash, |
| 121 | .constructor = ndisc_constructor, |
| 122 | .pconstructor = pndisc_constructor, |
| 123 | .pdestructor = pndisc_destructor, |
| 124 | .proxy_redo = pndisc_redo, |
| 125 | .id = "ndisc_cache", |
| 126 | .parms = { |
| 127 | .tbl = &nd_tbl, |
| 128 | .base_reachable_time = ND_REACHABLE_TIME, |
| 129 | .retrans_time = ND_RETRANS_TIMER, |
| 130 | .gc_staletime = 60 * HZ, |
| 131 | .reachable_time = ND_REACHABLE_TIME, |
| 132 | .delay_probe_time = 5 * HZ, |
| 133 | .queue_len_bytes = 64*1024, |
| 134 | .ucast_probes = 3, |
| 135 | .mcast_probes = 3, |
| 136 | .anycast_delay = 1 * HZ, |
| 137 | .proxy_delay = (8 * HZ) / 10, |
| 138 | .proxy_qlen = 64, |
| 139 | }, |
| 140 | .gc_interval = 30 * HZ, |
| 141 | .gc_thresh1 = 128, |
| 142 | .gc_thresh2 = 512, |
| 143 | .gc_thresh3 = 1024, |
| 144 | }; |
| 145 | |
| 146 | static void ndisc_fill_addr_option(struct sk_buff *skb, int type, void *data) |
| 147 | { |
| 148 | int pad = ndisc_addr_option_pad(skb->dev->type); |
| 149 | int data_len = skb->dev->addr_len; |
| 150 | int space = ndisc_opt_addr_space(skb->dev); |
| 151 | u8 *opt = skb_put(skb, space); |
| 152 | |
| 153 | opt[0] = type; |
| 154 | opt[1] = space>>3; |
| 155 | |
| 156 | memset(opt + 2, 0, pad); |
| 157 | opt += pad; |
| 158 | space -= pad; |
| 159 | |
| 160 | memcpy(opt+2, data, data_len); |
| 161 | data_len += 2; |
| 162 | opt += data_len; |
| 163 | if ((space -= data_len) > 0) |
| 164 | memset(opt, 0, space); |
| 165 | } |
| 166 | |
| 167 | static struct nd_opt_hdr *ndisc_next_option(struct nd_opt_hdr *cur, |
| 168 | struct nd_opt_hdr *end) |
| 169 | { |
| 170 | int type; |
| 171 | if (!cur || !end || cur >= end) |
| 172 | return NULL; |
| 173 | type = cur->nd_opt_type; |
| 174 | do { |
| 175 | cur = ((void *)cur) + (cur->nd_opt_len << 3); |
| 176 | } while(cur < end && cur->nd_opt_type != type); |
| 177 | return cur <= end && cur->nd_opt_type == type ? cur : NULL; |
| 178 | } |
| 179 | |
| 180 | static inline int ndisc_is_useropt(struct nd_opt_hdr *opt) |
| 181 | { |
| 182 | return opt->nd_opt_type == ND_OPT_RDNSS || |
| 183 | opt->nd_opt_type == ND_OPT_DNSSL; |
| 184 | } |
| 185 | |
| 186 | static struct nd_opt_hdr *ndisc_next_useropt(struct nd_opt_hdr *cur, |
| 187 | struct nd_opt_hdr *end) |
| 188 | { |
| 189 | if (!cur || !end || cur >= end) |
| 190 | return NULL; |
| 191 | do { |
| 192 | cur = ((void *)cur) + (cur->nd_opt_len << 3); |
| 193 | } while(cur < end && !ndisc_is_useropt(cur)); |
| 194 | return cur <= end && ndisc_is_useropt(cur) ? cur : NULL; |
| 195 | } |
| 196 | |
| 197 | struct ndisc_options *ndisc_parse_options(u8 *opt, int opt_len, |
| 198 | struct ndisc_options *ndopts) |
| 199 | { |
| 200 | struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)opt; |
| 201 | |
| 202 | if (!nd_opt || opt_len < 0 || !ndopts) |
| 203 | return NULL; |
| 204 | memset(ndopts, 0, sizeof(*ndopts)); |
| 205 | while (opt_len) { |
| 206 | int l; |
| 207 | if (opt_len < sizeof(struct nd_opt_hdr)) |
| 208 | return NULL; |
| 209 | l = nd_opt->nd_opt_len << 3; |
| 210 | if (opt_len < l || l == 0) |
| 211 | return NULL; |
| 212 | switch (nd_opt->nd_opt_type) { |
| 213 | case ND_OPT_SOURCE_LL_ADDR: |
| 214 | case ND_OPT_TARGET_LL_ADDR: |
| 215 | case ND_OPT_MTU: |
| 216 | case ND_OPT_REDIRECT_HDR: |
| 217 | if (ndopts->nd_opt_array[nd_opt->nd_opt_type]) { |
| 218 | ND_PRINTK(2, warn, |
| 219 | "%s: duplicated ND6 option found: type=%d\n", |
| 220 | __func__, nd_opt->nd_opt_type); |
| 221 | } else { |
| 222 | ndopts->nd_opt_array[nd_opt->nd_opt_type] = nd_opt; |
| 223 | } |
| 224 | break; |
| 225 | case ND_OPT_PREFIX_INFO: |
| 226 | ndopts->nd_opts_pi_end = nd_opt; |
| 227 | if (!ndopts->nd_opt_array[nd_opt->nd_opt_type]) |
| 228 | ndopts->nd_opt_array[nd_opt->nd_opt_type] = nd_opt; |
| 229 | break; |
| 230 | #ifdef CONFIG_IPV6_ROUTE_INFO |
| 231 | case ND_OPT_ROUTE_INFO: |
| 232 | ndopts->nd_opts_ri_end = nd_opt; |
| 233 | if (!ndopts->nd_opts_ri) |
| 234 | ndopts->nd_opts_ri = nd_opt; |
| 235 | break; |
| 236 | #endif |
| 237 | default: |
| 238 | if (ndisc_is_useropt(nd_opt)) { |
| 239 | ndopts->nd_useropts_end = nd_opt; |
| 240 | if (!ndopts->nd_useropts) |
| 241 | ndopts->nd_useropts = nd_opt; |
| 242 | } else { |
| 243 | /* |
| 244 | * Unknown options must be silently ignored, |
| 245 | * to accommodate future extension to the |
| 246 | * protocol. |
| 247 | */ |
| 248 | ND_PRINTK(2, notice, |
| 249 | "%s: ignored unsupported option; type=%d, len=%d\n", |
| 250 | __func__, |
| 251 | nd_opt->nd_opt_type, |
| 252 | nd_opt->nd_opt_len); |
| 253 | } |
| 254 | } |
| 255 | opt_len -= l; |
| 256 | nd_opt = ((void *)nd_opt) + l; |
| 257 | } |
| 258 | return ndopts; |
| 259 | } |
| 260 | |
| 261 | int ndisc_mc_map(const struct in6_addr *addr, char *buf, struct net_device *dev, int dir) |
| 262 | { |
| 263 | switch (dev->type) { |
| 264 | case ARPHRD_ETHER: |
| 265 | case ARPHRD_IEEE802: /* Not sure. Check it later. --ANK */ |
| 266 | case ARPHRD_FDDI: |
| 267 | ipv6_eth_mc_map(addr, buf); |
| 268 | return 0; |
| 269 | case ARPHRD_ARCNET: |
| 270 | ipv6_arcnet_mc_map(addr, buf); |
| 271 | return 0; |
| 272 | case ARPHRD_INFINIBAND: |
| 273 | ipv6_ib_mc_map(addr, dev->broadcast, buf); |
| 274 | return 0; |
| 275 | case ARPHRD_IPGRE: |
| 276 | return ipv6_ipgre_mc_map(addr, dev->broadcast, buf); |
| 277 | default: |
| 278 | if (dir) { |
| 279 | memcpy(buf, dev->broadcast, dev->addr_len); |
| 280 | return 0; |
| 281 | } |
| 282 | } |
| 283 | return -EINVAL; |
| 284 | } |
| 285 | |
| 286 | EXPORT_SYMBOL(ndisc_mc_map); |
| 287 | |
| 288 | static u32 ndisc_hash(const void *pkey, |
| 289 | const struct net_device *dev, |
| 290 | __u32 *hash_rnd) |
| 291 | { |
| 292 | return ndisc_hashfn(pkey, dev, hash_rnd); |
| 293 | } |
| 294 | |
| 295 | static int ndisc_constructor(struct neighbour *neigh) |
| 296 | { |
| 297 | struct in6_addr *addr = (struct in6_addr*)&neigh->primary_key; |
| 298 | struct net_device *dev = neigh->dev; |
| 299 | struct inet6_dev *in6_dev; |
| 300 | struct neigh_parms *parms; |
| 301 | bool is_multicast = ipv6_addr_is_multicast(addr); |
| 302 | |
| 303 | in6_dev = in6_dev_get(dev); |
| 304 | if (in6_dev == NULL) { |
| 305 | return -EINVAL; |
| 306 | } |
| 307 | |
| 308 | parms = in6_dev->nd_parms; |
| 309 | __neigh_parms_put(neigh->parms); |
| 310 | neigh->parms = neigh_parms_clone(parms); |
| 311 | |
| 312 | neigh->type = is_multicast ? RTN_MULTICAST : RTN_UNICAST; |
| 313 | if (!dev->header_ops) { |
| 314 | neigh->nud_state = NUD_NOARP; |
| 315 | neigh->ops = &ndisc_direct_ops; |
| 316 | neigh->output = neigh_direct_output; |
| 317 | } else { |
| 318 | if (is_multicast) { |
| 319 | neigh->nud_state = NUD_NOARP; |
| 320 | ndisc_mc_map(addr, neigh->ha, dev, 1); |
| 321 | } else if (dev->flags&(IFF_NOARP|IFF_LOOPBACK)) { |
| 322 | neigh->nud_state = NUD_NOARP; |
| 323 | memcpy(neigh->ha, dev->dev_addr, dev->addr_len); |
| 324 | if (dev->flags&IFF_LOOPBACK) |
| 325 | neigh->type = RTN_LOCAL; |
| 326 | } else if (dev->flags&IFF_POINTOPOINT) { |
| 327 | neigh->nud_state = NUD_NOARP; |
| 328 | memcpy(neigh->ha, dev->broadcast, dev->addr_len); |
| 329 | } |
| 330 | if (dev->header_ops->cache) |
| 331 | neigh->ops = &ndisc_hh_ops; |
| 332 | else |
| 333 | neigh->ops = &ndisc_generic_ops; |
| 334 | if (neigh->nud_state&NUD_VALID) |
| 335 | neigh->output = neigh->ops->connected_output; |
| 336 | else |
| 337 | neigh->output = neigh->ops->output; |
| 338 | } |
| 339 | in6_dev_put(in6_dev); |
| 340 | return 0; |
| 341 | } |
| 342 | |
| 343 | static int pndisc_constructor(struct pneigh_entry *n) |
| 344 | { |
| 345 | struct in6_addr *addr = (struct in6_addr*)&n->key; |
| 346 | struct in6_addr maddr; |
| 347 | struct net_device *dev = n->dev; |
| 348 | |
| 349 | if (dev == NULL || __in6_dev_get(dev) == NULL) |
| 350 | return -EINVAL; |
| 351 | addrconf_addr_solict_mult(addr, &maddr); |
| 352 | ipv6_dev_mc_inc(dev, &maddr); |
| 353 | return 0; |
| 354 | } |
| 355 | |
| 356 | static void pndisc_destructor(struct pneigh_entry *n) |
| 357 | { |
| 358 | struct in6_addr *addr = (struct in6_addr*)&n->key; |
| 359 | struct in6_addr maddr; |
| 360 | struct net_device *dev = n->dev; |
| 361 | |
| 362 | if (dev == NULL || __in6_dev_get(dev) == NULL) |
| 363 | return; |
| 364 | addrconf_addr_solict_mult(addr, &maddr); |
| 365 | ipv6_dev_mc_dec(dev, &maddr); |
| 366 | } |
| 367 | |
| 368 | static struct sk_buff *ndisc_alloc_skb(struct net_device *dev, |
| 369 | int len) |
| 370 | { |
| 371 | int hlen = LL_RESERVED_SPACE(dev); |
| 372 | int tlen = dev->needed_tailroom; |
| 373 | struct sock *sk = dev_net(dev)->ipv6.ndisc_sk; |
| 374 | struct sk_buff *skb; |
| 375 | |
| 376 | skb = alloc_skb(hlen + sizeof(struct ipv6hdr) + len + tlen, GFP_ATOMIC); |
| 377 | if (!skb) { |
| 378 | ND_PRINTK(0, err, "ndisc: %s failed to allocate an skb\n", |
| 379 | __func__); |
| 380 | return NULL; |
| 381 | } |
| 382 | |
| 383 | skb->protocol = htons(ETH_P_IPV6); |
| 384 | skb->dev = dev; |
| 385 | |
| 386 | skb_reserve(skb, hlen + sizeof(struct ipv6hdr)); |
| 387 | skb_reset_transport_header(skb); |
| 388 | |
| 389 | /* Manually assign socket ownership as we avoid calling |
| 390 | * sock_alloc_send_pskb() to bypass wmem buffer limits |
| 391 | */ |
| 392 | skb_set_owner_w(skb, sk); |
| 393 | |
| 394 | return skb; |
| 395 | } |
| 396 | |
| 397 | static void ip6_nd_hdr(struct sk_buff *skb, |
| 398 | const struct in6_addr *saddr, |
| 399 | const struct in6_addr *daddr, |
| 400 | int hop_limit, int len) |
| 401 | { |
| 402 | struct ipv6hdr *hdr; |
| 403 | |
| 404 | skb_push(skb, sizeof(*hdr)); |
| 405 | skb_reset_network_header(skb); |
| 406 | hdr = ipv6_hdr(skb); |
| 407 | |
| 408 | ip6_flow_hdr(hdr, 0, 0); |
| 409 | |
| 410 | hdr->payload_len = htons(len); |
| 411 | hdr->nexthdr = IPPROTO_ICMPV6; |
| 412 | hdr->hop_limit = hop_limit; |
| 413 | |
| 414 | hdr->saddr = *saddr; |
| 415 | hdr->daddr = *daddr; |
| 416 | } |
| 417 | |
| 418 | static void ndisc_send_skb(struct sk_buff *skb, |
| 419 | const struct in6_addr *daddr, |
| 420 | const struct in6_addr *saddr) |
| 421 | { |
| 422 | struct dst_entry *dst = skb_dst(skb); |
| 423 | struct net *net = dev_net(skb->dev); |
| 424 | struct sock *sk = net->ipv6.ndisc_sk; |
| 425 | struct inet6_dev *idev; |
| 426 | int err; |
| 427 | struct icmp6hdr *icmp6h = icmp6_hdr(skb); |
| 428 | u8 type; |
| 429 | |
| 430 | type = icmp6h->icmp6_type; |
| 431 | |
| 432 | if (!dst) { |
| 433 | struct sock *sk = net->ipv6.ndisc_sk; |
| 434 | struct flowi6 fl6; |
| 435 | |
| 436 | icmpv6_flow_init(sk, &fl6, type, saddr, daddr, skb->dev->ifindex); |
| 437 | dst = icmp6_dst_alloc(skb->dev, &fl6); |
| 438 | if (IS_ERR(dst)) { |
| 439 | kfree_skb(skb); |
| 440 | return; |
| 441 | } |
| 442 | |
| 443 | skb_dst_set(skb, dst); |
| 444 | } |
| 445 | |
| 446 | icmp6h->icmp6_cksum = csum_ipv6_magic(saddr, daddr, skb->len, |
| 447 | IPPROTO_ICMPV6, |
| 448 | csum_partial(icmp6h, |
| 449 | skb->len, 0)); |
| 450 | |
| 451 | ip6_nd_hdr(skb, saddr, daddr, inet6_sk(sk)->hop_limit, skb->len); |
| 452 | |
| 453 | rcu_read_lock(); |
| 454 | idev = __in6_dev_get(dst->dev); |
| 455 | IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUT, skb->len); |
| 456 | |
| 457 | err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT, skb, NULL, dst->dev, |
| 458 | dst_output); |
| 459 | if (!err) { |
| 460 | ICMP6MSGOUT_INC_STATS(net, idev, type); |
| 461 | ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS); |
| 462 | } |
| 463 | |
| 464 | rcu_read_unlock(); |
| 465 | } |
| 466 | |
| 467 | static void ndisc_send_na(struct net_device *dev, struct neighbour *neigh, |
| 468 | const struct in6_addr *daddr, |
| 469 | const struct in6_addr *solicited_addr, |
| 470 | bool router, bool solicited, bool override, bool inc_opt) |
| 471 | { |
| 472 | struct sk_buff *skb; |
| 473 | struct in6_addr tmpaddr; |
| 474 | struct inet6_ifaddr *ifp; |
| 475 | const struct in6_addr *src_addr; |
| 476 | struct nd_msg *msg; |
| 477 | int optlen = 0; |
| 478 | |
| 479 | /* for anycast or proxy, solicited_addr != src_addr */ |
| 480 | ifp = ipv6_get_ifaddr(dev_net(dev), solicited_addr, dev, 1); |
| 481 | if (ifp) { |
| 482 | src_addr = solicited_addr; |
| 483 | if (ifp->flags & IFA_F_OPTIMISTIC) |
| 484 | override = 0; |
| 485 | inc_opt |= ifp->idev->cnf.force_tllao; |
| 486 | in6_ifa_put(ifp); |
| 487 | } else { |
| 488 | if (ipv6_dev_get_saddr(dev_net(dev), dev, daddr, |
| 489 | inet6_sk(dev_net(dev)->ipv6.ndisc_sk)->srcprefs, |
| 490 | &tmpaddr)) |
| 491 | return; |
| 492 | src_addr = &tmpaddr; |
| 493 | } |
| 494 | |
| 495 | if (!dev->addr_len) |
| 496 | inc_opt = 0; |
| 497 | if (inc_opt) |
| 498 | optlen += ndisc_opt_addr_space(dev); |
| 499 | |
| 500 | skb = ndisc_alloc_skb(dev, sizeof(*msg) + optlen); |
| 501 | if (!skb) |
| 502 | return; |
| 503 | |
| 504 | msg = (struct nd_msg *)skb_put(skb, sizeof(*msg)); |
| 505 | *msg = (struct nd_msg) { |
| 506 | .icmph = { |
| 507 | .icmp6_type = NDISC_NEIGHBOUR_ADVERTISEMENT, |
| 508 | .icmp6_router = router, |
| 509 | .icmp6_solicited = solicited, |
| 510 | .icmp6_override = override, |
| 511 | }, |
| 512 | .target = *solicited_addr, |
| 513 | }; |
| 514 | |
| 515 | if (inc_opt) |
| 516 | ndisc_fill_addr_option(skb, ND_OPT_TARGET_LL_ADDR, |
| 517 | dev->dev_addr); |
| 518 | |
| 519 | |
| 520 | ndisc_send_skb(skb, daddr, src_addr); |
| 521 | } |
| 522 | |
| 523 | static void ndisc_send_unsol_na(struct net_device *dev) |
| 524 | { |
| 525 | struct inet6_dev *idev; |
| 526 | struct inet6_ifaddr *ifa; |
| 527 | |
| 528 | idev = in6_dev_get(dev); |
| 529 | if (!idev) |
| 530 | return; |
| 531 | |
| 532 | read_lock_bh(&idev->lock); |
| 533 | list_for_each_entry(ifa, &idev->addr_list, if_list) { |
| 534 | ndisc_send_na(dev, NULL, &in6addr_linklocal_allnodes, &ifa->addr, |
| 535 | /*router=*/ !!idev->cnf.forwarding, |
| 536 | /*solicited=*/ false, /*override=*/ true, |
| 537 | /*inc_opt=*/ true); |
| 538 | } |
| 539 | read_unlock_bh(&idev->lock); |
| 540 | |
| 541 | in6_dev_put(idev); |
| 542 | } |
| 543 | |
| 544 | void ndisc_send_ns(struct net_device *dev, struct neighbour *neigh, |
| 545 | const struct in6_addr *solicit, |
| 546 | const struct in6_addr *daddr, const struct in6_addr *saddr) |
| 547 | { |
| 548 | struct sk_buff *skb; |
| 549 | struct in6_addr addr_buf; |
| 550 | int inc_opt = dev->addr_len; |
| 551 | int optlen = 0; |
| 552 | struct nd_msg *msg; |
| 553 | |
| 554 | if (saddr == NULL) { |
| 555 | if (ipv6_get_lladdr(dev, &addr_buf, |
| 556 | (IFA_F_TENTATIVE|IFA_F_OPTIMISTIC))) |
| 557 | return; |
| 558 | saddr = &addr_buf; |
| 559 | } |
| 560 | |
| 561 | if (ipv6_addr_any(saddr)) |
| 562 | inc_opt = 0; |
| 563 | if (inc_opt) |
| 564 | optlen += ndisc_opt_addr_space(dev); |
| 565 | |
| 566 | skb = ndisc_alloc_skb(dev, sizeof(*msg) + optlen); |
| 567 | if (!skb) |
| 568 | return; |
| 569 | |
| 570 | msg = (struct nd_msg *)skb_put(skb, sizeof(*msg)); |
| 571 | *msg = (struct nd_msg) { |
| 572 | .icmph = { |
| 573 | .icmp6_type = NDISC_NEIGHBOUR_SOLICITATION, |
| 574 | }, |
| 575 | .target = *solicit, |
| 576 | }; |
| 577 | |
| 578 | if (inc_opt) |
| 579 | ndisc_fill_addr_option(skb, ND_OPT_SOURCE_LL_ADDR, |
| 580 | dev->dev_addr); |
| 581 | |
| 582 | ndisc_send_skb(skb, daddr, saddr); |
| 583 | } |
| 584 | |
| 585 | void ndisc_send_rs(struct net_device *dev, const struct in6_addr *saddr, |
| 586 | const struct in6_addr *daddr) |
| 587 | { |
| 588 | struct sk_buff *skb; |
| 589 | struct rs_msg *msg; |
| 590 | int send_sllao = dev->addr_len; |
| 591 | int optlen = 0; |
| 592 | |
| 593 | #ifdef CONFIG_IPV6_OPTIMISTIC_DAD |
| 594 | /* |
| 595 | * According to section 2.2 of RFC 4429, we must not |
| 596 | * send router solicitations with a sllao from |
| 597 | * optimistic addresses, but we may send the solicitation |
| 598 | * if we don't include the sllao. So here we check |
| 599 | * if our address is optimistic, and if so, we |
| 600 | * suppress the inclusion of the sllao. |
| 601 | */ |
| 602 | if (send_sllao) { |
| 603 | struct inet6_ifaddr *ifp = ipv6_get_ifaddr(dev_net(dev), saddr, |
| 604 | dev, 1); |
| 605 | if (ifp) { |
| 606 | if (ifp->flags & IFA_F_OPTIMISTIC) { |
| 607 | send_sllao = 0; |
| 608 | } |
| 609 | in6_ifa_put(ifp); |
| 610 | } else { |
| 611 | send_sllao = 0; |
| 612 | } |
| 613 | } |
| 614 | #endif |
| 615 | if (send_sllao) |
| 616 | optlen += ndisc_opt_addr_space(dev); |
| 617 | |
| 618 | skb = ndisc_alloc_skb(dev, sizeof(*msg) + optlen); |
| 619 | if (!skb) |
| 620 | return; |
| 621 | |
| 622 | msg = (struct rs_msg *)skb_put(skb, sizeof(*msg)); |
| 623 | *msg = (struct rs_msg) { |
| 624 | .icmph = { |
| 625 | .icmp6_type = NDISC_ROUTER_SOLICITATION, |
| 626 | }, |
| 627 | }; |
| 628 | |
| 629 | if (send_sllao) |
| 630 | ndisc_fill_addr_option(skb, ND_OPT_SOURCE_LL_ADDR, |
| 631 | dev->dev_addr); |
| 632 | |
| 633 | ndisc_send_skb(skb, daddr, saddr); |
| 634 | } |
| 635 | |
| 636 | |
| 637 | static void ndisc_error_report(struct neighbour *neigh, struct sk_buff *skb) |
| 638 | { |
| 639 | /* |
| 640 | * "The sender MUST return an ICMP |
| 641 | * destination unreachable" |
| 642 | */ |
| 643 | dst_link_failure(skb); |
| 644 | kfree_skb(skb); |
| 645 | } |
| 646 | |
| 647 | /* Called with locked neigh: either read or both */ |
| 648 | |
| 649 | static void ndisc_solicit(struct neighbour *neigh, struct sk_buff *skb) |
| 650 | { |
| 651 | struct in6_addr *saddr = NULL; |
| 652 | struct in6_addr mcaddr; |
| 653 | struct net_device *dev = neigh->dev; |
| 654 | struct in6_addr *target = (struct in6_addr *)&neigh->primary_key; |
| 655 | int probes = atomic_read(&neigh->probes); |
| 656 | |
| 657 | if (skb && ipv6_chk_addr(dev_net(dev), &ipv6_hdr(skb)->saddr, dev, 1)) |
| 658 | saddr = &ipv6_hdr(skb)->saddr; |
| 659 | |
| 660 | if ((probes -= neigh->parms->ucast_probes) < 0) { |
| 661 | if (!(neigh->nud_state & NUD_VALID)) { |
| 662 | ND_PRINTK(1, dbg, |
| 663 | "%s: trying to ucast probe in NUD_INVALID: %pI6\n", |
| 664 | __func__, target); |
| 665 | } |
| 666 | ndisc_send_ns(dev, neigh, target, target, saddr); |
| 667 | } else if ((probes -= neigh->parms->app_probes) < 0) { |
| 668 | #ifdef CONFIG_ARPD |
| 669 | neigh_app_ns(neigh); |
| 670 | #endif |
| 671 | } else { |
| 672 | addrconf_addr_solict_mult(target, &mcaddr); |
| 673 | ndisc_send_ns(dev, NULL, target, &mcaddr, saddr); |
| 674 | } |
| 675 | } |
| 676 | |
| 677 | static int pndisc_is_router(const void *pkey, |
| 678 | struct net_device *dev) |
| 679 | { |
| 680 | struct pneigh_entry *n; |
| 681 | int ret = -1; |
| 682 | |
| 683 | read_lock_bh(&nd_tbl.lock); |
| 684 | n = __pneigh_lookup(&nd_tbl, dev_net(dev), pkey, dev); |
| 685 | if (n) |
| 686 | ret = !!(n->flags & NTF_ROUTER); |
| 687 | read_unlock_bh(&nd_tbl.lock); |
| 688 | |
| 689 | return ret; |
| 690 | } |
| 691 | |
| 692 | static void ndisc_recv_ns(struct sk_buff *skb) |
| 693 | { |
| 694 | struct nd_msg *msg = (struct nd_msg *)skb_transport_header(skb); |
| 695 | const struct in6_addr *saddr = &ipv6_hdr(skb)->saddr; |
| 696 | const struct in6_addr *daddr = &ipv6_hdr(skb)->daddr; |
| 697 | u8 *lladdr = NULL; |
| 698 | u32 ndoptlen = skb->tail - (skb->transport_header + |
| 699 | offsetof(struct nd_msg, opt)); |
| 700 | struct ndisc_options ndopts; |
| 701 | struct net_device *dev = skb->dev; |
| 702 | struct inet6_ifaddr *ifp; |
| 703 | struct inet6_dev *idev = NULL; |
| 704 | struct neighbour *neigh; |
| 705 | int dad = ipv6_addr_any(saddr); |
| 706 | bool inc; |
| 707 | int is_router = -1; |
| 708 | |
| 709 | if (skb->len < sizeof(struct nd_msg)) { |
| 710 | ND_PRINTK(2, warn, "NS: packet too short\n"); |
| 711 | return; |
| 712 | } |
| 713 | |
| 714 | if (ipv6_addr_is_multicast(&msg->target)) { |
| 715 | ND_PRINTK(2, warn, "NS: multicast target address\n"); |
| 716 | return; |
| 717 | } |
| 718 | |
| 719 | /* |
| 720 | * RFC2461 7.1.1: |
| 721 | * DAD has to be destined for solicited node multicast address. |
| 722 | */ |
| 723 | if (dad && !ipv6_addr_is_solict_mult(daddr)) { |
| 724 | ND_PRINTK(2, warn, "NS: bad DAD packet (wrong destination)\n"); |
| 725 | return; |
| 726 | } |
| 727 | |
| 728 | if (!ndisc_parse_options(msg->opt, ndoptlen, &ndopts)) { |
| 729 | ND_PRINTK(2, warn, "NS: invalid ND options\n"); |
| 730 | return; |
| 731 | } |
| 732 | |
| 733 | if (ndopts.nd_opts_src_lladdr) { |
| 734 | lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr, dev); |
| 735 | if (!lladdr) { |
| 736 | ND_PRINTK(2, warn, |
| 737 | "NS: invalid link-layer address length\n"); |
| 738 | return; |
| 739 | } |
| 740 | |
| 741 | /* RFC2461 7.1.1: |
| 742 | * If the IP source address is the unspecified address, |
| 743 | * there MUST NOT be source link-layer address option |
| 744 | * in the message. |
| 745 | */ |
| 746 | if (dad) { |
| 747 | ND_PRINTK(2, warn, |
| 748 | "NS: bad DAD packet (link-layer address option)\n"); |
| 749 | return; |
| 750 | } |
| 751 | } |
| 752 | |
| 753 | inc = ipv6_addr_is_multicast(daddr); |
| 754 | |
| 755 | ifp = ipv6_get_ifaddr(dev_net(dev), &msg->target, dev, 1); |
| 756 | if (ifp) { |
| 757 | |
| 758 | if (ifp->flags & (IFA_F_TENTATIVE|IFA_F_OPTIMISTIC)) { |
| 759 | if (dad) { |
| 760 | /* |
| 761 | * We are colliding with another node |
| 762 | * who is doing DAD |
| 763 | * so fail our DAD process |
| 764 | */ |
| 765 | addrconf_dad_failure(ifp); |
| 766 | return; |
| 767 | } else { |
| 768 | /* |
| 769 | * This is not a dad solicitation. |
| 770 | * If we are an optimistic node, |
| 771 | * we should respond. |
| 772 | * Otherwise, we should ignore it. |
| 773 | */ |
| 774 | if (!(ifp->flags & IFA_F_OPTIMISTIC)) |
| 775 | goto out; |
| 776 | } |
| 777 | } |
| 778 | |
| 779 | idev = ifp->idev; |
| 780 | } else { |
| 781 | struct net *net = dev_net(dev); |
| 782 | |
| 783 | idev = in6_dev_get(dev); |
| 784 | if (!idev) { |
| 785 | /* XXX: count this drop? */ |
| 786 | return; |
| 787 | } |
| 788 | |
| 789 | if (ipv6_chk_acast_addr(net, dev, &msg->target) || |
| 790 | (idev->cnf.forwarding && |
| 791 | (net->ipv6.devconf_all->proxy_ndp || idev->cnf.proxy_ndp) && |
| 792 | (is_router = pndisc_is_router(&msg->target, dev)) >= 0)) { |
| 793 | if (!(NEIGH_CB(skb)->flags & LOCALLY_ENQUEUED) && |
| 794 | skb->pkt_type != PACKET_HOST && |
| 795 | inc != 0 && |
| 796 | idev->nd_parms->proxy_delay != 0) { |
| 797 | /* |
| 798 | * for anycast or proxy, |
| 799 | * sender should delay its response |
| 800 | * by a random time between 0 and |
| 801 | * MAX_ANYCAST_DELAY_TIME seconds. |
| 802 | * (RFC2461) -- yoshfuji |
| 803 | */ |
| 804 | struct sk_buff *n = skb_clone(skb, GFP_ATOMIC); |
| 805 | if (n) |
| 806 | pneigh_enqueue(&nd_tbl, idev->nd_parms, n); |
| 807 | goto out; |
| 808 | } |
| 809 | } else |
| 810 | goto out; |
| 811 | } |
| 812 | |
| 813 | if (is_router < 0) |
| 814 | is_router = idev->cnf.forwarding; |
| 815 | |
| 816 | if (dad) { |
| 817 | ndisc_send_na(dev, NULL, &in6addr_linklocal_allnodes, &msg->target, |
| 818 | !!is_router, false, (ifp != NULL), true); |
| 819 | goto out; |
| 820 | } |
| 821 | |
| 822 | if (inc) |
| 823 | NEIGH_CACHE_STAT_INC(&nd_tbl, rcv_probes_mcast); |
| 824 | else |
| 825 | NEIGH_CACHE_STAT_INC(&nd_tbl, rcv_probes_ucast); |
| 826 | |
| 827 | /* |
| 828 | * update / create cache entry |
| 829 | * for the source address |
| 830 | */ |
| 831 | neigh = __neigh_lookup(&nd_tbl, saddr, dev, |
| 832 | !inc || lladdr || !dev->addr_len); |
| 833 | if (neigh) |
| 834 | neigh_update(neigh, lladdr, NUD_STALE, |
| 835 | NEIGH_UPDATE_F_WEAK_OVERRIDE| |
| 836 | NEIGH_UPDATE_F_OVERRIDE); |
| 837 | if (neigh || !dev->header_ops) { |
| 838 | ndisc_send_na(dev, neigh, saddr, &msg->target, |
| 839 | !!is_router, |
| 840 | true, (ifp != NULL && inc), inc); |
| 841 | if (neigh) |
| 842 | neigh_release(neigh); |
| 843 | } |
| 844 | |
| 845 | out: |
| 846 | if (ifp) |
| 847 | in6_ifa_put(ifp); |
| 848 | else |
| 849 | in6_dev_put(idev); |
| 850 | } |
| 851 | |
| 852 | static void ndisc_recv_na(struct sk_buff *skb) |
| 853 | { |
| 854 | struct nd_msg *msg = (struct nd_msg *)skb_transport_header(skb); |
| 855 | const struct in6_addr *saddr = &ipv6_hdr(skb)->saddr; |
| 856 | const struct in6_addr *daddr = &ipv6_hdr(skb)->daddr; |
| 857 | u8 *lladdr = NULL; |
| 858 | u32 ndoptlen = skb->tail - (skb->transport_header + |
| 859 | offsetof(struct nd_msg, opt)); |
| 860 | struct ndisc_options ndopts; |
| 861 | struct net_device *dev = skb->dev; |
| 862 | struct inet6_ifaddr *ifp; |
| 863 | struct neighbour *neigh; |
| 864 | |
| 865 | if (skb->len < sizeof(struct nd_msg)) { |
| 866 | ND_PRINTK(2, warn, "NA: packet too short\n"); |
| 867 | return; |
| 868 | } |
| 869 | |
| 870 | if (ipv6_addr_is_multicast(&msg->target)) { |
| 871 | ND_PRINTK(2, warn, "NA: target address is multicast\n"); |
| 872 | return; |
| 873 | } |
| 874 | |
| 875 | if (ipv6_addr_is_multicast(daddr) && |
| 876 | msg->icmph.icmp6_solicited) { |
| 877 | ND_PRINTK(2, warn, "NA: solicited NA is multicasted\n"); |
| 878 | return; |
| 879 | } |
| 880 | |
| 881 | if (!ndisc_parse_options(msg->opt, ndoptlen, &ndopts)) { |
| 882 | ND_PRINTK(2, warn, "NS: invalid ND option\n"); |
| 883 | return; |
| 884 | } |
| 885 | if (ndopts.nd_opts_tgt_lladdr) { |
| 886 | lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr, dev); |
| 887 | if (!lladdr) { |
| 888 | ND_PRINTK(2, warn, |
| 889 | "NA: invalid link-layer address length\n"); |
| 890 | return; |
| 891 | } |
| 892 | } |
| 893 | ifp = ipv6_get_ifaddr(dev_net(dev), &msg->target, dev, 1); |
| 894 | if (ifp) { |
| 895 | if (skb->pkt_type != PACKET_LOOPBACK |
| 896 | && (ifp->flags & IFA_F_TENTATIVE)) { |
| 897 | addrconf_dad_failure(ifp); |
| 898 | return; |
| 899 | } |
| 900 | /* What should we make now? The advertisement |
| 901 | is invalid, but ndisc specs say nothing |
| 902 | about it. It could be misconfiguration, or |
| 903 | an smart proxy agent tries to help us :-) |
| 904 | |
| 905 | We should not print the error if NA has been |
| 906 | received from loopback - it is just our own |
| 907 | unsolicited advertisement. |
| 908 | */ |
| 909 | if (skb->pkt_type != PACKET_LOOPBACK) |
| 910 | ND_PRINTK(1, warn, |
| 911 | "NA: someone advertises our address %pI6 on %s!\n", |
| 912 | &ifp->addr, ifp->idev->dev->name); |
| 913 | in6_ifa_put(ifp); |
| 914 | return; |
| 915 | } |
| 916 | neigh = neigh_lookup(&nd_tbl, &msg->target, dev); |
| 917 | |
| 918 | if (neigh) { |
| 919 | u8 old_flags = neigh->flags; |
| 920 | struct net *net = dev_net(dev); |
| 921 | |
| 922 | if (neigh->nud_state & NUD_FAILED) |
| 923 | goto out; |
| 924 | |
| 925 | /* |
| 926 | * Don't update the neighbor cache entry on a proxy NA from |
| 927 | * ourselves because either the proxied node is off link or it |
| 928 | * has already sent a NA to us. |
| 929 | */ |
| 930 | if (lladdr && !memcmp(lladdr, dev->dev_addr, dev->addr_len) && |
| 931 | net->ipv6.devconf_all->forwarding && net->ipv6.devconf_all->proxy_ndp && |
| 932 | pneigh_lookup(&nd_tbl, net, &msg->target, dev, 0)) { |
| 933 | /* XXX: idev->cnf.proxy_ndp */ |
| 934 | goto out; |
| 935 | } |
| 936 | |
| 937 | neigh_update(neigh, lladdr, |
| 938 | msg->icmph.icmp6_solicited ? NUD_REACHABLE : NUD_STALE, |
| 939 | NEIGH_UPDATE_F_WEAK_OVERRIDE| |
| 940 | (msg->icmph.icmp6_override ? NEIGH_UPDATE_F_OVERRIDE : 0)| |
| 941 | NEIGH_UPDATE_F_OVERRIDE_ISROUTER| |
| 942 | (msg->icmph.icmp6_router ? NEIGH_UPDATE_F_ISROUTER : 0)); |
| 943 | |
| 944 | if ((old_flags & ~neigh->flags) & NTF_ROUTER) { |
| 945 | /* |
| 946 | * Change: router to host |
| 947 | */ |
| 948 | struct rt6_info *rt; |
| 949 | rt = rt6_get_dflt_router(saddr, dev); |
| 950 | if (rt) |
| 951 | ip6_del_rt(rt); |
| 952 | } |
| 953 | |
| 954 | out: |
| 955 | neigh_release(neigh); |
| 956 | } |
| 957 | } |
| 958 | |
| 959 | static void ndisc_recv_rs(struct sk_buff *skb) |
| 960 | { |
| 961 | struct rs_msg *rs_msg = (struct rs_msg *)skb_transport_header(skb); |
| 962 | unsigned long ndoptlen = skb->len - sizeof(*rs_msg); |
| 963 | struct neighbour *neigh; |
| 964 | struct inet6_dev *idev; |
| 965 | const struct in6_addr *saddr = &ipv6_hdr(skb)->saddr; |
| 966 | struct ndisc_options ndopts; |
| 967 | u8 *lladdr = NULL; |
| 968 | |
| 969 | if (skb->len < sizeof(*rs_msg)) |
| 970 | return; |
| 971 | |
| 972 | idev = __in6_dev_get(skb->dev); |
| 973 | if (!idev) { |
| 974 | ND_PRINTK(1, err, "RS: can't find in6 device\n"); |
| 975 | return; |
| 976 | } |
| 977 | |
| 978 | /* Don't accept RS if we're not in router mode */ |
| 979 | if (!idev->cnf.forwarding) |
| 980 | goto out; |
| 981 | |
| 982 | /* |
| 983 | * Don't update NCE if src = ::; |
| 984 | * this implies that the source node has no ip address assigned yet. |
| 985 | */ |
| 986 | if (ipv6_addr_any(saddr)) |
| 987 | goto out; |
| 988 | |
| 989 | /* Parse ND options */ |
| 990 | if (!ndisc_parse_options(rs_msg->opt, ndoptlen, &ndopts)) { |
| 991 | ND_PRINTK(2, notice, "NS: invalid ND option, ignored\n"); |
| 992 | goto out; |
| 993 | } |
| 994 | |
| 995 | if (ndopts.nd_opts_src_lladdr) { |
| 996 | lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr, |
| 997 | skb->dev); |
| 998 | if (!lladdr) |
| 999 | goto out; |
| 1000 | } |
| 1001 | |
| 1002 | neigh = __neigh_lookup(&nd_tbl, saddr, skb->dev, 1); |
| 1003 | if (neigh) { |
| 1004 | neigh_update(neigh, lladdr, NUD_STALE, |
| 1005 | NEIGH_UPDATE_F_WEAK_OVERRIDE| |
| 1006 | NEIGH_UPDATE_F_OVERRIDE| |
| 1007 | NEIGH_UPDATE_F_OVERRIDE_ISROUTER); |
| 1008 | neigh_release(neigh); |
| 1009 | } |
| 1010 | out: |
| 1011 | return; |
| 1012 | } |
| 1013 | |
| 1014 | static void ndisc_ra_useropt(struct sk_buff *ra, struct nd_opt_hdr *opt) |
| 1015 | { |
| 1016 | struct icmp6hdr *icmp6h = (struct icmp6hdr *)skb_transport_header(ra); |
| 1017 | struct sk_buff *skb; |
| 1018 | struct nlmsghdr *nlh; |
| 1019 | struct nduseroptmsg *ndmsg; |
| 1020 | struct net *net = dev_net(ra->dev); |
| 1021 | int err; |
| 1022 | int base_size = NLMSG_ALIGN(sizeof(struct nduseroptmsg) |
| 1023 | + (opt->nd_opt_len << 3)); |
| 1024 | size_t msg_size = base_size + nla_total_size(sizeof(struct in6_addr)); |
| 1025 | |
| 1026 | skb = nlmsg_new(msg_size, GFP_ATOMIC); |
| 1027 | if (skb == NULL) { |
| 1028 | err = -ENOBUFS; |
| 1029 | goto errout; |
| 1030 | } |
| 1031 | |
| 1032 | nlh = nlmsg_put(skb, 0, 0, RTM_NEWNDUSEROPT, base_size, 0); |
| 1033 | if (nlh == NULL) { |
| 1034 | goto nla_put_failure; |
| 1035 | } |
| 1036 | |
| 1037 | ndmsg = nlmsg_data(nlh); |
| 1038 | ndmsg->nduseropt_family = AF_INET6; |
| 1039 | ndmsg->nduseropt_ifindex = ra->dev->ifindex; |
| 1040 | ndmsg->nduseropt_icmp_type = icmp6h->icmp6_type; |
| 1041 | ndmsg->nduseropt_icmp_code = icmp6h->icmp6_code; |
| 1042 | ndmsg->nduseropt_opts_len = opt->nd_opt_len << 3; |
| 1043 | |
| 1044 | memcpy(ndmsg + 1, opt, opt->nd_opt_len << 3); |
| 1045 | |
| 1046 | if (nla_put(skb, NDUSEROPT_SRCADDR, sizeof(struct in6_addr), |
| 1047 | &ipv6_hdr(ra)->saddr)) |
| 1048 | goto nla_put_failure; |
| 1049 | nlmsg_end(skb, nlh); |
| 1050 | |
| 1051 | rtnl_notify(skb, net, 0, RTNLGRP_ND_USEROPT, NULL, GFP_ATOMIC); |
| 1052 | return; |
| 1053 | |
| 1054 | nla_put_failure: |
| 1055 | nlmsg_free(skb); |
| 1056 | err = -EMSGSIZE; |
| 1057 | errout: |
| 1058 | rtnl_set_sk_err(net, RTNLGRP_ND_USEROPT, err); |
| 1059 | } |
| 1060 | |
| 1061 | static void ndisc_router_discovery(struct sk_buff *skb) |
| 1062 | { |
| 1063 | struct ra_msg *ra_msg = (struct ra_msg *)skb_transport_header(skb); |
| 1064 | struct neighbour *neigh = NULL; |
| 1065 | struct inet6_dev *in6_dev; |
| 1066 | struct rt6_info *rt = NULL; |
| 1067 | int lifetime; |
| 1068 | struct ndisc_options ndopts; |
| 1069 | int optlen; |
| 1070 | unsigned int pref = 0; |
| 1071 | |
| 1072 | __u8 * opt = (__u8 *)(ra_msg + 1); |
| 1073 | |
| 1074 | optlen = (skb->tail - skb->transport_header) - sizeof(struct ra_msg); |
| 1075 | |
| 1076 | if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) { |
| 1077 | ND_PRINTK(2, warn, "RA: source address is not link-local\n"); |
| 1078 | return; |
| 1079 | } |
| 1080 | if (optlen < 0) { |
| 1081 | ND_PRINTK(2, warn, "RA: packet too short\n"); |
| 1082 | return; |
| 1083 | } |
| 1084 | |
| 1085 | #ifdef CONFIG_IPV6_NDISC_NODETYPE |
| 1086 | if (skb->ndisc_nodetype == NDISC_NODETYPE_HOST) { |
| 1087 | ND_PRINTK(2, warn, "RA: from host or unauthorized router\n"); |
| 1088 | return; |
| 1089 | } |
| 1090 | #endif |
| 1091 | |
| 1092 | /* |
| 1093 | * set the RA_RECV flag in the interface |
| 1094 | */ |
| 1095 | |
| 1096 | in6_dev = __in6_dev_get(skb->dev); |
| 1097 | if (in6_dev == NULL) { |
| 1098 | ND_PRINTK(0, err, "RA: can't find inet6 device for %s\n", |
| 1099 | skb->dev->name); |
| 1100 | return; |
| 1101 | } |
| 1102 | |
| 1103 | if (!ndisc_parse_options(opt, optlen, &ndopts)) { |
| 1104 | ND_PRINTK(2, warn, "RA: invalid ND options\n"); |
| 1105 | return; |
| 1106 | } |
| 1107 | |
| 1108 | if (!ipv6_accept_ra(in6_dev)) |
| 1109 | goto skip_linkparms; |
| 1110 | |
| 1111 | #ifdef CONFIG_IPV6_NDISC_NODETYPE |
| 1112 | /* skip link-specific parameters from interior routers */ |
| 1113 | if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT) |
| 1114 | goto skip_linkparms; |
| 1115 | #endif |
| 1116 | |
| 1117 | if (in6_dev->if_flags & IF_RS_SENT) { |
| 1118 | /* |
| 1119 | * flag that an RA was received after an RS was sent |
| 1120 | * out on this interface. |
| 1121 | */ |
| 1122 | in6_dev->if_flags |= IF_RA_RCVD; |
| 1123 | } |
| 1124 | |
| 1125 | /* |
| 1126 | * Remember the managed/otherconf flags from most recently |
| 1127 | * received RA message (RFC 2462) -- yoshfuji |
| 1128 | */ |
| 1129 | in6_dev->if_flags = (in6_dev->if_flags & ~(IF_RA_MANAGED | |
| 1130 | IF_RA_OTHERCONF)) | |
| 1131 | (ra_msg->icmph.icmp6_addrconf_managed ? |
| 1132 | IF_RA_MANAGED : 0) | |
| 1133 | (ra_msg->icmph.icmp6_addrconf_other ? |
| 1134 | IF_RA_OTHERCONF : 0); |
| 1135 | |
| 1136 | if (!in6_dev->cnf.accept_ra_defrtr) |
| 1137 | goto skip_defrtr; |
| 1138 | |
| 1139 | if (ipv6_chk_addr(dev_net(in6_dev->dev), &ipv6_hdr(skb)->saddr, NULL, 0)) |
| 1140 | goto skip_defrtr; |
| 1141 | |
| 1142 | lifetime = ntohs(ra_msg->icmph.icmp6_rt_lifetime); |
| 1143 | |
| 1144 | #ifdef CONFIG_IPV6_ROUTER_PREF |
| 1145 | pref = ra_msg->icmph.icmp6_router_pref; |
| 1146 | /* 10b is handled as if it were 00b (medium) */ |
| 1147 | if (pref == ICMPV6_ROUTER_PREF_INVALID || |
| 1148 | !in6_dev->cnf.accept_ra_rtr_pref) |
| 1149 | pref = ICMPV6_ROUTER_PREF_MEDIUM; |
| 1150 | #endif |
| 1151 | |
| 1152 | rt = rt6_get_dflt_router(&ipv6_hdr(skb)->saddr, skb->dev); |
| 1153 | |
| 1154 | if (rt) { |
| 1155 | neigh = dst_neigh_lookup(&rt->dst, &ipv6_hdr(skb)->saddr); |
| 1156 | if (!neigh) { |
| 1157 | ND_PRINTK(0, err, |
| 1158 | "RA: %s got default router without neighbour\n", |
| 1159 | __func__); |
| 1160 | ip6_rt_put(rt); |
| 1161 | return; |
| 1162 | } |
| 1163 | } |
| 1164 | if (rt && lifetime == 0) { |
| 1165 | ip6_del_rt(rt); |
| 1166 | rt = NULL; |
| 1167 | } |
| 1168 | |
| 1169 | if (rt == NULL && lifetime) { |
| 1170 | ND_PRINTK(3, dbg, "RA: adding default router\n"); |
| 1171 | |
| 1172 | rt = rt6_add_dflt_router(&ipv6_hdr(skb)->saddr, skb->dev, pref); |
| 1173 | if (rt == NULL) { |
| 1174 | ND_PRINTK(0, err, |
| 1175 | "RA: %s failed to add default route\n", |
| 1176 | __func__); |
| 1177 | return; |
| 1178 | } |
| 1179 | |
| 1180 | neigh = dst_neigh_lookup(&rt->dst, &ipv6_hdr(skb)->saddr); |
| 1181 | if (neigh == NULL) { |
| 1182 | ND_PRINTK(0, err, |
| 1183 | "RA: %s got default router without neighbour\n", |
| 1184 | __func__); |
| 1185 | ip6_rt_put(rt); |
| 1186 | return; |
| 1187 | } |
| 1188 | neigh->flags |= NTF_ROUTER; |
| 1189 | } else if (rt) { |
| 1190 | rt->rt6i_flags = (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref); |
| 1191 | } |
| 1192 | |
| 1193 | if (rt) |
| 1194 | rt6_set_expires(rt, jiffies + (HZ * lifetime)); |
| 1195 | if (ra_msg->icmph.icmp6_hop_limit) { |
| 1196 | /* Only set hop_limit on the interface if it is higher than |
| 1197 | * the current hop_limit. |
| 1198 | */ |
| 1199 | if (in6_dev->cnf.hop_limit < ra_msg->icmph.icmp6_hop_limit) { |
| 1200 | in6_dev->cnf.hop_limit = ra_msg->icmph.icmp6_hop_limit; |
| 1201 | } else { |
| 1202 | ND_PRINTK(2, warn, "RA: Got route advertisement with lower hop_limit than current\n"); |
| 1203 | } |
| 1204 | if (rt) |
| 1205 | dst_metric_set(&rt->dst, RTAX_HOPLIMIT, |
| 1206 | ra_msg->icmph.icmp6_hop_limit); |
| 1207 | } |
| 1208 | |
| 1209 | skip_defrtr: |
| 1210 | |
| 1211 | /* |
| 1212 | * Update Reachable Time and Retrans Timer |
| 1213 | */ |
| 1214 | |
| 1215 | if (in6_dev->nd_parms) { |
| 1216 | unsigned long rtime = ntohl(ra_msg->retrans_timer); |
| 1217 | |
| 1218 | if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/HZ) { |
| 1219 | rtime = (rtime*HZ)/1000; |
| 1220 | if (rtime < HZ/10) |
| 1221 | rtime = HZ/10; |
| 1222 | in6_dev->nd_parms->retrans_time = rtime; |
| 1223 | in6_dev->tstamp = jiffies; |
| 1224 | inet6_ifinfo_notify(RTM_NEWLINK, in6_dev); |
| 1225 | } |
| 1226 | |
| 1227 | rtime = ntohl(ra_msg->reachable_time); |
| 1228 | if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/(3*HZ)) { |
| 1229 | rtime = (rtime*HZ)/1000; |
| 1230 | |
| 1231 | if (rtime < HZ/10) |
| 1232 | rtime = HZ/10; |
| 1233 | |
| 1234 | if (rtime != in6_dev->nd_parms->base_reachable_time) { |
| 1235 | in6_dev->nd_parms->base_reachable_time = rtime; |
| 1236 | in6_dev->nd_parms->gc_staletime = 3 * rtime; |
| 1237 | in6_dev->nd_parms->reachable_time = neigh_rand_reach_time(rtime); |
| 1238 | in6_dev->tstamp = jiffies; |
| 1239 | inet6_ifinfo_notify(RTM_NEWLINK, in6_dev); |
| 1240 | } |
| 1241 | } |
| 1242 | } |
| 1243 | |
| 1244 | skip_linkparms: |
| 1245 | |
| 1246 | /* |
| 1247 | * Process options. |
| 1248 | */ |
| 1249 | |
| 1250 | if (!neigh) |
| 1251 | neigh = __neigh_lookup(&nd_tbl, &ipv6_hdr(skb)->saddr, |
| 1252 | skb->dev, 1); |
| 1253 | if (neigh) { |
| 1254 | u8 *lladdr = NULL; |
| 1255 | if (ndopts.nd_opts_src_lladdr) { |
| 1256 | lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr, |
| 1257 | skb->dev); |
| 1258 | if (!lladdr) { |
| 1259 | ND_PRINTK(2, warn, |
| 1260 | "RA: invalid link-layer address length\n"); |
| 1261 | goto out; |
| 1262 | } |
| 1263 | } |
| 1264 | neigh_update(neigh, lladdr, NUD_STALE, |
| 1265 | NEIGH_UPDATE_F_WEAK_OVERRIDE| |
| 1266 | NEIGH_UPDATE_F_OVERRIDE| |
| 1267 | NEIGH_UPDATE_F_OVERRIDE_ISROUTER| |
| 1268 | NEIGH_UPDATE_F_ISROUTER); |
| 1269 | } |
| 1270 | |
| 1271 | if (!ipv6_accept_ra(in6_dev)) |
| 1272 | goto out; |
| 1273 | |
| 1274 | #ifdef CONFIG_IPV6_ROUTE_INFO |
| 1275 | if (ipv6_chk_addr(dev_net(in6_dev->dev), &ipv6_hdr(skb)->saddr, NULL, 0)) |
| 1276 | goto skip_routeinfo; |
| 1277 | |
| 1278 | if (in6_dev->cnf.accept_ra_rtr_pref && ndopts.nd_opts_ri) { |
| 1279 | struct nd_opt_hdr *p; |
| 1280 | for (p = ndopts.nd_opts_ri; |
| 1281 | p; |
| 1282 | p = ndisc_next_option(p, ndopts.nd_opts_ri_end)) { |
| 1283 | struct route_info *ri = (struct route_info *)p; |
| 1284 | #ifdef CONFIG_IPV6_NDISC_NODETYPE |
| 1285 | if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT && |
| 1286 | ri->prefix_len == 0) |
| 1287 | continue; |
| 1288 | #endif |
| 1289 | if (ri->prefix_len > in6_dev->cnf.accept_ra_rt_info_max_plen) |
| 1290 | continue; |
| 1291 | rt6_route_rcv(skb->dev, (u8*)p, (p->nd_opt_len) << 3, |
| 1292 | &ipv6_hdr(skb)->saddr); |
| 1293 | } |
| 1294 | } |
| 1295 | |
| 1296 | skip_routeinfo: |
| 1297 | #endif |
| 1298 | |
| 1299 | #ifdef CONFIG_IPV6_NDISC_NODETYPE |
| 1300 | /* skip link-specific ndopts from interior routers */ |
| 1301 | if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT) |
| 1302 | goto out; |
| 1303 | #endif |
| 1304 | |
| 1305 | if (in6_dev->cnf.accept_ra_pinfo && ndopts.nd_opts_pi) { |
| 1306 | struct nd_opt_hdr *p; |
| 1307 | for (p = ndopts.nd_opts_pi; |
| 1308 | p; |
| 1309 | p = ndisc_next_option(p, ndopts.nd_opts_pi_end)) { |
| 1310 | addrconf_prefix_rcv(skb->dev, (u8 *)p, |
| 1311 | (p->nd_opt_len) << 3, |
| 1312 | ndopts.nd_opts_src_lladdr != NULL); |
| 1313 | } |
| 1314 | } |
| 1315 | |
| 1316 | if (ndopts.nd_opts_mtu) { |
| 1317 | __be32 n; |
| 1318 | u32 mtu; |
| 1319 | |
| 1320 | memcpy(&n, ((u8*)(ndopts.nd_opts_mtu+1))+2, sizeof(mtu)); |
| 1321 | mtu = ntohl(n); |
| 1322 | |
| 1323 | if (mtu < IPV6_MIN_MTU || mtu > skb->dev->mtu) { |
| 1324 | ND_PRINTK(2, warn, "RA: invalid mtu: %d\n", mtu); |
| 1325 | } else if (in6_dev->cnf.mtu6 != mtu) { |
| 1326 | in6_dev->cnf.mtu6 = mtu; |
| 1327 | |
| 1328 | if (rt) |
| 1329 | dst_metric_set(&rt->dst, RTAX_MTU, mtu); |
| 1330 | |
| 1331 | rt6_mtu_change(skb->dev, mtu); |
| 1332 | } |
| 1333 | } |
| 1334 | |
| 1335 | #ifdef CONFIG_MTK_DHCPV6C_WIFI |
| 1336 | if (in6_dev->if_flags & IF_RA_OTHERCONF){ |
| 1337 | printk(KERN_INFO "[mtk_net][ipv6]receive RA with o bit!\n"); |
| 1338 | in6_dev->cnf.ra_info_flag = 1; |
| 1339 | } |
| 1340 | if(in6_dev->if_flags & IF_RA_MANAGED){ |
| 1341 | printk(KERN_INFO "[mtk_net][ipv6]receive RA with m bit!\n"); |
| 1342 | in6_dev->cnf.ra_info_flag = 2; |
| 1343 | } |
| 1344 | if(in6_dev->cnf.ra_info_flag == 0){ |
| 1345 | printk(KERN_INFO "[mtk_net][ipv6]receive RA neither O nor M bit is set!\n"); |
| 1346 | in6_dev->cnf.ra_info_flag = 4; |
| 1347 | } |
| 1348 | #endif |
| 1349 | |
| 1350 | if (ndopts.nd_useropts) { |
| 1351 | struct nd_opt_hdr *p; |
| 1352 | for (p = ndopts.nd_useropts; |
| 1353 | p; |
| 1354 | p = ndisc_next_useropt(p, ndopts.nd_useropts_end)) { |
| 1355 | ndisc_ra_useropt(skb, p); |
| 1356 | #ifdef CONFIG_MTK_DHCPV6C_WIFI |
| 1357 | /* only clear ra_info_flag when O bit is set */ |
| 1358 | if (p->nd_opt_type == ND_OPT_RDNSS && |
| 1359 | in6_dev->if_flags & IF_RA_OTHERCONF) { |
| 1360 | printk(KERN_INFO "[mtk_net][ipv6]RDNSS, ignore RA with o bit!\n"); |
| 1361 | in6_dev->cnf.ra_info_flag = 0; |
| 1362 | } |
| 1363 | #endif |
| 1364 | } |
| 1365 | } |
| 1366 | |
| 1367 | if (ndopts.nd_opts_tgt_lladdr || ndopts.nd_opts_rh) { |
| 1368 | ND_PRINTK(2, warn, "RA: invalid RA options\n"); |
| 1369 | } |
| 1370 | out: |
| 1371 | ip6_rt_put(rt); |
| 1372 | if (neigh) |
| 1373 | neigh_release(neigh); |
| 1374 | } |
| 1375 | |
| 1376 | static void ndisc_redirect_rcv(struct sk_buff *skb) |
| 1377 | { |
| 1378 | u8 *hdr; |
| 1379 | struct ndisc_options ndopts; |
| 1380 | struct rd_msg *msg = (struct rd_msg *)skb_transport_header(skb); |
| 1381 | u32 ndoptlen = skb->tail - (skb->transport_header + |
| 1382 | offsetof(struct rd_msg, opt)); |
| 1383 | |
| 1384 | #ifdef CONFIG_IPV6_NDISC_NODETYPE |
| 1385 | switch (skb->ndisc_nodetype) { |
| 1386 | case NDISC_NODETYPE_HOST: |
| 1387 | case NDISC_NODETYPE_NODEFAULT: |
| 1388 | ND_PRINTK(2, warn, |
| 1389 | "Redirect: from host or unauthorized router\n"); |
| 1390 | return; |
| 1391 | } |
| 1392 | #endif |
| 1393 | |
| 1394 | if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) { |
| 1395 | ND_PRINTK(2, warn, |
| 1396 | "Redirect: source address is not link-local\n"); |
| 1397 | return; |
| 1398 | } |
| 1399 | |
| 1400 | if (!ndisc_parse_options(msg->opt, ndoptlen, &ndopts)) |
| 1401 | return; |
| 1402 | |
| 1403 | if (!ndopts.nd_opts_rh) |
| 1404 | return; |
| 1405 | |
| 1406 | hdr = (u8 *)ndopts.nd_opts_rh; |
| 1407 | hdr += 8; |
| 1408 | if (!pskb_pull(skb, hdr - skb_transport_header(skb))) |
| 1409 | return; |
| 1410 | |
| 1411 | icmpv6_notify(skb, NDISC_REDIRECT, 0, 0); |
| 1412 | } |
| 1413 | |
| 1414 | static void ndisc_fill_redirect_hdr_option(struct sk_buff *skb, |
| 1415 | struct sk_buff *orig_skb, |
| 1416 | int rd_len) |
| 1417 | { |
| 1418 | u8 *opt = skb_put(skb, rd_len); |
| 1419 | |
| 1420 | memset(opt, 0, 8); |
| 1421 | *(opt++) = ND_OPT_REDIRECT_HDR; |
| 1422 | *(opt++) = (rd_len >> 3); |
| 1423 | opt += 6; |
| 1424 | |
| 1425 | memcpy(opt, ipv6_hdr(orig_skb), rd_len - 8); |
| 1426 | } |
| 1427 | |
| 1428 | void ndisc_send_redirect(struct sk_buff *skb, const struct in6_addr *target) |
| 1429 | { |
| 1430 | struct net_device *dev = skb->dev; |
| 1431 | struct net *net = dev_net(dev); |
| 1432 | struct sock *sk = net->ipv6.ndisc_sk; |
| 1433 | int optlen = 0; |
| 1434 | struct inet_peer *peer; |
| 1435 | struct sk_buff *buff; |
| 1436 | struct rd_msg *msg; |
| 1437 | struct in6_addr saddr_buf; |
| 1438 | struct rt6_info *rt; |
| 1439 | struct dst_entry *dst; |
| 1440 | struct flowi6 fl6; |
| 1441 | int rd_len; |
| 1442 | u8 ha_buf[MAX_ADDR_LEN], *ha = NULL; |
| 1443 | bool ret; |
| 1444 | |
| 1445 | if (ipv6_get_lladdr(dev, &saddr_buf, IFA_F_TENTATIVE)) { |
| 1446 | ND_PRINTK(2, warn, "Redirect: no link-local address on %s\n", |
| 1447 | dev->name); |
| 1448 | return; |
| 1449 | } |
| 1450 | |
| 1451 | if (!ipv6_addr_equal(&ipv6_hdr(skb)->daddr, target) && |
| 1452 | ipv6_addr_type(target) != (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) { |
| 1453 | ND_PRINTK(2, warn, |
| 1454 | "Redirect: target address is not link-local unicast\n"); |
| 1455 | return; |
| 1456 | } |
| 1457 | |
| 1458 | icmpv6_flow_init(sk, &fl6, NDISC_REDIRECT, |
| 1459 | &saddr_buf, &ipv6_hdr(skb)->saddr, dev->ifindex); |
| 1460 | |
| 1461 | dst = ip6_route_output(net, NULL, &fl6); |
| 1462 | if (dst->error) { |
| 1463 | dst_release(dst); |
| 1464 | return; |
| 1465 | } |
| 1466 | dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), NULL, 0); |
| 1467 | if (IS_ERR(dst)) |
| 1468 | return; |
| 1469 | |
| 1470 | rt = (struct rt6_info *) dst; |
| 1471 | |
| 1472 | if (rt->rt6i_flags & RTF_GATEWAY) { |
| 1473 | ND_PRINTK(2, warn, |
| 1474 | "Redirect: destination is not a neighbour\n"); |
| 1475 | goto release; |
| 1476 | } |
| 1477 | peer = inet_getpeer_v6(net->ipv6.peers, &rt->rt6i_dst.addr, 1); |
| 1478 | ret = inet_peer_xrlim_allow(peer, 1*HZ); |
| 1479 | if (peer) |
| 1480 | inet_putpeer(peer); |
| 1481 | if (!ret) |
| 1482 | goto release; |
| 1483 | |
| 1484 | if (dev->addr_len) { |
| 1485 | struct neighbour *neigh = dst_neigh_lookup(skb_dst(skb), target); |
| 1486 | if (!neigh) { |
| 1487 | ND_PRINTK(2, warn, |
| 1488 | "Redirect: no neigh for target address\n"); |
| 1489 | goto release; |
| 1490 | } |
| 1491 | |
| 1492 | read_lock_bh(&neigh->lock); |
| 1493 | if (neigh->nud_state & NUD_VALID) { |
| 1494 | memcpy(ha_buf, neigh->ha, dev->addr_len); |
| 1495 | read_unlock_bh(&neigh->lock); |
| 1496 | ha = ha_buf; |
| 1497 | optlen += ndisc_opt_addr_space(dev); |
| 1498 | } else |
| 1499 | read_unlock_bh(&neigh->lock); |
| 1500 | |
| 1501 | neigh_release(neigh); |
| 1502 | } |
| 1503 | |
| 1504 | rd_len = min_t(unsigned int, |
| 1505 | IPV6_MIN_MTU - sizeof(struct ipv6hdr) - sizeof(*msg) - optlen, |
| 1506 | skb->len + 8); |
| 1507 | rd_len &= ~0x7; |
| 1508 | optlen += rd_len; |
| 1509 | |
| 1510 | buff = ndisc_alloc_skb(dev, sizeof(*msg) + optlen); |
| 1511 | if (!buff) |
| 1512 | goto release; |
| 1513 | |
| 1514 | msg = (struct rd_msg *)skb_put(buff, sizeof(*msg)); |
| 1515 | *msg = (struct rd_msg) { |
| 1516 | .icmph = { |
| 1517 | .icmp6_type = NDISC_REDIRECT, |
| 1518 | }, |
| 1519 | .target = *target, |
| 1520 | .dest = ipv6_hdr(skb)->daddr, |
| 1521 | }; |
| 1522 | |
| 1523 | /* |
| 1524 | * include target_address option |
| 1525 | */ |
| 1526 | |
| 1527 | if (ha) |
| 1528 | ndisc_fill_addr_option(buff, ND_OPT_TARGET_LL_ADDR, ha); |
| 1529 | |
| 1530 | /* |
| 1531 | * build redirect option and copy skb over to the new packet. |
| 1532 | */ |
| 1533 | |
| 1534 | if (rd_len) |
| 1535 | ndisc_fill_redirect_hdr_option(buff, skb, rd_len); |
| 1536 | |
| 1537 | skb_dst_set(buff, dst); |
| 1538 | ndisc_send_skb(buff, &ipv6_hdr(skb)->saddr, &saddr_buf); |
| 1539 | return; |
| 1540 | |
| 1541 | release: |
| 1542 | dst_release(dst); |
| 1543 | } |
| 1544 | |
| 1545 | static void pndisc_redo(struct sk_buff *skb) |
| 1546 | { |
| 1547 | ndisc_recv_ns(skb); |
| 1548 | kfree_skb(skb); |
| 1549 | } |
| 1550 | |
| 1551 | int ndisc_rcv(struct sk_buff *skb) |
| 1552 | { |
| 1553 | struct nd_msg *msg; |
| 1554 | |
| 1555 | if (skb_linearize(skb)) |
| 1556 | return 0; |
| 1557 | |
| 1558 | msg = (struct nd_msg *)skb_transport_header(skb); |
| 1559 | |
| 1560 | __skb_push(skb, skb->data - skb_transport_header(skb)); |
| 1561 | |
| 1562 | if (ipv6_hdr(skb)->hop_limit != 255) { |
| 1563 | ND_PRINTK(2, warn, "NDISC: invalid hop-limit: %d\n", |
| 1564 | ipv6_hdr(skb)->hop_limit); |
| 1565 | return 0; |
| 1566 | } |
| 1567 | |
| 1568 | if (msg->icmph.icmp6_code != 0) { |
| 1569 | ND_PRINTK(2, warn, "NDISC: invalid ICMPv6 code: %d\n", |
| 1570 | msg->icmph.icmp6_code); |
| 1571 | return 0; |
| 1572 | } |
| 1573 | |
| 1574 | memset(NEIGH_CB(skb), 0, sizeof(struct neighbour_cb)); |
| 1575 | |
| 1576 | switch (msg->icmph.icmp6_type) { |
| 1577 | case NDISC_NEIGHBOUR_SOLICITATION: |
| 1578 | ndisc_recv_ns(skb); |
| 1579 | break; |
| 1580 | |
| 1581 | case NDISC_NEIGHBOUR_ADVERTISEMENT: |
| 1582 | ndisc_recv_na(skb); |
| 1583 | break; |
| 1584 | |
| 1585 | case NDISC_ROUTER_SOLICITATION: |
| 1586 | ndisc_recv_rs(skb); |
| 1587 | break; |
| 1588 | |
| 1589 | case NDISC_ROUTER_ADVERTISEMENT: |
| 1590 | ndisc_router_discovery(skb); |
| 1591 | break; |
| 1592 | |
| 1593 | case NDISC_REDIRECT: |
| 1594 | ndisc_redirect_rcv(skb); |
| 1595 | break; |
| 1596 | } |
| 1597 | |
| 1598 | return 0; |
| 1599 | } |
| 1600 | |
| 1601 | static int ndisc_netdev_event(struct notifier_block *this, unsigned long event, void *ptr) |
| 1602 | { |
| 1603 | struct net_device *dev = ptr; |
| 1604 | struct net *net = dev_net(dev); |
| 1605 | struct inet6_dev *idev; |
| 1606 | |
| 1607 | switch (event) { |
| 1608 | case NETDEV_CHANGEADDR: |
| 1609 | neigh_changeaddr(&nd_tbl, dev); |
| 1610 | fib6_run_gc(0, net, false); |
| 1611 | idev = in6_dev_get(dev); |
| 1612 | if (!idev) |
| 1613 | break; |
| 1614 | if (idev->cnf.ndisc_notify) |
| 1615 | ndisc_send_unsol_na(dev); |
| 1616 | in6_dev_put(idev); |
| 1617 | break; |
| 1618 | case NETDEV_DOWN: |
| 1619 | neigh_ifdown(&nd_tbl, dev); |
| 1620 | fib6_run_gc(0, net, false); |
| 1621 | break; |
| 1622 | case NETDEV_NOTIFY_PEERS: |
| 1623 | ndisc_send_unsol_na(dev); |
| 1624 | break; |
| 1625 | default: |
| 1626 | break; |
| 1627 | } |
| 1628 | |
| 1629 | return NOTIFY_DONE; |
| 1630 | } |
| 1631 | |
| 1632 | static struct notifier_block ndisc_netdev_notifier = { |
| 1633 | .notifier_call = ndisc_netdev_event, |
| 1634 | }; |
| 1635 | |
| 1636 | #ifdef CONFIG_SYSCTL |
| 1637 | static void ndisc_warn_deprecated_sysctl(struct ctl_table *ctl, |
| 1638 | const char *func, const char *dev_name) |
| 1639 | { |
| 1640 | static char warncomm[TASK_COMM_LEN]; |
| 1641 | static int warned; |
| 1642 | if (strcmp(warncomm, current->comm) && warned < 5) { |
| 1643 | strcpy(warncomm, current->comm); |
| 1644 | pr_warn("process `%s' is using deprecated sysctl (%s) net.ipv6.neigh.%s.%s - use net.ipv6.neigh.%s.%s_ms instead\n", |
| 1645 | warncomm, func, |
| 1646 | dev_name, ctl->procname, |
| 1647 | dev_name, ctl->procname); |
| 1648 | warned++; |
| 1649 | } |
| 1650 | } |
| 1651 | |
| 1652 | int ndisc_ifinfo_sysctl_change(struct ctl_table *ctl, int write, void __user *buffer, size_t *lenp, loff_t *ppos) |
| 1653 | { |
| 1654 | struct net_device *dev = ctl->extra1; |
| 1655 | struct inet6_dev *idev; |
| 1656 | int ret; |
| 1657 | |
| 1658 | if ((strcmp(ctl->procname, "retrans_time") == 0) || |
| 1659 | (strcmp(ctl->procname, "base_reachable_time") == 0)) |
| 1660 | ndisc_warn_deprecated_sysctl(ctl, "syscall", dev ? dev->name : "default"); |
| 1661 | |
| 1662 | if (strcmp(ctl->procname, "retrans_time") == 0) |
| 1663 | ret = proc_dointvec(ctl, write, buffer, lenp, ppos); |
| 1664 | |
| 1665 | else if (strcmp(ctl->procname, "base_reachable_time") == 0) |
| 1666 | ret = proc_dointvec_jiffies(ctl, write, |
| 1667 | buffer, lenp, ppos); |
| 1668 | |
| 1669 | else if ((strcmp(ctl->procname, "retrans_time_ms") == 0) || |
| 1670 | (strcmp(ctl->procname, "base_reachable_time_ms") == 0)) |
| 1671 | ret = proc_dointvec_ms_jiffies(ctl, write, |
| 1672 | buffer, lenp, ppos); |
| 1673 | else |
| 1674 | ret = -1; |
| 1675 | |
| 1676 | if (write && ret == 0 && dev && (idev = in6_dev_get(dev)) != NULL) { |
| 1677 | if (ctl->data == &idev->nd_parms->base_reachable_time) |
| 1678 | idev->nd_parms->reachable_time = neigh_rand_reach_time(idev->nd_parms->base_reachable_time); |
| 1679 | idev->tstamp = jiffies; |
| 1680 | inet6_ifinfo_notify(RTM_NEWLINK, idev); |
| 1681 | in6_dev_put(idev); |
| 1682 | } |
| 1683 | return ret; |
| 1684 | } |
| 1685 | |
| 1686 | |
| 1687 | #endif |
| 1688 | |
| 1689 | static int __net_init ndisc_net_init(struct net *net) |
| 1690 | { |
| 1691 | struct ipv6_pinfo *np; |
| 1692 | struct sock *sk; |
| 1693 | int err; |
| 1694 | |
| 1695 | err = inet_ctl_sock_create(&sk, PF_INET6, |
| 1696 | SOCK_RAW, IPPROTO_ICMPV6, net); |
| 1697 | if (err < 0) { |
| 1698 | ND_PRINTK(0, err, |
| 1699 | "NDISC: Failed to initialize the control socket (err %d)\n", |
| 1700 | err); |
| 1701 | return err; |
| 1702 | } |
| 1703 | |
| 1704 | net->ipv6.ndisc_sk = sk; |
| 1705 | |
| 1706 | np = inet6_sk(sk); |
| 1707 | np->hop_limit = 255; |
| 1708 | /* Do not loopback ndisc messages */ |
| 1709 | np->mc_loop = 0; |
| 1710 | |
| 1711 | return 0; |
| 1712 | } |
| 1713 | |
| 1714 | static void __net_exit ndisc_net_exit(struct net *net) |
| 1715 | { |
| 1716 | inet_ctl_sock_destroy(net->ipv6.ndisc_sk); |
| 1717 | } |
| 1718 | |
| 1719 | static struct pernet_operations ndisc_net_ops = { |
| 1720 | .init = ndisc_net_init, |
| 1721 | .exit = ndisc_net_exit, |
| 1722 | }; |
| 1723 | |
| 1724 | int __init ndisc_init(void) |
| 1725 | { |
| 1726 | int err; |
| 1727 | |
| 1728 | err = register_pernet_subsys(&ndisc_net_ops); |
| 1729 | if (err) |
| 1730 | return err; |
| 1731 | /* |
| 1732 | * Initialize the neighbour table |
| 1733 | */ |
| 1734 | neigh_table_init(&nd_tbl); |
| 1735 | |
| 1736 | #ifdef CONFIG_SYSCTL |
| 1737 | err = neigh_sysctl_register(NULL, &nd_tbl.parms, "ipv6", |
| 1738 | &ndisc_ifinfo_sysctl_change); |
| 1739 | if (err) |
| 1740 | goto out_unregister_pernet; |
| 1741 | #endif |
| 1742 | out: |
| 1743 | return err; |
| 1744 | |
| 1745 | #ifdef CONFIG_SYSCTL |
| 1746 | out_unregister_pernet: |
| 1747 | unregister_pernet_subsys(&ndisc_net_ops); |
| 1748 | goto out; |
| 1749 | #endif |
| 1750 | } |
| 1751 | |
| 1752 | int __init ndisc_late_init(void) |
| 1753 | { |
| 1754 | return register_netdevice_notifier(&ndisc_netdev_notifier); |
| 1755 | } |
| 1756 | |
| 1757 | void ndisc_late_cleanup(void) |
| 1758 | { |
| 1759 | unregister_netdevice_notifier(&ndisc_netdev_notifier); |
| 1760 | } |
| 1761 | |
| 1762 | void ndisc_cleanup(void) |
| 1763 | { |
| 1764 | #ifdef CONFIG_SYSCTL |
| 1765 | neigh_sysctl_unregister(&nd_tbl.parms); |
| 1766 | #endif |
| 1767 | neigh_table_clear(&nd_tbl); |
| 1768 | unregister_pernet_subsys(&ndisc_net_ops); |
| 1769 | } |