Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 1690 insertions, 0 deletions

diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c
new file mode 100644
index 000000000000..7c291f4e9edc
--- /dev/null
+++ b/net/ipv6/ndisc.c
@@ -0,0 +1,1690 @@
+/*
+ *	Neighbour Discovery for IPv6
+ *	Linux INET6 implementation 
+ *
+ *	Authors:
+ *	Pedro Roque		<roque@di.fc.ul.pt>	
+ *	Mike Shaver		<shaver@ingenia.com>
+ *
+ *	This program is free software; you can redistribute it and/or
+ *      modify it under the terms of the GNU General Public License
+ *      as published by the Free Software Foundation; either version
+ *      2 of the License, or (at your option) any later version.
+ */
+
+/*
+ *	Changes:
+ *
+ *	Lars Fenneberg			:	fixed MTU setting on receipt
+ *						of an RA.
+ *
+ *	Janos Farkas			:	kmalloc failure checks
+ *	Alexey Kuznetsov		:	state machine reworked
+ *						and moved to net/core.
+ *	Pekka Savola			:	RFC2461 validation
+ *	YOSHIFUJI Hideaki @USAGI	:	Verify ND options properly
+ */
+
+/* Set to 3 to get tracing... */
+#define ND_DEBUG 1
+
+#define ND_PRINTK(fmt, args...) do { if (net_ratelimit()) { printk(fmt, ## args); } } while(0)
+#define ND_NOPRINTK(x...) do { ; } while(0)
+#define ND_PRINTK0 ND_PRINTK
+#define ND_PRINTK1 ND_NOPRINTK
+#define ND_PRINTK2 ND_NOPRINTK
+#define ND_PRINTK3 ND_NOPRINTK
+#if ND_DEBUG >= 1
+#undef ND_PRINTK1
+#define ND_PRINTK1 ND_PRINTK
+#endif
+#if ND_DEBUG >= 2
+#undef ND_PRINTK2
+#define ND_PRINTK2 ND_PRINTK
+#endif
+#if ND_DEBUG >= 3
+#undef ND_PRINTK3
+#define ND_PRINTK3 ND_PRINTK
+#endif
+
+#include <linux/module.h>
+#include <linux/config.h>
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/socket.h>
+#include <linux/sockios.h>
+#include <linux/sched.h>
+#include <linux/net.h>
+#include <linux/in6.h>
+#include <linux/route.h>
+#include <linux/init.h>
+#include <linux/rcupdate.h>
+#ifdef CONFIG_SYSCTL
+#include <linux/sysctl.h>
+#endif
+
+#include <linux/if_arp.h>
+#include <linux/ipv6.h>
+#include <linux/icmpv6.h>
+#include <linux/jhash.h>
+
+#include <net/sock.h>
+#include <net/snmp.h>
+
+#include <net/ipv6.h>
+#include <net/protocol.h>
+#include <net/ndisc.h>
+#include <net/ip6_route.h>
+#include <net/addrconf.h>
+#include <net/icmp.h>
+
+#include <net/flow.h>
+#include <net/ip6_checksum.h>
+#include <linux/proc_fs.h>
+
+#include <linux/netfilter.h>
+#include <linux/netfilter_ipv6.h>
+
+static struct socket *ndisc_socket;
+
+static u32 ndisc_hash(const void *pkey, const struct net_device *dev);
+static int ndisc_constructor(struct neighbour *neigh);
+static void ndisc_solicit(struct neighbour *neigh, struct sk_buff *skb);
+static void ndisc_error_report(struct neighbour *neigh, struct sk_buff *skb);
+static int pndisc_constructor(struct pneigh_entry *n);
+static void pndisc_destructor(struct pneigh_entry *n);
+static void pndisc_redo(struct sk_buff *skb);
+
+static struct neigh_ops ndisc_generic_ops = {
+	.family =		AF_INET6,
+	.solicit =		ndisc_solicit,
+	.error_report =		ndisc_error_report,
+	.output =		neigh_resolve_output,
+	.connected_output =	neigh_connected_output,
+	.hh_output =		dev_queue_xmit,
+	.queue_xmit =		dev_queue_xmit,
+};
+
+static struct neigh_ops ndisc_hh_ops = {
+	.family =		AF_INET6,
+	.solicit =		ndisc_solicit,
+	.error_report =		ndisc_error_report,
+	.output =		neigh_resolve_output,
+	.connected_output =	neigh_resolve_output,
+	.hh_output =		dev_queue_xmit,
+	.queue_xmit =		dev_queue_xmit,
+};
+
+
+static struct neigh_ops ndisc_direct_ops = {
+	.family =		AF_INET6,
+	.output =		dev_queue_xmit,
+	.connected_output =	dev_queue_xmit,
+	.hh_output =		dev_queue_xmit,
+	.queue_xmit =		dev_queue_xmit,
+};
+
+struct neigh_table nd_tbl = {
+	.family =	AF_INET6,
+	.entry_size =	sizeof(struct neighbour) + sizeof(struct in6_addr),
+	.key_len =	sizeof(struct in6_addr),
+	.hash =		ndisc_hash,
+	.constructor =	ndisc_constructor,
+	.pconstructor =	pndisc_constructor,
+	.pdestructor =	pndisc_destructor,
+	.proxy_redo =	pndisc_redo,
+	.id =		"ndisc_cache",
+	.parms = {
+		.tbl =			&nd_tbl,
+		.base_reachable_time =	30 * HZ,
+		.retrans_time =	 1 * HZ,
+		.gc_staletime =	60 * HZ,
+		.reachable_time =		30 * HZ,
+		.delay_probe_time =	 5 * HZ,
+		.queue_len =		 3,
+		.ucast_probes =	 3,
+		.mcast_probes =	 3,
+		.anycast_delay =	 1 * HZ,
+		.proxy_delay =		(8 * HZ) / 10,
+		.proxy_qlen =		64,
+	},
+	.gc_interval =	  30 * HZ,
+	.gc_thresh1 =	 128,
+	.gc_thresh2 =	 512,
+	.gc_thresh3 =	1024,
+};
+
+/* ND options */
+struct ndisc_options {
+	struct nd_opt_hdr *nd_opt_array[__ND_OPT_MAX];
+};
+
+#define nd_opts_src_lladdr	nd_opt_array[ND_OPT_SOURCE_LL_ADDR]
+#define nd_opts_tgt_lladdr	nd_opt_array[ND_OPT_TARGET_LL_ADDR]
+#define nd_opts_pi		nd_opt_array[ND_OPT_PREFIX_INFO]
+#define nd_opts_pi_end		nd_opt_array[__ND_OPT_PREFIX_INFO_END]
+#define nd_opts_rh		nd_opt_array[ND_OPT_REDIRECT_HDR]
+#define nd_opts_mtu		nd_opt_array[ND_OPT_MTU]
+
+#define NDISC_OPT_SPACE(len) (((len)+2+7)&~7)
+
+/*
+ * Return the padding between the option length and the start of the
+ * link addr.  Currently only IP-over-InfiniBand needs this, although
+ * if RFC 3831 IPv6-over-Fibre Channel is ever implemented it may
+ * also need a pad of 2.
+ */
+static int ndisc_addr_option_pad(unsigned short type)
+{
+	switch (type) {
+	case ARPHRD_INFINIBAND: return 2;
+	default:                return 0;
+	}
+}
+
+static inline int ndisc_opt_addr_space(struct net_device *dev)
+{
+	return NDISC_OPT_SPACE(dev->addr_len + ndisc_addr_option_pad(dev->type));
+}
+
+static u8 *ndisc_fill_addr_option(u8 *opt, int type, void *data, int data_len,
+				  unsigned short addr_type)
+{
+	int space = NDISC_OPT_SPACE(data_len);
+	int pad   = ndisc_addr_option_pad(addr_type);
+
+	opt[0] = type;
+	opt[1] = space>>3;
+
+	memset(opt + 2, 0, pad);
+	opt   += pad;
+	space -= pad;
+
+	memcpy(opt+2, data, data_len);
+	data_len += 2;
+	opt += data_len;
+	if ((space -= data_len) > 0)
+		memset(opt, 0, space);
+	return opt + space;
+}
+
+static struct nd_opt_hdr *ndisc_next_option(struct nd_opt_hdr *cur,
+					    struct nd_opt_hdr *end)
+{
+	int type;
+	if (!cur || !end || cur >= end)
+		return NULL;
+	type = cur->nd_opt_type;
+	do {
+		cur = ((void *)cur) + (cur->nd_opt_len << 3);
+	} while(cur < end && cur->nd_opt_type != type);
+	return (cur <= end && cur->nd_opt_type == type ? cur : NULL);
+}
+
+static struct ndisc_options *ndisc_parse_options(u8 *opt, int opt_len,
+						 struct ndisc_options *ndopts)
+{
+	struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)opt;
+
+	if (!nd_opt || opt_len < 0 || !ndopts)
+		return NULL;
+	memset(ndopts, 0, sizeof(*ndopts));
+	while (opt_len) {
+		int l;
+		if (opt_len < sizeof(struct nd_opt_hdr))
+			return NULL;
+		l = nd_opt->nd_opt_len << 3;
+		if (opt_len < l || l == 0)
+			return NULL;
+		switch (nd_opt->nd_opt_type) {
+		case ND_OPT_SOURCE_LL_ADDR:
+		case ND_OPT_TARGET_LL_ADDR:
+		case ND_OPT_MTU:
+		case ND_OPT_REDIRECT_HDR:
+			if (ndopts->nd_opt_array[nd_opt->nd_opt_type]) {
+				ND_PRINTK2(KERN_WARNING
+					   "%s(): duplicated ND6 option found: type=%d\n",
+					   __FUNCTION__,
+					   nd_opt->nd_opt_type);
+			} else {
+				ndopts->nd_opt_array[nd_opt->nd_opt_type] = nd_opt;
+			}
+			break;
+		case ND_OPT_PREFIX_INFO:
+			ndopts->nd_opts_pi_end = nd_opt;
+			if (ndopts->nd_opt_array[nd_opt->nd_opt_type] == 0)
+				ndopts->nd_opt_array[nd_opt->nd_opt_type] = nd_opt;
+			break;
+		default:
+			/*
+			 * Unknown options must be silently ignored,
+			 * to accommodate future extension to the protocol.
+			 */
+			ND_PRINTK2(KERN_NOTICE
+				   "%s(): ignored unsupported option; type=%d, len=%d\n",
+				   __FUNCTION__,
+				   nd_opt->nd_opt_type, nd_opt->nd_opt_len);
+		}
+		opt_len -= l;
+		nd_opt = ((void *)nd_opt) + l;
+	}
+	return ndopts;
+}
+
+static inline u8 *ndisc_opt_addr_data(struct nd_opt_hdr *p,
+				      struct net_device *dev)
+{
+	u8 *lladdr = (u8 *)(p + 1);
+	int lladdrlen = p->nd_opt_len << 3;
+	int prepad = ndisc_addr_option_pad(dev->type);
+	if (lladdrlen != NDISC_OPT_SPACE(dev->addr_len + prepad))
+		return NULL;
+	return (lladdr + prepad);
+}
+
+int ndisc_mc_map(struct in6_addr *addr, char *buf, struct net_device *dev, int dir)
+{
+	switch (dev->type) {
+	case ARPHRD_ETHER:
+	case ARPHRD_IEEE802:	/* Not sure. Check it later. --ANK */
+	case ARPHRD_FDDI:
+		ipv6_eth_mc_map(addr, buf);
+		return 0;
+	case ARPHRD_IEEE802_TR:
+		ipv6_tr_mc_map(addr,buf);
+		return 0;
+	case ARPHRD_ARCNET:
+		ipv6_arcnet_mc_map(addr, buf);
+		return 0;
+	case ARPHRD_INFINIBAND:
+		ipv6_ib_mc_map(addr, buf);
+		return 0;
+	default:
+		if (dir) {
+			memcpy(buf, dev->broadcast, dev->addr_len);
+			return 0;
+		}
+	}
+	return -EINVAL;
+}
+
+static u32 ndisc_hash(const void *pkey, const struct net_device *dev)
+{
+	const u32 *p32 = pkey;
+	u32 addr_hash, i;
+
+	addr_hash = 0;
+	for (i = 0; i < (sizeof(struct in6_addr) / sizeof(u32)); i++)
+		addr_hash ^= *p32++;
+
+	return jhash_2words(addr_hash, dev->ifindex, nd_tbl.hash_rnd);
+}
+
+static int ndisc_constructor(struct neighbour *neigh)
+{
+	struct in6_addr *addr = (struct in6_addr*)&neigh->primary_key;
+	struct net_device *dev = neigh->dev;
+	struct inet6_dev *in6_dev;
+	struct neigh_parms *parms;
+	int is_multicast = ipv6_addr_is_multicast(addr);
+
+	rcu_read_lock();
+	in6_dev = in6_dev_get(dev);
+	if (in6_dev == NULL) {
+		rcu_read_unlock();
+		return -EINVAL;
+	}
+
+	parms = in6_dev->nd_parms;
+	__neigh_parms_put(neigh->parms);
+	neigh->parms = neigh_parms_clone(parms);
+	rcu_read_unlock();
+
+	neigh->type = is_multicast ? RTN_MULTICAST : RTN_UNICAST;
+	if (dev->hard_header == NULL) {
+		neigh->nud_state = NUD_NOARP;
+		neigh->ops = &ndisc_direct_ops;
+		neigh->output = neigh->ops->queue_xmit;
+	} else {
+		if (is_multicast) {
+			neigh->nud_state = NUD_NOARP;
+			ndisc_mc_map(addr, neigh->ha, dev, 1);
+		} else if (dev->flags&(IFF_NOARP|IFF_LOOPBACK)) {
+			neigh->nud_state = NUD_NOARP;
+			memcpy(neigh->ha, dev->dev_addr, dev->addr_len);
+			if (dev->flags&IFF_LOOPBACK)
+				neigh->type = RTN_LOCAL;
+		} else if (dev->flags&IFF_POINTOPOINT) {
+			neigh->nud_state = NUD_NOARP;
+			memcpy(neigh->ha, dev->broadcast, dev->addr_len);
+		}
+		if (dev->hard_header_cache)
+			neigh->ops = &ndisc_hh_ops;
+		else
+			neigh->ops = &ndisc_generic_ops;
+		if (neigh->nud_state&NUD_VALID)
+			neigh->output = neigh->ops->connected_output;
+		else
+			neigh->output = neigh->ops->output;
+	}
+	in6_dev_put(in6_dev);
+	return 0;
+}
+
+static int pndisc_constructor(struct pneigh_entry *n)
+{
+	struct in6_addr *addr = (struct in6_addr*)&n->key;
+	struct in6_addr maddr;
+	struct net_device *dev = n->dev;
+
+	if (dev == NULL || __in6_dev_get(dev) == NULL)
+		return -EINVAL;
+	addrconf_addr_solict_mult(addr, &maddr);
+	ipv6_dev_mc_inc(dev, &maddr);
+	return 0;
+}
+
+static void pndisc_destructor(struct pneigh_entry *n)
+{
+	struct in6_addr *addr = (struct in6_addr*)&n->key;
+	struct in6_addr maddr;
+	struct net_device *dev = n->dev;
+
+	if (dev == NULL || __in6_dev_get(dev) == NULL)
+		return;
+	addrconf_addr_solict_mult(addr, &maddr);
+	ipv6_dev_mc_dec(dev, &maddr);
+}
+
+/*
+ *	Send a Neighbour Advertisement
+ */
+
+static inline void ndisc_flow_init(struct flowi *fl, u8 type,
+			    struct in6_addr *saddr, struct in6_addr *daddr)
+{
+	memset(fl, 0, sizeof(*fl));
+	ipv6_addr_copy(&fl->fl6_src, saddr);
+	ipv6_addr_copy(&fl->fl6_dst, daddr);
+	fl->proto	 	= IPPROTO_ICMPV6;
+	fl->fl_icmp_type	= type;
+	fl->fl_icmp_code	= 0;
+}
+
+static void ndisc_send_na(struct net_device *dev, struct neighbour *neigh,
+		   struct in6_addr *daddr, struct in6_addr *solicited_addr,
+	 	   int router, int solicited, int override, int inc_opt) 
+{
+	struct in6_addr tmpaddr;
+	struct inet6_ifaddr *ifp;
+	struct inet6_dev *idev;
+	struct flowi fl;
+	struct dst_entry* dst;
+        struct sock *sk = ndisc_socket->sk;
+	struct in6_addr *src_addr;
+        struct nd_msg *msg;
+        int len;
+        struct sk_buff *skb;
+	int err;
+
+	len = sizeof(struct icmp6hdr) + sizeof(struct in6_addr);
+
+	/* for anycast or proxy, solicited_addr != src_addr */
+	ifp = ipv6_get_ifaddr(solicited_addr, dev, 1);
+ 	if (ifp) {
+		src_addr = solicited_addr;
+		in6_ifa_put(ifp);
+	} else {
+		if (ipv6_dev_get_saddr(dev, daddr, &tmpaddr))
+			return;
+		src_addr = &tmpaddr;
+	}
+
+	ndisc_flow_init(&fl, NDISC_NEIGHBOUR_ADVERTISEMENT, src_addr, daddr);
+
+	dst = ndisc_dst_alloc(dev, neigh, daddr, ip6_output);
+	if (!dst)
+		return;
+
+	err = xfrm_lookup(&dst, &fl, NULL, 0);
+	if (err < 0) {
+		dst_release(dst);
+		return;
+	}
+
+	if (inc_opt) {
+		if (dev->addr_len)
+			len += ndisc_opt_addr_space(dev);
+		else
+			inc_opt = 0;
+	}
+
+	skb = sock_alloc_send_skb(sk, MAX_HEADER + len + LL_RESERVED_SPACE(dev),
+				  1, &err);
+
+	if (skb == NULL) {
+		ND_PRINTK0(KERN_ERR
+			   "ICMPv6 NA: %s() failed to allocate an skb.\n", 
+			   __FUNCTION__);
+		dst_release(dst);
+		return;
+	}
+
+	skb_reserve(skb, LL_RESERVED_SPACE(dev));
+	ip6_nd_hdr(sk, skb, dev, src_addr, daddr, IPPROTO_ICMPV6, len);
+
+	msg = (struct nd_msg *)skb_put(skb, len);
+	skb->h.raw = (unsigned char*)msg;
+
+        msg->icmph.icmp6_type = NDISC_NEIGHBOUR_ADVERTISEMENT;
+        msg->icmph.icmp6_code = 0;
+        msg->icmph.icmp6_cksum = 0;
+
+        msg->icmph.icmp6_unused = 0;
+        msg->icmph.icmp6_router    = router;
+        msg->icmph.icmp6_solicited = solicited;
+        msg->icmph.icmp6_override  = !!override;
+
+        /* Set the target address. */
+	ipv6_addr_copy(&msg->target, solicited_addr);
+
+	if (inc_opt)
+		ndisc_fill_addr_option(msg->opt, ND_OPT_TARGET_LL_ADDR, dev->dev_addr,
+				       dev->addr_len, dev->type);
+
+	/* checksum */
+	msg->icmph.icmp6_cksum = csum_ipv6_magic(src_addr, daddr, len, 
+						 IPPROTO_ICMPV6,
+						 csum_partial((__u8 *) msg, 
+							      len, 0));
+
+	skb->dst = dst;
+	idev = in6_dev_get(dst->dev);
+	IP6_INC_STATS(IPSTATS_MIB_OUTREQUESTS);
+	err = NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, skb, NULL, dst->dev, dst_output);
+	if (!err) {
+		ICMP6_INC_STATS(idev, ICMP6_MIB_OUTNEIGHBORADVERTISEMENTS);
+		ICMP6_INC_STATS(idev, ICMP6_MIB_OUTMSGS);
+	}
+
+	if (likely(idev != NULL))
+		in6_dev_put(idev);
+}        
+
+void ndisc_send_ns(struct net_device *dev, struct neighbour *neigh,
+		   struct in6_addr *solicit,
+		   struct in6_addr *daddr, struct in6_addr *saddr) 
+{
+	struct flowi fl;
+	struct dst_entry* dst;
+	struct inet6_dev *idev;
+        struct sock *sk = ndisc_socket->sk;
+        struct sk_buff *skb;
+        struct nd_msg *msg;
+	struct in6_addr addr_buf;
+        int len;
+	int err;
+	int send_llinfo;
+
+	if (saddr == NULL) {
+		if (ipv6_get_lladdr(dev, &addr_buf))
+			return;
+		saddr = &addr_buf;
+	}
+
+	ndisc_flow_init(&fl, NDISC_NEIGHBOUR_SOLICITATION, saddr, daddr);
+
+	dst = ndisc_dst_alloc(dev, neigh, daddr, ip6_output);
+	if (!dst)
+		return;
+
+	err = xfrm_lookup(&dst, &fl, NULL, 0);
+	if (err < 0) {
+		dst_release(dst);
+		return;
+	}
+
+	len = sizeof(struct icmp6hdr) + sizeof(struct in6_addr);
+	send_llinfo = dev->addr_len && !ipv6_addr_any(saddr);
+	if (send_llinfo)
+		len += ndisc_opt_addr_space(dev);
+
+	skb = sock_alloc_send_skb(sk, MAX_HEADER + len + LL_RESERVED_SPACE(dev),
+				  1, &err);
+	if (skb == NULL) {
+		ND_PRINTK0(KERN_ERR
+			   "ICMPv6 NA: %s() failed to allocate an skb.\n", 
+			   __FUNCTION__);
+		dst_release(dst);
+		return;
+	}
+
+	skb_reserve(skb, LL_RESERVED_SPACE(dev));
+	ip6_nd_hdr(sk, skb, dev, saddr, daddr, IPPROTO_ICMPV6, len);
+
+	msg = (struct nd_msg *)skb_put(skb, len);
+	skb->h.raw = (unsigned char*)msg;
+	msg->icmph.icmp6_type = NDISC_NEIGHBOUR_SOLICITATION;
+	msg->icmph.icmp6_code = 0;
+	msg->icmph.icmp6_cksum = 0;
+	msg->icmph.icmp6_unused = 0;
+
+	/* Set the target address. */
+	ipv6_addr_copy(&msg->target, solicit);
+
+	if (send_llinfo)
+		ndisc_fill_addr_option(msg->opt, ND_OPT_SOURCE_LL_ADDR, dev->dev_addr,
+				       dev->addr_len, dev->type);
+
+	/* checksum */
+	msg->icmph.icmp6_cksum = csum_ipv6_magic(&skb->nh.ipv6h->saddr,
+						 daddr, len, 
+						 IPPROTO_ICMPV6,
+						 csum_partial((__u8 *) msg, 
+							      len, 0));
+	/* send it! */
+	skb->dst = dst;
+	idev = in6_dev_get(dst->dev);
+	IP6_INC_STATS(IPSTATS_MIB_OUTREQUESTS);
+	err = NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, skb, NULL, dst->dev, dst_output);
+	if (!err) {
+		ICMP6_INC_STATS(idev, ICMP6_MIB_OUTNEIGHBORSOLICITS);
+		ICMP6_INC_STATS(idev, ICMP6_MIB_OUTMSGS);
+	}
+
+	if (likely(idev != NULL))
+		in6_dev_put(idev);
+}
+
+void ndisc_send_rs(struct net_device *dev, struct in6_addr *saddr,
+		   struct in6_addr *daddr)
+{
+	struct flowi fl;
+	struct dst_entry* dst;
+	struct inet6_dev *idev;
+	struct sock *sk = ndisc_socket->sk;
+        struct sk_buff *skb;
+        struct icmp6hdr *hdr;
+	__u8 * opt;
+        int len;
+	int err;
+
+	ndisc_flow_init(&fl, NDISC_ROUTER_SOLICITATION, saddr, daddr);
+
+	dst = ndisc_dst_alloc(dev, NULL, daddr, ip6_output);
+	if (!dst)
+		return;
+
+	err = xfrm_lookup(&dst, &fl, NULL, 0);
+	if (err < 0) {
+		dst_release(dst);
+		return;
+	}
+
+	len = sizeof(struct icmp6hdr);
+	if (dev->addr_len)
+		len += ndisc_opt_addr_space(dev);
+
+        skb = sock_alloc_send_skb(sk, MAX_HEADER + len + LL_RESERVED_SPACE(dev),
+				  1, &err);
+	if (skb == NULL) {
+		ND_PRINTK0(KERN_ERR
+			   "ICMPv6 RS: %s() failed to allocate an skb.\n", 
+			   __FUNCTION__);
+		dst_release(dst);
+		return;
+	}
+
+	skb_reserve(skb, LL_RESERVED_SPACE(dev));
+	ip6_nd_hdr(sk, skb, dev, saddr, daddr, IPPROTO_ICMPV6, len);
+
+        hdr = (struct icmp6hdr *)skb_put(skb, len);
+        skb->h.raw = (unsigned char*)hdr;
+        hdr->icmp6_type = NDISC_ROUTER_SOLICITATION;
+        hdr->icmp6_code = 0;
+        hdr->icmp6_cksum = 0;
+        hdr->icmp6_unused = 0;
+
+	opt = (u8*) (hdr + 1);
+
+	if (dev->addr_len)
+		ndisc_fill_addr_option(opt, ND_OPT_SOURCE_LL_ADDR, dev->dev_addr,
+				       dev->addr_len, dev->type);
+
+	/* checksum */
+	hdr->icmp6_cksum = csum_ipv6_magic(&skb->nh.ipv6h->saddr, daddr, len,
+					   IPPROTO_ICMPV6,
+					   csum_partial((__u8 *) hdr, len, 0));
+
+	/* send it! */
+	skb->dst = dst;
+	idev = in6_dev_get(dst->dev);
+	IP6_INC_STATS(IPSTATS_MIB_OUTREQUESTS);	
+	err = NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, skb, NULL, dst->dev, dst_output);
+	if (!err) {
+		ICMP6_INC_STATS(idev, ICMP6_MIB_OUTROUTERSOLICITS);
+		ICMP6_INC_STATS(idev, ICMP6_MIB_OUTMSGS);
+	}
+
+	if (likely(idev != NULL))
+		in6_dev_put(idev);
+}
+		   
+
+static void ndisc_error_report(struct neighbour *neigh, struct sk_buff *skb)
+{
+	/*
+	 *	"The sender MUST return an ICMP
+	 *	 destination unreachable"
+	 */
+	dst_link_failure(skb);
+	kfree_skb(skb);
+}
+
+/* Called with locked neigh: either read or both */
+
+static void ndisc_solicit(struct neighbour *neigh, struct sk_buff *skb)
+{
+	struct in6_addr *saddr = NULL;
+	struct in6_addr mcaddr;
+	struct net_device *dev = neigh->dev;
+	struct in6_addr *target = (struct in6_addr *)&neigh->primary_key;
+	int probes = atomic_read(&neigh->probes);
+
+	if (skb && ipv6_chk_addr(&skb->nh.ipv6h->saddr, dev, 1))
+		saddr = &skb->nh.ipv6h->saddr;
+
+	if ((probes -= neigh->parms->ucast_probes) < 0) {
+		if (!(neigh->nud_state & NUD_VALID)) {
+			ND_PRINTK1(KERN_DEBUG
+				   "%s(): trying to ucast probe in NUD_INVALID: "
+				   "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
+				   __FUNCTION__,
+				   NIP6(*target));
+		}
+		ndisc_send_ns(dev, neigh, target, target, saddr);
+	} else if ((probes -= neigh->parms->app_probes) < 0) {
+#ifdef CONFIG_ARPD
+		neigh_app_ns(neigh);
+#endif
+	} else {
+		addrconf_addr_solict_mult(target, &mcaddr);
+		ndisc_send_ns(dev, NULL, target, &mcaddr, saddr);
+	}
+}
+
+static void ndisc_recv_ns(struct sk_buff *skb)
+{
+	struct nd_msg *msg = (struct nd_msg *)skb->h.raw;
+	struct in6_addr *saddr = &skb->nh.ipv6h->saddr;
+	struct in6_addr *daddr = &skb->nh.ipv6h->daddr;
+	u8 *lladdr = NULL;
+	u32 ndoptlen = skb->tail - msg->opt;
+	struct ndisc_options ndopts;
+	struct net_device *dev = skb->dev;
+	struct inet6_ifaddr *ifp;
+	struct inet6_dev *idev = NULL;
+	struct neighbour *neigh;
+	int dad = ipv6_addr_any(saddr);
+	int inc;
+
+	if (ipv6_addr_is_multicast(&msg->target)) {
+		ND_PRINTK2(KERN_WARNING 
+			   "ICMPv6 NS: multicast target address");
+		return;
+	}
+
+	/*
+	 * RFC2461 7.1.1:
+	 * DAD has to be destined for solicited node multicast address.
+	 */
+	if (dad &&
+	    !(daddr->s6_addr32[0] == htonl(0xff020000) &&
+	      daddr->s6_addr32[1] == htonl(0x00000000) &&
+	      daddr->s6_addr32[2] == htonl(0x00000001) &&
+	      daddr->s6_addr [12] == 0xff )) {
+		ND_PRINTK2(KERN_WARNING
+			   "ICMPv6 NS: bad DAD packet (wrong destination)\n");
+		return;
+	}
+
+	if (!ndisc_parse_options(msg->opt, ndoptlen, &ndopts)) {
+		ND_PRINTK2(KERN_WARNING 
+			   "ICMPv6 NS: invalid ND options\n");
+		return;
+	}
+
+	if (ndopts.nd_opts_src_lladdr) {
+		lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr, dev);
+		if (!lladdr) {
+			ND_PRINTK2(KERN_WARNING
+				   "ICMPv6 NS: invalid link-layer address length\n");
+			return;
+		}
+
+		/* RFC2461 7.1.1:
+	 	 *	If the IP source address is the unspecified address, 
+		 *	there MUST NOT be source link-layer address option 
+		 *	in the message.
+		 */
+		if (dad) {
+			ND_PRINTK2(KERN_WARNING 
+				   "ICMPv6 NS: bad DAD packet (link-layer address option)\n");
+			return;
+		}
+	}
+
+	inc = ipv6_addr_is_multicast(daddr);
+
+	if ((ifp = ipv6_get_ifaddr(&msg->target, dev, 1)) != NULL) {
+		if (ifp->flags & IFA_F_TENTATIVE) {
+			/* Address is tentative. If the source
+			   is unspecified address, it is someone
+			   does DAD, otherwise we ignore solicitations
+			   until DAD timer expires.
+			 */
+			if (!dad)
+				goto out;
+			if (dev->type == ARPHRD_IEEE802_TR) {
+				unsigned char *sadr = skb->mac.raw;
+				if (((sadr[8] ^ dev->dev_addr[0]) & 0x7f) == 0 &&
+				    sadr[9] == dev->dev_addr[1] &&
+				    sadr[10] == dev->dev_addr[2] &&
+				    sadr[11] == dev->dev_addr[3] &&
+				    sadr[12] == dev->dev_addr[4] &&
+				    sadr[13] == dev->dev_addr[5]) {
+					/* looped-back to us */
+					goto out;
+				}
+			}
+			addrconf_dad_failure(ifp); 
+			return;
+		}
+
+		idev = ifp->idev;
+	} else {
+		idev = in6_dev_get(dev);
+		if (!idev) {
+			/* XXX: count this drop? */
+			return;
+		}
+
+		if (ipv6_chk_acast_addr(dev, &msg->target) ||
+		    (idev->cnf.forwarding && 
+		     pneigh_lookup(&nd_tbl, &msg->target, dev, 0))) {
+			if (skb->stamp.tv_sec != LOCALLY_ENQUEUED &&
+			    skb->pkt_type != PACKET_HOST &&
+			    inc != 0 &&
+			    idev->nd_parms->proxy_delay != 0) {
+				/*
+				 * for anycast or proxy,
+				 * sender should delay its response 
+				 * by a random time between 0 and 
+				 * MAX_ANYCAST_DELAY_TIME seconds.
+				 * (RFC2461) -- yoshfuji
+				 */
+				struct sk_buff *n = skb_clone(skb, GFP_ATOMIC);
+				if (n)
+					pneigh_enqueue(&nd_tbl, idev->nd_parms, n);
+				goto out;
+			}
+		} else
+			goto out;
+	}
+
+	if (dad) {
+		struct in6_addr maddr;
+
+		ipv6_addr_all_nodes(&maddr);
+		ndisc_send_na(dev, NULL, &maddr, &msg->target,
+			      idev->cnf.forwarding, 0, (ifp != NULL), 1);
+		goto out;
+	}
+
+	if (inc)
+		NEIGH_CACHE_STAT_INC(&nd_tbl, rcv_probes_mcast);
+	else
+		NEIGH_CACHE_STAT_INC(&nd_tbl, rcv_probes_ucast);
+
+	/* 
+	 *	update / create cache entry
+	 *	for the source address
+	 */
+	neigh = __neigh_lookup(&nd_tbl, saddr, dev,
+			       !inc || lladdr || !dev->addr_len);
+	if (neigh)
+		neigh_update(neigh, lladdr, NUD_STALE, 
+			     NEIGH_UPDATE_F_WEAK_OVERRIDE|
+			     NEIGH_UPDATE_F_OVERRIDE);
+	if (neigh || !dev->hard_header) {
+		ndisc_send_na(dev, neigh, saddr, &msg->target,
+			      idev->cnf.forwarding, 
+			      1, (ifp != NULL && inc), inc);
+		if (neigh)
+			neigh_release(neigh);
+	}
+
+out:
+	if (ifp)
+		in6_ifa_put(ifp);
+	else
+		in6_dev_put(idev);
+
+	return;
+}
+
+static void ndisc_recv_na(struct sk_buff *skb)
+{
+	struct nd_msg *msg = (struct nd_msg *)skb->h.raw;
+	struct in6_addr *saddr = &skb->nh.ipv6h->saddr;
+	struct in6_addr *daddr = &skb->nh.ipv6h->daddr;
+	u8 *lladdr = NULL;
+	u32 ndoptlen = skb->tail - msg->opt;
+	struct ndisc_options ndopts;
+	struct net_device *dev = skb->dev;
+	struct inet6_ifaddr *ifp;
+	struct neighbour *neigh;
+
+	if (skb->len < sizeof(struct nd_msg)) {
+		ND_PRINTK2(KERN_WARNING
+			   "ICMPv6 NA: packet too short\n");
+		return;
+	}
+
+	if (ipv6_addr_is_multicast(&msg->target)) {
+		ND_PRINTK2(KERN_WARNING
+			   "ICMPv6 NA: target address is multicast.\n");
+		return;
+	}
+
+	if (ipv6_addr_is_multicast(daddr) &&
+	    msg->icmph.icmp6_solicited) {
+		ND_PRINTK2(KERN_WARNING
+			   "ICMPv6 NA: solicited NA is multicasted.\n");
+		return;
+	}
+		
+	if (!ndisc_parse_options(msg->opt, ndoptlen, &ndopts)) {
+		ND_PRINTK2(KERN_WARNING
+			   "ICMPv6 NS: invalid ND option\n");
+		return;
+	}
+	if (ndopts.nd_opts_tgt_lladdr) {
+		lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr, dev);
+		if (!lladdr) {
+			ND_PRINTK2(KERN_WARNING
+				   "ICMPv6 NA: invalid link-layer address length\n");
+			return;
+		}
+	}
+	if ((ifp = ipv6_get_ifaddr(&msg->target, dev, 1))) {
+		if (ifp->flags & IFA_F_TENTATIVE) {
+			addrconf_dad_failure(ifp);
+			return;
+		}
+		/* What should we make now? The advertisement
+		   is invalid, but ndisc specs say nothing
+		   about it. It could be misconfiguration, or
+		   an smart proxy agent tries to help us :-)
+		 */
+		ND_PRINTK1(KERN_WARNING
+			   "ICMPv6 NA: someone advertises our address on %s!\n",
+			   ifp->idev->dev->name);
+		in6_ifa_put(ifp);
+		return;
+	}
+	neigh = neigh_lookup(&nd_tbl, &msg->target, dev);
+
+	if (neigh) {
+		u8 old_flags = neigh->flags;
+
+		if (neigh->nud_state & NUD_FAILED)
+			goto out;
+
+		neigh_update(neigh, lladdr,
+			     msg->icmph.icmp6_solicited ? NUD_REACHABLE : NUD_STALE,
+			     NEIGH_UPDATE_F_WEAK_OVERRIDE|
+			     (msg->icmph.icmp6_override ? NEIGH_UPDATE_F_OVERRIDE : 0)|
+			     NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
+			     (msg->icmph.icmp6_router ? NEIGH_UPDATE_F_ISROUTER : 0));
+
+		if ((old_flags & ~neigh->flags) & NTF_ROUTER) {
+			/*
+			 * Change: router to host
+			 */
+			struct rt6_info *rt;
+			rt = rt6_get_dflt_router(saddr, dev);
+			if (rt)
+				ip6_del_rt(rt, NULL, NULL);
+		}
+
+out:
+		neigh_release(neigh);
+	}
+}
+
+static void ndisc_recv_rs(struct sk_buff *skb)
+{
+	struct rs_msg *rs_msg = (struct rs_msg *) skb->h.raw;
+	unsigned long ndoptlen = skb->len - sizeof(*rs_msg);
+	struct neighbour *neigh;
+	struct inet6_dev *idev;
+	struct in6_addr *saddr = &skb->nh.ipv6h->saddr;
+	struct ndisc_options ndopts;
+	u8 *lladdr = NULL;
+
+	if (skb->len < sizeof(*rs_msg))
+		return;
+
+	idev = in6_dev_get(skb->dev);
+	if (!idev) {
+		if (net_ratelimit())
+			ND_PRINTK1("ICMP6 RS: can't find in6 device\n");
+		return;
+	}
+
+	/* Don't accept RS if we're not in router mode */
+	if (!idev->cnf.forwarding)
+		goto out;
+
+	/*
+	 * Don't update NCE if src = ::;
+	 * this implies that the source node has no ip address assigned yet.
+	 */
+	if (ipv6_addr_any(saddr))
+		goto out;
+
+	/* Parse ND options */
+	if (!ndisc_parse_options(rs_msg->opt, ndoptlen, &ndopts)) {
+		if (net_ratelimit())
+			ND_PRINTK2("ICMP6 NS: invalid ND option, ignored\n");
+		goto out;
+	}
+
+	if (ndopts.nd_opts_src_lladdr) {
+		lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr,
+					     skb->dev);
+		if (!lladdr)
+			goto out;
+	}
+
+	neigh = __neigh_lookup(&nd_tbl, saddr, skb->dev, 1);
+	if (neigh) {
+		neigh_update(neigh, lladdr, NUD_STALE,
+			     NEIGH_UPDATE_F_WEAK_OVERRIDE|
+			     NEIGH_UPDATE_F_OVERRIDE|
+			     NEIGH_UPDATE_F_OVERRIDE_ISROUTER);
+		neigh_release(neigh);
+	}
+out:
+	in6_dev_put(idev);
+}
+
+static void ndisc_router_discovery(struct sk_buff *skb)
+{
+        struct ra_msg *ra_msg = (struct ra_msg *) skb->h.raw;
+	struct neighbour *neigh = NULL;
+	struct inet6_dev *in6_dev;
+	struct rt6_info *rt;
+	int lifetime;
+	struct ndisc_options ndopts;
+	int optlen;
+
+	__u8 * opt = (__u8 *)(ra_msg + 1);
+
+	optlen = (skb->tail - skb->h.raw) - sizeof(struct ra_msg);
+
+	if (!(ipv6_addr_type(&skb->nh.ipv6h->saddr) & IPV6_ADDR_LINKLOCAL)) {
+		ND_PRINTK2(KERN_WARNING
+			   "ICMPv6 RA: source address is not link-local.\n");
+		return;
+	}
+	if (optlen < 0) {
+		ND_PRINTK2(KERN_WARNING 
+			   "ICMPv6 RA: packet too short\n");
+		return;
+	}
+
+	/*
+	 *	set the RA_RECV flag in the interface
+	 */
+
+	in6_dev = in6_dev_get(skb->dev);
+	if (in6_dev == NULL) {
+		ND_PRINTK0(KERN_ERR
+			   "ICMPv6 RA: can't find inet6 device for %s.\n",
+			   skb->dev->name);
+		return;
+	}
+	if (in6_dev->cnf.forwarding || !in6_dev->cnf.accept_ra) {
+		in6_dev_put(in6_dev);
+		return;
+	}
+
+	if (!ndisc_parse_options(opt, optlen, &ndopts)) {
+		in6_dev_put(in6_dev);
+		ND_PRINTK2(KERN_WARNING
+			   "ICMP6 RA: invalid ND options\n");
+		return;
+	}
+
+	if (in6_dev->if_flags & IF_RS_SENT) {
+		/*
+		 *	flag that an RA was received after an RS was sent
+		 *	out on this interface.
+		 */
+		in6_dev->if_flags |= IF_RA_RCVD;
+	}
+
+	/*
+	 * Remember the managed/otherconf flags from most recently
+	 * received RA message (RFC 2462) -- yoshfuji
+	 */
+	in6_dev->if_flags = (in6_dev->if_flags & ~(IF_RA_MANAGED |
+				IF_RA_OTHERCONF)) |
+				(ra_msg->icmph.icmp6_addrconf_managed ?
+					IF_RA_MANAGED : 0) |
+				(ra_msg->icmph.icmp6_addrconf_other ?
+					IF_RA_OTHERCONF : 0);
+
+	lifetime = ntohs(ra_msg->icmph.icmp6_rt_lifetime);
+
+	rt = rt6_get_dflt_router(&skb->nh.ipv6h->saddr, skb->dev);
+
+	if (rt)
+		neigh = rt->rt6i_nexthop;
+
+	if (rt && lifetime == 0) {
+		neigh_clone(neigh);
+		ip6_del_rt(rt, NULL, NULL);
+		rt = NULL;
+	}
+
+	if (rt == NULL && lifetime) {
+		ND_PRINTK3(KERN_DEBUG
+			   "ICMPv6 RA: adding default router.\n");
+
+		rt = rt6_add_dflt_router(&skb->nh.ipv6h->saddr, skb->dev);
+		if (rt == NULL) {
+			ND_PRINTK0(KERN_ERR
+				   "ICMPv6 RA: %s() failed to add default route.\n",
+				   __FUNCTION__);
+			in6_dev_put(in6_dev);
+			return;
+		}
+
+		neigh = rt->rt6i_nexthop;
+		if (neigh == NULL) {
+			ND_PRINTK0(KERN_ERR
+				   "ICMPv6 RA: %s() got default router without neighbour.\n",
+				   __FUNCTION__);
+			dst_release(&rt->u.dst);
+			in6_dev_put(in6_dev);
+			return;
+		}
+		neigh->flags |= NTF_ROUTER;
+	}
+
+	if (rt)
+		rt->rt6i_expires = jiffies + (HZ * lifetime);
+
+	if (ra_msg->icmph.icmp6_hop_limit) {
+		in6_dev->cnf.hop_limit = ra_msg->icmph.icmp6_hop_limit;
+		if (rt)
+			rt->u.dst.metrics[RTAX_HOPLIMIT-1] = ra_msg->icmph.icmp6_hop_limit;
+	}
+
+	/*
+	 *	Update Reachable Time and Retrans Timer
+	 */
+
+	if (in6_dev->nd_parms) {
+		unsigned long rtime = ntohl(ra_msg->retrans_timer);
+
+		if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/HZ) {
+			rtime = (rtime*HZ)/1000;
+			if (rtime < HZ/10)
+				rtime = HZ/10;
+			in6_dev->nd_parms->retrans_time = rtime;
+			in6_dev->tstamp = jiffies;
+			inet6_ifinfo_notify(RTM_NEWLINK, in6_dev);
+		}
+
+		rtime = ntohl(ra_msg->reachable_time);
+		if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/(3*HZ)) {
+			rtime = (rtime*HZ)/1000;
+
+			if (rtime < HZ/10)
+				rtime = HZ/10;
+
+			if (rtime != in6_dev->nd_parms->base_reachable_time) {
+				in6_dev->nd_parms->base_reachable_time = rtime;
+				in6_dev->nd_parms->gc_staletime = 3 * rtime;
+				in6_dev->nd_parms->reachable_time = neigh_rand_reach_time(rtime);
+				in6_dev->tstamp = jiffies;
+				inet6_ifinfo_notify(RTM_NEWLINK, in6_dev);
+			}
+		}
+	}
+
+	/*
+	 *	Process options.
+	 */
+
+	if (!neigh)
+		neigh = __neigh_lookup(&nd_tbl, &skb->nh.ipv6h->saddr,
+				       skb->dev, 1);
+	if (neigh) {
+		u8 *lladdr = NULL;
+		if (ndopts.nd_opts_src_lladdr) {
+			lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr,
+						     skb->dev);
+			if (!lladdr) {
+				ND_PRINTK2(KERN_WARNING
+					   "ICMPv6 RA: invalid link-layer address length\n");
+				goto out;
+			}
+		}
+		neigh_update(neigh, lladdr, NUD_STALE,
+			     NEIGH_UPDATE_F_WEAK_OVERRIDE|
+			     NEIGH_UPDATE_F_OVERRIDE|
+			     NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
+			     NEIGH_UPDATE_F_ISROUTER);
+	}
+
+	if (ndopts.nd_opts_pi) {
+		struct nd_opt_hdr *p;
+		for (p = ndopts.nd_opts_pi;
+		     p;
+		     p = ndisc_next_option(p, ndopts.nd_opts_pi_end)) {
+			addrconf_prefix_rcv(skb->dev, (u8*)p, (p->nd_opt_len) << 3);
+		}
+	}
+
+	if (ndopts.nd_opts_mtu) {
+		u32 mtu;
+
+		memcpy(&mtu, ((u8*)(ndopts.nd_opts_mtu+1))+2, sizeof(mtu));
+		mtu = ntohl(mtu);
+
+		if (mtu < IPV6_MIN_MTU || mtu > skb->dev->mtu) {
+			ND_PRINTK2(KERN_WARNING
+				   "ICMPv6 RA: invalid mtu: %d\n",
+				   mtu);
+		} else if (in6_dev->cnf.mtu6 != mtu) {
+			in6_dev->cnf.mtu6 = mtu;
+
+			if (rt)
+				rt->u.dst.metrics[RTAX_MTU-1] = mtu;
+
+			rt6_mtu_change(skb->dev, mtu);
+		}
+	}
+			
+	if (ndopts.nd_opts_tgt_lladdr || ndopts.nd_opts_rh) {
+		ND_PRINTK2(KERN_WARNING
+			   "ICMPv6 RA: invalid RA options");
+	}
+out:
+	if (rt)
+		dst_release(&rt->u.dst);
+	else if (neigh)
+		neigh_release(neigh);
+	in6_dev_put(in6_dev);
+}
+
+static void ndisc_redirect_rcv(struct sk_buff *skb)
+{
+	struct inet6_dev *in6_dev;
+	struct icmp6hdr *icmph;
+	struct in6_addr *dest;
+	struct in6_addr *target;	/* new first hop to destination */
+	struct neighbour *neigh;
+	int on_link = 0;
+	struct ndisc_options ndopts;
+	int optlen;
+	u8 *lladdr = NULL;
+
+	if (!(ipv6_addr_type(&skb->nh.ipv6h->saddr) & IPV6_ADDR_LINKLOCAL)) {
+		ND_PRINTK2(KERN_WARNING
+			   "ICMPv6 Redirect: source address is not link-local.\n");
+		return;
+	}
+
+	optlen = skb->tail - skb->h.raw;
+	optlen -= sizeof(struct icmp6hdr) + 2 * sizeof(struct in6_addr);
+
+	if (optlen < 0) {
+		ND_PRINTK2(KERN_WARNING
+			   "ICMPv6 Redirect: packet too short\n");
+		return;
+	}
+
+	icmph = (struct icmp6hdr *) skb->h.raw;
+	target = (struct in6_addr *) (icmph + 1);
+	dest = target + 1;
+
+	if (ipv6_addr_is_multicast(dest)) {
+		ND_PRINTK2(KERN_WARNING
+			   "ICMPv6 Redirect: destination address is multicast.\n");
+		return;
+	}
+
+	if (ipv6_addr_equal(dest, target)) {
+		on_link = 1;
+	} else if (!(ipv6_addr_type(target) & IPV6_ADDR_LINKLOCAL)) {
+		ND_PRINTK2(KERN_WARNING 
+			   "ICMPv6 Redirect: target address is not link-local.\n");
+		return;
+	}
+
+	in6_dev = in6_dev_get(skb->dev);
+	if (!in6_dev)
+		return;
+	if (in6_dev->cnf.forwarding || !in6_dev->cnf.accept_redirects) {
+		in6_dev_put(in6_dev);
+		return;
+	}
+
+	/* RFC2461 8.1: 
+	 *	The IP source address of the Redirect MUST be the same as the current
+	 *	first-hop router for the specified ICMP Destination Address.
+	 */
+		
+	if (!ndisc_parse_options((u8*)(dest + 1), optlen, &ndopts)) {
+		ND_PRINTK2(KERN_WARNING
+			   "ICMPv6 Redirect: invalid ND options\n");
+		in6_dev_put(in6_dev);
+		return;
+	}
+	if (ndopts.nd_opts_tgt_lladdr) {
+		lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr,
+					     skb->dev);
+		if (!lladdr) {
+			ND_PRINTK2(KERN_WARNING
+				   "ICMPv6 Redirect: invalid link-layer address length\n");
+			in6_dev_put(in6_dev);
+			return;
+		}
+	}
+
+	neigh = __neigh_lookup(&nd_tbl, target, skb->dev, 1);
+	if (neigh) {
+		rt6_redirect(dest, &skb->nh.ipv6h->saddr, neigh, lladdr, 
+			     on_link);
+		neigh_release(neigh);
+	}
+	in6_dev_put(in6_dev);
+}
+
+void ndisc_send_redirect(struct sk_buff *skb, struct neighbour *neigh,
+			 struct in6_addr *target)
+{
+	struct sock *sk = ndisc_socket->sk;
+	int len = sizeof(struct icmp6hdr) + 2 * sizeof(struct in6_addr);
+	struct sk_buff *buff;
+	struct icmp6hdr *icmph;
+	struct in6_addr saddr_buf;
+	struct in6_addr *addrp;
+	struct net_device *dev;
+	struct rt6_info *rt;
+	struct dst_entry *dst;
+	struct inet6_dev *idev;
+	struct flowi fl;
+	u8 *opt;
+	int rd_len;
+	int err;
+	int hlen;
+	u8 ha_buf[MAX_ADDR_LEN], *ha = NULL;
+
+	dev = skb->dev;
+
+	if (ipv6_get_lladdr(dev, &saddr_buf)) {
+		ND_PRINTK2(KERN_WARNING
+			   "ICMPv6 Redirect: no link-local address on %s\n",
+			   dev->name);
+ 		return;
+ 	}
+
+	ndisc_flow_init(&fl, NDISC_REDIRECT, &saddr_buf, &skb->nh.ipv6h->saddr);
+
+	dst = ip6_route_output(NULL, &fl);
+	if (dst == NULL)
+		return;
+
+	err = xfrm_lookup(&dst, &fl, NULL, 0);
+	if (err) {
+		dst_release(dst);
+		return;
+	}
+
+	rt = (struct rt6_info *) dst;
+
+	if (rt->rt6i_flags & RTF_GATEWAY) {
+		ND_PRINTK2(KERN_WARNING
+			   "ICMPv6 Redirect: destination is not a neighbour.\n");
+		dst_release(dst);
+		return;
+	}
+	if (!xrlim_allow(dst, 1*HZ)) {
+		dst_release(dst);
+		return;
+	}
+
+	if (dev->addr_len) {
+		read_lock_bh(&neigh->lock);
+		if (neigh->nud_state & NUD_VALID) {
+			memcpy(ha_buf, neigh->ha, dev->addr_len);
+			read_unlock_bh(&neigh->lock);
+			ha = ha_buf;
+			len += ndisc_opt_addr_space(dev);
+		} else
+			read_unlock_bh(&neigh->lock);
+	}
+
+	rd_len = min_t(unsigned int,
+		     IPV6_MIN_MTU-sizeof(struct ipv6hdr)-len, skb->len + 8);
+	rd_len &= ~0x7;
+	len += rd_len;
+
+	buff = sock_alloc_send_skb(sk, MAX_HEADER + len + LL_RESERVED_SPACE(dev),
+				   1, &err);
+	if (buff == NULL) {
+		ND_PRINTK0(KERN_ERR
+			   "ICMPv6 Redirect: %s() failed to allocate an skb.\n",
+			   __FUNCTION__);
+		dst_release(dst);
+		return;
+	}
+
+	hlen = 0;
+
+	skb_reserve(buff, LL_RESERVED_SPACE(dev));
+	ip6_nd_hdr(sk, buff, dev, &saddr_buf, &skb->nh.ipv6h->saddr,
+		   IPPROTO_ICMPV6, len);
+
+	icmph = (struct icmp6hdr *)skb_put(buff, len);
+	buff->h.raw = (unsigned char*)icmph;
+
+	memset(icmph, 0, sizeof(struct icmp6hdr));
+	icmph->icmp6_type = NDISC_REDIRECT;
+
+	/*
+	 *	copy target and destination addresses
+	 */
+
+	addrp = (struct in6_addr *)(icmph + 1);
+	ipv6_addr_copy(addrp, target);
+	addrp++;
+	ipv6_addr_copy(addrp, &skb->nh.ipv6h->daddr);
+
+	opt = (u8*) (addrp + 1);
+
+	/*
+	 *	include target_address option
+	 */
+
+	if (ha)
+		opt = ndisc_fill_addr_option(opt, ND_OPT_TARGET_LL_ADDR, ha,
+					     dev->addr_len, dev->type);
+
+	/*
+	 *	build redirect option and copy skb over to the new packet.
+	 */
+
+	memset(opt, 0, 8);	
+	*(opt++) = ND_OPT_REDIRECT_HDR;
+	*(opt++) = (rd_len >> 3);
+	opt += 6;
+
+	memcpy(opt, skb->nh.ipv6h, rd_len - 8);
+
+	icmph->icmp6_cksum = csum_ipv6_magic(&saddr_buf, &skb->nh.ipv6h->saddr,
+					     len, IPPROTO_ICMPV6,
+					     csum_partial((u8 *) icmph, len, 0));
+
+	buff->dst = dst;
+	idev = in6_dev_get(dst->dev);
+	IP6_INC_STATS(IPSTATS_MIB_OUTREQUESTS);
+	err = NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, buff, NULL, dst->dev, dst_output);
+	if (!err) {
+		ICMP6_INC_STATS(idev, ICMP6_MIB_OUTREDIRECTS);
+		ICMP6_INC_STATS(idev, ICMP6_MIB_OUTMSGS);
+	}
+
+	if (likely(idev != NULL))
+		in6_dev_put(idev);
+}
+
+static void pndisc_redo(struct sk_buff *skb)
+{
+	ndisc_rcv(skb);
+	kfree_skb(skb);
+}
+
+int ndisc_rcv(struct sk_buff *skb)
+{
+	struct nd_msg *msg;
+
+	if (!pskb_may_pull(skb, skb->len))
+		return 0;
+
+	msg = (struct nd_msg *) skb->h.raw;
+
+	__skb_push(skb, skb->data-skb->h.raw);
+
+	if (skb->nh.ipv6h->hop_limit != 255) {
+		ND_PRINTK2(KERN_WARNING
+			   "ICMPv6 NDISC: invalid hop-limit: %d\n",
+			   skb->nh.ipv6h->hop_limit);
+		return 0;
+	}
+
+	if (msg->icmph.icmp6_code != 0) {
+		ND_PRINTK2(KERN_WARNING 
+			   "ICMPv6 NDISC: invalid ICMPv6 code: %d\n",
+			   msg->icmph.icmp6_code);
+		return 0;
+	}
+
+	switch (msg->icmph.icmp6_type) {
+	case NDISC_NEIGHBOUR_SOLICITATION:
+		ndisc_recv_ns(skb);
+		break;
+
+	case NDISC_NEIGHBOUR_ADVERTISEMENT:
+		ndisc_recv_na(skb);
+		break;
+
+	case NDISC_ROUTER_SOLICITATION:
+		ndisc_recv_rs(skb);
+		break;
+
+	case NDISC_ROUTER_ADVERTISEMENT:
+		ndisc_router_discovery(skb);
+		break;
+
+	case NDISC_REDIRECT:
+		ndisc_redirect_rcv(skb);
+		break;
+	};
+
+	return 0;
+}
+
+static int ndisc_netdev_event(struct notifier_block *this, unsigned long event, void *ptr)
+{
+	struct net_device *dev = ptr;
+
+	switch (event) {
+	case NETDEV_CHANGEADDR:
+		neigh_changeaddr(&nd_tbl, dev);
+		fib6_run_gc(~0UL);
+		break;
+	case NETDEV_DOWN:
+		neigh_ifdown(&nd_tbl, dev);
+		fib6_run_gc(~0UL);
+		break;
+	default:
+		break;
+	}
+
+	return NOTIFY_DONE;
+}
+
+static struct notifier_block ndisc_netdev_notifier = {
+	.notifier_call = ndisc_netdev_event,
+};
+
+#ifdef CONFIG_SYSCTL
+static void ndisc_warn_deprecated_sysctl(struct ctl_table *ctl,
+					 const char *func, const char *dev_name)
+{
+	static char warncomm[TASK_COMM_LEN];
+	static int warned;
+	if (strcmp(warncomm, current->comm) && warned < 5) {
+		strcpy(warncomm, current->comm);
+		printk(KERN_WARNING
+			"process `%s' is using deprecated sysctl (%s) "
+			"net.ipv6.neigh.%s.%s; "
+			"Use net.ipv6.neigh.%s.%s_ms "
+			"instead.\n",
+			warncomm, func,
+			dev_name, ctl->procname,
+			dev_name, ctl->procname);
+		warned++;
+	}
+}
+
+int ndisc_ifinfo_sysctl_change(struct ctl_table *ctl, int write, struct file * filp, void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+	struct net_device *dev = ctl->extra1;
+	struct inet6_dev *idev;
+	int ret;
+
+	if (ctl->ctl_name == NET_NEIGH_RETRANS_TIME ||
+	    ctl->ctl_name == NET_NEIGH_REACHABLE_TIME)
+		ndisc_warn_deprecated_sysctl(ctl, "syscall", dev ? dev->name : "default");
+
+	switch (ctl->ctl_name) {
+	case NET_NEIGH_RETRANS_TIME:
+		ret = proc_dointvec(ctl, write, filp, buffer, lenp, ppos);
+		break;
+	case NET_NEIGH_REACHABLE_TIME:
+		ret = proc_dointvec_jiffies(ctl, write,
+					    filp, buffer, lenp, ppos);
+		break;
+	case NET_NEIGH_RETRANS_TIME_MS:
+	case NET_NEIGH_REACHABLE_TIME_MS:
+		ret = proc_dointvec_ms_jiffies(ctl, write,
+					       filp, buffer, lenp, ppos);
+		break;
+	default:
+		ret = -1;
+	}
+
+	if (write && ret == 0 && dev && (idev = in6_dev_get(dev)) != NULL) {
+		if (ctl->ctl_name == NET_NEIGH_REACHABLE_TIME ||
+		    ctl->ctl_name == NET_NEIGH_REACHABLE_TIME_MS)
+			idev->nd_parms->reachable_time = neigh_rand_reach_time(idev->nd_parms->base_reachable_time);
+		idev->tstamp = jiffies;
+		inet6_ifinfo_notify(RTM_NEWLINK, idev);
+		in6_dev_put(idev);
+	}
+	return ret;
+}
+
+static int ndisc_ifinfo_sysctl_strategy(ctl_table *ctl, int __user *name,
+					int nlen, void __user *oldval,
+					size_t __user *oldlenp,
+					void __user *newval, size_t newlen,
+					void **context)
+{
+	struct net_device *dev = ctl->extra1;
+	struct inet6_dev *idev;
+	int ret;
+
+	if (ctl->ctl_name == NET_NEIGH_RETRANS_TIME ||
+	    ctl->ctl_name == NET_NEIGH_REACHABLE_TIME)
+		ndisc_warn_deprecated_sysctl(ctl, "procfs", dev ? dev->name : "default");
+
+	switch (ctl->ctl_name) {
+	case NET_NEIGH_REACHABLE_TIME:
+		ret = sysctl_jiffies(ctl, name, nlen,
+				     oldval, oldlenp, newval, newlen,
+				     context);
+		break;
+	case NET_NEIGH_RETRANS_TIME_MS:
+	case NET_NEIGH_REACHABLE_TIME_MS:
+		 ret = sysctl_ms_jiffies(ctl, name, nlen,
+					 oldval, oldlenp, newval, newlen,
+					 context);
+		 break;
+	default:
+		ret = 0;
+	}
+
+	if (newval && newlen && ret > 0 &&
+	    dev && (idev = in6_dev_get(dev)) != NULL) {
+		if (ctl->ctl_name == NET_NEIGH_REACHABLE_TIME ||
+		    ctl->ctl_name == NET_NEIGH_REACHABLE_TIME_MS)
+			idev->nd_parms->reachable_time = neigh_rand_reach_time(idev->nd_parms->base_reachable_time);
+		idev->tstamp = jiffies;
+		inet6_ifinfo_notify(RTM_NEWLINK, idev);
+		in6_dev_put(idev);
+	}
+
+	return ret;
+}
+
+#endif
+
+int __init ndisc_init(struct net_proto_family *ops)
+{
+	struct ipv6_pinfo *np;
+	struct sock *sk;
+        int err;
+
+	err = sock_create_kern(PF_INET6, SOCK_RAW, IPPROTO_ICMPV6, &ndisc_socket);
+	if (err < 0) {
+		ND_PRINTK0(KERN_ERR
+			   "ICMPv6 NDISC: Failed to initialize the control socket (err %d).\n", 
+			   err);
+		ndisc_socket = NULL; /* For safety. */
+		return err;
+	}
+
+	sk = ndisc_socket->sk;
+	np = inet6_sk(sk);
+	sk->sk_allocation = GFP_ATOMIC;
+	np->hop_limit = 255;
+	/* Do not loopback ndisc messages */
+	np->mc_loop = 0;
+	sk->sk_prot->unhash(sk);
+
+        /*
+         * Initialize the neighbour table
+         */
+	
+	neigh_table_init(&nd_tbl);
+
+#ifdef CONFIG_SYSCTL
+	neigh_sysctl_register(NULL, &nd_tbl.parms, NET_IPV6, NET_IPV6_NEIGH, 
+			      "ipv6",
+			      &ndisc_ifinfo_sysctl_change,
+			      &ndisc_ifinfo_sysctl_strategy);
+#endif
+
+	register_netdevice_notifier(&ndisc_netdev_notifier);
+	return 0;
+}
+
+void ndisc_cleanup(void)
+{
+#ifdef CONFIG_SYSCTL
+	neigh_sysctl_unregister(&nd_tbl.parms);
+#endif
+	neigh_table_clear(&nd_tbl);
+	sock_release(ndisc_socket);
+	ndisc_socket = NULL; /* For safety. */
+}