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v3.1
   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}
v4.17
   1/*
   2 *	Neighbour Discovery for IPv6
   3 *	Linux INET6 implementation
   4 *
   5 *	Authors:
   6 *	Pedro Roque		<roque@di.fc.ul.pt>
   7 *	Mike Shaver		<shaver@ingenia.com>
   8 *
   9 *	This program is free software; you can redistribute it and/or
  10 *      modify it under the terms of the GNU General Public License
  11 *      as published by the Free Software Foundation; either version
  12 *      2 of the License, or (at your option) any later version.
  13 */
  14
  15/*
  16 *	Changes:
  17 *
  18 *	Alexey I. Froloff		:	RFC6106 (DNSSL) support
  19 *	Pierre Ynard			:	export userland ND options
  20 *						through netlink (RDNSS support)
  21 *	Lars Fenneberg			:	fixed MTU setting on receipt
  22 *						of an RA.
  23 *	Janos Farkas			:	kmalloc failure checks
  24 *	Alexey Kuznetsov		:	state machine reworked
  25 *						and moved to net/core.
  26 *	Pekka Savola			:	RFC2461 validation
  27 *	YOSHIFUJI Hideaki @USAGI	:	Verify ND options properly
  28 */
  29
  30#define pr_fmt(fmt) "ICMPv6: " fmt
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  31
  32#include <linux/module.h>
  33#include <linux/errno.h>
  34#include <linux/types.h>
  35#include <linux/socket.h>
  36#include <linux/sockios.h>
  37#include <linux/sched.h>
  38#include <linux/net.h>
  39#include <linux/in6.h>
  40#include <linux/route.h>
  41#include <linux/init.h>
  42#include <linux/rcupdate.h>
  43#include <linux/slab.h>
  44#ifdef CONFIG_SYSCTL
  45#include <linux/sysctl.h>
  46#endif
  47
  48#include <linux/if_addr.h>
  49#include <linux/if_ether.h>
  50#include <linux/if_arp.h>
  51#include <linux/ipv6.h>
  52#include <linux/icmpv6.h>
  53#include <linux/jhash.h>
  54
  55#include <net/sock.h>
  56#include <net/snmp.h>
  57
  58#include <net/ipv6.h>
  59#include <net/protocol.h>
  60#include <net/ndisc.h>
  61#include <net/ip6_route.h>
  62#include <net/addrconf.h>
  63#include <net/icmp.h>
  64
  65#include <net/netlink.h>
  66#include <linux/rtnetlink.h>
  67
  68#include <net/flow.h>
  69#include <net/ip6_checksum.h>
  70#include <net/inet_common.h>
  71#include <linux/proc_fs.h>
  72
  73#include <linux/netfilter.h>
  74#include <linux/netfilter_ipv6.h>
  75
  76static u32 ndisc_hash(const void *pkey,
  77		      const struct net_device *dev,
  78		      __u32 *hash_rnd);
  79static bool ndisc_key_eq(const struct neighbour *neigh, const void *pkey);
  80static int ndisc_constructor(struct neighbour *neigh);
  81static void ndisc_solicit(struct neighbour *neigh, struct sk_buff *skb);
  82static void ndisc_error_report(struct neighbour *neigh, struct sk_buff *skb);
  83static int pndisc_constructor(struct pneigh_entry *n);
  84static void pndisc_destructor(struct pneigh_entry *n);
  85static void pndisc_redo(struct sk_buff *skb);
  86
  87static const struct neigh_ops ndisc_generic_ops = {
  88	.family =		AF_INET6,
  89	.solicit =		ndisc_solicit,
  90	.error_report =		ndisc_error_report,
  91	.output =		neigh_resolve_output,
  92	.connected_output =	neigh_connected_output,
  93};
  94
  95static const struct neigh_ops ndisc_hh_ops = {
  96	.family =		AF_INET6,
  97	.solicit =		ndisc_solicit,
  98	.error_report =		ndisc_error_report,
  99	.output =		neigh_resolve_output,
 100	.connected_output =	neigh_resolve_output,
 101};
 102
 103
 104static const struct neigh_ops ndisc_direct_ops = {
 105	.family =		AF_INET6,
 106	.output =		neigh_direct_output,
 107	.connected_output =	neigh_direct_output,
 108};
 109
 110struct neigh_table nd_tbl = {
 111	.family =	AF_INET6,
 
 112	.key_len =	sizeof(struct in6_addr),
 113	.protocol =	cpu_to_be16(ETH_P_IPV6),
 114	.hash =		ndisc_hash,
 115	.key_eq =	ndisc_key_eq,
 116	.constructor =	ndisc_constructor,
 117	.pconstructor =	pndisc_constructor,
 118	.pdestructor =	pndisc_destructor,
 119	.proxy_redo =	pndisc_redo,
 120	.id =		"ndisc_cache",
 121	.parms = {
 122		.tbl			= &nd_tbl,
 
 
 
 123		.reachable_time		= ND_REACHABLE_TIME,
 124		.data = {
 125			[NEIGH_VAR_MCAST_PROBES] = 3,
 126			[NEIGH_VAR_UCAST_PROBES] = 3,
 127			[NEIGH_VAR_RETRANS_TIME] = ND_RETRANS_TIMER,
 128			[NEIGH_VAR_BASE_REACHABLE_TIME] = ND_REACHABLE_TIME,
 129			[NEIGH_VAR_DELAY_PROBE_TIME] = 5 * HZ,
 130			[NEIGH_VAR_GC_STALETIME] = 60 * HZ,
 131			[NEIGH_VAR_QUEUE_LEN_BYTES] = SK_WMEM_MAX,
 132			[NEIGH_VAR_PROXY_QLEN] = 64,
 133			[NEIGH_VAR_ANYCAST_DELAY] = 1 * HZ,
 134			[NEIGH_VAR_PROXY_DELAY] = (8 * HZ) / 10,
 135		},
 136	},
 137	.gc_interval =	  30 * HZ,
 138	.gc_thresh1 =	 128,
 139	.gc_thresh2 =	 512,
 140	.gc_thresh3 =	1024,
 141};
 142EXPORT_SYMBOL_GPL(nd_tbl);
 143
 144void __ndisc_fill_addr_option(struct sk_buff *skb, int type, void *data,
 145			      int data_len, int pad)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 146{
 147	int space = __ndisc_opt_addr_space(data_len, pad);
 148	u8 *opt = skb_put(skb, space);
 149
 150	opt[0] = type;
 151	opt[1] = space>>3;
 152
 153	memset(opt + 2, 0, pad);
 154	opt   += pad;
 155	space -= pad;
 156
 157	memcpy(opt+2, data, data_len);
 158	data_len += 2;
 159	opt += data_len;
 160	space -= data_len;
 161	if (space > 0)
 162		memset(opt, 0, space);
 163}
 164EXPORT_SYMBOL_GPL(__ndisc_fill_addr_option);
 165
 166static inline void ndisc_fill_addr_option(struct sk_buff *skb, int type,
 167					  void *data, u8 icmp6_type)
 168{
 169	__ndisc_fill_addr_option(skb, type, data, skb->dev->addr_len,
 170				 ndisc_addr_option_pad(skb->dev->type));
 171	ndisc_ops_fill_addr_option(skb->dev, skb, icmp6_type);
 172}
 173
 174static inline void ndisc_fill_redirect_addr_option(struct sk_buff *skb,
 175						   void *ha,
 176						   const u8 *ops_data)
 177{
 178	ndisc_fill_addr_option(skb, ND_OPT_TARGET_LL_ADDR, ha, NDISC_REDIRECT);
 179	ndisc_ops_fill_redirect_addr_option(skb->dev, skb, ops_data);
 180}
 181
 182static struct nd_opt_hdr *ndisc_next_option(struct nd_opt_hdr *cur,
 183					    struct nd_opt_hdr *end)
 184{
 185	int type;
 186	if (!cur || !end || cur >= end)
 187		return NULL;
 188	type = cur->nd_opt_type;
 189	do {
 190		cur = ((void *)cur) + (cur->nd_opt_len << 3);
 191	} while (cur < end && cur->nd_opt_type != type);
 192	return cur <= end && cur->nd_opt_type == type ? cur : NULL;
 193}
 194
 195static inline int ndisc_is_useropt(const struct net_device *dev,
 196				   struct nd_opt_hdr *opt)
 197{
 198	return opt->nd_opt_type == ND_OPT_RDNSS ||
 199		opt->nd_opt_type == ND_OPT_DNSSL ||
 200		ndisc_ops_is_useropt(dev, opt->nd_opt_type);
 201}
 202
 203static struct nd_opt_hdr *ndisc_next_useropt(const struct net_device *dev,
 204					     struct nd_opt_hdr *cur,
 205					     struct nd_opt_hdr *end)
 206{
 207	if (!cur || !end || cur >= end)
 208		return NULL;
 209	do {
 210		cur = ((void *)cur) + (cur->nd_opt_len << 3);
 211	} while (cur < end && !ndisc_is_useropt(dev, cur));
 212	return cur <= end && ndisc_is_useropt(dev, cur) ? cur : NULL;
 213}
 214
 215struct ndisc_options *ndisc_parse_options(const struct net_device *dev,
 216					  u8 *opt, int opt_len,
 217					  struct ndisc_options *ndopts)
 218{
 219	struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)opt;
 220
 221	if (!nd_opt || opt_len < 0 || !ndopts)
 222		return NULL;
 223	memset(ndopts, 0, sizeof(*ndopts));
 224	while (opt_len) {
 225		int l;
 226		if (opt_len < sizeof(struct nd_opt_hdr))
 227			return NULL;
 228		l = nd_opt->nd_opt_len << 3;
 229		if (opt_len < l || l == 0)
 230			return NULL;
 231		if (ndisc_ops_parse_options(dev, nd_opt, ndopts))
 232			goto next_opt;
 233		switch (nd_opt->nd_opt_type) {
 234		case ND_OPT_SOURCE_LL_ADDR:
 235		case ND_OPT_TARGET_LL_ADDR:
 236		case ND_OPT_MTU:
 237		case ND_OPT_NONCE:
 238		case ND_OPT_REDIRECT_HDR:
 239			if (ndopts->nd_opt_array[nd_opt->nd_opt_type]) {
 240				ND_PRINTK(2, warn,
 241					  "%s: duplicated ND6 option found: type=%d\n",
 242					  __func__, nd_opt->nd_opt_type);
 
 243			} else {
 244				ndopts->nd_opt_array[nd_opt->nd_opt_type] = nd_opt;
 245			}
 246			break;
 247		case ND_OPT_PREFIX_INFO:
 248			ndopts->nd_opts_pi_end = nd_opt;
 249			if (!ndopts->nd_opt_array[nd_opt->nd_opt_type])
 250				ndopts->nd_opt_array[nd_opt->nd_opt_type] = nd_opt;
 251			break;
 252#ifdef CONFIG_IPV6_ROUTE_INFO
 253		case ND_OPT_ROUTE_INFO:
 254			ndopts->nd_opts_ri_end = nd_opt;
 255			if (!ndopts->nd_opts_ri)
 256				ndopts->nd_opts_ri = nd_opt;
 257			break;
 258#endif
 259		default:
 260			if (ndisc_is_useropt(dev, nd_opt)) {
 261				ndopts->nd_useropts_end = nd_opt;
 262				if (!ndopts->nd_useropts)
 263					ndopts->nd_useropts = nd_opt;
 264			} else {
 265				/*
 266				 * Unknown options must be silently ignored,
 267				 * to accommodate future extension to the
 268				 * protocol.
 269				 */
 270				ND_PRINTK(2, notice,
 271					  "%s: ignored unsupported option; type=%d, len=%d\n",
 272					  __func__,
 273					  nd_opt->nd_opt_type,
 274					  nd_opt->nd_opt_len);
 275			}
 276		}
 277next_opt:
 278		opt_len -= l;
 279		nd_opt = ((void *)nd_opt) + l;
 280	}
 281	return ndopts;
 282}
 283
 
 
 
 
 
 
 
 
 
 
 
 284int ndisc_mc_map(const struct in6_addr *addr, char *buf, struct net_device *dev, int dir)
 285{
 286	switch (dev->type) {
 287	case ARPHRD_ETHER:
 288	case ARPHRD_IEEE802:	/* Not sure. Check it later. --ANK */
 289	case ARPHRD_FDDI:
 290		ipv6_eth_mc_map(addr, buf);
 291		return 0;
 
 
 
 292	case ARPHRD_ARCNET:
 293		ipv6_arcnet_mc_map(addr, buf);
 294		return 0;
 295	case ARPHRD_INFINIBAND:
 296		ipv6_ib_mc_map(addr, dev->broadcast, buf);
 297		return 0;
 298	case ARPHRD_IPGRE:
 299		return ipv6_ipgre_mc_map(addr, dev->broadcast, buf);
 300	default:
 301		if (dir) {
 302			memcpy(buf, dev->broadcast, dev->addr_len);
 303			return 0;
 304		}
 305	}
 306	return -EINVAL;
 307}
 
 308EXPORT_SYMBOL(ndisc_mc_map);
 309
 310static u32 ndisc_hash(const void *pkey,
 311		      const struct net_device *dev,
 312		      __u32 *hash_rnd)
 313{
 314	return ndisc_hashfn(pkey, dev, hash_rnd);
 315}
 
 
 
 
 316
 317static bool ndisc_key_eq(const struct neighbour *n, const void *pkey)
 318{
 319	return neigh_key_eq128(n, pkey);
 320}
 321
 322static int ndisc_constructor(struct neighbour *neigh)
 323{
 324	struct in6_addr *addr = (struct in6_addr *)&neigh->primary_key;
 325	struct net_device *dev = neigh->dev;
 326	struct inet6_dev *in6_dev;
 327	struct neigh_parms *parms;
 328	bool is_multicast = ipv6_addr_is_multicast(addr);
 329
 
 330	in6_dev = in6_dev_get(dev);
 331	if (!in6_dev) {
 
 332		return -EINVAL;
 333	}
 334
 335	parms = in6_dev->nd_parms;
 336	__neigh_parms_put(neigh->parms);
 337	neigh->parms = neigh_parms_clone(parms);
 
 338
 339	neigh->type = is_multicast ? RTN_MULTICAST : RTN_UNICAST;
 340	if (!dev->header_ops) {
 341		neigh->nud_state = NUD_NOARP;
 342		neigh->ops = &ndisc_direct_ops;
 343		neigh->output = neigh_direct_output;
 344	} else {
 345		if (is_multicast) {
 346			neigh->nud_state = NUD_NOARP;
 347			ndisc_mc_map(addr, neigh->ha, dev, 1);
 348		} else if (dev->flags&(IFF_NOARP|IFF_LOOPBACK)) {
 349			neigh->nud_state = NUD_NOARP;
 350			memcpy(neigh->ha, dev->dev_addr, dev->addr_len);
 351			if (dev->flags&IFF_LOOPBACK)
 352				neigh->type = RTN_LOCAL;
 353		} else if (dev->flags&IFF_POINTOPOINT) {
 354			neigh->nud_state = NUD_NOARP;
 355			memcpy(neigh->ha, dev->broadcast, dev->addr_len);
 356		}
 357		if (dev->header_ops->cache)
 358			neigh->ops = &ndisc_hh_ops;
 359		else
 360			neigh->ops = &ndisc_generic_ops;
 361		if (neigh->nud_state&NUD_VALID)
 362			neigh->output = neigh->ops->connected_output;
 363		else
 364			neigh->output = neigh->ops->output;
 365	}
 366	in6_dev_put(in6_dev);
 367	return 0;
 368}
 369
 370static int pndisc_constructor(struct pneigh_entry *n)
 371{
 372	struct in6_addr *addr = (struct in6_addr *)&n->key;
 373	struct in6_addr maddr;
 374	struct net_device *dev = n->dev;
 375
 376	if (!dev || !__in6_dev_get(dev))
 377		return -EINVAL;
 378	addrconf_addr_solict_mult(addr, &maddr);
 379	ipv6_dev_mc_inc(dev, &maddr);
 380	return 0;
 381}
 382
 383static void pndisc_destructor(struct pneigh_entry *n)
 384{
 385	struct in6_addr *addr = (struct in6_addr *)&n->key;
 386	struct in6_addr maddr;
 387	struct net_device *dev = n->dev;
 388
 389	if (!dev || !__in6_dev_get(dev))
 390		return;
 391	addrconf_addr_solict_mult(addr, &maddr);
 392	ipv6_dev_mc_dec(dev, &maddr);
 393}
 394
 395static struct sk_buff *ndisc_alloc_skb(struct net_device *dev,
 396				       int len)
 
 
 
 
 397{
 398	int hlen = LL_RESERVED_SPACE(dev);
 399	int tlen = dev->needed_tailroom;
 400	struct sock *sk = dev_net(dev)->ipv6.ndisc_sk;
 401	struct sk_buff *skb;
 
 
 
 
 402
 403	skb = alloc_skb(hlen + sizeof(struct ipv6hdr) + len + tlen, GFP_ATOMIC);
 
 
 
 
 
 
 
 
 
 
 404	if (!skb) {
 405		ND_PRINTK(0, err, "ndisc: %s failed to allocate an skb\n",
 406			  __func__);
 
 407		return NULL;
 408	}
 409
 410	skb->protocol = htons(ETH_P_IPV6);
 411	skb->dev = dev;
 412
 413	skb_reserve(skb, hlen + sizeof(struct ipv6hdr));
 414	skb_reset_transport_header(skb);
 415
 416	/* Manually assign socket ownership as we avoid calling
 417	 * sock_alloc_send_pskb() to bypass wmem buffer limits
 418	 */
 419	skb_set_owner_w(skb, sk);
 420
 421	return skb;
 422}
 
 
 
 423
 424static void ip6_nd_hdr(struct sk_buff *skb,
 425		       const struct in6_addr *saddr,
 426		       const struct in6_addr *daddr,
 427		       int hop_limit, int len)
 428{
 429	struct ipv6hdr *hdr;
 430	struct inet6_dev *idev;
 431	unsigned tclass;
 432
 433	rcu_read_lock();
 434	idev = __in6_dev_get(skb->dev);
 435	tclass = idev ? idev->cnf.ndisc_tclass : 0;
 436	rcu_read_unlock();
 437
 438	skb_push(skb, sizeof(*hdr));
 439	skb_reset_network_header(skb);
 440	hdr = ipv6_hdr(skb);
 441
 442	ip6_flow_hdr(hdr, tclass, 0);
 443
 444	hdr->payload_len = htons(len);
 445	hdr->nexthdr = IPPROTO_ICMPV6;
 446	hdr->hop_limit = hop_limit;
 447
 448	hdr->saddr = *saddr;
 449	hdr->daddr = *daddr;
 450}
 451
 452static void ndisc_send_skb(struct sk_buff *skb,
 453			   const struct in6_addr *daddr,
 454			   const struct in6_addr *saddr)
 455{
 456	struct dst_entry *dst = skb_dst(skb);
 457	struct net *net = dev_net(skb->dev);
 
 458	struct sock *sk = net->ipv6.ndisc_sk;
 459	struct inet6_dev *idev;
 460	int err;
 461	struct icmp6hdr *icmp6h = icmp6_hdr(skb);
 462	u8 type;
 463
 464	type = icmp6h->icmp6_type;
 465
 
 
 
 466	if (!dst) {
 467		struct flowi6 fl6;
 468		int oif = skb->dev->ifindex;
 
 469
 470		icmpv6_flow_init(sk, &fl6, type, saddr, daddr, oif);
 471		dst = icmp6_dst_alloc(skb->dev, &fl6);
 472		if (IS_ERR(dst)) {
 473			kfree_skb(skb);
 474			return;
 475		}
 476
 477		skb_dst_set(skb, dst);
 478	}
 479
 480	icmp6h->icmp6_cksum = csum_ipv6_magic(saddr, daddr, skb->len,
 481					      IPPROTO_ICMPV6,
 482					      csum_partial(icmp6h,
 483							   skb->len, 0));
 484
 485	ip6_nd_hdr(skb, saddr, daddr, inet6_sk(sk)->hop_limit, skb->len);
 486
 487	rcu_read_lock();
 488	idev = __in6_dev_get(dst->dev);
 489	IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUT, skb->len);
 490
 491	err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT,
 492		      net, sk, skb, NULL, dst->dev,
 493		      dst_output);
 494	if (!err) {
 495		ICMP6MSGOUT_INC_STATS(net, idev, type);
 496		ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
 497	}
 498
 499	rcu_read_unlock();
 
 500}
 501
 502void ndisc_send_na(struct net_device *dev, const struct in6_addr *daddr,
 503		   const struct in6_addr *solicited_addr,
 504		   bool router, bool solicited, bool override, bool inc_opt)
 
 
 
 
 
 
 
 
 505{
 506	struct sk_buff *skb;
 
 
 
 
 
 
 
 
 
 
 
 
 
 507	struct in6_addr tmpaddr;
 508	struct inet6_ifaddr *ifp;
 509	const struct in6_addr *src_addr;
 510	struct nd_msg *msg;
 511	int optlen = 0;
 
 512
 513	/* for anycast or proxy, solicited_addr != src_addr */
 514	ifp = ipv6_get_ifaddr(dev_net(dev), solicited_addr, dev, 1);
 515	if (ifp) {
 516		src_addr = solicited_addr;
 517		if (ifp->flags & IFA_F_OPTIMISTIC)
 518			override = false;
 519		inc_opt |= ifp->idev->cnf.force_tllao;
 520		in6_ifa_put(ifp);
 521	} else {
 522		if (ipv6_dev_get_saddr(dev_net(dev), dev, daddr,
 523				       inet6_sk(dev_net(dev)->ipv6.ndisc_sk)->srcprefs,
 524				       &tmpaddr))
 525			return;
 526		src_addr = &tmpaddr;
 527	}
 528
 529	if (!dev->addr_len)
 530		inc_opt = false;
 531	if (inc_opt)
 532		optlen += ndisc_opt_addr_space(dev,
 533					       NDISC_NEIGHBOUR_ADVERTISEMENT);
 534
 535	skb = ndisc_alloc_skb(dev, sizeof(*msg) + optlen);
 536	if (!skb)
 537		return;
 538
 539	msg = skb_put(skb, sizeof(*msg));
 540	*msg = (struct nd_msg) {
 541		.icmph = {
 542			.icmp6_type = NDISC_NEIGHBOUR_ADVERTISEMENT,
 543			.icmp6_router = router,
 544			.icmp6_solicited = solicited,
 545			.icmp6_override = override,
 546		},
 547		.target = *solicited_addr,
 548	};
 549
 550	if (inc_opt)
 551		ndisc_fill_addr_option(skb, ND_OPT_TARGET_LL_ADDR,
 552				       dev->dev_addr,
 553				       NDISC_NEIGHBOUR_ADVERTISEMENT);
 554
 555	ndisc_send_skb(skb, daddr, src_addr);
 556}
 557
 558static void ndisc_send_unsol_na(struct net_device *dev)
 559{
 560	struct inet6_dev *idev;
 561	struct inet6_ifaddr *ifa;
 
 562
 563	idev = in6_dev_get(dev);
 564	if (!idev)
 565		return;
 566
 567	read_lock_bh(&idev->lock);
 568	list_for_each_entry(ifa, &idev->addr_list, if_list) {
 569		/* skip tentative addresses until dad completes */
 570		if (ifa->flags & IFA_F_TENTATIVE &&
 571		    !(ifa->flags & IFA_F_OPTIMISTIC))
 572			continue;
 573
 574		ndisc_send_na(dev, &in6addr_linklocal_allnodes, &ifa->addr,
 575			      /*router=*/ !!idev->cnf.forwarding,
 576			      /*solicited=*/ false, /*override=*/ true,
 577			      /*inc_opt=*/ true);
 578	}
 579	read_unlock_bh(&idev->lock);
 580
 581	in6_dev_put(idev);
 582}
 583
 584void ndisc_send_ns(struct net_device *dev, const struct in6_addr *solicit,
 585		   const struct in6_addr *daddr, const struct in6_addr *saddr,
 586		   u64 nonce)
 587{
 588	struct sk_buff *skb;
 589	struct in6_addr addr_buf;
 590	int inc_opt = dev->addr_len;
 591	int optlen = 0;
 592	struct nd_msg *msg;
 593
 594	if (!saddr) {
 595		if (ipv6_get_lladdr(dev, &addr_buf,
 596				   (IFA_F_TENTATIVE|IFA_F_OPTIMISTIC)))
 597			return;
 598		saddr = &addr_buf;
 599	}
 600
 601	if (ipv6_addr_any(saddr))
 602		inc_opt = false;
 603	if (inc_opt)
 604		optlen += ndisc_opt_addr_space(dev,
 605					       NDISC_NEIGHBOUR_SOLICITATION);
 606	if (nonce != 0)
 607		optlen += 8;
 608
 609	skb = ndisc_alloc_skb(dev, sizeof(*msg) + optlen);
 610	if (!skb)
 611		return;
 612
 613	msg = skb_put(skb, sizeof(*msg));
 614	*msg = (struct nd_msg) {
 615		.icmph = {
 616			.icmp6_type = NDISC_NEIGHBOUR_SOLICITATION,
 617		},
 618		.target = *solicit,
 619	};
 620
 621	if (inc_opt)
 622		ndisc_fill_addr_option(skb, ND_OPT_SOURCE_LL_ADDR,
 623				       dev->dev_addr,
 624				       NDISC_NEIGHBOUR_SOLICITATION);
 625	if (nonce != 0) {
 626		u8 *opt = skb_put(skb, 8);
 627
 628		opt[0] = ND_OPT_NONCE;
 629		opt[1] = 8 >> 3;
 630		memcpy(opt + 2, &nonce, 6);
 631	}
 632
 633	ndisc_send_skb(skb, daddr, saddr);
 634}
 635
 636void ndisc_send_rs(struct net_device *dev, const struct in6_addr *saddr,
 637		   const struct in6_addr *daddr)
 638{
 639	struct sk_buff *skb;
 640	struct rs_msg *msg;
 
 641	int send_sllao = dev->addr_len;
 642	int optlen = 0;
 643
 644#ifdef CONFIG_IPV6_OPTIMISTIC_DAD
 645	/*
 646	 * According to section 2.2 of RFC 4429, we must not
 647	 * send router solicitations with a sllao from
 648	 * optimistic addresses, but we may send the solicitation
 649	 * if we don't include the sllao.  So here we check
 650	 * if our address is optimistic, and if so, we
 651	 * suppress the inclusion of the sllao.
 652	 */
 653	if (send_sllao) {
 654		struct inet6_ifaddr *ifp = ipv6_get_ifaddr(dev_net(dev), saddr,
 655							   dev, 1);
 656		if (ifp) {
 657			if (ifp->flags & IFA_F_OPTIMISTIC)  {
 658				send_sllao = 0;
 659			}
 660			in6_ifa_put(ifp);
 661		} else {
 662			send_sllao = 0;
 663		}
 664	}
 665#endif
 666	if (send_sllao)
 667		optlen += ndisc_opt_addr_space(dev, NDISC_ROUTER_SOLICITATION);
 668
 669	skb = ndisc_alloc_skb(dev, sizeof(*msg) + optlen);
 670	if (!skb)
 671		return;
 672
 673	msg = skb_put(skb, sizeof(*msg));
 674	*msg = (struct rs_msg) {
 675		.icmph = {
 676			.icmp6_type = NDISC_ROUTER_SOLICITATION,
 677		},
 678	};
 679
 680	if (send_sllao)
 681		ndisc_fill_addr_option(skb, ND_OPT_SOURCE_LL_ADDR,
 682				       dev->dev_addr,
 683				       NDISC_ROUTER_SOLICITATION);
 684
 685	ndisc_send_skb(skb, daddr, saddr);
 686}
 687
 688
 689static void ndisc_error_report(struct neighbour *neigh, struct sk_buff *skb)
 690{
 691	/*
 692	 *	"The sender MUST return an ICMP
 693	 *	 destination unreachable"
 694	 */
 695	dst_link_failure(skb);
 696	kfree_skb(skb);
 697}
 698
 699/* Called with locked neigh: either read or both */
 700
 701static void ndisc_solicit(struct neighbour *neigh, struct sk_buff *skb)
 702{
 703	struct in6_addr *saddr = NULL;
 704	struct in6_addr mcaddr;
 705	struct net_device *dev = neigh->dev;
 706	struct in6_addr *target = (struct in6_addr *)&neigh->primary_key;
 707	int probes = atomic_read(&neigh->probes);
 708
 709	if (skb && ipv6_chk_addr_and_flags(dev_net(dev), &ipv6_hdr(skb)->saddr,
 710					   dev, false, 1,
 711					   IFA_F_TENTATIVE|IFA_F_OPTIMISTIC))
 712		saddr = &ipv6_hdr(skb)->saddr;
 713	probes -= NEIGH_VAR(neigh->parms, UCAST_PROBES);
 714	if (probes < 0) {
 715		if (!(neigh->nud_state & NUD_VALID)) {
 716			ND_PRINTK(1, dbg,
 717				  "%s: trying to ucast probe in NUD_INVALID: %pI6\n",
 718				  __func__, target);
 719		}
 720		ndisc_send_ns(dev, target, target, saddr, 0);
 721	} else if ((probes -= NEIGH_VAR(neigh->parms, APP_PROBES)) < 0) {
 
 722		neigh_app_ns(neigh);
 
 723	} else {
 724		addrconf_addr_solict_mult(target, &mcaddr);
 725		ndisc_send_ns(dev, target, &mcaddr, saddr, 0);
 726	}
 727}
 728
 729static int pndisc_is_router(const void *pkey,
 730			    struct net_device *dev)
 731{
 732	struct pneigh_entry *n;
 733	int ret = -1;
 734
 735	read_lock_bh(&nd_tbl.lock);
 736	n = __pneigh_lookup(&nd_tbl, dev_net(dev), pkey, dev);
 737	if (n)
 738		ret = !!(n->flags & NTF_ROUTER);
 739	read_unlock_bh(&nd_tbl.lock);
 740
 741	return ret;
 742}
 743
 744void ndisc_update(const struct net_device *dev, struct neighbour *neigh,
 745		  const u8 *lladdr, u8 new, u32 flags, u8 icmp6_type,
 746		  struct ndisc_options *ndopts)
 747{
 748	neigh_update(neigh, lladdr, new, flags, 0);
 749	/* report ndisc ops about neighbour update */
 750	ndisc_ops_update(dev, neigh, flags, icmp6_type, ndopts);
 751}
 752
 753static void ndisc_recv_ns(struct sk_buff *skb)
 754{
 755	struct nd_msg *msg = (struct nd_msg *)skb_transport_header(skb);
 756	const struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
 757	const struct in6_addr *daddr = &ipv6_hdr(skb)->daddr;
 758	u8 *lladdr = NULL;
 759	u32 ndoptlen = skb_tail_pointer(skb) - (skb_transport_header(skb) +
 760				    offsetof(struct nd_msg, opt));
 761	struct ndisc_options ndopts;
 762	struct net_device *dev = skb->dev;
 763	struct inet6_ifaddr *ifp;
 764	struct inet6_dev *idev = NULL;
 765	struct neighbour *neigh;
 766	int dad = ipv6_addr_any(saddr);
 767	bool inc;
 768	int is_router = -1;
 769	u64 nonce = 0;
 770
 771	if (skb->len < sizeof(struct nd_msg)) {
 772		ND_PRINTK(2, warn, "NS: packet too short\n");
 773		return;
 774	}
 775
 776	if (ipv6_addr_is_multicast(&msg->target)) {
 777		ND_PRINTK(2, warn, "NS: multicast target address\n");
 
 778		return;
 779	}
 780
 781	/*
 782	 * RFC2461 7.1.1:
 783	 * DAD has to be destined for solicited node multicast address.
 784	 */
 785	if (dad && !ipv6_addr_is_solict_mult(daddr)) {
 786		ND_PRINTK(2, warn, "NS: bad DAD packet (wrong destination)\n");
 
 
 
 
 
 787		return;
 788	}
 789
 790	if (!ndisc_parse_options(dev, msg->opt, ndoptlen, &ndopts)) {
 791		ND_PRINTK(2, warn, "NS: invalid ND options\n");
 
 792		return;
 793	}
 794
 795	if (ndopts.nd_opts_src_lladdr) {
 796		lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr, dev);
 797		if (!lladdr) {
 798			ND_PRINTK(2, warn,
 799				  "NS: invalid link-layer address length\n");
 800			return;
 801		}
 802
 803		/* RFC2461 7.1.1:
 804		 *	If the IP source address is the unspecified address,
 805		 *	there MUST NOT be source link-layer address option
 806		 *	in the message.
 807		 */
 808		if (dad) {
 809			ND_PRINTK(2, warn,
 810				  "NS: bad DAD packet (link-layer address option)\n");
 811			return;
 812		}
 813	}
 814	if (ndopts.nd_opts_nonce)
 815		memcpy(&nonce, (u8 *)(ndopts.nd_opts_nonce + 1), 6);
 816
 817	inc = ipv6_addr_is_multicast(daddr);
 818
 819	ifp = ipv6_get_ifaddr(dev_net(dev), &msg->target, dev, 1);
 820	if (ifp) {
 821have_ifp:
 822		if (ifp->flags & (IFA_F_TENTATIVE|IFA_F_OPTIMISTIC)) {
 823			if (dad) {
 824				if (nonce != 0 && ifp->dad_nonce == nonce) {
 825					u8 *np = (u8 *)&nonce;
 826					/* Matching nonce if looped back */
 827					ND_PRINTK(2, notice,
 828						  "%s: IPv6 DAD loopback for address %pI6c nonce %pM ignored\n",
 829						  ifp->idev->dev->name,
 830						  &ifp->addr, np);
 831					goto out;
 
 
 
 
 832				}
 
 833				/*
 834				 * We are colliding with another node
 835				 * who is doing DAD
 836				 * so fail our DAD process
 837				 */
 838				addrconf_dad_failure(skb, ifp);
 839				return;
 840			} else {
 841				/*
 842				 * This is not a dad solicitation.
 843				 * If we are an optimistic node,
 844				 * we should respond.
 845				 * Otherwise, we should ignore it.
 846				 */
 847				if (!(ifp->flags & IFA_F_OPTIMISTIC))
 848					goto out;
 849			}
 850		}
 851
 852		idev = ifp->idev;
 853	} else {
 854		struct net *net = dev_net(dev);
 855
 856		/* perhaps an address on the master device */
 857		if (netif_is_l3_slave(dev)) {
 858			struct net_device *mdev;
 859
 860			mdev = netdev_master_upper_dev_get_rcu(dev);
 861			if (mdev) {
 862				ifp = ipv6_get_ifaddr(net, &msg->target, mdev, 1);
 863				if (ifp)
 864					goto have_ifp;
 865			}
 866		}
 867
 868		idev = in6_dev_get(dev);
 869		if (!idev) {
 870			/* XXX: count this drop? */
 871			return;
 872		}
 873
 874		if (ipv6_chk_acast_addr(net, dev, &msg->target) ||
 875		    (idev->cnf.forwarding &&
 876		     (net->ipv6.devconf_all->proxy_ndp || idev->cnf.proxy_ndp) &&
 877		     (is_router = pndisc_is_router(&msg->target, dev)) >= 0)) {
 878			if (!(NEIGH_CB(skb)->flags & LOCALLY_ENQUEUED) &&
 879			    skb->pkt_type != PACKET_HOST &&
 880			    inc &&
 881			    NEIGH_VAR(idev->nd_parms, PROXY_DELAY) != 0) {
 882				/*
 883				 * for anycast or proxy,
 884				 * sender should delay its response
 885				 * by a random time between 0 and
 886				 * MAX_ANYCAST_DELAY_TIME seconds.
 887				 * (RFC2461) -- yoshfuji
 888				 */
 889				struct sk_buff *n = skb_clone(skb, GFP_ATOMIC);
 890				if (n)
 891					pneigh_enqueue(&nd_tbl, idev->nd_parms, n);
 892				goto out;
 893			}
 894		} else
 895			goto out;
 896	}
 897
 898	if (is_router < 0)
 899		is_router = idev->cnf.forwarding;
 900
 901	if (dad) {
 902		ndisc_send_na(dev, &in6addr_linklocal_allnodes, &msg->target,
 903			      !!is_router, false, (ifp != NULL), true);
 904		goto out;
 905	}
 906
 907	if (inc)
 908		NEIGH_CACHE_STAT_INC(&nd_tbl, rcv_probes_mcast);
 909	else
 910		NEIGH_CACHE_STAT_INC(&nd_tbl, rcv_probes_ucast);
 911
 912	/*
 913	 *	update / create cache entry
 914	 *	for the source address
 915	 */
 916	neigh = __neigh_lookup(&nd_tbl, saddr, dev,
 917			       !inc || lladdr || !dev->addr_len);
 918	if (neigh)
 919		ndisc_update(dev, neigh, lladdr, NUD_STALE,
 920			     NEIGH_UPDATE_F_WEAK_OVERRIDE|
 921			     NEIGH_UPDATE_F_OVERRIDE,
 922			     NDISC_NEIGHBOUR_SOLICITATION, &ndopts);
 923	if (neigh || !dev->header_ops) {
 924		ndisc_send_na(dev, saddr, &msg->target, !!is_router,
 925			      true, (ifp != NULL && inc), inc);
 
 926		if (neigh)
 927			neigh_release(neigh);
 928	}
 929
 930out:
 931	if (ifp)
 932		in6_ifa_put(ifp);
 933	else
 934		in6_dev_put(idev);
 935}
 936
 937static void ndisc_recv_na(struct sk_buff *skb)
 938{
 939	struct nd_msg *msg = (struct nd_msg *)skb_transport_header(skb);
 940	struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
 941	const struct in6_addr *daddr = &ipv6_hdr(skb)->daddr;
 942	u8 *lladdr = NULL;
 943	u32 ndoptlen = skb_tail_pointer(skb) - (skb_transport_header(skb) +
 944				    offsetof(struct nd_msg, opt));
 945	struct ndisc_options ndopts;
 946	struct net_device *dev = skb->dev;
 947	struct inet6_dev *idev = __in6_dev_get(dev);
 948	struct inet6_ifaddr *ifp;
 949	struct neighbour *neigh;
 950
 951	if (skb->len < sizeof(struct nd_msg)) {
 952		ND_PRINTK(2, warn, "NA: packet too short\n");
 
 953		return;
 954	}
 955
 956	if (ipv6_addr_is_multicast(&msg->target)) {
 957		ND_PRINTK(2, warn, "NA: target address is multicast\n");
 
 958		return;
 959	}
 960
 961	if (ipv6_addr_is_multicast(daddr) &&
 962	    msg->icmph.icmp6_solicited) {
 963		ND_PRINTK(2, warn, "NA: solicited NA is multicasted\n");
 
 964		return;
 965	}
 966
 967	/* For some 802.11 wireless deployments (and possibly other networks),
 968	 * there will be a NA proxy and unsolicitd packets are attacks
 969	 * and thus should not be accepted.
 970	 */
 971	if (!msg->icmph.icmp6_solicited && idev &&
 972	    idev->cnf.drop_unsolicited_na)
 973		return;
 974
 975	if (!ndisc_parse_options(dev, msg->opt, ndoptlen, &ndopts)) {
 976		ND_PRINTK(2, warn, "NS: invalid ND option\n");
 977		return;
 978	}
 979	if (ndopts.nd_opts_tgt_lladdr) {
 980		lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr, dev);
 981		if (!lladdr) {
 982			ND_PRINTK(2, warn,
 983				  "NA: invalid link-layer address length\n");
 984			return;
 985		}
 986	}
 987	ifp = ipv6_get_ifaddr(dev_net(dev), &msg->target, dev, 1);
 988	if (ifp) {
 989		if (skb->pkt_type != PACKET_LOOPBACK
 990		    && (ifp->flags & IFA_F_TENTATIVE)) {
 991				addrconf_dad_failure(skb, ifp);
 992				return;
 993		}
 994		/* What should we make now? The advertisement
 995		   is invalid, but ndisc specs say nothing
 996		   about it. It could be misconfiguration, or
 997		   an smart proxy agent tries to help us :-)
 998
 999		   We should not print the error if NA has been
1000		   received from loopback - it is just our own
1001		   unsolicited advertisement.
1002		 */
1003		if (skb->pkt_type != PACKET_LOOPBACK)
1004			ND_PRINTK(1, warn,
1005				  "NA: %pM advertised our address %pI6c on %s!\n",
1006				  eth_hdr(skb)->h_source, &ifp->addr, ifp->idev->dev->name);
1007		in6_ifa_put(ifp);
1008		return;
1009	}
1010	neigh = neigh_lookup(&nd_tbl, &msg->target, dev);
1011
1012	if (neigh) {
1013		u8 old_flags = neigh->flags;
1014		struct net *net = dev_net(dev);
1015
1016		if (neigh->nud_state & NUD_FAILED)
1017			goto out;
1018
1019		/*
1020		 * Don't update the neighbor cache entry on a proxy NA from
1021		 * ourselves because either the proxied node is off link or it
1022		 * has already sent a NA to us.
1023		 */
1024		if (lladdr && !memcmp(lladdr, dev->dev_addr, dev->addr_len) &&
1025		    net->ipv6.devconf_all->forwarding && net->ipv6.devconf_all->proxy_ndp &&
1026		    pneigh_lookup(&nd_tbl, net, &msg->target, dev, 0)) {
1027			/* XXX: idev->cnf.proxy_ndp */
1028			goto out;
1029		}
1030
1031		ndisc_update(dev, neigh, lladdr,
1032			     msg->icmph.icmp6_solicited ? NUD_REACHABLE : NUD_STALE,
1033			     NEIGH_UPDATE_F_WEAK_OVERRIDE|
1034			     (msg->icmph.icmp6_override ? NEIGH_UPDATE_F_OVERRIDE : 0)|
1035			     NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
1036			     (msg->icmph.icmp6_router ? NEIGH_UPDATE_F_ISROUTER : 0),
1037			     NDISC_NEIGHBOUR_ADVERTISEMENT, &ndopts);
1038
1039		if ((old_flags & ~neigh->flags) & NTF_ROUTER) {
1040			/*
1041			 * Change: router to host
1042			 */
1043			rt6_clean_tohost(dev_net(dev),  saddr);
 
 
 
1044		}
1045
1046out:
1047		neigh_release(neigh);
1048	}
1049}
1050
1051static void ndisc_recv_rs(struct sk_buff *skb)
1052{
1053	struct rs_msg *rs_msg = (struct rs_msg *)skb_transport_header(skb);
1054	unsigned long ndoptlen = skb->len - sizeof(*rs_msg);
1055	struct neighbour *neigh;
1056	struct inet6_dev *idev;
1057	const struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
1058	struct ndisc_options ndopts;
1059	u8 *lladdr = NULL;
1060
1061	if (skb->len < sizeof(*rs_msg))
1062		return;
1063
1064	idev = __in6_dev_get(skb->dev);
1065	if (!idev) {
1066		ND_PRINTK(1, err, "RS: can't find in6 device\n");
 
1067		return;
1068	}
1069
1070	/* Don't accept RS if we're not in router mode */
1071	if (!idev->cnf.forwarding)
1072		goto out;
1073
1074	/*
1075	 * Don't update NCE if src = ::;
1076	 * this implies that the source node has no ip address assigned yet.
1077	 */
1078	if (ipv6_addr_any(saddr))
1079		goto out;
1080
1081	/* Parse ND options */
1082	if (!ndisc_parse_options(skb->dev, rs_msg->opt, ndoptlen, &ndopts)) {
1083		ND_PRINTK(2, notice, "NS: invalid ND option, ignored\n");
 
1084		goto out;
1085	}
1086
1087	if (ndopts.nd_opts_src_lladdr) {
1088		lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr,
1089					     skb->dev);
1090		if (!lladdr)
1091			goto out;
1092	}
1093
1094	neigh = __neigh_lookup(&nd_tbl, saddr, skb->dev, 1);
1095	if (neigh) {
1096		ndisc_update(skb->dev, neigh, lladdr, NUD_STALE,
1097			     NEIGH_UPDATE_F_WEAK_OVERRIDE|
1098			     NEIGH_UPDATE_F_OVERRIDE|
1099			     NEIGH_UPDATE_F_OVERRIDE_ISROUTER,
1100			     NDISC_ROUTER_SOLICITATION, &ndopts);
1101		neigh_release(neigh);
1102	}
1103out:
1104	return;
1105}
1106
1107static void ndisc_ra_useropt(struct sk_buff *ra, struct nd_opt_hdr *opt)
1108{
1109	struct icmp6hdr *icmp6h = (struct icmp6hdr *)skb_transport_header(ra);
1110	struct sk_buff *skb;
1111	struct nlmsghdr *nlh;
1112	struct nduseroptmsg *ndmsg;
1113	struct net *net = dev_net(ra->dev);
1114	int err;
1115	int base_size = NLMSG_ALIGN(sizeof(struct nduseroptmsg)
1116				    + (opt->nd_opt_len << 3));
1117	size_t msg_size = base_size + nla_total_size(sizeof(struct in6_addr));
1118
1119	skb = nlmsg_new(msg_size, GFP_ATOMIC);
1120	if (!skb) {
1121		err = -ENOBUFS;
1122		goto errout;
1123	}
1124
1125	nlh = nlmsg_put(skb, 0, 0, RTM_NEWNDUSEROPT, base_size, 0);
1126	if (!nlh) {
1127		goto nla_put_failure;
1128	}
1129
1130	ndmsg = nlmsg_data(nlh);
1131	ndmsg->nduseropt_family = AF_INET6;
1132	ndmsg->nduseropt_ifindex = ra->dev->ifindex;
1133	ndmsg->nduseropt_icmp_type = icmp6h->icmp6_type;
1134	ndmsg->nduseropt_icmp_code = icmp6h->icmp6_code;
1135	ndmsg->nduseropt_opts_len = opt->nd_opt_len << 3;
1136
1137	memcpy(ndmsg + 1, opt, opt->nd_opt_len << 3);
1138
1139	if (nla_put_in6_addr(skb, NDUSEROPT_SRCADDR, &ipv6_hdr(ra)->saddr))
1140		goto nla_put_failure;
1141	nlmsg_end(skb, nlh);
1142
1143	rtnl_notify(skb, net, 0, RTNLGRP_ND_USEROPT, NULL, GFP_ATOMIC);
1144	return;
1145
1146nla_put_failure:
1147	nlmsg_free(skb);
1148	err = -EMSGSIZE;
1149errout:
1150	rtnl_set_sk_err(net, RTNLGRP_ND_USEROPT, err);
1151}
1152
 
 
 
 
 
 
 
 
 
 
 
 
1153static void ndisc_router_discovery(struct sk_buff *skb)
1154{
1155	struct ra_msg *ra_msg = (struct ra_msg *)skb_transport_header(skb);
1156	struct neighbour *neigh = NULL;
1157	struct inet6_dev *in6_dev;
1158	struct rt6_info *rt = NULL;
1159	int lifetime;
1160	struct ndisc_options ndopts;
1161	int optlen;
1162	unsigned int pref = 0;
1163	__u32 old_if_flags;
1164	bool send_ifinfo_notify = false;
1165
1166	__u8 *opt = (__u8 *)(ra_msg + 1);
1167
1168	optlen = (skb_tail_pointer(skb) - skb_transport_header(skb)) -
1169		sizeof(struct ra_msg);
1170
1171	ND_PRINTK(2, info,
1172		  "RA: %s, dev: %s\n",
1173		  __func__, skb->dev->name);
1174	if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) {
1175		ND_PRINTK(2, warn, "RA: source address is not link-local\n");
 
1176		return;
1177	}
1178	if (optlen < 0) {
1179		ND_PRINTK(2, warn, "RA: packet too short\n");
 
1180		return;
1181	}
1182
1183#ifdef CONFIG_IPV6_NDISC_NODETYPE
1184	if (skb->ndisc_nodetype == NDISC_NODETYPE_HOST) {
1185		ND_PRINTK(2, warn, "RA: from host or unauthorized router\n");
 
1186		return;
1187	}
1188#endif
1189
1190	/*
1191	 *	set the RA_RECV flag in the interface
1192	 */
1193
1194	in6_dev = __in6_dev_get(skb->dev);
1195	if (!in6_dev) {
1196		ND_PRINTK(0, err, "RA: can't find inet6 device for %s\n",
1197			  skb->dev->name);
 
1198		return;
1199	}
1200
1201	if (!ndisc_parse_options(skb->dev, opt, optlen, &ndopts)) {
1202		ND_PRINTK(2, warn, "RA: invalid ND options\n");
 
 
1203		return;
1204	}
1205
1206	if (!ipv6_accept_ra(in6_dev)) {
1207		ND_PRINTK(2, info,
1208			  "RA: %s, did not accept ra for dev: %s\n",
1209			  __func__, skb->dev->name);
1210		goto skip_linkparms;
1211	}
1212
1213#ifdef CONFIG_IPV6_NDISC_NODETYPE
1214	/* skip link-specific parameters from interior routers */
1215	if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT) {
1216		ND_PRINTK(2, info,
1217			  "RA: %s, nodetype is NODEFAULT, dev: %s\n",
1218			  __func__, skb->dev->name);
1219		goto skip_linkparms;
1220	}
1221#endif
1222
1223	if (in6_dev->if_flags & IF_RS_SENT) {
1224		/*
1225		 *	flag that an RA was received after an RS was sent
1226		 *	out on this interface.
1227		 */
1228		in6_dev->if_flags |= IF_RA_RCVD;
1229	}
1230
1231	/*
1232	 * Remember the managed/otherconf flags from most recently
1233	 * received RA message (RFC 2462) -- yoshfuji
1234	 */
1235	old_if_flags = in6_dev->if_flags;
1236	in6_dev->if_flags = (in6_dev->if_flags & ~(IF_RA_MANAGED |
1237				IF_RA_OTHERCONF)) |
1238				(ra_msg->icmph.icmp6_addrconf_managed ?
1239					IF_RA_MANAGED : 0) |
1240				(ra_msg->icmph.icmp6_addrconf_other ?
1241					IF_RA_OTHERCONF : 0);
1242
1243	if (old_if_flags != in6_dev->if_flags)
1244		send_ifinfo_notify = true;
1245
1246	if (!in6_dev->cnf.accept_ra_defrtr) {
1247		ND_PRINTK(2, info,
1248			  "RA: %s, defrtr is false for dev: %s\n",
1249			  __func__, skb->dev->name);
1250		goto skip_defrtr;
1251	}
1252
1253	/* Do not accept RA with source-addr found on local machine unless
1254	 * accept_ra_from_local is set to true.
1255	 */
1256	if (!in6_dev->cnf.accept_ra_from_local &&
1257	    ipv6_chk_addr(dev_net(in6_dev->dev), &ipv6_hdr(skb)->saddr,
1258			  in6_dev->dev, 0)) {
1259		ND_PRINTK(2, info,
1260			  "RA from local address detected on dev: %s: default router ignored\n",
1261			  skb->dev->name);
1262		goto skip_defrtr;
1263	}
1264
1265	lifetime = ntohs(ra_msg->icmph.icmp6_rt_lifetime);
1266
1267#ifdef CONFIG_IPV6_ROUTER_PREF
1268	pref = ra_msg->icmph.icmp6_router_pref;
1269	/* 10b is handled as if it were 00b (medium) */
1270	if (pref == ICMPV6_ROUTER_PREF_INVALID ||
1271	    !in6_dev->cnf.accept_ra_rtr_pref)
1272		pref = ICMPV6_ROUTER_PREF_MEDIUM;
1273#endif
1274
1275	rt = rt6_get_dflt_router(&ipv6_hdr(skb)->saddr, skb->dev);
1276
1277	if (rt) {
1278		neigh = dst_neigh_lookup(&rt->dst, &ipv6_hdr(skb)->saddr);
1279		if (!neigh) {
1280			ND_PRINTK(0, err,
1281				  "RA: %s got default router without neighbour\n",
1282				  __func__);
1283			ip6_rt_put(rt);
1284			return;
1285		}
1286	}
1287	if (rt && lifetime == 0) {
 
1288		ip6_del_rt(rt);
1289		rt = NULL;
1290	}
1291
1292	ND_PRINTK(3, info, "RA: rt: %p  lifetime: %d, for dev: %s\n",
1293		  rt, lifetime, skb->dev->name);
1294	if (!rt && lifetime) {
1295		ND_PRINTK(3, info, "RA: adding default router\n");
1296
1297		rt = rt6_add_dflt_router(&ipv6_hdr(skb)->saddr, skb->dev, pref);
1298		if (!rt) {
1299			ND_PRINTK(0, err,
1300				  "RA: %s failed to add default route\n",
1301				  __func__);
 
1302			return;
1303		}
1304
1305		neigh = dst_neigh_lookup(&rt->dst, &ipv6_hdr(skb)->saddr);
1306		if (!neigh) {
1307			ND_PRINTK(0, err,
1308				  "RA: %s got default router without neighbour\n",
1309				  __func__);
1310			ip6_rt_put(rt);
 
1311			return;
1312		}
1313		neigh->flags |= NTF_ROUTER;
1314	} else if (rt) {
1315		rt->rt6i_flags = (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
1316	}
1317
1318	if (rt)
1319		rt6_set_expires(rt, jiffies + (HZ * lifetime));
1320	if (in6_dev->cnf.accept_ra_min_hop_limit < 256 &&
1321	    ra_msg->icmph.icmp6_hop_limit) {
1322		if (in6_dev->cnf.accept_ra_min_hop_limit <= ra_msg->icmph.icmp6_hop_limit) {
1323			in6_dev->cnf.hop_limit = ra_msg->icmph.icmp6_hop_limit;
1324			if (rt)
1325				dst_metric_set(&rt->dst, RTAX_HOPLIMIT,
1326					       ra_msg->icmph.icmp6_hop_limit);
1327		} else {
1328			ND_PRINTK(2, warn, "RA: Got route advertisement with lower hop_limit than minimum\n");
1329		}
1330	}
1331
1332skip_defrtr:
1333
1334	/*
1335	 *	Update Reachable Time and Retrans Timer
1336	 */
1337
1338	if (in6_dev->nd_parms) {
1339		unsigned long rtime = ntohl(ra_msg->retrans_timer);
1340
1341		if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/HZ) {
1342			rtime = (rtime*HZ)/1000;
1343			if (rtime < HZ/10)
1344				rtime = HZ/10;
1345			NEIGH_VAR_SET(in6_dev->nd_parms, RETRANS_TIME, rtime);
1346			in6_dev->tstamp = jiffies;
1347			send_ifinfo_notify = true;
1348		}
1349
1350		rtime = ntohl(ra_msg->reachable_time);
1351		if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/(3*HZ)) {
1352			rtime = (rtime*HZ)/1000;
1353
1354			if (rtime < HZ/10)
1355				rtime = HZ/10;
1356
1357			if (rtime != NEIGH_VAR(in6_dev->nd_parms, BASE_REACHABLE_TIME)) {
1358				NEIGH_VAR_SET(in6_dev->nd_parms,
1359					      BASE_REACHABLE_TIME, rtime);
1360				NEIGH_VAR_SET(in6_dev->nd_parms,
1361					      GC_STALETIME, 3 * rtime);
1362				in6_dev->nd_parms->reachable_time = neigh_rand_reach_time(rtime);
1363				in6_dev->tstamp = jiffies;
1364				send_ifinfo_notify = true;
1365			}
1366		}
1367	}
1368
1369	/*
1370	 *	Send a notify if RA changed managed/otherconf flags or timer settings
1371	 */
1372	if (send_ifinfo_notify)
1373		inet6_ifinfo_notify(RTM_NEWLINK, in6_dev);
1374
1375skip_linkparms:
1376
1377	/*
1378	 *	Process options.
1379	 */
1380
1381	if (!neigh)
1382		neigh = __neigh_lookup(&nd_tbl, &ipv6_hdr(skb)->saddr,
1383				       skb->dev, 1);
1384	if (neigh) {
1385		u8 *lladdr = NULL;
1386		if (ndopts.nd_opts_src_lladdr) {
1387			lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr,
1388						     skb->dev);
1389			if (!lladdr) {
1390				ND_PRINTK(2, warn,
1391					  "RA: invalid link-layer address length\n");
1392				goto out;
1393			}
1394		}
1395		ndisc_update(skb->dev, neigh, lladdr, NUD_STALE,
1396			     NEIGH_UPDATE_F_WEAK_OVERRIDE|
1397			     NEIGH_UPDATE_F_OVERRIDE|
1398			     NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
1399			     NEIGH_UPDATE_F_ISROUTER,
1400			     NDISC_ROUTER_ADVERTISEMENT, &ndopts);
1401	}
1402
1403	if (!ipv6_accept_ra(in6_dev)) {
1404		ND_PRINTK(2, info,
1405			  "RA: %s, accept_ra is false for dev: %s\n",
1406			  __func__, skb->dev->name);
1407		goto out;
1408	}
1409
1410#ifdef CONFIG_IPV6_ROUTE_INFO
1411	if (!in6_dev->cnf.accept_ra_from_local &&
1412	    ipv6_chk_addr(dev_net(in6_dev->dev), &ipv6_hdr(skb)->saddr,
1413			  in6_dev->dev, 0)) {
1414		ND_PRINTK(2, info,
1415			  "RA from local address detected on dev: %s: router info ignored.\n",
1416			  skb->dev->name);
1417		goto skip_routeinfo;
1418	}
1419
1420	if (in6_dev->cnf.accept_ra_rtr_pref && ndopts.nd_opts_ri) {
1421		struct nd_opt_hdr *p;
1422		for (p = ndopts.nd_opts_ri;
1423		     p;
1424		     p = ndisc_next_option(p, ndopts.nd_opts_ri_end)) {
1425			struct route_info *ri = (struct route_info *)p;
1426#ifdef CONFIG_IPV6_NDISC_NODETYPE
1427			if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT &&
1428			    ri->prefix_len == 0)
1429				continue;
1430#endif
1431			if (ri->prefix_len == 0 &&
1432			    !in6_dev->cnf.accept_ra_defrtr)
1433				continue;
1434			if (ri->prefix_len < in6_dev->cnf.accept_ra_rt_info_min_plen)
1435				continue;
1436			if (ri->prefix_len > in6_dev->cnf.accept_ra_rt_info_max_plen)
1437				continue;
1438			rt6_route_rcv(skb->dev, (u8 *)p, (p->nd_opt_len) << 3,
1439				      &ipv6_hdr(skb)->saddr);
1440		}
1441	}
1442
1443skip_routeinfo:
1444#endif
1445
1446#ifdef CONFIG_IPV6_NDISC_NODETYPE
1447	/* skip link-specific ndopts from interior routers */
1448	if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT) {
1449		ND_PRINTK(2, info,
1450			  "RA: %s, nodetype is NODEFAULT (interior routes), dev: %s\n",
1451			  __func__, skb->dev->name);
1452		goto out;
1453	}
1454#endif
1455
1456	if (in6_dev->cnf.accept_ra_pinfo && ndopts.nd_opts_pi) {
1457		struct nd_opt_hdr *p;
1458		for (p = ndopts.nd_opts_pi;
1459		     p;
1460		     p = ndisc_next_option(p, ndopts.nd_opts_pi_end)) {
1461			addrconf_prefix_rcv(skb->dev, (u8 *)p,
1462					    (p->nd_opt_len) << 3,
1463					    ndopts.nd_opts_src_lladdr != NULL);
1464		}
1465	}
1466
1467	if (ndopts.nd_opts_mtu && in6_dev->cnf.accept_ra_mtu) {
1468		__be32 n;
1469		u32 mtu;
1470
1471		memcpy(&n, ((u8 *)(ndopts.nd_opts_mtu+1))+2, sizeof(mtu));
1472		mtu = ntohl(n);
1473
1474		if (mtu < IPV6_MIN_MTU || mtu > skb->dev->mtu) {
1475			ND_PRINTK(2, warn, "RA: invalid mtu: %d\n", mtu);
 
 
1476		} else if (in6_dev->cnf.mtu6 != mtu) {
1477			in6_dev->cnf.mtu6 = mtu;
1478
1479			if (rt)
1480				dst_metric_set(&rt->dst, RTAX_MTU, mtu);
1481
1482			rt6_mtu_change(skb->dev, mtu);
1483		}
1484	}
1485
1486	if (ndopts.nd_useropts) {
1487		struct nd_opt_hdr *p;
1488		for (p = ndopts.nd_useropts;
1489		     p;
1490		     p = ndisc_next_useropt(skb->dev, p,
1491					    ndopts.nd_useropts_end)) {
1492			ndisc_ra_useropt(skb, p);
1493		}
1494	}
1495
1496	if (ndopts.nd_opts_tgt_lladdr || ndopts.nd_opts_rh) {
1497		ND_PRINTK(2, warn, "RA: invalid RA options\n");
 
1498	}
1499out:
1500	ip6_rt_put(rt);
1501	if (neigh)
 
1502		neigh_release(neigh);
 
1503}
1504
1505static void ndisc_redirect_rcv(struct sk_buff *skb)
1506{
1507	u8 *hdr;
 
 
 
 
 
1508	struct ndisc_options ndopts;
1509	struct rd_msg *msg = (struct rd_msg *)skb_transport_header(skb);
1510	u32 ndoptlen = skb_tail_pointer(skb) - (skb_transport_header(skb) +
1511				    offsetof(struct rd_msg, opt));
1512
1513#ifdef CONFIG_IPV6_NDISC_NODETYPE
1514	switch (skb->ndisc_nodetype) {
1515	case NDISC_NODETYPE_HOST:
1516	case NDISC_NODETYPE_NODEFAULT:
1517		ND_PRINTK(2, warn,
1518			  "Redirect: from host or unauthorized router\n");
1519		return;
1520	}
1521#endif
1522
1523	if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) {
1524		ND_PRINTK(2, warn,
1525			  "Redirect: source address is not link-local\n");
1526		return;
1527	}
1528
1529	if (!ndisc_parse_options(skb->dev, msg->opt, ndoptlen, &ndopts))
 
 
 
 
 
1530		return;
 
 
 
 
 
1531
1532	if (!ndopts.nd_opts_rh) {
1533		ip6_redirect_no_header(skb, dev_net(skb->dev),
1534					skb->dev->ifindex, 0);
1535		return;
1536	}
1537
1538	hdr = (u8 *)ndopts.nd_opts_rh;
1539	hdr += 8;
1540	if (!pskb_pull(skb, hdr - skb_transport_header(skb)))
 
 
 
1541		return;
 
1542
1543	icmpv6_notify(skb, NDISC_REDIRECT, 0, 0);
1544}
 
 
 
 
 
1545
1546static void ndisc_fill_redirect_hdr_option(struct sk_buff *skb,
1547					   struct sk_buff *orig_skb,
1548					   int rd_len)
1549{
1550	u8 *opt = skb_put(skb, rd_len);
1551
1552	memset(opt, 0, 8);
1553	*(opt++) = ND_OPT_REDIRECT_HDR;
1554	*(opt++) = (rd_len >> 3);
1555	opt += 6;
 
 
 
 
 
 
 
 
 
 
 
 
1556
1557	skb_copy_bits(orig_skb, skb_network_offset(orig_skb), opt,
1558		      rd_len - 8);
 
 
 
 
 
 
1559}
1560
1561void ndisc_send_redirect(struct sk_buff *skb, const struct in6_addr *target)
 
1562{
1563	struct net_device *dev = skb->dev;
1564	struct net *net = dev_net(dev);
1565	struct sock *sk = net->ipv6.ndisc_sk;
1566	int optlen = 0;
1567	struct inet_peer *peer;
1568	struct sk_buff *buff;
1569	struct rd_msg *msg;
1570	struct in6_addr saddr_buf;
 
1571	struct rt6_info *rt;
1572	struct dst_entry *dst;
 
1573	struct flowi6 fl6;
 
1574	int rd_len;
1575	u8 ha_buf[MAX_ADDR_LEN], *ha = NULL,
1576	   ops_data_buf[NDISC_OPS_REDIRECT_DATA_SPACE], *ops_data = NULL;
1577	bool ret;
1578
1579	if (ipv6_get_lladdr(dev, &saddr_buf, IFA_F_TENTATIVE)) {
1580		ND_PRINTK(2, warn, "Redirect: no link-local address on %s\n",
1581			  dev->name);
 
1582		return;
1583	}
1584
1585	if (!ipv6_addr_equal(&ipv6_hdr(skb)->daddr, target) &&
1586	    ipv6_addr_type(target) != (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
1587		ND_PRINTK(2, warn,
1588			  "Redirect: target address is not link-local unicast\n");
1589		return;
1590	}
1591
1592	icmpv6_flow_init(sk, &fl6, NDISC_REDIRECT,
1593			 &saddr_buf, &ipv6_hdr(skb)->saddr, dev->ifindex);
1594
1595	dst = ip6_route_output(net, NULL, &fl6);
1596	if (dst->error) {
1597		dst_release(dst);
1598		return;
1599	}
1600	dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), NULL, 0);
1601	if (IS_ERR(dst))
1602		return;
1603
1604	rt = (struct rt6_info *) dst;
1605
1606	if (rt->rt6i_flags & RTF_GATEWAY) {
1607		ND_PRINTK(2, warn,
1608			  "Redirect: destination is not a neighbour\n");
1609		goto release;
1610	}
1611	peer = inet_getpeer_v6(net->ipv6.peers, &ipv6_hdr(skb)->saddr, 1);
1612	ret = inet_peer_xrlim_allow(peer, 1*HZ);
1613	if (peer)
1614		inet_putpeer(peer);
1615	if (!ret)
1616		goto release;
1617
1618	if (dev->addr_len) {
1619		struct neighbour *neigh = dst_neigh_lookup(skb_dst(skb), target);
1620		if (!neigh) {
1621			ND_PRINTK(2, warn,
1622				  "Redirect: no neigh for target address\n");
1623			goto release;
1624		}
1625
1626		read_lock_bh(&neigh->lock);
1627		if (neigh->nud_state & NUD_VALID) {
1628			memcpy(ha_buf, neigh->ha, dev->addr_len);
1629			read_unlock_bh(&neigh->lock);
1630			ha = ha_buf;
1631			optlen += ndisc_redirect_opt_addr_space(dev, neigh,
1632								ops_data_buf,
1633								&ops_data);
1634		} else
1635			read_unlock_bh(&neigh->lock);
1636
1637		neigh_release(neigh);
1638	}
1639
1640	rd_len = min_t(unsigned int,
1641		       IPV6_MIN_MTU - sizeof(struct ipv6hdr) - sizeof(*msg) - optlen,
1642		       skb->len + 8);
1643	rd_len &= ~0x7;
1644	optlen += rd_len;
1645
1646	buff = ndisc_alloc_skb(dev, sizeof(*msg) + optlen);
1647	if (!buff)
 
 
 
 
 
 
1648		goto release;
 
1649
1650	msg = skb_put(buff, sizeof(*msg));
1651	*msg = (struct rd_msg) {
1652		.icmph = {
1653			.icmp6_type = NDISC_REDIRECT,
1654		},
1655		.target = *target,
1656		.dest = ipv6_hdr(skb)->daddr,
1657	};
 
 
 
 
 
 
 
 
 
 
 
 
 
1658
1659	/*
1660	 *	include target_address option
1661	 */
1662
1663	if (ha)
1664		ndisc_fill_redirect_addr_option(buff, ha, ops_data);
 
1665
1666	/*
1667	 *	build redirect option and copy skb over to the new packet.
1668	 */
1669
1670	if (rd_len)
1671		ndisc_fill_redirect_hdr_option(buff, skb, rd_len);
 
 
 
 
 
 
 
 
1672
1673	skb_dst_set(buff, dst);
1674	ndisc_send_skb(buff, &ipv6_hdr(skb)->saddr, &saddr_buf);
 
 
 
 
 
 
 
 
 
 
1675	return;
1676
1677release:
1678	dst_release(dst);
1679}
1680
1681static void pndisc_redo(struct sk_buff *skb)
1682{
1683	ndisc_recv_ns(skb);
1684	kfree_skb(skb);
1685}
1686
1687static bool ndisc_suppress_frag_ndisc(struct sk_buff *skb)
1688{
1689	struct inet6_dev *idev = __in6_dev_get(skb->dev);
1690
1691	if (!idev)
1692		return true;
1693	if (IP6CB(skb)->flags & IP6SKB_FRAGMENTED &&
1694	    idev->cnf.suppress_frag_ndisc) {
1695		net_warn_ratelimited("Received fragmented ndisc packet. Carefully consider disabling suppress_frag_ndisc.\n");
1696		return true;
1697	}
1698	return false;
1699}
1700
1701int ndisc_rcv(struct sk_buff *skb)
1702{
1703	struct nd_msg *msg;
1704
1705	if (ndisc_suppress_frag_ndisc(skb))
1706		return 0;
1707
1708	if (skb_linearize(skb))
1709		return 0;
1710
1711	msg = (struct nd_msg *)skb_transport_header(skb);
1712
1713	__skb_push(skb, skb->data - skb_transport_header(skb));
1714
1715	if (ipv6_hdr(skb)->hop_limit != 255) {
1716		ND_PRINTK(2, warn, "NDISC: invalid hop-limit: %d\n",
1717			  ipv6_hdr(skb)->hop_limit);
 
1718		return 0;
1719	}
1720
1721	if (msg->icmph.icmp6_code != 0) {
1722		ND_PRINTK(2, warn, "NDISC: invalid ICMPv6 code: %d\n",
1723			  msg->icmph.icmp6_code);
 
1724		return 0;
1725	}
1726
1727	memset(NEIGH_CB(skb), 0, sizeof(struct neighbour_cb));
1728
1729	switch (msg->icmph.icmp6_type) {
1730	case NDISC_NEIGHBOUR_SOLICITATION:
1731		ndisc_recv_ns(skb);
1732		break;
1733
1734	case NDISC_NEIGHBOUR_ADVERTISEMENT:
1735		ndisc_recv_na(skb);
1736		break;
1737
1738	case NDISC_ROUTER_SOLICITATION:
1739		ndisc_recv_rs(skb);
1740		break;
1741
1742	case NDISC_ROUTER_ADVERTISEMENT:
1743		ndisc_router_discovery(skb);
1744		break;
1745
1746	case NDISC_REDIRECT:
1747		ndisc_redirect_rcv(skb);
1748		break;
1749	}
1750
1751	return 0;
1752}
1753
1754static int ndisc_netdev_event(struct notifier_block *this, unsigned long event, void *ptr)
1755{
1756	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1757	struct netdev_notifier_change_info *change_info;
1758	struct net *net = dev_net(dev);
1759	struct inet6_dev *idev;
1760
1761	switch (event) {
1762	case NETDEV_CHANGEADDR:
1763		neigh_changeaddr(&nd_tbl, dev);
1764		fib6_run_gc(0, net, false);
1765		/* fallthrough */
1766	case NETDEV_UP:
1767		idev = in6_dev_get(dev);
1768		if (!idev)
1769			break;
1770		if (idev->cnf.ndisc_notify ||
1771		    net->ipv6.devconf_all->ndisc_notify)
1772			ndisc_send_unsol_na(dev);
1773		in6_dev_put(idev);
1774		break;
1775	case NETDEV_CHANGE:
1776		change_info = ptr;
1777		if (change_info->flags_changed & IFF_NOARP)
1778			neigh_changeaddr(&nd_tbl, dev);
1779		break;
1780	case NETDEV_DOWN:
1781		neigh_ifdown(&nd_tbl, dev);
1782		fib6_run_gc(0, net, false);
1783		break;
1784	case NETDEV_NOTIFY_PEERS:
1785		ndisc_send_unsol_na(dev);
1786		break;
1787	default:
1788		break;
1789	}
1790
1791	return NOTIFY_DONE;
1792}
1793
1794static struct notifier_block ndisc_netdev_notifier = {
1795	.notifier_call = ndisc_netdev_event,
1796	.priority = ADDRCONF_NOTIFY_PRIORITY - 5,
1797};
1798
1799#ifdef CONFIG_SYSCTL
1800static void ndisc_warn_deprecated_sysctl(struct ctl_table *ctl,
1801					 const char *func, const char *dev_name)
1802{
1803	static char warncomm[TASK_COMM_LEN];
1804	static int warned;
1805	if (strcmp(warncomm, current->comm) && warned < 5) {
1806		strcpy(warncomm, current->comm);
1807		pr_warn("process `%s' is using deprecated sysctl (%s) net.ipv6.neigh.%s.%s - use net.ipv6.neigh.%s.%s_ms instead\n",
 
 
 
 
1808			warncomm, func,
1809			dev_name, ctl->procname,
1810			dev_name, ctl->procname);
1811		warned++;
1812	}
1813}
1814
1815int ndisc_ifinfo_sysctl_change(struct ctl_table *ctl, int write, void __user *buffer, size_t *lenp, loff_t *ppos)
1816{
1817	struct net_device *dev = ctl->extra1;
1818	struct inet6_dev *idev;
1819	int ret;
1820
1821	if ((strcmp(ctl->procname, "retrans_time") == 0) ||
1822	    (strcmp(ctl->procname, "base_reachable_time") == 0))
1823		ndisc_warn_deprecated_sysctl(ctl, "syscall", dev ? dev->name : "default");
1824
1825	if (strcmp(ctl->procname, "retrans_time") == 0)
1826		ret = neigh_proc_dointvec(ctl, write, buffer, lenp, ppos);
1827
1828	else if (strcmp(ctl->procname, "base_reachable_time") == 0)
1829		ret = neigh_proc_dointvec_jiffies(ctl, write,
1830						  buffer, lenp, ppos);
1831
1832	else if ((strcmp(ctl->procname, "retrans_time_ms") == 0) ||
1833		 (strcmp(ctl->procname, "base_reachable_time_ms") == 0))
1834		ret = neigh_proc_dointvec_ms_jiffies(ctl, write,
1835						     buffer, lenp, ppos);
1836	else
1837		ret = -1;
1838
1839	if (write && ret == 0 && dev && (idev = in6_dev_get(dev)) != NULL) {
1840		if (ctl->data == &NEIGH_VAR(idev->nd_parms, BASE_REACHABLE_TIME))
1841			idev->nd_parms->reachable_time =
1842					neigh_rand_reach_time(NEIGH_VAR(idev->nd_parms, BASE_REACHABLE_TIME));
1843		idev->tstamp = jiffies;
1844		inet6_ifinfo_notify(RTM_NEWLINK, idev);
1845		in6_dev_put(idev);
1846	}
1847	return ret;
1848}
1849
1850
1851#endif
1852
1853static int __net_init ndisc_net_init(struct net *net)
1854{
1855	struct ipv6_pinfo *np;
1856	struct sock *sk;
1857	int err;
1858
1859	err = inet_ctl_sock_create(&sk, PF_INET6,
1860				   SOCK_RAW, IPPROTO_ICMPV6, net);
1861	if (err < 0) {
1862		ND_PRINTK(0, err,
1863			  "NDISC: Failed to initialize the control socket (err %d)\n",
1864			  err);
1865		return err;
1866	}
1867
1868	net->ipv6.ndisc_sk = sk;
1869
1870	np = inet6_sk(sk);
1871	np->hop_limit = 255;
1872	/* Do not loopback ndisc messages */
1873	np->mc_loop = 0;
1874
1875	return 0;
1876}
1877
1878static void __net_exit ndisc_net_exit(struct net *net)
1879{
1880	inet_ctl_sock_destroy(net->ipv6.ndisc_sk);
1881}
1882
1883static struct pernet_operations ndisc_net_ops = {
1884	.init = ndisc_net_init,
1885	.exit = ndisc_net_exit,
1886};
1887
1888int __init ndisc_init(void)
1889{
1890	int err;
1891
1892	err = register_pernet_subsys(&ndisc_net_ops);
1893	if (err)
1894		return err;
1895	/*
1896	 * Initialize the neighbour table
1897	 */
1898	neigh_table_init(NEIGH_ND_TABLE, &nd_tbl);
1899
1900#ifdef CONFIG_SYSCTL
1901	err = neigh_sysctl_register(NULL, &nd_tbl.parms,
1902				    ndisc_ifinfo_sysctl_change);
1903	if (err)
1904		goto out_unregister_pernet;
 
 
 
 
1905out:
1906#endif
1907	return err;
1908
 
1909#ifdef CONFIG_SYSCTL
 
1910out_unregister_pernet:
 
1911	unregister_pernet_subsys(&ndisc_net_ops);
1912	goto out;
1913#endif
1914}
1915
1916int __init ndisc_late_init(void)
1917{
1918	return register_netdevice_notifier(&ndisc_netdev_notifier);
1919}
1920
1921void ndisc_late_cleanup(void)
1922{
1923	unregister_netdevice_notifier(&ndisc_netdev_notifier);
1924}
1925
1926void ndisc_cleanup(void)
1927{
1928#ifdef CONFIG_SYSCTL
1929	neigh_sysctl_unregister(&nd_tbl.parms);
1930#endif
1931	neigh_table_clear(NEIGH_ND_TABLE, &nd_tbl);
1932	unregister_pernet_subsys(&ndisc_net_ops);
1933}