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 *	Pierre Ynard			:	export userland ND options
  19 *						through netlink (RDNSS support)
  20 *	Lars Fenneberg			:	fixed MTU setting on receipt
  21 *						of an RA.
  22 *	Janos Farkas			:	kmalloc failure checks
  23 *	Alexey Kuznetsov		:	state machine reworked
  24 *						and moved to net/core.
  25 *	Pekka Savola			:	RFC2461 validation
  26 *	YOSHIFUJI Hideaki @USAGI	:	Verify ND options properly
  27 */
  28
  29/* Set to 3 to get tracing... */
  30#define ND_DEBUG 1
  31
  32#define ND_PRINTK(fmt, args...) do { if (net_ratelimit()) { printk(fmt, ## args); } } while(0)
  33#define ND_NOPRINTK(x...) do { ; } while(0)
  34#define ND_PRINTK0 ND_PRINTK
  35#define ND_PRINTK1 ND_NOPRINTK
  36#define ND_PRINTK2 ND_NOPRINTK
  37#define ND_PRINTK3 ND_NOPRINTK
  38#if ND_DEBUG >= 1
  39#undef ND_PRINTK1
  40#define ND_PRINTK1 ND_PRINTK
  41#endif
  42#if ND_DEBUG >= 2
  43#undef ND_PRINTK2
  44#define ND_PRINTK2 ND_PRINTK
  45#endif
  46#if ND_DEBUG >= 3
  47#undef ND_PRINTK3
  48#define ND_PRINTK3 ND_PRINTK
  49#endif
  50
  51#include <linux/module.h>
  52#include <linux/errno.h>
  53#include <linux/types.h>
  54#include <linux/socket.h>
  55#include <linux/sockios.h>
  56#include <linux/sched.h>
  57#include <linux/net.h>
  58#include <linux/in6.h>
  59#include <linux/route.h>
  60#include <linux/init.h>
  61#include <linux/rcupdate.h>
  62#include <linux/slab.h>
  63#ifdef CONFIG_SYSCTL
  64#include <linux/sysctl.h>
  65#endif
  66
  67#include <linux/if_addr.h>
  68#include <linux/if_arp.h>
  69#include <linux/ipv6.h>
  70#include <linux/icmpv6.h>
  71#include <linux/jhash.h>
  72
  73#include <net/sock.h>
  74#include <net/snmp.h>
  75
  76#include <net/ipv6.h>
  77#include <net/protocol.h>
  78#include <net/ndisc.h>
  79#include <net/ip6_route.h>
  80#include <net/addrconf.h>
  81#include <net/icmp.h>
  82
  83#include <net/netlink.h>
  84#include <linux/rtnetlink.h>
  85
  86#include <net/flow.h>
  87#include <net/ip6_checksum.h>
  88#include <net/inet_common.h>
  89#include <linux/proc_fs.h>
  90
  91#include <linux/netfilter.h>
  92#include <linux/netfilter_ipv6.h>
  93
 
 
 
 
 
 
 
 
 
  94static u32 ndisc_hash(const void *pkey,
  95		      const struct net_device *dev,
  96		      __u32 rnd);
  97static int ndisc_constructor(struct neighbour *neigh);
  98static void ndisc_solicit(struct neighbour *neigh, struct sk_buff *skb);
  99static void ndisc_error_report(struct neighbour *neigh, struct sk_buff *skb);
 100static int pndisc_constructor(struct pneigh_entry *n);
 101static void pndisc_destructor(struct pneigh_entry *n);
 102static void pndisc_redo(struct sk_buff *skb);
 103
 104static const struct neigh_ops ndisc_generic_ops = {
 105	.family =		AF_INET6,
 106	.solicit =		ndisc_solicit,
 107	.error_report =		ndisc_error_report,
 108	.output =		neigh_resolve_output,
 109	.connected_output =	neigh_connected_output,
 110};
 111
 112static const struct neigh_ops ndisc_hh_ops = {
 113	.family =		AF_INET6,
 114	.solicit =		ndisc_solicit,
 115	.error_report =		ndisc_error_report,
 116	.output =		neigh_resolve_output,
 117	.connected_output =	neigh_resolve_output,
 118};
 119
 120
 121static const struct neigh_ops ndisc_direct_ops = {
 122	.family =		AF_INET6,
 123	.output =		neigh_direct_output,
 124	.connected_output =	neigh_direct_output,
 125};
 126
 127struct neigh_table nd_tbl = {
 128	.family =	AF_INET6,
 129	.entry_size =	sizeof(struct neighbour) + sizeof(struct in6_addr),
 130	.key_len =	sizeof(struct in6_addr),
 131	.hash =		ndisc_hash,
 132	.constructor =	ndisc_constructor,
 133	.pconstructor =	pndisc_constructor,
 134	.pdestructor =	pndisc_destructor,
 135	.proxy_redo =	pndisc_redo,
 136	.id =		"ndisc_cache",
 137	.parms = {
 138		.tbl			= &nd_tbl,
 139		.base_reachable_time	= ND_REACHABLE_TIME,
 140		.retrans_time		= ND_RETRANS_TIMER,
 141		.gc_staletime		= 60 * HZ,
 142		.reachable_time		= ND_REACHABLE_TIME,
 143		.delay_probe_time	= 5 * HZ,
 144		.queue_len		= 3,
 145		.ucast_probes		= 3,
 146		.mcast_probes		= 3,
 147		.anycast_delay		= 1 * HZ,
 148		.proxy_delay		= (8 * HZ) / 10,
 149		.proxy_qlen		= 64,
 150	},
 151	.gc_interval =	  30 * HZ,
 152	.gc_thresh1 =	 128,
 153	.gc_thresh2 =	 512,
 154	.gc_thresh3 =	1024,
 155};
 156
 157/* ND options */
 158struct ndisc_options {
 159	struct nd_opt_hdr *nd_opt_array[__ND_OPT_ARRAY_MAX];
 160#ifdef CONFIG_IPV6_ROUTE_INFO
 161	struct nd_opt_hdr *nd_opts_ri;
 162	struct nd_opt_hdr *nd_opts_ri_end;
 163#endif
 164	struct nd_opt_hdr *nd_useropts;
 165	struct nd_opt_hdr *nd_useropts_end;
 166};
 167
 168#define nd_opts_src_lladdr	nd_opt_array[ND_OPT_SOURCE_LL_ADDR]
 169#define nd_opts_tgt_lladdr	nd_opt_array[ND_OPT_TARGET_LL_ADDR]
 170#define nd_opts_pi		nd_opt_array[ND_OPT_PREFIX_INFO]
 171#define nd_opts_pi_end		nd_opt_array[__ND_OPT_PREFIX_INFO_END]
 172#define nd_opts_rh		nd_opt_array[ND_OPT_REDIRECT_HDR]
 173#define nd_opts_mtu		nd_opt_array[ND_OPT_MTU]
 174
 175#define NDISC_OPT_SPACE(len) (((len)+2+7)&~7)
 176
 177/*
 178 * Return the padding between the option length and the start of the
 179 * link addr.  Currently only IP-over-InfiniBand needs this, although
 180 * if RFC 3831 IPv6-over-Fibre Channel is ever implemented it may
 181 * also need a pad of 2.
 182 */
 183static int ndisc_addr_option_pad(unsigned short type)
 184{
 185	switch (type) {
 186	case ARPHRD_INFINIBAND: return 2;
 187	default:                return 0;
 188	}
 189}
 190
 191static inline int ndisc_opt_addr_space(struct net_device *dev)
 192{
 193	return NDISC_OPT_SPACE(dev->addr_len + ndisc_addr_option_pad(dev->type));
 194}
 195
 196static u8 *ndisc_fill_addr_option(u8 *opt, int type, void *data, int data_len,
 197				  unsigned short addr_type)
 198{
 199	int space = NDISC_OPT_SPACE(data_len);
 200	int pad   = ndisc_addr_option_pad(addr_type);
 201
 202	opt[0] = type;
 203	opt[1] = space>>3;
 204
 205	memset(opt + 2, 0, pad);
 206	opt   += pad;
 207	space -= pad;
 208
 209	memcpy(opt+2, data, data_len);
 210	data_len += 2;
 211	opt += data_len;
 212	if ((space -= data_len) > 0)
 213		memset(opt, 0, space);
 214	return opt + space;
 215}
 216
 217static struct nd_opt_hdr *ndisc_next_option(struct nd_opt_hdr *cur,
 218					    struct nd_opt_hdr *end)
 219{
 220	int type;
 221	if (!cur || !end || cur >= end)
 222		return NULL;
 223	type = cur->nd_opt_type;
 224	do {
 225		cur = ((void *)cur) + (cur->nd_opt_len << 3);
 226	} while(cur < end && cur->nd_opt_type != type);
 227	return cur <= end && cur->nd_opt_type == type ? cur : NULL;
 228}
 229
 230static inline int ndisc_is_useropt(struct nd_opt_hdr *opt)
 231{
 232	return opt->nd_opt_type == ND_OPT_RDNSS;
 
 233}
 234
 235static struct nd_opt_hdr *ndisc_next_useropt(struct nd_opt_hdr *cur,
 236					     struct nd_opt_hdr *end)
 237{
 238	if (!cur || !end || cur >= end)
 239		return NULL;
 240	do {
 241		cur = ((void *)cur) + (cur->nd_opt_len << 3);
 242	} while(cur < end && !ndisc_is_useropt(cur));
 243	return cur <= end && ndisc_is_useropt(cur) ? cur : NULL;
 244}
 245
 246static struct ndisc_options *ndisc_parse_options(u8 *opt, int opt_len,
 247						 struct ndisc_options *ndopts)
 248{
 249	struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)opt;
 250
 251	if (!nd_opt || opt_len < 0 || !ndopts)
 252		return NULL;
 253	memset(ndopts, 0, sizeof(*ndopts));
 254	while (opt_len) {
 255		int l;
 256		if (opt_len < sizeof(struct nd_opt_hdr))
 257			return NULL;
 258		l = nd_opt->nd_opt_len << 3;
 259		if (opt_len < l || l == 0)
 260			return NULL;
 261		switch (nd_opt->nd_opt_type) {
 262		case ND_OPT_SOURCE_LL_ADDR:
 263		case ND_OPT_TARGET_LL_ADDR:
 264		case ND_OPT_MTU:
 265		case ND_OPT_REDIRECT_HDR:
 266			if (ndopts->nd_opt_array[nd_opt->nd_opt_type]) {
 267				ND_PRINTK2(KERN_WARNING
 268					   "%s(): duplicated ND6 option found: type=%d\n",
 269					   __func__,
 270					   nd_opt->nd_opt_type);
 271			} else {
 272				ndopts->nd_opt_array[nd_opt->nd_opt_type] = nd_opt;
 273			}
 274			break;
 275		case ND_OPT_PREFIX_INFO:
 276			ndopts->nd_opts_pi_end = nd_opt;
 277			if (!ndopts->nd_opt_array[nd_opt->nd_opt_type])
 278				ndopts->nd_opt_array[nd_opt->nd_opt_type] = nd_opt;
 279			break;
 280#ifdef CONFIG_IPV6_ROUTE_INFO
 281		case ND_OPT_ROUTE_INFO:
 282			ndopts->nd_opts_ri_end = nd_opt;
 283			if (!ndopts->nd_opts_ri)
 284				ndopts->nd_opts_ri = nd_opt;
 285			break;
 286#endif
 287		default:
 288			if (ndisc_is_useropt(nd_opt)) {
 289				ndopts->nd_useropts_end = nd_opt;
 290				if (!ndopts->nd_useropts)
 291					ndopts->nd_useropts = nd_opt;
 292			} else {
 293				/*
 294				 * Unknown options must be silently ignored,
 295				 * to accommodate future extension to the
 296				 * protocol.
 297				 */
 298				ND_PRINTK2(KERN_NOTICE
 299					   "%s(): ignored unsupported option; type=%d, len=%d\n",
 300					   __func__,
 301					   nd_opt->nd_opt_type, nd_opt->nd_opt_len);
 
 302			}
 303		}
 304		opt_len -= l;
 305		nd_opt = ((void *)nd_opt) + l;
 306	}
 307	return ndopts;
 308}
 309
 310static inline u8 *ndisc_opt_addr_data(struct nd_opt_hdr *p,
 311				      struct net_device *dev)
 312{
 313	u8 *lladdr = (u8 *)(p + 1);
 314	int lladdrlen = p->nd_opt_len << 3;
 315	int prepad = ndisc_addr_option_pad(dev->type);
 316	if (lladdrlen != NDISC_OPT_SPACE(dev->addr_len + prepad))
 317		return NULL;
 318	return lladdr + prepad;
 319}
 320
 321int ndisc_mc_map(const struct in6_addr *addr, char *buf, struct net_device *dev, int dir)
 322{
 323	switch (dev->type) {
 324	case ARPHRD_ETHER:
 325	case ARPHRD_IEEE802:	/* Not sure. Check it later. --ANK */
 326	case ARPHRD_FDDI:
 327		ipv6_eth_mc_map(addr, buf);
 328		return 0;
 329	case ARPHRD_IEEE802_TR:
 330		ipv6_tr_mc_map(addr,buf);
 331		return 0;
 332	case ARPHRD_ARCNET:
 333		ipv6_arcnet_mc_map(addr, buf);
 334		return 0;
 335	case ARPHRD_INFINIBAND:
 336		ipv6_ib_mc_map(addr, dev->broadcast, buf);
 337		return 0;
 338	case ARPHRD_IPGRE:
 339		return ipv6_ipgre_mc_map(addr, dev->broadcast, buf);
 340	default:
 341		if (dir) {
 342			memcpy(buf, dev->broadcast, dev->addr_len);
 343			return 0;
 344		}
 345	}
 346	return -EINVAL;
 347}
 348
 349EXPORT_SYMBOL(ndisc_mc_map);
 350
 351static u32 ndisc_hash(const void *pkey,
 352		      const struct net_device *dev,
 353		      __u32 hash_rnd)
 354{
 355	const u32 *p32 = pkey;
 356	u32 addr_hash, i;
 357
 358	addr_hash = 0;
 359	for (i = 0; i < (sizeof(struct in6_addr) / sizeof(u32)); i++)
 360		addr_hash ^= *p32++;
 361
 362	return jhash_2words(addr_hash, dev->ifindex, hash_rnd);
 363}
 364
 365static int ndisc_constructor(struct neighbour *neigh)
 366{
 367	struct in6_addr *addr = (struct in6_addr*)&neigh->primary_key;
 368	struct net_device *dev = neigh->dev;
 369	struct inet6_dev *in6_dev;
 370	struct neigh_parms *parms;
 371	int is_multicast = ipv6_addr_is_multicast(addr);
 372
 373	rcu_read_lock();
 374	in6_dev = in6_dev_get(dev);
 375	if (in6_dev == NULL) {
 376		rcu_read_unlock();
 377		return -EINVAL;
 378	}
 379
 380	parms = in6_dev->nd_parms;
 381	__neigh_parms_put(neigh->parms);
 382	neigh->parms = neigh_parms_clone(parms);
 383	rcu_read_unlock();
 384
 385	neigh->type = is_multicast ? RTN_MULTICAST : RTN_UNICAST;
 386	if (!dev->header_ops) {
 387		neigh->nud_state = NUD_NOARP;
 388		neigh->ops = &ndisc_direct_ops;
 389		neigh->output = neigh_direct_output;
 390	} else {
 391		if (is_multicast) {
 392			neigh->nud_state = NUD_NOARP;
 393			ndisc_mc_map(addr, neigh->ha, dev, 1);
 394		} else if (dev->flags&(IFF_NOARP|IFF_LOOPBACK)) {
 395			neigh->nud_state = NUD_NOARP;
 396			memcpy(neigh->ha, dev->dev_addr, dev->addr_len);
 397			if (dev->flags&IFF_LOOPBACK)
 398				neigh->type = RTN_LOCAL;
 399		} else if (dev->flags&IFF_POINTOPOINT) {
 400			neigh->nud_state = NUD_NOARP;
 401			memcpy(neigh->ha, dev->broadcast, dev->addr_len);
 402		}
 403		if (dev->header_ops->cache)
 404			neigh->ops = &ndisc_hh_ops;
 405		else
 406			neigh->ops = &ndisc_generic_ops;
 407		if (neigh->nud_state&NUD_VALID)
 408			neigh->output = neigh->ops->connected_output;
 409		else
 410			neigh->output = neigh->ops->output;
 411	}
 412	in6_dev_put(in6_dev);
 413	return 0;
 414}
 415
 416static int pndisc_constructor(struct pneigh_entry *n)
 417{
 418	struct in6_addr *addr = (struct in6_addr*)&n->key;
 419	struct in6_addr maddr;
 420	struct net_device *dev = n->dev;
 421
 422	if (dev == NULL || __in6_dev_get(dev) == NULL)
 423		return -EINVAL;
 424	addrconf_addr_solict_mult(addr, &maddr);
 425	ipv6_dev_mc_inc(dev, &maddr);
 426	return 0;
 427}
 428
 429static void pndisc_destructor(struct pneigh_entry *n)
 430{
 431	struct in6_addr *addr = (struct in6_addr*)&n->key;
 432	struct in6_addr maddr;
 433	struct net_device *dev = n->dev;
 434
 435	if (dev == NULL || __in6_dev_get(dev) == NULL)
 436		return;
 437	addrconf_addr_solict_mult(addr, &maddr);
 438	ipv6_dev_mc_dec(dev, &maddr);
 439}
 440
 441struct sk_buff *ndisc_build_skb(struct net_device *dev,
 442				const struct in6_addr *daddr,
 443				const struct in6_addr *saddr,
 444				struct icmp6hdr *icmp6h,
 445				const struct in6_addr *target,
 446				int llinfo)
 447{
 448	struct net *net = dev_net(dev);
 449	struct sock *sk = net->ipv6.ndisc_sk;
 450	struct sk_buff *skb;
 451	struct icmp6hdr *hdr;
 
 
 452	int len;
 453	int err;
 454	u8 *opt;
 455
 456	if (!dev->addr_len)
 457		llinfo = 0;
 458
 459	len = sizeof(struct icmp6hdr) + (target ? sizeof(*target) : 0);
 460	if (llinfo)
 461		len += ndisc_opt_addr_space(dev);
 462
 463	skb = sock_alloc_send_skb(sk,
 464				  (MAX_HEADER + sizeof(struct ipv6hdr) +
 465				   len + LL_ALLOCATED_SPACE(dev)),
 466				  1, &err);
 467	if (!skb) {
 468		ND_PRINTK0(KERN_ERR
 469			   "ICMPv6 ND: %s() failed to allocate an skb, err=%d.\n",
 470			   __func__, err);
 471		return NULL;
 472	}
 473
 474	skb_reserve(skb, LL_RESERVED_SPACE(dev));
 475	ip6_nd_hdr(sk, skb, dev, saddr, daddr, IPPROTO_ICMPV6, len);
 476
 477	skb->transport_header = skb->tail;
 478	skb_put(skb, len);
 479
 480	hdr = (struct icmp6hdr *)skb_transport_header(skb);
 481	memcpy(hdr, icmp6h, sizeof(*hdr));
 482
 483	opt = skb_transport_header(skb) + sizeof(struct icmp6hdr);
 484	if (target) {
 485		ipv6_addr_copy((struct in6_addr *)opt, target);
 486		opt += sizeof(*target);
 487	}
 488
 489	if (llinfo)
 490		ndisc_fill_addr_option(opt, llinfo, dev->dev_addr,
 491				       dev->addr_len, dev->type);
 492
 493	hdr->icmp6_cksum = csum_ipv6_magic(saddr, daddr, len,
 494					   IPPROTO_ICMPV6,
 495					   csum_partial(hdr,
 496							len, 0));
 497
 498	return skb;
 499}
 500
 501EXPORT_SYMBOL(ndisc_build_skb);
 502
 503void ndisc_send_skb(struct sk_buff *skb,
 504		    struct net_device *dev,
 505		    struct neighbour *neigh,
 506		    const struct in6_addr *daddr,
 507		    const struct in6_addr *saddr,
 508		    struct icmp6hdr *icmp6h)
 509{
 510	struct flowi6 fl6;
 511	struct dst_entry *dst;
 512	struct net *net = dev_net(dev);
 513	struct sock *sk = net->ipv6.ndisc_sk;
 514	struct inet6_dev *idev;
 515	int err;
 516	u8 type;
 517
 518	type = icmp6h->icmp6_type;
 519
 520	icmpv6_flow_init(sk, &fl6, type, saddr, daddr, dev->ifindex);
 521
 522	dst = icmp6_dst_alloc(dev, neigh, daddr);
 523	if (!dst) {
 524		kfree_skb(skb);
 525		return;
 526	}
 527
 528	dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), NULL, 0);
 529	if (IS_ERR(dst)) {
 530		kfree_skb(skb);
 531		return;
 532	}
 533
 534	skb_dst_set(skb, dst);
 535
 536	idev = in6_dev_get(dst->dev);
 
 537	IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUT, skb->len);
 538
 539	err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT, skb, NULL, dst->dev,
 540		      dst_output);
 541	if (!err) {
 542		ICMP6MSGOUT_INC_STATS(net, idev, type);
 543		ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
 544	}
 545
 546	if (likely(idev != NULL))
 547		in6_dev_put(idev);
 548}
 549
 550EXPORT_SYMBOL(ndisc_send_skb);
 551
 552/*
 553 *	Send a Neighbour Discover packet
 554 */
 555static void __ndisc_send(struct net_device *dev,
 556			 struct neighbour *neigh,
 557			 const struct in6_addr *daddr,
 558			 const struct in6_addr *saddr,
 559			 struct icmp6hdr *icmp6h, const struct in6_addr *target,
 560			 int llinfo)
 561{
 562	struct sk_buff *skb;
 563
 564	skb = ndisc_build_skb(dev, daddr, saddr, icmp6h, target, llinfo);
 565	if (!skb)
 566		return;
 567
 568	ndisc_send_skb(skb, dev, neigh, daddr, saddr, icmp6h);
 569}
 570
 571static void ndisc_send_na(struct net_device *dev, struct neighbour *neigh,
 572			  const struct in6_addr *daddr,
 573			  const struct in6_addr *solicited_addr,
 574			  int router, int solicited, int override, int inc_opt)
 575{
 576	struct in6_addr tmpaddr;
 577	struct inet6_ifaddr *ifp;
 578	const struct in6_addr *src_addr;
 579	struct icmp6hdr icmp6h = {
 580		.icmp6_type = NDISC_NEIGHBOUR_ADVERTISEMENT,
 581	};
 582
 583	/* for anycast or proxy, solicited_addr != src_addr */
 584	ifp = ipv6_get_ifaddr(dev_net(dev), solicited_addr, dev, 1);
 585	if (ifp) {
 586		src_addr = solicited_addr;
 587		if (ifp->flags & IFA_F_OPTIMISTIC)
 588			override = 0;
 589		inc_opt |= ifp->idev->cnf.force_tllao;
 590		in6_ifa_put(ifp);
 591	} else {
 592		if (ipv6_dev_get_saddr(dev_net(dev), dev, daddr,
 593				       inet6_sk(dev_net(dev)->ipv6.ndisc_sk)->srcprefs,
 594				       &tmpaddr))
 595			return;
 596		src_addr = &tmpaddr;
 597	}
 598
 599	icmp6h.icmp6_router = router;
 600	icmp6h.icmp6_solicited = solicited;
 601	icmp6h.icmp6_override = override;
 602
 603	__ndisc_send(dev, neigh, daddr, src_addr,
 604		     &icmp6h, solicited_addr,
 605		     inc_opt ? ND_OPT_TARGET_LL_ADDR : 0);
 606}
 607
 608static void ndisc_send_unsol_na(struct net_device *dev)
 609{
 610	struct inet6_dev *idev;
 611	struct inet6_ifaddr *ifa;
 612	struct in6_addr mcaddr;
 613
 614	idev = in6_dev_get(dev);
 615	if (!idev)
 616		return;
 617
 618	read_lock_bh(&idev->lock);
 619	list_for_each_entry(ifa, &idev->addr_list, if_list) {
 620		addrconf_addr_solict_mult(&ifa->addr, &mcaddr);
 621		ndisc_send_na(dev, NULL, &mcaddr, &ifa->addr,
 622			      /*router=*/ !!idev->cnf.forwarding,
 623			      /*solicited=*/ false, /*override=*/ true,
 624			      /*inc_opt=*/ true);
 625	}
 626	read_unlock_bh(&idev->lock);
 627
 628	in6_dev_put(idev);
 629}
 630
 631void ndisc_send_ns(struct net_device *dev, struct neighbour *neigh,
 632		   const struct in6_addr *solicit,
 633		   const struct in6_addr *daddr, const struct in6_addr *saddr)
 634{
 635	struct in6_addr addr_buf;
 636	struct icmp6hdr icmp6h = {
 637		.icmp6_type = NDISC_NEIGHBOUR_SOLICITATION,
 638	};
 639
 640	if (saddr == NULL) {
 641		if (ipv6_get_lladdr(dev, &addr_buf,
 642				   (IFA_F_TENTATIVE|IFA_F_OPTIMISTIC)))
 643			return;
 644		saddr = &addr_buf;
 645	}
 646
 647	__ndisc_send(dev, neigh, daddr, saddr,
 648		     &icmp6h, solicit,
 649		     !ipv6_addr_any(saddr) ? ND_OPT_SOURCE_LL_ADDR : 0);
 650}
 651
 652void ndisc_send_rs(struct net_device *dev, const struct in6_addr *saddr,
 653		   const struct in6_addr *daddr)
 654{
 655	struct icmp6hdr icmp6h = {
 656		.icmp6_type = NDISC_ROUTER_SOLICITATION,
 657	};
 658	int send_sllao = dev->addr_len;
 659
 660#ifdef CONFIG_IPV6_OPTIMISTIC_DAD
 661	/*
 662	 * According to section 2.2 of RFC 4429, we must not
 663	 * send router solicitations with a sllao from
 664	 * optimistic addresses, but we may send the solicitation
 665	 * if we don't include the sllao.  So here we check
 666	 * if our address is optimistic, and if so, we
 667	 * suppress the inclusion of the sllao.
 668	 */
 669	if (send_sllao) {
 670		struct inet6_ifaddr *ifp = ipv6_get_ifaddr(dev_net(dev), saddr,
 671							   dev, 1);
 672		if (ifp) {
 673			if (ifp->flags & IFA_F_OPTIMISTIC)  {
 674				send_sllao = 0;
 675			}
 676			in6_ifa_put(ifp);
 677		} else {
 678			send_sllao = 0;
 679		}
 680	}
 681#endif
 682	__ndisc_send(dev, NULL, daddr, saddr,
 683		     &icmp6h, NULL,
 684		     send_sllao ? ND_OPT_SOURCE_LL_ADDR : 0);
 685}
 686
 687
 688static void ndisc_error_report(struct neighbour *neigh, struct sk_buff *skb)
 689{
 690	/*
 691	 *	"The sender MUST return an ICMP
 692	 *	 destination unreachable"
 693	 */
 694	dst_link_failure(skb);
 695	kfree_skb(skb);
 696}
 697
 698/* Called with locked neigh: either read or both */
 699
 700static void ndisc_solicit(struct neighbour *neigh, struct sk_buff *skb)
 701{
 702	struct in6_addr *saddr = NULL;
 703	struct in6_addr mcaddr;
 704	struct net_device *dev = neigh->dev;
 705	struct in6_addr *target = (struct in6_addr *)&neigh->primary_key;
 706	int probes = atomic_read(&neigh->probes);
 707
 708	if (skb && ipv6_chk_addr(dev_net(dev), &ipv6_hdr(skb)->saddr, dev, 1))
 709		saddr = &ipv6_hdr(skb)->saddr;
 710
 711	if ((probes -= neigh->parms->ucast_probes) < 0) {
 712		if (!(neigh->nud_state & NUD_VALID)) {
 713			ND_PRINTK1(KERN_DEBUG "%s(): trying to ucast probe in NUD_INVALID: %pI6\n",
 714				   __func__, target);
 
 715		}
 716		ndisc_send_ns(dev, neigh, target, target, saddr);
 717	} else if ((probes -= neigh->parms->app_probes) < 0) {
 718#ifdef CONFIG_ARPD
 719		neigh_app_ns(neigh);
 720#endif
 721	} else {
 722		addrconf_addr_solict_mult(target, &mcaddr);
 723		ndisc_send_ns(dev, NULL, target, &mcaddr, saddr);
 724	}
 725}
 726
 727static int pndisc_is_router(const void *pkey,
 728			    struct net_device *dev)
 729{
 730	struct pneigh_entry *n;
 731	int ret = -1;
 732
 733	read_lock_bh(&nd_tbl.lock);
 734	n = __pneigh_lookup(&nd_tbl, dev_net(dev), pkey, dev);
 735	if (n)
 736		ret = !!(n->flags & NTF_ROUTER);
 737	read_unlock_bh(&nd_tbl.lock);
 738
 739	return ret;
 740}
 741
 742static void ndisc_recv_ns(struct sk_buff *skb)
 743{
 744	struct nd_msg *msg = (struct nd_msg *)skb_transport_header(skb);
 745	const struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
 746	const struct in6_addr *daddr = &ipv6_hdr(skb)->daddr;
 747	u8 *lladdr = NULL;
 748	u32 ndoptlen = skb->tail - (skb->transport_header +
 749				    offsetof(struct nd_msg, opt));
 750	struct ndisc_options ndopts;
 751	struct net_device *dev = skb->dev;
 752	struct inet6_ifaddr *ifp;
 753	struct inet6_dev *idev = NULL;
 754	struct neighbour *neigh;
 755	int dad = ipv6_addr_any(saddr);
 756	int inc;
 757	int is_router = -1;
 758
 759	if (ipv6_addr_is_multicast(&msg->target)) {
 760		ND_PRINTK2(KERN_WARNING
 761			   "ICMPv6 NS: multicast target address");
 762		return;
 763	}
 764
 765	/*
 766	 * RFC2461 7.1.1:
 767	 * DAD has to be destined for solicited node multicast address.
 768	 */
 769	if (dad &&
 770	    !(daddr->s6_addr32[0] == htonl(0xff020000) &&
 771	      daddr->s6_addr32[1] == htonl(0x00000000) &&
 772	      daddr->s6_addr32[2] == htonl(0x00000001) &&
 773	      daddr->s6_addr [12] == 0xff )) {
 774		ND_PRINTK2(KERN_WARNING
 775			   "ICMPv6 NS: bad DAD packet (wrong destination)\n");
 776		return;
 777	}
 778
 779	if (!ndisc_parse_options(msg->opt, ndoptlen, &ndopts)) {
 780		ND_PRINTK2(KERN_WARNING
 781			   "ICMPv6 NS: invalid ND options\n");
 782		return;
 783	}
 784
 785	if (ndopts.nd_opts_src_lladdr) {
 786		lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr, dev);
 787		if (!lladdr) {
 788			ND_PRINTK2(KERN_WARNING
 789				   "ICMPv6 NS: invalid link-layer address length\n");
 790			return;
 791		}
 792
 793		/* RFC2461 7.1.1:
 794		 *	If the IP source address is the unspecified address,
 795		 *	there MUST NOT be source link-layer address option
 796		 *	in the message.
 797		 */
 798		if (dad) {
 799			ND_PRINTK2(KERN_WARNING
 800				   "ICMPv6 NS: bad DAD packet (link-layer address option)\n");
 801			return;
 802		}
 803	}
 804
 805	inc = ipv6_addr_is_multicast(daddr);
 806
 807	ifp = ipv6_get_ifaddr(dev_net(dev), &msg->target, dev, 1);
 808	if (ifp) {
 809
 810		if (ifp->flags & (IFA_F_TENTATIVE|IFA_F_OPTIMISTIC)) {
 811			if (dad) {
 812				if (dev->type == ARPHRD_IEEE802_TR) {
 813					const unsigned char *sadr;
 814					sadr = skb_mac_header(skb);
 815					if (((sadr[8] ^ dev->dev_addr[0]) & 0x7f) == 0 &&
 816					    sadr[9] == dev->dev_addr[1] &&
 817					    sadr[10] == dev->dev_addr[2] &&
 818					    sadr[11] == dev->dev_addr[3] &&
 819					    sadr[12] == dev->dev_addr[4] &&
 820					    sadr[13] == dev->dev_addr[5]) {
 821						/* looped-back to us */
 822						goto out;
 823					}
 824				}
 825
 826				/*
 827				 * We are colliding with another node
 828				 * who is doing DAD
 829				 * so fail our DAD process
 830				 */
 831				addrconf_dad_failure(ifp);
 832				return;
 833			} else {
 834				/*
 835				 * This is not a dad solicitation.
 836				 * If we are an optimistic node,
 837				 * we should respond.
 838				 * Otherwise, we should ignore it.
 839				 */
 840				if (!(ifp->flags & IFA_F_OPTIMISTIC))
 841					goto out;
 842			}
 843		}
 844
 845		idev = ifp->idev;
 846	} else {
 847		struct net *net = dev_net(dev);
 848
 849		idev = in6_dev_get(dev);
 850		if (!idev) {
 851			/* XXX: count this drop? */
 852			return;
 853		}
 854
 855		if (ipv6_chk_acast_addr(net, dev, &msg->target) ||
 856		    (idev->cnf.forwarding &&
 857		     (net->ipv6.devconf_all->proxy_ndp || idev->cnf.proxy_ndp) &&
 858		     (is_router = pndisc_is_router(&msg->target, dev)) >= 0)) {
 859			if (!(NEIGH_CB(skb)->flags & LOCALLY_ENQUEUED) &&
 860			    skb->pkt_type != PACKET_HOST &&
 861			    inc != 0 &&
 862			    idev->nd_parms->proxy_delay != 0) {
 863				/*
 864				 * for anycast or proxy,
 865				 * sender should delay its response
 866				 * by a random time between 0 and
 867				 * MAX_ANYCAST_DELAY_TIME seconds.
 868				 * (RFC2461) -- yoshfuji
 869				 */
 870				struct sk_buff *n = skb_clone(skb, GFP_ATOMIC);
 871				if (n)
 872					pneigh_enqueue(&nd_tbl, idev->nd_parms, n);
 873				goto out;
 874			}
 875		} else
 876			goto out;
 877	}
 878
 879	if (is_router < 0)
 880		is_router = !!idev->cnf.forwarding;
 881
 882	if (dad) {
 883		ndisc_send_na(dev, NULL, &in6addr_linklocal_allnodes, &msg->target,
 884			      is_router, 0, (ifp != NULL), 1);
 885		goto out;
 886	}
 887
 888	if (inc)
 889		NEIGH_CACHE_STAT_INC(&nd_tbl, rcv_probes_mcast);
 890	else
 891		NEIGH_CACHE_STAT_INC(&nd_tbl, rcv_probes_ucast);
 892
 893	/*
 894	 *	update / create cache entry
 895	 *	for the source address
 896	 */
 897	neigh = __neigh_lookup(&nd_tbl, saddr, dev,
 898			       !inc || lladdr || !dev->addr_len);
 899	if (neigh)
 900		neigh_update(neigh, lladdr, NUD_STALE,
 901			     NEIGH_UPDATE_F_WEAK_OVERRIDE|
 902			     NEIGH_UPDATE_F_OVERRIDE);
 903	if (neigh || !dev->header_ops) {
 904		ndisc_send_na(dev, neigh, saddr, &msg->target,
 905			      is_router,
 906			      1, (ifp != NULL && inc), inc);
 907		if (neigh)
 908			neigh_release(neigh);
 909	}
 910
 911out:
 912	if (ifp)
 913		in6_ifa_put(ifp);
 914	else
 915		in6_dev_put(idev);
 916}
 917
 918static void ndisc_recv_na(struct sk_buff *skb)
 919{
 920	struct nd_msg *msg = (struct nd_msg *)skb_transport_header(skb);
 921	const struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
 922	const struct in6_addr *daddr = &ipv6_hdr(skb)->daddr;
 923	u8 *lladdr = NULL;
 924	u32 ndoptlen = skb->tail - (skb->transport_header +
 925				    offsetof(struct nd_msg, opt));
 926	struct ndisc_options ndopts;
 927	struct net_device *dev = skb->dev;
 928	struct inet6_ifaddr *ifp;
 929	struct neighbour *neigh;
 930
 931	if (skb->len < sizeof(struct nd_msg)) {
 932		ND_PRINTK2(KERN_WARNING
 933			   "ICMPv6 NA: packet too short\n");
 934		return;
 935	}
 936
 937	if (ipv6_addr_is_multicast(&msg->target)) {
 938		ND_PRINTK2(KERN_WARNING
 939			   "ICMPv6 NA: target address is multicast.\n");
 940		return;
 941	}
 942
 943	if (ipv6_addr_is_multicast(daddr) &&
 944	    msg->icmph.icmp6_solicited) {
 945		ND_PRINTK2(KERN_WARNING
 946			   "ICMPv6 NA: solicited NA is multicasted.\n");
 947		return;
 948	}
 949
 950	if (!ndisc_parse_options(msg->opt, ndoptlen, &ndopts)) {
 951		ND_PRINTK2(KERN_WARNING
 952			   "ICMPv6 NS: invalid ND option\n");
 953		return;
 954	}
 955	if (ndopts.nd_opts_tgt_lladdr) {
 956		lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr, dev);
 957		if (!lladdr) {
 958			ND_PRINTK2(KERN_WARNING
 959				   "ICMPv6 NA: invalid link-layer address length\n");
 960			return;
 961		}
 962	}
 963	ifp = ipv6_get_ifaddr(dev_net(dev), &msg->target, dev, 1);
 964	if (ifp) {
 965		if (skb->pkt_type != PACKET_LOOPBACK
 966		    && (ifp->flags & IFA_F_TENTATIVE)) {
 967				addrconf_dad_failure(ifp);
 968				return;
 969		}
 970		/* What should we make now? The advertisement
 971		   is invalid, but ndisc specs say nothing
 972		   about it. It could be misconfiguration, or
 973		   an smart proxy agent tries to help us :-)
 974
 975		   We should not print the error if NA has been
 976		   received from loopback - it is just our own
 977		   unsolicited advertisement.
 978		 */
 979		if (skb->pkt_type != PACKET_LOOPBACK)
 980			ND_PRINTK1(KERN_WARNING
 981			   "ICMPv6 NA: someone advertises our address %pI6 on %s!\n",
 982			   &ifp->addr, ifp->idev->dev->name);
 983		in6_ifa_put(ifp);
 984		return;
 985	}
 986	neigh = neigh_lookup(&nd_tbl, &msg->target, dev);
 987
 988	if (neigh) {
 989		u8 old_flags = neigh->flags;
 990		struct net *net = dev_net(dev);
 991
 992		if (neigh->nud_state & NUD_FAILED)
 993			goto out;
 994
 995		/*
 996		 * Don't update the neighbor cache entry on a proxy NA from
 997		 * ourselves because either the proxied node is off link or it
 998		 * has already sent a NA to us.
 999		 */
1000		if (lladdr && !memcmp(lladdr, dev->dev_addr, dev->addr_len) &&
1001		    net->ipv6.devconf_all->forwarding && net->ipv6.devconf_all->proxy_ndp &&
1002		    pneigh_lookup(&nd_tbl, net, &msg->target, dev, 0)) {
1003			/* XXX: idev->cnf.prixy_ndp */
1004			goto out;
1005		}
1006
1007		neigh_update(neigh, lladdr,
1008			     msg->icmph.icmp6_solicited ? NUD_REACHABLE : NUD_STALE,
1009			     NEIGH_UPDATE_F_WEAK_OVERRIDE|
1010			     (msg->icmph.icmp6_override ? NEIGH_UPDATE_F_OVERRIDE : 0)|
1011			     NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
1012			     (msg->icmph.icmp6_router ? NEIGH_UPDATE_F_ISROUTER : 0));
1013
1014		if ((old_flags & ~neigh->flags) & NTF_ROUTER) {
1015			/*
1016			 * Change: router to host
1017			 */
1018			struct rt6_info *rt;
1019			rt = rt6_get_dflt_router(saddr, dev);
1020			if (rt)
1021				ip6_del_rt(rt);
1022		}
1023
1024out:
1025		neigh_release(neigh);
1026	}
1027}
1028
1029static void ndisc_recv_rs(struct sk_buff *skb)
1030{
1031	struct rs_msg *rs_msg = (struct rs_msg *)skb_transport_header(skb);
1032	unsigned long ndoptlen = skb->len - sizeof(*rs_msg);
1033	struct neighbour *neigh;
1034	struct inet6_dev *idev;
1035	const struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
1036	struct ndisc_options ndopts;
1037	u8 *lladdr = NULL;
1038
1039	if (skb->len < sizeof(*rs_msg))
1040		return;
1041
1042	idev = in6_dev_get(skb->dev);
1043	if (!idev) {
1044		if (net_ratelimit())
1045			ND_PRINTK1("ICMP6 RS: can't find in6 device\n");
1046		return;
1047	}
1048
1049	/* Don't accept RS if we're not in router mode */
1050	if (!idev->cnf.forwarding)
1051		goto out;
1052
1053	/*
1054	 * Don't update NCE if src = ::;
1055	 * this implies that the source node has no ip address assigned yet.
1056	 */
1057	if (ipv6_addr_any(saddr))
1058		goto out;
1059
1060	/* Parse ND options */
1061	if (!ndisc_parse_options(rs_msg->opt, ndoptlen, &ndopts)) {
1062		if (net_ratelimit())
1063			ND_PRINTK2("ICMP6 NS: invalid ND option, ignored\n");
1064		goto out;
1065	}
1066
1067	if (ndopts.nd_opts_src_lladdr) {
1068		lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr,
1069					     skb->dev);
1070		if (!lladdr)
1071			goto out;
1072	}
1073
1074	neigh = __neigh_lookup(&nd_tbl, saddr, skb->dev, 1);
1075	if (neigh) {
1076		neigh_update(neigh, lladdr, NUD_STALE,
1077			     NEIGH_UPDATE_F_WEAK_OVERRIDE|
1078			     NEIGH_UPDATE_F_OVERRIDE|
1079			     NEIGH_UPDATE_F_OVERRIDE_ISROUTER);
1080		neigh_release(neigh);
1081	}
1082out:
1083	in6_dev_put(idev);
1084}
1085
1086static void ndisc_ra_useropt(struct sk_buff *ra, struct nd_opt_hdr *opt)
1087{
1088	struct icmp6hdr *icmp6h = (struct icmp6hdr *)skb_transport_header(ra);
1089	struct sk_buff *skb;
1090	struct nlmsghdr *nlh;
1091	struct nduseroptmsg *ndmsg;
1092	struct net *net = dev_net(ra->dev);
1093	int err;
1094	int base_size = NLMSG_ALIGN(sizeof(struct nduseroptmsg)
1095				    + (opt->nd_opt_len << 3));
1096	size_t msg_size = base_size + nla_total_size(sizeof(struct in6_addr));
1097
1098	skb = nlmsg_new(msg_size, GFP_ATOMIC);
1099	if (skb == NULL) {
1100		err = -ENOBUFS;
1101		goto errout;
1102	}
1103
1104	nlh = nlmsg_put(skb, 0, 0, RTM_NEWNDUSEROPT, base_size, 0);
1105	if (nlh == NULL) {
1106		goto nla_put_failure;
1107	}
1108
1109	ndmsg = nlmsg_data(nlh);
1110	ndmsg->nduseropt_family = AF_INET6;
1111	ndmsg->nduseropt_ifindex = ra->dev->ifindex;
1112	ndmsg->nduseropt_icmp_type = icmp6h->icmp6_type;
1113	ndmsg->nduseropt_icmp_code = icmp6h->icmp6_code;
1114	ndmsg->nduseropt_opts_len = opt->nd_opt_len << 3;
1115
1116	memcpy(ndmsg + 1, opt, opt->nd_opt_len << 3);
1117
1118	NLA_PUT(skb, NDUSEROPT_SRCADDR, sizeof(struct in6_addr),
1119		&ipv6_hdr(ra)->saddr);
 
1120	nlmsg_end(skb, nlh);
1121
1122	rtnl_notify(skb, net, 0, RTNLGRP_ND_USEROPT, NULL, GFP_ATOMIC);
1123	return;
1124
1125nla_put_failure:
1126	nlmsg_free(skb);
1127	err = -EMSGSIZE;
1128errout:
1129	rtnl_set_sk_err(net, RTNLGRP_ND_USEROPT, err);
1130}
1131
1132static inline int accept_ra(struct inet6_dev *in6_dev)
1133{
1134	/*
1135	 * If forwarding is enabled, RA are not accepted unless the special
1136	 * hybrid mode (accept_ra=2) is enabled.
1137	 */
1138	if (in6_dev->cnf.forwarding && in6_dev->cnf.accept_ra < 2)
1139		return 0;
1140
1141	return in6_dev->cnf.accept_ra;
1142}
1143
1144static void ndisc_router_discovery(struct sk_buff *skb)
1145{
1146	struct ra_msg *ra_msg = (struct ra_msg *)skb_transport_header(skb);
1147	struct neighbour *neigh = NULL;
1148	struct inet6_dev *in6_dev;
1149	struct rt6_info *rt = NULL;
1150	int lifetime;
1151	struct ndisc_options ndopts;
1152	int optlen;
1153	unsigned int pref = 0;
1154
1155	__u8 * opt = (__u8 *)(ra_msg + 1);
1156
1157	optlen = (skb->tail - skb->transport_header) - sizeof(struct ra_msg);
1158
1159	if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) {
1160		ND_PRINTK2(KERN_WARNING
1161			   "ICMPv6 RA: source address is not link-local.\n");
1162		return;
1163	}
1164	if (optlen < 0) {
1165		ND_PRINTK2(KERN_WARNING
1166			   "ICMPv6 RA: packet too short\n");
1167		return;
1168	}
1169
1170#ifdef CONFIG_IPV6_NDISC_NODETYPE
1171	if (skb->ndisc_nodetype == NDISC_NODETYPE_HOST) {
1172		ND_PRINTK2(KERN_WARNING
1173			   "ICMPv6 RA: from host or unauthorized router\n");
1174		return;
1175	}
1176#endif
1177
1178	/*
1179	 *	set the RA_RECV flag in the interface
1180	 */
1181
1182	in6_dev = in6_dev_get(skb->dev);
1183	if (in6_dev == NULL) {
1184		ND_PRINTK0(KERN_ERR
1185			   "ICMPv6 RA: can't find inet6 device for %s.\n",
1186			   skb->dev->name);
1187		return;
1188	}
1189
1190	if (!ndisc_parse_options(opt, optlen, &ndopts)) {
1191		in6_dev_put(in6_dev);
1192		ND_PRINTK2(KERN_WARNING
1193			   "ICMP6 RA: invalid ND options\n");
1194		return;
1195	}
1196
1197	if (!accept_ra(in6_dev))
1198		goto skip_linkparms;
1199
1200#ifdef CONFIG_IPV6_NDISC_NODETYPE
1201	/* skip link-specific parameters from interior routers */
1202	if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT)
1203		goto skip_linkparms;
1204#endif
1205
1206	if (in6_dev->if_flags & IF_RS_SENT) {
1207		/*
1208		 *	flag that an RA was received after an RS was sent
1209		 *	out on this interface.
1210		 */
1211		in6_dev->if_flags |= IF_RA_RCVD;
1212	}
1213
1214	/*
1215	 * Remember the managed/otherconf flags from most recently
1216	 * received RA message (RFC 2462) -- yoshfuji
1217	 */
1218	in6_dev->if_flags = (in6_dev->if_flags & ~(IF_RA_MANAGED |
1219				IF_RA_OTHERCONF)) |
1220				(ra_msg->icmph.icmp6_addrconf_managed ?
1221					IF_RA_MANAGED : 0) |
1222				(ra_msg->icmph.icmp6_addrconf_other ?
1223					IF_RA_OTHERCONF : 0);
1224
1225	if (!in6_dev->cnf.accept_ra_defrtr)
1226		goto skip_defrtr;
1227
 
 
 
1228	lifetime = ntohs(ra_msg->icmph.icmp6_rt_lifetime);
1229
1230#ifdef CONFIG_IPV6_ROUTER_PREF
1231	pref = ra_msg->icmph.icmp6_router_pref;
1232	/* 10b is handled as if it were 00b (medium) */
1233	if (pref == ICMPV6_ROUTER_PREF_INVALID ||
1234	    !in6_dev->cnf.accept_ra_rtr_pref)
1235		pref = ICMPV6_ROUTER_PREF_MEDIUM;
1236#endif
1237
1238	rt = rt6_get_dflt_router(&ipv6_hdr(skb)->saddr, skb->dev);
1239
1240	if (rt)
1241		neigh = dst_get_neighbour(&rt->dst);
1242
 
 
 
 
 
 
 
1243	if (rt && lifetime == 0) {
1244		neigh_clone(neigh);
1245		ip6_del_rt(rt);
1246		rt = NULL;
1247	}
1248
1249	if (rt == NULL && lifetime) {
1250		ND_PRINTK3(KERN_DEBUG
1251			   "ICMPv6 RA: adding default router.\n");
1252
1253		rt = rt6_add_dflt_router(&ipv6_hdr(skb)->saddr, skb->dev, pref);
1254		if (rt == NULL) {
1255			ND_PRINTK0(KERN_ERR
1256				   "ICMPv6 RA: %s() failed to add default route.\n",
1257				   __func__);
1258			in6_dev_put(in6_dev);
1259			return;
1260		}
1261
1262		neigh = dst_get_neighbour(&rt->dst);
1263		if (neigh == NULL) {
1264			ND_PRINTK0(KERN_ERR
1265				   "ICMPv6 RA: %s() got default router without neighbour.\n",
1266				   __func__);
1267			dst_release(&rt->dst);
1268			in6_dev_put(in6_dev);
1269			return;
1270		}
1271		neigh->flags |= NTF_ROUTER;
1272	} else if (rt) {
1273		rt->rt6i_flags = (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
1274	}
1275
1276	if (rt)
1277		rt->rt6i_expires = jiffies + (HZ * lifetime);
1278
1279	if (ra_msg->icmph.icmp6_hop_limit) {
1280		in6_dev->cnf.hop_limit = ra_msg->icmph.icmp6_hop_limit;
1281		if (rt)
1282			dst_metric_set(&rt->dst, RTAX_HOPLIMIT,
1283				       ra_msg->icmph.icmp6_hop_limit);
1284	}
1285
1286skip_defrtr:
1287
1288	/*
1289	 *	Update Reachable Time and Retrans Timer
1290	 */
1291
1292	if (in6_dev->nd_parms) {
1293		unsigned long rtime = ntohl(ra_msg->retrans_timer);
1294
1295		if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/HZ) {
1296			rtime = (rtime*HZ)/1000;
1297			if (rtime < HZ/10)
1298				rtime = HZ/10;
1299			in6_dev->nd_parms->retrans_time = rtime;
1300			in6_dev->tstamp = jiffies;
1301			inet6_ifinfo_notify(RTM_NEWLINK, in6_dev);
1302		}
1303
1304		rtime = ntohl(ra_msg->reachable_time);
1305		if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/(3*HZ)) {
1306			rtime = (rtime*HZ)/1000;
1307
1308			if (rtime < HZ/10)
1309				rtime = HZ/10;
1310
1311			if (rtime != in6_dev->nd_parms->base_reachable_time) {
1312				in6_dev->nd_parms->base_reachable_time = rtime;
1313				in6_dev->nd_parms->gc_staletime = 3 * rtime;
1314				in6_dev->nd_parms->reachable_time = neigh_rand_reach_time(rtime);
1315				in6_dev->tstamp = jiffies;
1316				inet6_ifinfo_notify(RTM_NEWLINK, in6_dev);
1317			}
1318		}
1319	}
1320
1321skip_linkparms:
1322
1323	/*
1324	 *	Process options.
1325	 */
1326
1327	if (!neigh)
1328		neigh = __neigh_lookup(&nd_tbl, &ipv6_hdr(skb)->saddr,
1329				       skb->dev, 1);
1330	if (neigh) {
1331		u8 *lladdr = NULL;
1332		if (ndopts.nd_opts_src_lladdr) {
1333			lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr,
1334						     skb->dev);
1335			if (!lladdr) {
1336				ND_PRINTK2(KERN_WARNING
1337					   "ICMPv6 RA: invalid link-layer address length\n");
1338				goto out;
1339			}
1340		}
1341		neigh_update(neigh, lladdr, NUD_STALE,
1342			     NEIGH_UPDATE_F_WEAK_OVERRIDE|
1343			     NEIGH_UPDATE_F_OVERRIDE|
1344			     NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
1345			     NEIGH_UPDATE_F_ISROUTER);
1346	}
1347
1348	if (!accept_ra(in6_dev))
1349		goto out;
1350
1351#ifdef CONFIG_IPV6_ROUTE_INFO
 
 
 
1352	if (in6_dev->cnf.accept_ra_rtr_pref && ndopts.nd_opts_ri) {
1353		struct nd_opt_hdr *p;
1354		for (p = ndopts.nd_opts_ri;
1355		     p;
1356		     p = ndisc_next_option(p, ndopts.nd_opts_ri_end)) {
1357			struct route_info *ri = (struct route_info *)p;
1358#ifdef CONFIG_IPV6_NDISC_NODETYPE
1359			if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT &&
1360			    ri->prefix_len == 0)
1361				continue;
1362#endif
1363			if (ri->prefix_len > in6_dev->cnf.accept_ra_rt_info_max_plen)
1364				continue;
1365			rt6_route_rcv(skb->dev, (u8*)p, (p->nd_opt_len) << 3,
1366				      &ipv6_hdr(skb)->saddr);
1367		}
1368	}
 
 
1369#endif
1370
1371#ifdef CONFIG_IPV6_NDISC_NODETYPE
1372	/* skip link-specific ndopts from interior routers */
1373	if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT)
1374		goto out;
1375#endif
1376
1377	if (in6_dev->cnf.accept_ra_pinfo && ndopts.nd_opts_pi) {
1378		struct nd_opt_hdr *p;
1379		for (p = ndopts.nd_opts_pi;
1380		     p;
1381		     p = ndisc_next_option(p, ndopts.nd_opts_pi_end)) {
1382			addrconf_prefix_rcv(skb->dev, (u8*)p, (p->nd_opt_len) << 3);
 
 
1383		}
1384	}
1385
1386	if (ndopts.nd_opts_mtu) {
1387		__be32 n;
1388		u32 mtu;
1389
1390		memcpy(&n, ((u8*)(ndopts.nd_opts_mtu+1))+2, sizeof(mtu));
1391		mtu = ntohl(n);
1392
1393		if (mtu < IPV6_MIN_MTU || mtu > skb->dev->mtu) {
1394			ND_PRINTK2(KERN_WARNING
1395				   "ICMPv6 RA: invalid mtu: %d\n",
1396				   mtu);
1397		} else if (in6_dev->cnf.mtu6 != mtu) {
1398			in6_dev->cnf.mtu6 = mtu;
1399
1400			if (rt)
1401				dst_metric_set(&rt->dst, RTAX_MTU, mtu);
1402
1403			rt6_mtu_change(skb->dev, mtu);
1404		}
1405	}
1406
1407	if (ndopts.nd_useropts) {
1408		struct nd_opt_hdr *p;
1409		for (p = ndopts.nd_useropts;
1410		     p;
1411		     p = ndisc_next_useropt(p, ndopts.nd_useropts_end)) {
1412			ndisc_ra_useropt(skb, p);
1413		}
1414	}
1415
1416	if (ndopts.nd_opts_tgt_lladdr || ndopts.nd_opts_rh) {
1417		ND_PRINTK2(KERN_WARNING
1418			   "ICMPv6 RA: invalid RA options");
1419	}
1420out:
1421	if (rt)
1422		dst_release(&rt->dst);
1423	else if (neigh)
1424		neigh_release(neigh);
1425	in6_dev_put(in6_dev);
1426}
1427
1428static void ndisc_redirect_rcv(struct sk_buff *skb)
1429{
1430	struct inet6_dev *in6_dev;
1431	struct icmp6hdr *icmph;
1432	const struct in6_addr *dest;
1433	const struct in6_addr *target;	/* new first hop to destination */
1434	struct neighbour *neigh;
1435	int on_link = 0;
1436	struct ndisc_options ndopts;
1437	int optlen;
1438	u8 *lladdr = NULL;
1439
1440#ifdef CONFIG_IPV6_NDISC_NODETYPE
1441	switch (skb->ndisc_nodetype) {
1442	case NDISC_NODETYPE_HOST:
1443	case NDISC_NODETYPE_NODEFAULT:
1444		ND_PRINTK2(KERN_WARNING
1445			   "ICMPv6 Redirect: from host or unauthorized router\n");
1446		return;
1447	}
1448#endif
1449
1450	if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) {
1451		ND_PRINTK2(KERN_WARNING
1452			   "ICMPv6 Redirect: source address is not link-local.\n");
1453		return;
1454	}
1455
1456	optlen = skb->tail - skb->transport_header;
1457	optlen -= sizeof(struct icmp6hdr) + 2 * sizeof(struct in6_addr);
1458
1459	if (optlen < 0) {
1460		ND_PRINTK2(KERN_WARNING
1461			   "ICMPv6 Redirect: packet too short\n");
1462		return;
1463	}
1464
1465	icmph = icmp6_hdr(skb);
1466	target = (const struct in6_addr *) (icmph + 1);
1467	dest = target + 1;
1468
1469	if (ipv6_addr_is_multicast(dest)) {
1470		ND_PRINTK2(KERN_WARNING
1471			   "ICMPv6 Redirect: destination address is multicast.\n");
1472		return;
1473	}
1474
1475	if (ipv6_addr_equal(dest, target)) {
1476		on_link = 1;
1477	} else if (ipv6_addr_type(target) !=
1478		   (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
1479		ND_PRINTK2(KERN_WARNING
1480			   "ICMPv6 Redirect: target address is not link-local unicast.\n");
1481		return;
1482	}
1483
1484	in6_dev = in6_dev_get(skb->dev);
1485	if (!in6_dev)
1486		return;
1487	if (in6_dev->cnf.forwarding || !in6_dev->cnf.accept_redirects) {
1488		in6_dev_put(in6_dev);
1489		return;
1490	}
1491
1492	/* RFC2461 8.1:
1493	 *	The IP source address of the Redirect MUST be the same as the current
1494	 *	first-hop router for the specified ICMP Destination Address.
1495	 */
1496
1497	if (!ndisc_parse_options((u8*)(dest + 1), optlen, &ndopts)) {
1498		ND_PRINTK2(KERN_WARNING
1499			   "ICMPv6 Redirect: invalid ND options\n");
1500		in6_dev_put(in6_dev);
1501		return;
1502	}
1503	if (ndopts.nd_opts_tgt_lladdr) {
1504		lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr,
1505					     skb->dev);
1506		if (!lladdr) {
1507			ND_PRINTK2(KERN_WARNING
1508				   "ICMPv6 Redirect: invalid link-layer address length\n");
1509			in6_dev_put(in6_dev);
1510			return;
1511		}
1512	}
1513
1514	neigh = __neigh_lookup(&nd_tbl, target, skb->dev, 1);
1515	if (neigh) {
1516		rt6_redirect(dest, &ipv6_hdr(skb)->daddr,
1517			     &ipv6_hdr(skb)->saddr, neigh, lladdr,
1518			     on_link);
1519		neigh_release(neigh);
1520	}
1521	in6_dev_put(in6_dev);
1522}
1523
1524void ndisc_send_redirect(struct sk_buff *skb, struct neighbour *neigh,
1525			 const struct in6_addr *target)
1526{
1527	struct net_device *dev = skb->dev;
1528	struct net *net = dev_net(dev);
1529	struct sock *sk = net->ipv6.ndisc_sk;
1530	int len = sizeof(struct icmp6hdr) + 2 * sizeof(struct in6_addr);
1531	struct sk_buff *buff;
1532	struct icmp6hdr *icmph;
1533	struct in6_addr saddr_buf;
1534	struct in6_addr *addrp;
1535	struct rt6_info *rt;
1536	struct dst_entry *dst;
1537	struct inet6_dev *idev;
1538	struct flowi6 fl6;
1539	u8 *opt;
 
1540	int rd_len;
1541	int err;
1542	u8 ha_buf[MAX_ADDR_LEN], *ha = NULL;
1543
1544	if (ipv6_get_lladdr(dev, &saddr_buf, IFA_F_TENTATIVE)) {
1545		ND_PRINTK2(KERN_WARNING
1546			   "ICMPv6 Redirect: no link-local address on %s\n",
1547			   dev->name);
1548		return;
1549	}
1550
1551	if (!ipv6_addr_equal(&ipv6_hdr(skb)->daddr, target) &&
1552	    ipv6_addr_type(target) != (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
1553		ND_PRINTK2(KERN_WARNING
1554			"ICMPv6 Redirect: target address is not link-local unicast.\n");
1555		return;
1556	}
1557
1558	icmpv6_flow_init(sk, &fl6, NDISC_REDIRECT,
1559			 &saddr_buf, &ipv6_hdr(skb)->saddr, dev->ifindex);
1560
1561	dst = ip6_route_output(net, NULL, &fl6);
1562	if (dst == NULL)
 
1563		return;
1564
1565	dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), NULL, 0);
1566	if (IS_ERR(dst))
1567		return;
1568
1569	rt = (struct rt6_info *) dst;
1570
1571	if (rt->rt6i_flags & RTF_GATEWAY) {
1572		ND_PRINTK2(KERN_WARNING
1573			   "ICMPv6 Redirect: destination is not a neighbour.\n");
1574		goto release;
1575	}
1576	if (!rt->rt6i_peer)
1577		rt6_bind_peer(rt, 1);
1578	if (inet_peer_xrlim_allow(rt->rt6i_peer, 1*HZ))
1579		goto release;
1580
1581	if (dev->addr_len) {
 
 
 
 
 
 
 
1582		read_lock_bh(&neigh->lock);
1583		if (neigh->nud_state & NUD_VALID) {
1584			memcpy(ha_buf, neigh->ha, dev->addr_len);
1585			read_unlock_bh(&neigh->lock);
1586			ha = ha_buf;
1587			len += ndisc_opt_addr_space(dev);
1588		} else
1589			read_unlock_bh(&neigh->lock);
 
 
1590	}
1591
1592	rd_len = min_t(unsigned int,
1593		     IPV6_MIN_MTU-sizeof(struct ipv6hdr)-len, skb->len + 8);
1594	rd_len &= ~0x7;
1595	len += rd_len;
1596
 
 
1597	buff = sock_alloc_send_skb(sk,
1598				   (MAX_HEADER + sizeof(struct ipv6hdr) +
1599				    len + LL_ALLOCATED_SPACE(dev)),
1600				   1, &err);
1601	if (buff == NULL) {
1602		ND_PRINTK0(KERN_ERR
1603			   "ICMPv6 Redirect: %s() failed to allocate an skb, err=%d.\n",
1604			   __func__, err);
1605		goto release;
1606	}
1607
1608	skb_reserve(buff, LL_RESERVED_SPACE(dev));
1609	ip6_nd_hdr(sk, buff, dev, &saddr_buf, &ipv6_hdr(skb)->saddr,
1610		   IPPROTO_ICMPV6, len);
1611
1612	skb_set_transport_header(buff, skb_tail_pointer(buff) - buff->data);
1613	skb_put(buff, len);
1614	icmph = icmp6_hdr(buff);
1615
1616	memset(icmph, 0, sizeof(struct icmp6hdr));
1617	icmph->icmp6_type = NDISC_REDIRECT;
1618
1619	/*
1620	 *	copy target and destination addresses
1621	 */
1622
1623	addrp = (struct in6_addr *)(icmph + 1);
1624	ipv6_addr_copy(addrp, target);
1625	addrp++;
1626	ipv6_addr_copy(addrp, &ipv6_hdr(skb)->daddr);
1627
1628	opt = (u8*) (addrp + 1);
1629
1630	/*
1631	 *	include target_address option
1632	 */
1633
1634	if (ha)
1635		opt = ndisc_fill_addr_option(opt, ND_OPT_TARGET_LL_ADDR, ha,
1636					     dev->addr_len, dev->type);
1637
1638	/*
1639	 *	build redirect option and copy skb over to the new packet.
1640	 */
1641
1642	memset(opt, 0, 8);
1643	*(opt++) = ND_OPT_REDIRECT_HDR;
1644	*(opt++) = (rd_len >> 3);
1645	opt += 6;
1646
1647	memcpy(opt, ipv6_hdr(skb), rd_len - 8);
1648
1649	icmph->icmp6_cksum = csum_ipv6_magic(&saddr_buf, &ipv6_hdr(skb)->saddr,
1650					     len, IPPROTO_ICMPV6,
1651					     csum_partial(icmph, len, 0));
1652
1653	skb_dst_set(buff, dst);
1654	idev = in6_dev_get(dst->dev);
 
1655	IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUT, skb->len);
1656	err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT, buff, NULL, dst->dev,
1657		      dst_output);
1658	if (!err) {
1659		ICMP6MSGOUT_INC_STATS(net, idev, NDISC_REDIRECT);
1660		ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
1661	}
1662
1663	if (likely(idev != NULL))
1664		in6_dev_put(idev);
1665	return;
1666
1667release:
1668	dst_release(dst);
1669}
1670
1671static void pndisc_redo(struct sk_buff *skb)
1672{
1673	ndisc_recv_ns(skb);
1674	kfree_skb(skb);
1675}
1676
1677int ndisc_rcv(struct sk_buff *skb)
1678{
1679	struct nd_msg *msg;
1680
1681	if (!pskb_may_pull(skb, skb->len))
1682		return 0;
1683
1684	msg = (struct nd_msg *)skb_transport_header(skb);
1685
1686	__skb_push(skb, skb->data - skb_transport_header(skb));
1687
1688	if (ipv6_hdr(skb)->hop_limit != 255) {
1689		ND_PRINTK2(KERN_WARNING
1690			   "ICMPv6 NDISC: invalid hop-limit: %d\n",
1691			   ipv6_hdr(skb)->hop_limit);
1692		return 0;
1693	}
1694
1695	if (msg->icmph.icmp6_code != 0) {
1696		ND_PRINTK2(KERN_WARNING
1697			   "ICMPv6 NDISC: invalid ICMPv6 code: %d\n",
1698			   msg->icmph.icmp6_code);
1699		return 0;
1700	}
1701
1702	memset(NEIGH_CB(skb), 0, sizeof(struct neighbour_cb));
1703
1704	switch (msg->icmph.icmp6_type) {
1705	case NDISC_NEIGHBOUR_SOLICITATION:
1706		ndisc_recv_ns(skb);
1707		break;
1708
1709	case NDISC_NEIGHBOUR_ADVERTISEMENT:
1710		ndisc_recv_na(skb);
1711		break;
1712
1713	case NDISC_ROUTER_SOLICITATION:
1714		ndisc_recv_rs(skb);
1715		break;
1716
1717	case NDISC_ROUTER_ADVERTISEMENT:
1718		ndisc_router_discovery(skb);
1719		break;
1720
1721	case NDISC_REDIRECT:
1722		ndisc_redirect_rcv(skb);
1723		break;
1724	}
1725
1726	return 0;
1727}
1728
1729static int ndisc_netdev_event(struct notifier_block *this, unsigned long event, void *ptr)
1730{
1731	struct net_device *dev = ptr;
1732	struct net *net = dev_net(dev);
1733
1734	switch (event) {
1735	case NETDEV_CHANGEADDR:
1736		neigh_changeaddr(&nd_tbl, dev);
1737		fib6_run_gc(~0UL, net);
1738		break;
1739	case NETDEV_DOWN:
1740		neigh_ifdown(&nd_tbl, dev);
1741		fib6_run_gc(~0UL, net);
1742		break;
1743	case NETDEV_NOTIFY_PEERS:
1744		ndisc_send_unsol_na(dev);
1745		break;
1746	default:
1747		break;
1748	}
1749
1750	return NOTIFY_DONE;
1751}
1752
1753static struct notifier_block ndisc_netdev_notifier = {
1754	.notifier_call = ndisc_netdev_event,
1755};
1756
1757#ifdef CONFIG_SYSCTL
1758static void ndisc_warn_deprecated_sysctl(struct ctl_table *ctl,
1759					 const char *func, const char *dev_name)
1760{
1761	static char warncomm[TASK_COMM_LEN];
1762	static int warned;
1763	if (strcmp(warncomm, current->comm) && warned < 5) {
1764		strcpy(warncomm, current->comm);
1765		printk(KERN_WARNING
1766			"process `%s' is using deprecated sysctl (%s) "
1767			"net.ipv6.neigh.%s.%s; "
1768			"Use net.ipv6.neigh.%s.%s_ms "
1769			"instead.\n",
1770			warncomm, func,
1771			dev_name, ctl->procname,
1772			dev_name, ctl->procname);
1773		warned++;
1774	}
1775}
1776
1777int ndisc_ifinfo_sysctl_change(struct ctl_table *ctl, int write, void __user *buffer, size_t *lenp, loff_t *ppos)
1778{
1779	struct net_device *dev = ctl->extra1;
1780	struct inet6_dev *idev;
1781	int ret;
1782
1783	if ((strcmp(ctl->procname, "retrans_time") == 0) ||
1784	    (strcmp(ctl->procname, "base_reachable_time") == 0))
1785		ndisc_warn_deprecated_sysctl(ctl, "syscall", dev ? dev->name : "default");
1786
1787	if (strcmp(ctl->procname, "retrans_time") == 0)
1788		ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
1789
1790	else if (strcmp(ctl->procname, "base_reachable_time") == 0)
1791		ret = proc_dointvec_jiffies(ctl, write,
1792					    buffer, lenp, ppos);
1793
1794	else if ((strcmp(ctl->procname, "retrans_time_ms") == 0) ||
1795		 (strcmp(ctl->procname, "base_reachable_time_ms") == 0))
1796		ret = proc_dointvec_ms_jiffies(ctl, write,
1797					       buffer, lenp, ppos);
1798	else
1799		ret = -1;
1800
1801	if (write && ret == 0 && dev && (idev = in6_dev_get(dev)) != NULL) {
1802		if (ctl->data == &idev->nd_parms->base_reachable_time)
1803			idev->nd_parms->reachable_time = neigh_rand_reach_time(idev->nd_parms->base_reachable_time);
1804		idev->tstamp = jiffies;
1805		inet6_ifinfo_notify(RTM_NEWLINK, idev);
1806		in6_dev_put(idev);
1807	}
1808	return ret;
1809}
1810
1811
1812#endif
1813
1814static int __net_init ndisc_net_init(struct net *net)
1815{
1816	struct ipv6_pinfo *np;
1817	struct sock *sk;
1818	int err;
1819
1820	err = inet_ctl_sock_create(&sk, PF_INET6,
1821				   SOCK_RAW, IPPROTO_ICMPV6, net);
1822	if (err < 0) {
1823		ND_PRINTK0(KERN_ERR
1824			   "ICMPv6 NDISC: Failed to initialize the control socket (err %d).\n",
1825			   err);
1826		return err;
1827	}
1828
1829	net->ipv6.ndisc_sk = sk;
1830
1831	np = inet6_sk(sk);
1832	np->hop_limit = 255;
1833	/* Do not loopback ndisc messages */
1834	np->mc_loop = 0;
1835
1836	return 0;
1837}
1838
1839static void __net_exit ndisc_net_exit(struct net *net)
1840{
1841	inet_ctl_sock_destroy(net->ipv6.ndisc_sk);
1842}
1843
1844static struct pernet_operations ndisc_net_ops = {
1845	.init = ndisc_net_init,
1846	.exit = ndisc_net_exit,
1847};
1848
1849int __init ndisc_init(void)
1850{
1851	int err;
1852
1853	err = register_pernet_subsys(&ndisc_net_ops);
1854	if (err)
1855		return err;
1856	/*
1857	 * Initialize the neighbour table
1858	 */
1859	neigh_table_init(&nd_tbl);
1860
1861#ifdef CONFIG_SYSCTL
1862	err = neigh_sysctl_register(NULL, &nd_tbl.parms, "ipv6",
1863				    &ndisc_ifinfo_sysctl_change);
1864	if (err)
1865		goto out_unregister_pernet;
1866#endif
1867	err = register_netdevice_notifier(&ndisc_netdev_notifier);
1868	if (err)
1869		goto out_unregister_sysctl;
1870out:
1871	return err;
1872
1873out_unregister_sysctl:
1874#ifdef CONFIG_SYSCTL
1875	neigh_sysctl_unregister(&nd_tbl.parms);
1876out_unregister_pernet:
1877#endif
1878	unregister_pernet_subsys(&ndisc_net_ops);
1879	goto out;
1880}
1881
1882void ndisc_cleanup(void)
1883{
1884	unregister_netdevice_notifier(&ndisc_netdev_notifier);
1885#ifdef CONFIG_SYSCTL
1886	neigh_sysctl_unregister(&nd_tbl.parms);
1887#endif
1888	neigh_table_clear(&nd_tbl);
1889	unregister_pernet_subsys(&ndisc_net_ops);
1890}