diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
new file mode 100644
index 0000000..4760c85
--- /dev/null
+++ b/net/ipv6/tcp_ipv6.c
@@ -0,0 +1,2265 @@
+/*
+ *	TCP over IPv6
+ *	Linux INET6 implementation 
+ *
+ *	Authors:
+ *	Pedro Roque		<roque@di.fc.ul.pt>	
+ *
+ *	$Id: tcp_ipv6.c,v 1.144 2002/02/01 22:01:04 davem Exp $
+ *
+ *	Based on: 
+ *	linux/net/ipv4/tcp.c
+ *	linux/net/ipv4/tcp_input.c
+ *	linux/net/ipv4/tcp_output.c
+ *
+ *	Fixes:
+ *	Hideaki YOSHIFUJI	:	sin6_scope_id support
+ *	YOSHIFUJI Hideaki @USAGI and:	Support IPV6_V6ONLY socket option, which
+ *	Alexey Kuznetsov		allow both IPv4 and IPv6 sockets to bind
+ *					a single port at the same time.
+ *	YOSHIFUJI Hideaki @USAGI:	convert /proc/net/tcp6 to seq_file.
+ *
+ *	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.
+ */
+
+#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/net.h>
+#include <linux/jiffies.h>
+#include <linux/in.h>
+#include <linux/in6.h>
+#include <linux/netdevice.h>
+#include <linux/init.h>
+#include <linux/jhash.h>
+#include <linux/ipsec.h>
+#include <linux/times.h>
+
+#include <linux/ipv6.h>
+#include <linux/icmpv6.h>
+#include <linux/random.h>
+
+#include <net/tcp.h>
+#include <net/ndisc.h>
+#include <net/ipv6.h>
+#include <net/transp_v6.h>
+#include <net/addrconf.h>
+#include <net/ip6_route.h>
+#include <net/ip6_checksum.h>
+#include <net/inet_ecn.h>
+#include <net/protocol.h>
+#include <net/xfrm.h>
+#include <net/addrconf.h>
+#include <net/snmp.h>
+#include <net/dsfield.h>
+
+#include <asm/uaccess.h>
+
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+
+static void	tcp_v6_send_reset(struct sk_buff *skb);
+static void	tcp_v6_or_send_ack(struct sk_buff *skb, struct open_request *req);
+static void	tcp_v6_send_check(struct sock *sk, struct tcphdr *th, int len, 
+				  struct sk_buff *skb);
+
+static int	tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb);
+static int	tcp_v6_xmit(struct sk_buff *skb, int ipfragok);
+
+static struct tcp_func ipv6_mapped;
+static struct tcp_func ipv6_specific;
+
+/* I have no idea if this is a good hash for v6 or not. -DaveM */
+static __inline__ int tcp_v6_hashfn(struct in6_addr *laddr, u16 lport,
+				    struct in6_addr *faddr, u16 fport)
+{
+	int hashent = (lport ^ fport);
+
+	hashent ^= (laddr->s6_addr32[3] ^ faddr->s6_addr32[3]);
+	hashent ^= hashent>>16;
+	hashent ^= hashent>>8;
+	return (hashent & (tcp_ehash_size - 1));
+}
+
+static __inline__ int tcp_v6_sk_hashfn(struct sock *sk)
+{
+	struct inet_sock *inet = inet_sk(sk);
+	struct ipv6_pinfo *np = inet6_sk(sk);
+	struct in6_addr *laddr = &np->rcv_saddr;
+	struct in6_addr *faddr = &np->daddr;
+	__u16 lport = inet->num;
+	__u16 fport = inet->dport;
+	return tcp_v6_hashfn(laddr, lport, faddr, fport);
+}
+
+static inline int tcp_v6_bind_conflict(struct sock *sk,
+				       struct tcp_bind_bucket *tb)
+{
+	struct sock *sk2;
+	struct hlist_node *node;
+
+	/* We must walk the whole port owner list in this case. -DaveM */
+	sk_for_each_bound(sk2, node, &tb->owners) {
+		if (sk != sk2 &&
+		    (!sk->sk_bound_dev_if ||
+		     !sk2->sk_bound_dev_if ||
+		     sk->sk_bound_dev_if == sk2->sk_bound_dev_if) &&
+		    (!sk->sk_reuse || !sk2->sk_reuse ||
+		     sk2->sk_state == TCP_LISTEN) &&
+		     ipv6_rcv_saddr_equal(sk, sk2))
+			break;
+	}
+
+	return node != NULL;
+}
+
+/* Grrr, addr_type already calculated by caller, but I don't want
+ * to add some silly "cookie" argument to this method just for that.
+ * But it doesn't matter, the recalculation is in the rarest path
+ * this function ever takes.
+ */
+static int tcp_v6_get_port(struct sock *sk, unsigned short snum)
+{
+	struct tcp_bind_hashbucket *head;
+	struct tcp_bind_bucket *tb;
+	struct hlist_node *node;
+	int ret;
+
+	local_bh_disable();
+	if (snum == 0) {
+		int low = sysctl_local_port_range[0];
+		int high = sysctl_local_port_range[1];
+		int remaining = (high - low) + 1;
+		int rover;
+
+		spin_lock(&tcp_portalloc_lock);
+		rover = tcp_port_rover;
+		do {	rover++;
+			if ((rover < low) || (rover > high))
+				rover = low;
+			head = &tcp_bhash[tcp_bhashfn(rover)];
+			spin_lock(&head->lock);
+			tb_for_each(tb, node, &head->chain)
+				if (tb->port == rover)
+					goto next;
+			break;
+		next:
+			spin_unlock(&head->lock);
+		} while (--remaining > 0);
+		tcp_port_rover = rover;
+		spin_unlock(&tcp_portalloc_lock);
+
+		/* Exhausted local port range during search? */
+		ret = 1;
+		if (remaining <= 0)
+			goto fail;
+
+		/* OK, here is the one we will use. */
+		snum = rover;
+	} else {
+		head = &tcp_bhash[tcp_bhashfn(snum)];
+		spin_lock(&head->lock);
+		tb_for_each(tb, node, &head->chain)
+			if (tb->port == snum)
+				goto tb_found;
+	}
+	tb = NULL;
+	goto tb_not_found;
+tb_found:
+	if (tb && !hlist_empty(&tb->owners)) {
+		if (tb->fastreuse > 0 && sk->sk_reuse &&
+		    sk->sk_state != TCP_LISTEN) {
+			goto success;
+		} else {
+			ret = 1;
+			if (tcp_v6_bind_conflict(sk, tb))
+				goto fail_unlock;
+		}
+	}
+tb_not_found:
+	ret = 1;
+	if (!tb && (tb = tcp_bucket_create(head, snum)) == NULL)
+		goto fail_unlock;
+	if (hlist_empty(&tb->owners)) {
+		if (sk->sk_reuse && sk->sk_state != TCP_LISTEN)
+			tb->fastreuse = 1;
+		else
+			tb->fastreuse = 0;
+	} else if (tb->fastreuse &&
+		   (!sk->sk_reuse || sk->sk_state == TCP_LISTEN))
+		tb->fastreuse = 0;
+
+success:
+	if (!tcp_sk(sk)->bind_hash)
+		tcp_bind_hash(sk, tb, snum);
+	BUG_TRAP(tcp_sk(sk)->bind_hash == tb);
+	ret = 0;
+
+fail_unlock:
+	spin_unlock(&head->lock);
+fail:
+	local_bh_enable();
+	return ret;
+}
+
+static __inline__ void __tcp_v6_hash(struct sock *sk)
+{
+	struct hlist_head *list;
+	rwlock_t *lock;
+
+	BUG_TRAP(sk_unhashed(sk));
+
+	if (sk->sk_state == TCP_LISTEN) {
+		list = &tcp_listening_hash[tcp_sk_listen_hashfn(sk)];
+		lock = &tcp_lhash_lock;
+		tcp_listen_wlock();
+	} else {
+		sk->sk_hashent = tcp_v6_sk_hashfn(sk);
+		list = &tcp_ehash[sk->sk_hashent].chain;
+		lock = &tcp_ehash[sk->sk_hashent].lock;
+		write_lock(lock);
+	}
+
+	__sk_add_node(sk, list);
+	sock_prot_inc_use(sk->sk_prot);
+	write_unlock(lock);
+}
+
+
+static void tcp_v6_hash(struct sock *sk)
+{
+	if (sk->sk_state != TCP_CLOSE) {
+		struct tcp_sock *tp = tcp_sk(sk);
+
+		if (tp->af_specific == &ipv6_mapped) {
+			tcp_prot.hash(sk);
+			return;
+		}
+		local_bh_disable();
+		__tcp_v6_hash(sk);
+		local_bh_enable();
+	}
+}
+
+static struct sock *tcp_v6_lookup_listener(struct in6_addr *daddr, unsigned short hnum, int dif)
+{
+	struct sock *sk;
+	struct hlist_node *node;
+	struct sock *result = NULL;
+	int score, hiscore;
+
+	hiscore=0;
+	read_lock(&tcp_lhash_lock);
+	sk_for_each(sk, node, &tcp_listening_hash[tcp_lhashfn(hnum)]) {
+		if (inet_sk(sk)->num == hnum && sk->sk_family == PF_INET6) {
+			struct ipv6_pinfo *np = inet6_sk(sk);
+			
+			score = 1;
+			if (!ipv6_addr_any(&np->rcv_saddr)) {
+				if (!ipv6_addr_equal(&np->rcv_saddr, daddr))
+					continue;
+				score++;
+			}
+			if (sk->sk_bound_dev_if) {
+				if (sk->sk_bound_dev_if != dif)
+					continue;
+				score++;
+			}
+			if (score == 3) {
+				result = sk;
+				break;
+			}
+			if (score > hiscore) {
+				hiscore = score;
+				result = sk;
+			}
+		}
+	}
+	if (result)
+		sock_hold(result);
+	read_unlock(&tcp_lhash_lock);
+	return result;
+}
+
+/* Sockets in TCP_CLOSE state are _always_ taken out of the hash, so
+ * we need not check it for TCP lookups anymore, thanks Alexey. -DaveM
+ *
+ * The sockhash lock must be held as a reader here.
+ */
+
+static inline struct sock *__tcp_v6_lookup_established(struct in6_addr *saddr, u16 sport,
+						       struct in6_addr *daddr, u16 hnum,
+						       int dif)
+{
+	struct tcp_ehash_bucket *head;
+	struct sock *sk;
+	struct hlist_node *node;
+	__u32 ports = TCP_COMBINED_PORTS(sport, hnum);
+	int hash;
+
+	/* Optimize here for direct hit, only listening connections can
+	 * have wildcards anyways.
+	 */
+	hash = tcp_v6_hashfn(daddr, hnum, saddr, sport);
+	head = &tcp_ehash[hash];
+	read_lock(&head->lock);
+	sk_for_each(sk, node, &head->chain) {
+		/* For IPV6 do the cheaper port and family tests first. */
+		if(TCP_IPV6_MATCH(sk, saddr, daddr, ports, dif))
+			goto hit; /* You sunk my battleship! */
+	}
+	/* Must check for a TIME_WAIT'er before going to listener hash. */
+	sk_for_each(sk, node, &(head + tcp_ehash_size)->chain) {
+		/* FIXME: acme: check this... */
+		struct tcp_tw_bucket *tw = (struct tcp_tw_bucket *)sk;
+
+		if(*((__u32 *)&(tw->tw_dport))	== ports	&&
+		   sk->sk_family		== PF_INET6) {
+			if(ipv6_addr_equal(&tw->tw_v6_daddr, saddr)	&&
+			   ipv6_addr_equal(&tw->tw_v6_rcv_saddr, daddr)	&&
+			   (!sk->sk_bound_dev_if || sk->sk_bound_dev_if == dif))
+				goto hit;
+		}
+	}
+	read_unlock(&head->lock);
+	return NULL;
+
+hit:
+	sock_hold(sk);
+	read_unlock(&head->lock);
+	return sk;
+}
+
+
+static inline struct sock *__tcp_v6_lookup(struct in6_addr *saddr, u16 sport,
+					   struct in6_addr *daddr, u16 hnum,
+					   int dif)
+{
+	struct sock *sk;
+
+	sk = __tcp_v6_lookup_established(saddr, sport, daddr, hnum, dif);
+
+	if (sk)
+		return sk;
+
+	return tcp_v6_lookup_listener(daddr, hnum, dif);
+}
+
+inline struct sock *tcp_v6_lookup(struct in6_addr *saddr, u16 sport,
+				  struct in6_addr *daddr, u16 dport,
+				  int dif)
+{
+	struct sock *sk;
+
+	local_bh_disable();
+	sk = __tcp_v6_lookup(saddr, sport, daddr, ntohs(dport), dif);
+	local_bh_enable();
+
+	return sk;
+}
+
+EXPORT_SYMBOL_GPL(tcp_v6_lookup);
+
+
+/*
+ * Open request hash tables.
+ */
+
+static u32 tcp_v6_synq_hash(struct in6_addr *raddr, u16 rport, u32 rnd)
+{
+	u32 a, b, c;
+
+	a = raddr->s6_addr32[0];
+	b = raddr->s6_addr32[1];
+	c = raddr->s6_addr32[2];
+
+	a += JHASH_GOLDEN_RATIO;
+	b += JHASH_GOLDEN_RATIO;
+	c += rnd;
+	__jhash_mix(a, b, c);
+
+	a += raddr->s6_addr32[3];
+	b += (u32) rport;
+	__jhash_mix(a, b, c);
+
+	return c & (TCP_SYNQ_HSIZE - 1);
+}
+
+static struct open_request *tcp_v6_search_req(struct tcp_sock *tp,
+					      struct open_request ***prevp,
+					      __u16 rport,
+					      struct in6_addr *raddr,
+					      struct in6_addr *laddr,
+					      int iif)
+{
+	struct tcp_listen_opt *lopt = tp->listen_opt;
+	struct open_request *req, **prev;  
+
+	for (prev = &lopt->syn_table[tcp_v6_synq_hash(raddr, rport, lopt->hash_rnd)];
+	     (req = *prev) != NULL;
+	     prev = &req->dl_next) {
+		if (req->rmt_port == rport &&
+		    req->class->family == AF_INET6 &&
+		    ipv6_addr_equal(&req->af.v6_req.rmt_addr, raddr) &&
+		    ipv6_addr_equal(&req->af.v6_req.loc_addr, laddr) &&
+		    (!req->af.v6_req.iif || req->af.v6_req.iif == iif)) {
+			BUG_TRAP(req->sk == NULL);
+			*prevp = prev;
+			return req;
+		}
+	}
+
+	return NULL;
+}
+
+static __inline__ u16 tcp_v6_check(struct tcphdr *th, int len,
+				   struct in6_addr *saddr, 
+				   struct in6_addr *daddr, 
+				   unsigned long base)
+{
+	return csum_ipv6_magic(saddr, daddr, len, IPPROTO_TCP, base);
+}
+
+static __u32 tcp_v6_init_sequence(struct sock *sk, struct sk_buff *skb)
+{
+	if (skb->protocol == htons(ETH_P_IPV6)) {
+		return secure_tcpv6_sequence_number(skb->nh.ipv6h->daddr.s6_addr32,
+						    skb->nh.ipv6h->saddr.s6_addr32,
+						    skb->h.th->dest,
+						    skb->h.th->source);
+	} else {
+		return secure_tcp_sequence_number(skb->nh.iph->daddr,
+						  skb->nh.iph->saddr,
+						  skb->h.th->dest,
+						  skb->h.th->source);
+	}
+}
+
+static int __tcp_v6_check_established(struct sock *sk, __u16 lport,
+				      struct tcp_tw_bucket **twp)
+{
+	struct inet_sock *inet = inet_sk(sk);
+	struct ipv6_pinfo *np = inet6_sk(sk);
+	struct in6_addr *daddr = &np->rcv_saddr;
+	struct in6_addr *saddr = &np->daddr;
+	int dif = sk->sk_bound_dev_if;
+	u32 ports = TCP_COMBINED_PORTS(inet->dport, lport);
+	int hash = tcp_v6_hashfn(daddr, inet->num, saddr, inet->dport);
+	struct tcp_ehash_bucket *head = &tcp_ehash[hash];
+	struct sock *sk2;
+	struct hlist_node *node;
+	struct tcp_tw_bucket *tw;
+
+	write_lock(&head->lock);
+
+	/* Check TIME-WAIT sockets first. */
+	sk_for_each(sk2, node, &(head + tcp_ehash_size)->chain) {
+		tw = (struct tcp_tw_bucket*)sk2;
+
+		if(*((__u32 *)&(tw->tw_dport))	== ports	&&
+		   sk2->sk_family		== PF_INET6	&&
+		   ipv6_addr_equal(&tw->tw_v6_daddr, saddr)	&&
+		   ipv6_addr_equal(&tw->tw_v6_rcv_saddr, daddr)	&&
+		   sk2->sk_bound_dev_if == sk->sk_bound_dev_if) {
+			struct tcp_sock *tp = tcp_sk(sk);
+
+			if (tw->tw_ts_recent_stamp &&
+			    (!twp || (sysctl_tcp_tw_reuse &&
+				      xtime.tv_sec - 
+				      tw->tw_ts_recent_stamp > 1))) {
+				/* See comment in tcp_ipv4.c */
+				tp->write_seq = tw->tw_snd_nxt + 65535 + 2;
+				if (!tp->write_seq)
+					tp->write_seq = 1;
+				tp->rx_opt.ts_recent = tw->tw_ts_recent;
+				tp->rx_opt.ts_recent_stamp = tw->tw_ts_recent_stamp;
+				sock_hold(sk2);
+				goto unique;
+			} else
+				goto not_unique;
+		}
+	}
+	tw = NULL;
+
+	/* And established part... */
+	sk_for_each(sk2, node, &head->chain) {
+		if(TCP_IPV6_MATCH(sk2, saddr, daddr, ports, dif))
+			goto not_unique;
+	}
+
+unique:
+	BUG_TRAP(sk_unhashed(sk));
+	__sk_add_node(sk, &head->chain);
+	sk->sk_hashent = hash;
+	sock_prot_inc_use(sk->sk_prot);
+	write_unlock(&head->lock);
+
+	if (twp) {
+		*twp = tw;
+		NET_INC_STATS_BH(LINUX_MIB_TIMEWAITRECYCLED);
+	} else if (tw) {
+		/* Silly. Should hash-dance instead... */
+		tcp_tw_deschedule(tw);
+		NET_INC_STATS_BH(LINUX_MIB_TIMEWAITRECYCLED);
+
+		tcp_tw_put(tw);
+	}
+	return 0;
+
+not_unique:
+	write_unlock(&head->lock);
+	return -EADDRNOTAVAIL;
+}
+
+static inline u32 tcpv6_port_offset(const struct sock *sk)
+{
+	const struct inet_sock *inet = inet_sk(sk);
+	const struct ipv6_pinfo *np = inet6_sk(sk);
+
+	return secure_tcpv6_port_ephemeral(np->rcv_saddr.s6_addr32,
+					   np->daddr.s6_addr32,
+					   inet->dport);
+}
+
+static int tcp_v6_hash_connect(struct sock *sk)
+{
+	unsigned short snum = inet_sk(sk)->num;
+ 	struct tcp_bind_hashbucket *head;
+ 	struct tcp_bind_bucket *tb;
+	int ret;
+
+ 	if (!snum) {
+ 		int low = sysctl_local_port_range[0];
+ 		int high = sysctl_local_port_range[1];
+		int range = high - low;
+ 		int i;
+		int port;
+		static u32 hint;
+		u32 offset = hint + tcpv6_port_offset(sk);
+		struct hlist_node *node;
+ 		struct tcp_tw_bucket *tw = NULL;
+
+ 		local_bh_disable();
+		for (i = 1; i <= range; i++) {
+			port = low + (i + offset) % range;
+ 			head = &tcp_bhash[tcp_bhashfn(port)];
+ 			spin_lock(&head->lock);
+
+ 			/* Does not bother with rcv_saddr checks,
+ 			 * because the established check is already
+ 			 * unique enough.
+ 			 */
+			tb_for_each(tb, node, &head->chain) {
+ 				if (tb->port == port) {
+ 					BUG_TRAP(!hlist_empty(&tb->owners));
+ 					if (tb->fastreuse >= 0)
+ 						goto next_port;
+ 					if (!__tcp_v6_check_established(sk,
+									port,
+									&tw))
+ 						goto ok;
+ 					goto next_port;
+ 				}
+ 			}
+
+ 			tb = tcp_bucket_create(head, port);
+ 			if (!tb) {
+ 				spin_unlock(&head->lock);
+ 				break;
+ 			}
+ 			tb->fastreuse = -1;
+ 			goto ok;
+
+ 		next_port:
+ 			spin_unlock(&head->lock);
+ 		}
+ 		local_bh_enable();
+
+ 		return -EADDRNOTAVAIL;
+
+ok:
+		hint += i;
+
+ 		/* Head lock still held and bh's disabled */
+ 		tcp_bind_hash(sk, tb, port);
+		if (sk_unhashed(sk)) {
+ 			inet_sk(sk)->sport = htons(port);
+ 			__tcp_v6_hash(sk);
+ 		}
+ 		spin_unlock(&head->lock);
+
+ 		if (tw) {
+ 			tcp_tw_deschedule(tw);
+ 			tcp_tw_put(tw);
+ 		}
+
+		ret = 0;
+		goto out;
+ 	}
+
+ 	head  = &tcp_bhash[tcp_bhashfn(snum)];
+ 	tb  = tcp_sk(sk)->bind_hash;
+	spin_lock_bh(&head->lock);
+
+	if (sk_head(&tb->owners) == sk && !sk->sk_bind_node.next) {
+		__tcp_v6_hash(sk);
+		spin_unlock_bh(&head->lock);
+		return 0;
+	} else {
+		spin_unlock(&head->lock);
+		/* No definite answer... Walk to established hash table */
+		ret = __tcp_v6_check_established(sk, snum, NULL);
+out:
+		local_bh_enable();
+		return ret;
+	}
+}
+
+static __inline__ int tcp_v6_iif(struct sk_buff *skb)
+{
+	return IP6CB(skb)->iif;
+}
+
+static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr, 
+			  int addr_len)
+{
+	struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr;
+	struct inet_sock *inet = inet_sk(sk);
+	struct ipv6_pinfo *np = inet6_sk(sk);
+	struct tcp_sock *tp = tcp_sk(sk);
+	struct in6_addr *saddr = NULL, *final_p = NULL, final;
+	struct flowi fl;
+	struct dst_entry *dst;
+	int addr_type;
+	int err;
+
+	if (addr_len < SIN6_LEN_RFC2133) 
+		return -EINVAL;
+
+	if (usin->sin6_family != AF_INET6) 
+		return(-EAFNOSUPPORT);
+
+	memset(&fl, 0, sizeof(fl));
+
+	if (np->sndflow) {
+		fl.fl6_flowlabel = usin->sin6_flowinfo&IPV6_FLOWINFO_MASK;
+		IP6_ECN_flow_init(fl.fl6_flowlabel);
+		if (fl.fl6_flowlabel&IPV6_FLOWLABEL_MASK) {
+			struct ip6_flowlabel *flowlabel;
+			flowlabel = fl6_sock_lookup(sk, fl.fl6_flowlabel);
+			if (flowlabel == NULL)
+				return -EINVAL;
+			ipv6_addr_copy(&usin->sin6_addr, &flowlabel->dst);
+			fl6_sock_release(flowlabel);
+		}
+	}
+
+	/*
+  	 *	connect() to INADDR_ANY means loopback (BSD'ism).
+  	 */
+  	
+  	if(ipv6_addr_any(&usin->sin6_addr))
+		usin->sin6_addr.s6_addr[15] = 0x1; 
+
+	addr_type = ipv6_addr_type(&usin->sin6_addr);
+
+	if(addr_type & IPV6_ADDR_MULTICAST)
+		return -ENETUNREACH;
+
+	if (addr_type&IPV6_ADDR_LINKLOCAL) {
+		if (addr_len >= sizeof(struct sockaddr_in6) &&
+		    usin->sin6_scope_id) {
+			/* If interface is set while binding, indices
+			 * must coincide.
+			 */
+			if (sk->sk_bound_dev_if &&
+			    sk->sk_bound_dev_if != usin->sin6_scope_id)
+				return -EINVAL;
+
+			sk->sk_bound_dev_if = usin->sin6_scope_id;
+		}
+
+		/* Connect to link-local address requires an interface */
+		if (!sk->sk_bound_dev_if)
+			return -EINVAL;
+	}
+
+	if (tp->rx_opt.ts_recent_stamp &&
+	    !ipv6_addr_equal(&np->daddr, &usin->sin6_addr)) {
+		tp->rx_opt.ts_recent = 0;
+		tp->rx_opt.ts_recent_stamp = 0;
+		tp->write_seq = 0;
+	}
+
+	ipv6_addr_copy(&np->daddr, &usin->sin6_addr);
+	np->flow_label = fl.fl6_flowlabel;
+
+	/*
+	 *	TCP over IPv4
+	 */
+
+	if (addr_type == IPV6_ADDR_MAPPED) {
+		u32 exthdrlen = tp->ext_header_len;
+		struct sockaddr_in sin;
+
+		SOCK_DEBUG(sk, "connect: ipv4 mapped\n");
+
+		if (__ipv6_only_sock(sk))
+			return -ENETUNREACH;
+
+		sin.sin_family = AF_INET;
+		sin.sin_port = usin->sin6_port;
+		sin.sin_addr.s_addr = usin->sin6_addr.s6_addr32[3];
+
+		tp->af_specific = &ipv6_mapped;
+		sk->sk_backlog_rcv = tcp_v4_do_rcv;
+
+		err = tcp_v4_connect(sk, (struct sockaddr *)&sin, sizeof(sin));
+
+		if (err) {
+			tp->ext_header_len = exthdrlen;
+			tp->af_specific = &ipv6_specific;
+			sk->sk_backlog_rcv = tcp_v6_do_rcv;
+			goto failure;
+		} else {
+			ipv6_addr_set(&np->saddr, 0, 0, htonl(0x0000FFFF),
+				      inet->saddr);
+			ipv6_addr_set(&np->rcv_saddr, 0, 0, htonl(0x0000FFFF),
+				      inet->rcv_saddr);
+		}
+
+		return err;
+	}
+
+	if (!ipv6_addr_any(&np->rcv_saddr))
+		saddr = &np->rcv_saddr;
+
+	fl.proto = IPPROTO_TCP;
+	ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
+	ipv6_addr_copy(&fl.fl6_src,
+		       (saddr ? saddr : &np->saddr));
+	fl.oif = sk->sk_bound_dev_if;
+	fl.fl_ip_dport = usin->sin6_port;
+	fl.fl_ip_sport = inet->sport;
+
+	if (np->opt && np->opt->srcrt) {
+		struct rt0_hdr *rt0 = (struct rt0_hdr *)np->opt->srcrt;
+		ipv6_addr_copy(&final, &fl.fl6_dst);
+		ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
+		final_p = &final;
+	}
+
+	err = ip6_dst_lookup(sk, &dst, &fl);
+	if (err)
+		goto failure;
+	if (final_p)
+		ipv6_addr_copy(&fl.fl6_dst, final_p);
+
+	if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0) {
+		dst_release(dst);
+		goto failure;
+	}
+
+	if (saddr == NULL) {
+		saddr = &fl.fl6_src;
+		ipv6_addr_copy(&np->rcv_saddr, saddr);
+	}
+
+	/* set the source address */
+	ipv6_addr_copy(&np->saddr, saddr);
+	inet->rcv_saddr = LOOPBACK4_IPV6;
+
+	ip6_dst_store(sk, dst, NULL);
+	sk->sk_route_caps = dst->dev->features &
+		~(NETIF_F_IP_CSUM | NETIF_F_TSO);
+
+	tp->ext_header_len = 0;
+	if (np->opt)
+		tp->ext_header_len = np->opt->opt_flen + np->opt->opt_nflen;
+
+	tp->rx_opt.mss_clamp = IPV6_MIN_MTU - sizeof(struct tcphdr) - sizeof(struct ipv6hdr);
+
+	inet->dport = usin->sin6_port;
+
+	tcp_set_state(sk, TCP_SYN_SENT);
+	err = tcp_v6_hash_connect(sk);
+	if (err)
+		goto late_failure;
+
+	if (!tp->write_seq)
+		tp->write_seq = secure_tcpv6_sequence_number(np->saddr.s6_addr32,
+							     np->daddr.s6_addr32,
+							     inet->sport,
+							     inet->dport);
+
+	err = tcp_connect(sk);
+	if (err)
+		goto late_failure;
+
+	return 0;
+
+late_failure:
+	tcp_set_state(sk, TCP_CLOSE);
+	__sk_dst_reset(sk);
+failure:
+	inet->dport = 0;
+	sk->sk_route_caps = 0;
+	return err;
+}
+
+static void tcp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
+		int type, int code, int offset, __u32 info)
+{
+	struct ipv6hdr *hdr = (struct ipv6hdr*)skb->data;
+	struct tcphdr *th = (struct tcphdr *)(skb->data+offset);
+	struct ipv6_pinfo *np;
+	struct sock *sk;
+	int err;
+	struct tcp_sock *tp; 
+	__u32 seq;
+
+	sk = tcp_v6_lookup(&hdr->daddr, th->dest, &hdr->saddr, th->source, skb->dev->ifindex);
+
+	if (sk == NULL) {
+		ICMP6_INC_STATS_BH(__in6_dev_get(skb->dev), ICMP6_MIB_INERRORS);
+		return;
+	}
+
+	if (sk->sk_state == TCP_TIME_WAIT) {
+		tcp_tw_put((struct tcp_tw_bucket*)sk);
+		return;
+	}
+
+	bh_lock_sock(sk);
+	if (sock_owned_by_user(sk))
+		NET_INC_STATS_BH(LINUX_MIB_LOCKDROPPEDICMPS);
+
+	if (sk->sk_state == TCP_CLOSE)
+		goto out;
+
+	tp = tcp_sk(sk);
+	seq = ntohl(th->seq); 
+	if (sk->sk_state != TCP_LISTEN &&
+	    !between(seq, tp->snd_una, tp->snd_nxt)) {
+		NET_INC_STATS_BH(LINUX_MIB_OUTOFWINDOWICMPS);
+		goto out;
+	}
+
+	np = inet6_sk(sk);
+
+	if (type == ICMPV6_PKT_TOOBIG) {
+		struct dst_entry *dst = NULL;
+
+		if (sock_owned_by_user(sk))
+			goto out;
+		if ((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE))
+			goto out;
+
+		/* icmp should have updated the destination cache entry */
+		dst = __sk_dst_check(sk, np->dst_cookie);
+
+		if (dst == NULL) {
+			struct inet_sock *inet = inet_sk(sk);
+			struct flowi fl;
+
+			/* BUGGG_FUTURE: Again, it is not clear how
+			   to handle rthdr case. Ignore this complexity
+			   for now.
+			 */
+			memset(&fl, 0, sizeof(fl));
+			fl.proto = IPPROTO_TCP;
+			ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
+			ipv6_addr_copy(&fl.fl6_src, &np->saddr);
+			fl.oif = sk->sk_bound_dev_if;
+			fl.fl_ip_dport = inet->dport;
+			fl.fl_ip_sport = inet->sport;
+
+			if ((err = ip6_dst_lookup(sk, &dst, &fl))) {
+				sk->sk_err_soft = -err;
+				goto out;
+			}
+
+			if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0) {
+				sk->sk_err_soft = -err;
+				goto out;
+			}
+
+		} else
+			dst_hold(dst);
+
+		if (tp->pmtu_cookie > dst_mtu(dst)) {
+			tcp_sync_mss(sk, dst_mtu(dst));
+			tcp_simple_retransmit(sk);
+		} /* else let the usual retransmit timer handle it */
+		dst_release(dst);
+		goto out;
+	}
+
+	icmpv6_err_convert(type, code, &err);
+
+	/* Might be for an open_request */
+	switch (sk->sk_state) {
+		struct open_request *req, **prev;
+	case TCP_LISTEN:
+		if (sock_owned_by_user(sk))
+			goto out;
+
+		req = tcp_v6_search_req(tp, &prev, th->dest, &hdr->daddr,
+					&hdr->saddr, tcp_v6_iif(skb));
+		if (!req)
+			goto out;
+
+		/* ICMPs are not backlogged, hence we cannot get
+		 * an established socket here.
+		 */
+		BUG_TRAP(req->sk == NULL);
+
+		if (seq != req->snt_isn) {
+			NET_INC_STATS_BH(LINUX_MIB_OUTOFWINDOWICMPS);
+			goto out;
+		}
+
+		tcp_synq_drop(sk, req, prev);
+		goto out;
+
+	case TCP_SYN_SENT:
+	case TCP_SYN_RECV:  /* Cannot happen.
+			       It can, it SYNs are crossed. --ANK */ 
+		if (!sock_owned_by_user(sk)) {
+			TCP_INC_STATS_BH(TCP_MIB_ATTEMPTFAILS);
+			sk->sk_err = err;
+			sk->sk_error_report(sk);		/* Wake people up to see the error (see connect in sock.c) */
+
+			tcp_done(sk);
+		} else
+			sk->sk_err_soft = err;
+		goto out;
+	}
+
+	if (!sock_owned_by_user(sk) && np->recverr) {
+		sk->sk_err = err;
+		sk->sk_error_report(sk);
+	} else
+		sk->sk_err_soft = err;
+
+out:
+	bh_unlock_sock(sk);
+	sock_put(sk);
+}
+
+
+static int tcp_v6_send_synack(struct sock *sk, struct open_request *req,
+			      struct dst_entry *dst)
+{
+	struct ipv6_pinfo *np = inet6_sk(sk);
+	struct sk_buff * skb;
+	struct ipv6_txoptions *opt = NULL;
+	struct in6_addr * final_p = NULL, final;
+	struct flowi fl;
+	int err = -1;
+
+	memset(&fl, 0, sizeof(fl));
+	fl.proto = IPPROTO_TCP;
+	ipv6_addr_copy(&fl.fl6_dst, &req->af.v6_req.rmt_addr);
+	ipv6_addr_copy(&fl.fl6_src, &req->af.v6_req.loc_addr);
+	fl.fl6_flowlabel = 0;
+	fl.oif = req->af.v6_req.iif;
+	fl.fl_ip_dport = req->rmt_port;
+	fl.fl_ip_sport = inet_sk(sk)->sport;
+
+	if (dst == NULL) {
+		opt = np->opt;
+		if (opt == NULL &&
+		    np->rxopt.bits.srcrt == 2 &&
+		    req->af.v6_req.pktopts) {
+			struct sk_buff *pktopts = req->af.v6_req.pktopts;
+			struct inet6_skb_parm *rxopt = IP6CB(pktopts);
+			if (rxopt->srcrt)
+				opt = ipv6_invert_rthdr(sk, (struct ipv6_rt_hdr*)(pktopts->nh.raw + rxopt->srcrt));
+		}
+
+		if (opt && opt->srcrt) {
+			struct rt0_hdr *rt0 = (struct rt0_hdr *) opt->srcrt;
+			ipv6_addr_copy(&final, &fl.fl6_dst);
+			ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
+			final_p = &final;
+		}
+
+		err = ip6_dst_lookup(sk, &dst, &fl);
+		if (err)
+			goto done;
+		if (final_p)
+			ipv6_addr_copy(&fl.fl6_dst, final_p);
+		if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0)
+			goto done;
+	}
+
+	skb = tcp_make_synack(sk, dst, req);
+	if (skb) {
+		struct tcphdr *th = skb->h.th;
+
+		th->check = tcp_v6_check(th, skb->len,
+					 &req->af.v6_req.loc_addr, &req->af.v6_req.rmt_addr,
+					 csum_partial((char *)th, skb->len, skb->csum));
+
+		ipv6_addr_copy(&fl.fl6_dst, &req->af.v6_req.rmt_addr);
+		err = ip6_xmit(sk, skb, &fl, opt, 0);
+		if (err == NET_XMIT_CN)
+			err = 0;
+	}
+
+done:
+	dst_release(dst);
+        if (opt && opt != np->opt)
+		sock_kfree_s(sk, opt, opt->tot_len);
+	return err;
+}
+
+static void tcp_v6_or_free(struct open_request *req)
+{
+	if (req->af.v6_req.pktopts)
+		kfree_skb(req->af.v6_req.pktopts);
+}
+
+static struct or_calltable or_ipv6 = {
+	.family		=	AF_INET6,
+	.rtx_syn_ack	=	tcp_v6_send_synack,
+	.send_ack	=	tcp_v6_or_send_ack,
+	.destructor	=	tcp_v6_or_free,
+	.send_reset	=	tcp_v6_send_reset
+};
+
+static int ipv6_opt_accepted(struct sock *sk, struct sk_buff *skb)
+{
+	struct ipv6_pinfo *np = inet6_sk(sk);
+	struct inet6_skb_parm *opt = IP6CB(skb);
+
+	if (np->rxopt.all) {
+		if ((opt->hop && np->rxopt.bits.hopopts) ||
+		    ((IPV6_FLOWINFO_MASK&*(u32*)skb->nh.raw) &&
+		     np->rxopt.bits.rxflow) ||
+		    (opt->srcrt && np->rxopt.bits.srcrt) ||
+		    ((opt->dst1 || opt->dst0) && np->rxopt.bits.dstopts))
+			return 1;
+	}
+	return 0;
+}
+
+
+static void tcp_v6_send_check(struct sock *sk, struct tcphdr *th, int len, 
+			      struct sk_buff *skb)
+{
+	struct ipv6_pinfo *np = inet6_sk(sk);
+
+	if (skb->ip_summed == CHECKSUM_HW) {
+		th->check = ~csum_ipv6_magic(&np->saddr, &np->daddr, len, IPPROTO_TCP,  0);
+		skb->csum = offsetof(struct tcphdr, check);
+	} else {
+		th->check = csum_ipv6_magic(&np->saddr, &np->daddr, len, IPPROTO_TCP, 
+					    csum_partial((char *)th, th->doff<<2, 
+							 skb->csum));
+	}
+}
+
+
+static void tcp_v6_send_reset(struct sk_buff *skb)
+{
+	struct tcphdr *th = skb->h.th, *t1; 
+	struct sk_buff *buff;
+	struct flowi fl;
+
+	if (th->rst)
+		return;
+
+	if (!ipv6_unicast_destination(skb))
+		return; 
+
+	/*
+	 * We need to grab some memory, and put together an RST,
+	 * and then put it into the queue to be sent.
+	 */
+
+	buff = alloc_skb(MAX_HEADER + sizeof(struct ipv6hdr) + sizeof(struct tcphdr),
+			 GFP_ATOMIC);
+	if (buff == NULL) 
+	  	return;
+
+	skb_reserve(buff, MAX_HEADER + sizeof(struct ipv6hdr) + sizeof(struct tcphdr));
+
+	t1 = (struct tcphdr *) skb_push(buff,sizeof(struct tcphdr));
+
+	/* Swap the send and the receive. */
+	memset(t1, 0, sizeof(*t1));
+	t1->dest = th->source;
+	t1->source = th->dest;
+	t1->doff = sizeof(*t1)/4;
+	t1->rst = 1;
+  
+	if(th->ack) {
+	  	t1->seq = th->ack_seq;
+	} else {
+		t1->ack = 1;
+		t1->ack_seq = htonl(ntohl(th->seq) + th->syn + th->fin
+				    + skb->len - (th->doff<<2));
+	}
+
+	buff->csum = csum_partial((char *)t1, sizeof(*t1), 0);
+
+	memset(&fl, 0, sizeof(fl));
+	ipv6_addr_copy(&fl.fl6_dst, &skb->nh.ipv6h->saddr);
+	ipv6_addr_copy(&fl.fl6_src, &skb->nh.ipv6h->daddr);
+
+	t1->check = csum_ipv6_magic(&fl.fl6_src, &fl.fl6_dst,
+				    sizeof(*t1), IPPROTO_TCP,
+				    buff->csum);
+
+	fl.proto = IPPROTO_TCP;
+	fl.oif = tcp_v6_iif(skb);
+	fl.fl_ip_dport = t1->dest;
+	fl.fl_ip_sport = t1->source;
+
+	/* sk = NULL, but it is safe for now. RST socket required. */
+	if (!ip6_dst_lookup(NULL, &buff->dst, &fl)) {
+
+		if ((xfrm_lookup(&buff->dst, &fl, NULL, 0)) < 0) {
+			dst_release(buff->dst);
+			return;
+		}
+
+		ip6_xmit(NULL, buff, &fl, NULL, 0);
+		TCP_INC_STATS_BH(TCP_MIB_OUTSEGS);
+		TCP_INC_STATS_BH(TCP_MIB_OUTRSTS);
+		return;
+	}
+
+	kfree_skb(buff);
+}
+
+static void tcp_v6_send_ack(struct sk_buff *skb, u32 seq, u32 ack, u32 win, u32 ts)
+{
+	struct tcphdr *th = skb->h.th, *t1;
+	struct sk_buff *buff;
+	struct flowi fl;
+	int tot_len = sizeof(struct tcphdr);
+
+	if (ts)
+		tot_len += 3*4;
+
+	buff = alloc_skb(MAX_HEADER + sizeof(struct ipv6hdr) + tot_len,
+			 GFP_ATOMIC);
+	if (buff == NULL)
+		return;
+
+	skb_reserve(buff, MAX_HEADER + sizeof(struct ipv6hdr) + tot_len);
+
+	t1 = (struct tcphdr *) skb_push(buff,tot_len);
+
+	/* Swap the send and the receive. */
+	memset(t1, 0, sizeof(*t1));
+	t1->dest = th->source;
+	t1->source = th->dest;
+	t1->doff = tot_len/4;
+	t1->seq = htonl(seq);
+	t1->ack_seq = htonl(ack);
+	t1->ack = 1;
+	t1->window = htons(win);
+	
+	if (ts) {
+		u32 *ptr = (u32*)(t1 + 1);
+		*ptr++ = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) |
+			       (TCPOPT_TIMESTAMP << 8) | TCPOLEN_TIMESTAMP);
+		*ptr++ = htonl(tcp_time_stamp);
+		*ptr = htonl(ts);
+	}
+
+	buff->csum = csum_partial((char *)t1, tot_len, 0);
+
+	memset(&fl, 0, sizeof(fl));
+	ipv6_addr_copy(&fl.fl6_dst, &skb->nh.ipv6h->saddr);
+	ipv6_addr_copy(&fl.fl6_src, &skb->nh.ipv6h->daddr);
+
+	t1->check = csum_ipv6_magic(&fl.fl6_src, &fl.fl6_dst,
+				    tot_len, IPPROTO_TCP,
+				    buff->csum);
+
+	fl.proto = IPPROTO_TCP;
+	fl.oif = tcp_v6_iif(skb);
+	fl.fl_ip_dport = t1->dest;
+	fl.fl_ip_sport = t1->source;
+
+	if (!ip6_dst_lookup(NULL, &buff->dst, &fl)) {
+		if ((xfrm_lookup(&buff->dst, &fl, NULL, 0)) < 0) {
+			dst_release(buff->dst);
+			return;
+		}
+		ip6_xmit(NULL, buff, &fl, NULL, 0);
+		TCP_INC_STATS_BH(TCP_MIB_OUTSEGS);
+		return;
+	}
+
+	kfree_skb(buff);
+}
+
+static void tcp_v6_timewait_ack(struct sock *sk, struct sk_buff *skb)
+{
+	struct tcp_tw_bucket *tw = (struct tcp_tw_bucket *)sk;
+
+	tcp_v6_send_ack(skb, tw->tw_snd_nxt, tw->tw_rcv_nxt,
+			tw->tw_rcv_wnd >> tw->tw_rcv_wscale, tw->tw_ts_recent);
+
+	tcp_tw_put(tw);
+}
+
+static void tcp_v6_or_send_ack(struct sk_buff *skb, struct open_request *req)
+{
+	tcp_v6_send_ack(skb, req->snt_isn+1, req->rcv_isn+1, req->rcv_wnd, req->ts_recent);
+}
+
+
+static struct sock *tcp_v6_hnd_req(struct sock *sk,struct sk_buff *skb)
+{
+	struct open_request *req, **prev;
+	struct tcphdr *th = skb->h.th;
+	struct tcp_sock *tp = tcp_sk(sk);
+	struct sock *nsk;
+
+	/* Find possible connection requests. */
+	req = tcp_v6_search_req(tp, &prev, th->source, &skb->nh.ipv6h->saddr,
+				&skb->nh.ipv6h->daddr, tcp_v6_iif(skb));
+	if (req)
+		return tcp_check_req(sk, skb, req, prev);
+
+	nsk = __tcp_v6_lookup_established(&skb->nh.ipv6h->saddr,
+					  th->source,
+					  &skb->nh.ipv6h->daddr,
+					  ntohs(th->dest),
+					  tcp_v6_iif(skb));
+
+	if (nsk) {
+		if (nsk->sk_state != TCP_TIME_WAIT) {
+			bh_lock_sock(nsk);
+			return nsk;
+		}
+		tcp_tw_put((struct tcp_tw_bucket*)nsk);
+		return NULL;
+	}
+
+#if 0 /*def CONFIG_SYN_COOKIES*/
+	if (!th->rst && !th->syn && th->ack)
+		sk = cookie_v6_check(sk, skb, &(IPCB(skb)->opt));
+#endif
+	return sk;
+}
+
+static void tcp_v6_synq_add(struct sock *sk, struct open_request *req)
+{
+	struct tcp_sock *tp = tcp_sk(sk);
+	struct tcp_listen_opt *lopt = tp->listen_opt;
+	u32 h = tcp_v6_synq_hash(&req->af.v6_req.rmt_addr, req->rmt_port, lopt->hash_rnd);
+
+	req->sk = NULL;
+	req->expires = jiffies + TCP_TIMEOUT_INIT;
+	req->retrans = 0;
+	req->dl_next = lopt->syn_table[h];
+
+	write_lock(&tp->syn_wait_lock);
+	lopt->syn_table[h] = req;
+	write_unlock(&tp->syn_wait_lock);
+
+	tcp_synq_added(sk);
+}
+
+
+/* FIXME: this is substantially similar to the ipv4 code.
+ * Can some kind of merge be done? -- erics
+ */
+static int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
+{
+	struct ipv6_pinfo *np = inet6_sk(sk);
+	struct tcp_options_received tmp_opt;
+	struct tcp_sock *tp = tcp_sk(sk);
+	struct open_request *req = NULL;
+	__u32 isn = TCP_SKB_CB(skb)->when;
+
+	if (skb->protocol == htons(ETH_P_IP))
+		return tcp_v4_conn_request(sk, skb);
+
+	if (!ipv6_unicast_destination(skb))
+		goto drop; 
+
+	/*
+	 *	There are no SYN attacks on IPv6, yet...	
+	 */
+	if (tcp_synq_is_full(sk) && !isn) {
+		if (net_ratelimit())
+			printk(KERN_INFO "TCPv6: dropping request, synflood is possible\n");
+		goto drop;		
+	}
+
+	if (sk_acceptq_is_full(sk) && tcp_synq_young(sk) > 1)
+		goto drop;
+
+	req = tcp_openreq_alloc();
+	if (req == NULL)
+		goto drop;
+
+	tcp_clear_options(&tmp_opt);
+	tmp_opt.mss_clamp = IPV6_MIN_MTU - sizeof(struct tcphdr) - sizeof(struct ipv6hdr);
+	tmp_opt.user_mss = tp->rx_opt.user_mss;
+
+	tcp_parse_options(skb, &tmp_opt, 0);
+
+	tmp_opt.tstamp_ok = tmp_opt.saw_tstamp;
+	tcp_openreq_init(req, &tmp_opt, skb);
+
+	req->class = &or_ipv6;
+	ipv6_addr_copy(&req->af.v6_req.rmt_addr, &skb->nh.ipv6h->saddr);
+	ipv6_addr_copy(&req->af.v6_req.loc_addr, &skb->nh.ipv6h->daddr);
+	TCP_ECN_create_request(req, skb->h.th);
+	req->af.v6_req.pktopts = NULL;
+	if (ipv6_opt_accepted(sk, skb) ||
+	    np->rxopt.bits.rxinfo ||
+	    np->rxopt.bits.rxhlim) {
+		atomic_inc(&skb->users);
+		req->af.v6_req.pktopts = skb;
+	}
+	req->af.v6_req.iif = sk->sk_bound_dev_if;
+
+	/* So that link locals have meaning */
+	if (!sk->sk_bound_dev_if &&
+	    ipv6_addr_type(&req->af.v6_req.rmt_addr) & IPV6_ADDR_LINKLOCAL)
+		req->af.v6_req.iif = tcp_v6_iif(skb);
+
+	if (isn == 0) 
+		isn = tcp_v6_init_sequence(sk,skb);
+
+	req->snt_isn = isn;
+
+	if (tcp_v6_send_synack(sk, req, NULL))
+		goto drop;
+
+	tcp_v6_synq_add(sk, req);
+
+	return 0;
+
+drop:
+	if (req)
+		tcp_openreq_free(req);
+
+	TCP_INC_STATS_BH(TCP_MIB_ATTEMPTFAILS);
+	return 0; /* don't send reset */
+}
+
+static struct sock * tcp_v6_syn_recv_sock(struct sock *sk, struct sk_buff *skb,
+					  struct open_request *req,
+					  struct dst_entry *dst)
+{
+	struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
+	struct tcp6_sock *newtcp6sk;
+	struct inet_sock *newinet;
+	struct tcp_sock *newtp;
+	struct sock *newsk;
+	struct ipv6_txoptions *opt;
+
+	if (skb->protocol == htons(ETH_P_IP)) {
+		/*
+		 *	v6 mapped
+		 */
+
+		newsk = tcp_v4_syn_recv_sock(sk, skb, req, dst);
+
+		if (newsk == NULL) 
+			return NULL;
+
+		newtcp6sk = (struct tcp6_sock *)newsk;
+		inet_sk(newsk)->pinet6 = &newtcp6sk->inet6;
+
+		newinet = inet_sk(newsk);
+		newnp = inet6_sk(newsk);
+		newtp = tcp_sk(newsk);
+
+		memcpy(newnp, np, sizeof(struct ipv6_pinfo));
+
+		ipv6_addr_set(&newnp->daddr, 0, 0, htonl(0x0000FFFF),
+			      newinet->daddr);
+
+		ipv6_addr_set(&newnp->saddr, 0, 0, htonl(0x0000FFFF),
+			      newinet->saddr);
+
+		ipv6_addr_copy(&newnp->rcv_saddr, &newnp->saddr);
+
+		newtp->af_specific = &ipv6_mapped;
+		newsk->sk_backlog_rcv = tcp_v4_do_rcv;
+		newnp->pktoptions  = NULL;
+		newnp->opt	   = NULL;
+		newnp->mcast_oif   = tcp_v6_iif(skb);
+		newnp->mcast_hops  = skb->nh.ipv6h->hop_limit;
+
+		/* Charge newly allocated IPv6 socket. Though it is mapped,
+		 * it is IPv6 yet.
+		 */
+#ifdef INET_REFCNT_DEBUG
+		atomic_inc(&inet6_sock_nr);
+#endif
+
+		/* It is tricky place. Until this moment IPv4 tcp
+		   worked with IPv6 af_tcp.af_specific.
+		   Sync it now.
+		 */
+		tcp_sync_mss(newsk, newtp->pmtu_cookie);
+
+		return newsk;
+	}
+
+	opt = np->opt;
+
+	if (sk_acceptq_is_full(sk))
+		goto out_overflow;
+
+	if (np->rxopt.bits.srcrt == 2 &&
+	    opt == NULL && req->af.v6_req.pktopts) {
+		struct inet6_skb_parm *rxopt = IP6CB(req->af.v6_req.pktopts);
+		if (rxopt->srcrt)
+			opt = ipv6_invert_rthdr(sk, (struct ipv6_rt_hdr*)(req->af.v6_req.pktopts->nh.raw+rxopt->srcrt));
+	}
+
+	if (dst == NULL) {
+		struct in6_addr *final_p = NULL, final;
+		struct flowi fl;
+
+		memset(&fl, 0, sizeof(fl));
+		fl.proto = IPPROTO_TCP;
+		ipv6_addr_copy(&fl.fl6_dst, &req->af.v6_req.rmt_addr);
+		if (opt && opt->srcrt) {
+			struct rt0_hdr *rt0 = (struct rt0_hdr *) opt->srcrt;
+			ipv6_addr_copy(&final, &fl.fl6_dst);
+			ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
+			final_p = &final;
+		}
+		ipv6_addr_copy(&fl.fl6_src, &req->af.v6_req.loc_addr);
+		fl.oif = sk->sk_bound_dev_if;
+		fl.fl_ip_dport = req->rmt_port;
+		fl.fl_ip_sport = inet_sk(sk)->sport;
+
+		if (ip6_dst_lookup(sk, &dst, &fl))
+			goto out;
+
+		if (final_p)
+			ipv6_addr_copy(&fl.fl6_dst, final_p);
+
+		if ((xfrm_lookup(&dst, &fl, sk, 0)) < 0)
+			goto out;
+	} 
+
+	newsk = tcp_create_openreq_child(sk, req, skb);
+	if (newsk == NULL)
+		goto out;
+
+	/* Charge newly allocated IPv6 socket */
+#ifdef INET_REFCNT_DEBUG
+	atomic_inc(&inet6_sock_nr);
+#endif
+
+	ip6_dst_store(newsk, dst, NULL);
+	newsk->sk_route_caps = dst->dev->features &
+		~(NETIF_F_IP_CSUM | NETIF_F_TSO);
+
+	newtcp6sk = (struct tcp6_sock *)newsk;
+	inet_sk(newsk)->pinet6 = &newtcp6sk->inet6;
+
+	newtp = tcp_sk(newsk);
+	newinet = inet_sk(newsk);
+	newnp = inet6_sk(newsk);
+
+	memcpy(newnp, np, sizeof(struct ipv6_pinfo));
+
+	ipv6_addr_copy(&newnp->daddr, &req->af.v6_req.rmt_addr);
+	ipv6_addr_copy(&newnp->saddr, &req->af.v6_req.loc_addr);
+	ipv6_addr_copy(&newnp->rcv_saddr, &req->af.v6_req.loc_addr);
+	newsk->sk_bound_dev_if = req->af.v6_req.iif;
+
+	/* Now IPv6 options... 
+
+	   First: no IPv4 options.
+	 */
+	newinet->opt = NULL;
+
+	/* Clone RX bits */
+	newnp->rxopt.all = np->rxopt.all;
+
+	/* Clone pktoptions received with SYN */
+	newnp->pktoptions = NULL;
+	if (req->af.v6_req.pktopts) {
+		newnp->pktoptions = skb_clone(req->af.v6_req.pktopts,
+					      GFP_ATOMIC);
+		kfree_skb(req->af.v6_req.pktopts);
+		req->af.v6_req.pktopts = NULL;
+		if (newnp->pktoptions)
+			skb_set_owner_r(newnp->pktoptions, newsk);
+	}
+	newnp->opt	  = NULL;
+	newnp->mcast_oif  = tcp_v6_iif(skb);
+	newnp->mcast_hops = skb->nh.ipv6h->hop_limit;
+
+	/* Clone native IPv6 options from listening socket (if any)
+
+	   Yes, keeping reference count would be much more clever,
+	   but we make one more one thing there: reattach optmem
+	   to newsk.
+	 */
+	if (opt) {
+		newnp->opt = ipv6_dup_options(newsk, opt);
+		if (opt != np->opt)
+			sock_kfree_s(sk, opt, opt->tot_len);
+	}
+
+	newtp->ext_header_len = 0;
+	if (newnp->opt)
+		newtp->ext_header_len = newnp->opt->opt_nflen +
+					newnp->opt->opt_flen;
+
+	tcp_sync_mss(newsk, dst_mtu(dst));
+	newtp->advmss = dst_metric(dst, RTAX_ADVMSS);
+	tcp_initialize_rcv_mss(newsk);
+
+	newinet->daddr = newinet->saddr = newinet->rcv_saddr = LOOPBACK4_IPV6;
+
+	__tcp_v6_hash(newsk);
+	tcp_inherit_port(sk, newsk);
+
+	return newsk;
+
+out_overflow:
+	NET_INC_STATS_BH(LINUX_MIB_LISTENOVERFLOWS);
+out:
+	NET_INC_STATS_BH(LINUX_MIB_LISTENDROPS);
+	if (opt && opt != np->opt)
+		sock_kfree_s(sk, opt, opt->tot_len);
+	dst_release(dst);
+	return NULL;
+}
+
+static int tcp_v6_checksum_init(struct sk_buff *skb)
+{
+	if (skb->ip_summed == CHECKSUM_HW) {
+		skb->ip_summed = CHECKSUM_UNNECESSARY;
+		if (!tcp_v6_check(skb->h.th,skb->len,&skb->nh.ipv6h->saddr,
+				  &skb->nh.ipv6h->daddr,skb->csum))
+			return 0;
+		LIMIT_NETDEBUG(printk(KERN_DEBUG "hw tcp v6 csum failed\n"));
+	}
+	if (skb->len <= 76) {
+		if (tcp_v6_check(skb->h.th,skb->len,&skb->nh.ipv6h->saddr,
+				 &skb->nh.ipv6h->daddr,skb_checksum(skb, 0, skb->len, 0)))
+			return -1;
+		skb->ip_summed = CHECKSUM_UNNECESSARY;
+	} else {
+		skb->csum = ~tcp_v6_check(skb->h.th,skb->len,&skb->nh.ipv6h->saddr,
+					  &skb->nh.ipv6h->daddr,0);
+	}
+	return 0;
+}
+
+/* The socket must have it's spinlock held when we get
+ * here.
+ *
+ * We have a potential double-lock case here, so even when
+ * doing backlog processing we use the BH locking scheme.
+ * This is because we cannot sleep with the original spinlock
+ * held.
+ */
+static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
+{
+	struct ipv6_pinfo *np = inet6_sk(sk);
+	struct tcp_sock *tp;
+	struct sk_buff *opt_skb = NULL;
+
+	/* Imagine: socket is IPv6. IPv4 packet arrives,
+	   goes to IPv4 receive handler and backlogged.
+	   From backlog it always goes here. Kerboom...
+	   Fortunately, tcp_rcv_established and rcv_established
+	   handle them correctly, but it is not case with
+	   tcp_v6_hnd_req and tcp_v6_send_reset().   --ANK
+	 */
+
+	if (skb->protocol == htons(ETH_P_IP))
+		return tcp_v4_do_rcv(sk, skb);
+
+	if (sk_filter(sk, skb, 0))
+		goto discard;
+
+	/*
+	 *	socket locking is here for SMP purposes as backlog rcv
+	 *	is currently called with bh processing disabled.
+	 */
+
+	/* Do Stevens' IPV6_PKTOPTIONS.
+
+	   Yes, guys, it is the only place in our code, where we
+	   may make it not affecting IPv4.
+	   The rest of code is protocol independent,
+	   and I do not like idea to uglify IPv4.
+
+	   Actually, all the idea behind IPV6_PKTOPTIONS
+	   looks not very well thought. For now we latch
+	   options, received in the last packet, enqueued
+	   by tcp. Feel free to propose better solution.
+	                                       --ANK (980728)
+	 */
+	if (np->rxopt.all)
+		opt_skb = skb_clone(skb, GFP_ATOMIC);
+
+	if (sk->sk_state == TCP_ESTABLISHED) { /* Fast path */
+		TCP_CHECK_TIMER(sk);
+		if (tcp_rcv_established(sk, skb, skb->h.th, skb->len))
+			goto reset;
+		TCP_CHECK_TIMER(sk);
+		if (opt_skb)
+			goto ipv6_pktoptions;
+		return 0;
+	}
+
+	if (skb->len < (skb->h.th->doff<<2) || tcp_checksum_complete(skb))
+		goto csum_err;
+
+	if (sk->sk_state == TCP_LISTEN) { 
+		struct sock *nsk = tcp_v6_hnd_req(sk, skb);
+		if (!nsk)
+			goto discard;
+
+		/*
+		 * Queue it on the new socket if the new socket is active,
+		 * otherwise we just shortcircuit this and continue with
+		 * the new socket..
+		 */
+ 		if(nsk != sk) {
+			if (tcp_child_process(sk, nsk, skb))
+				goto reset;
+			if (opt_skb)
+				__kfree_skb(opt_skb);
+			return 0;
+		}
+	}
+
+	TCP_CHECK_TIMER(sk);
+	if (tcp_rcv_state_process(sk, skb, skb->h.th, skb->len))
+		goto reset;
+	TCP_CHECK_TIMER(sk);
+	if (opt_skb)
+		goto ipv6_pktoptions;
+	return 0;
+
+reset:
+	tcp_v6_send_reset(skb);
+discard:
+	if (opt_skb)
+		__kfree_skb(opt_skb);
+	kfree_skb(skb);
+	return 0;
+csum_err:
+	TCP_INC_STATS_BH(TCP_MIB_INERRS);
+	goto discard;
+
+
+ipv6_pktoptions:
+	/* Do you ask, what is it?
+
+	   1. skb was enqueued by tcp.
+	   2. skb is added to tail of read queue, rather than out of order.
+	   3. socket is not in passive state.
+	   4. Finally, it really contains options, which user wants to receive.
+	 */
+	tp = tcp_sk(sk);
+	if (TCP_SKB_CB(opt_skb)->end_seq == tp->rcv_nxt &&
+	    !((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN))) {
+		if (np->rxopt.bits.rxinfo)
+			np->mcast_oif = tcp_v6_iif(opt_skb);
+		if (np->rxopt.bits.rxhlim)
+			np->mcast_hops = opt_skb->nh.ipv6h->hop_limit;
+		if (ipv6_opt_accepted(sk, opt_skb)) {
+			skb_set_owner_r(opt_skb, sk);
+			opt_skb = xchg(&np->pktoptions, opt_skb);
+		} else {
+			__kfree_skb(opt_skb);
+			opt_skb = xchg(&np->pktoptions, NULL);
+		}
+	}
+
+	if (opt_skb)
+		kfree_skb(opt_skb);
+	return 0;
+}
+
+static int tcp_v6_rcv(struct sk_buff **pskb, unsigned int *nhoffp)
+{
+	struct sk_buff *skb = *pskb;
+	struct tcphdr *th;	
+	struct sock *sk;
+	int ret;
+
+	if (skb->pkt_type != PACKET_HOST)
+		goto discard_it;
+
+	/*
+	 *	Count it even if it's bad.
+	 */
+	TCP_INC_STATS_BH(TCP_MIB_INSEGS);
+
+	if (!pskb_may_pull(skb, sizeof(struct tcphdr)))
+		goto discard_it;
+
+	th = skb->h.th;
+
+	if (th->doff < sizeof(struct tcphdr)/4)
+		goto bad_packet;
+	if (!pskb_may_pull(skb, th->doff*4))
+		goto discard_it;
+
+	if ((skb->ip_summed != CHECKSUM_UNNECESSARY &&
+	     tcp_v6_checksum_init(skb) < 0))
+		goto bad_packet;
+
+	th = skb->h.th;
+	TCP_SKB_CB(skb)->seq = ntohl(th->seq);
+	TCP_SKB_CB(skb)->end_seq = (TCP_SKB_CB(skb)->seq + th->syn + th->fin +
+				    skb->len - th->doff*4);
+	TCP_SKB_CB(skb)->ack_seq = ntohl(th->ack_seq);
+	TCP_SKB_CB(skb)->when = 0;
+	TCP_SKB_CB(skb)->flags = ipv6_get_dsfield(skb->nh.ipv6h);
+	TCP_SKB_CB(skb)->sacked = 0;
+
+	sk = __tcp_v6_lookup(&skb->nh.ipv6h->saddr, th->source,
+			     &skb->nh.ipv6h->daddr, ntohs(th->dest), tcp_v6_iif(skb));
+
+	if (!sk)
+		goto no_tcp_socket;
+
+process:
+	if (sk->sk_state == TCP_TIME_WAIT)
+		goto do_time_wait;
+
+	if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
+		goto discard_and_relse;
+
+	if (sk_filter(sk, skb, 0))
+		goto discard_and_relse;
+
+	skb->dev = NULL;
+
+	bh_lock_sock(sk);
+	ret = 0;
+	if (!sock_owned_by_user(sk)) {
+		if (!tcp_prequeue(sk, skb))
+			ret = tcp_v6_do_rcv(sk, skb);
+	} else
+		sk_add_backlog(sk, skb);
+	bh_unlock_sock(sk);
+
+	sock_put(sk);
+	return ret ? -1 : 0;
+
+no_tcp_socket:
+	if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
+		goto discard_it;
+
+	if (skb->len < (th->doff<<2) || tcp_checksum_complete(skb)) {
+bad_packet:
+		TCP_INC_STATS_BH(TCP_MIB_INERRS);
+	} else {
+		tcp_v6_send_reset(skb);
+	}
+
+discard_it:
+
+	/*
+	 *	Discard frame
+	 */
+
+	kfree_skb(skb);
+	return 0;
+
+discard_and_relse:
+	sock_put(sk);
+	goto discard_it;
+
+do_time_wait:
+	if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
+		tcp_tw_put((struct tcp_tw_bucket *) sk);
+		goto discard_it;
+	}
+
+	if (skb->len < (th->doff<<2) || tcp_checksum_complete(skb)) {
+		TCP_INC_STATS_BH(TCP_MIB_INERRS);
+		tcp_tw_put((struct tcp_tw_bucket *) sk);
+		goto discard_it;
+	}
+
+	switch(tcp_timewait_state_process((struct tcp_tw_bucket *)sk,
+					  skb, th, skb->len)) {
+	case TCP_TW_SYN:
+	{
+		struct sock *sk2;
+
+		sk2 = tcp_v6_lookup_listener(&skb->nh.ipv6h->daddr, ntohs(th->dest), tcp_v6_iif(skb));
+		if (sk2 != NULL) {
+			tcp_tw_deschedule((struct tcp_tw_bucket *)sk);
+			tcp_tw_put((struct tcp_tw_bucket *)sk);
+			sk = sk2;
+			goto process;
+		}
+		/* Fall through to ACK */
+	}
+	case TCP_TW_ACK:
+		tcp_v6_timewait_ack(sk, skb);
+		break;
+	case TCP_TW_RST:
+		goto no_tcp_socket;
+	case TCP_TW_SUCCESS:;
+	}
+	goto discard_it;
+}
+
+static int tcp_v6_rebuild_header(struct sock *sk)
+{
+	int err;
+	struct dst_entry *dst;
+	struct ipv6_pinfo *np = inet6_sk(sk);
+
+	dst = __sk_dst_check(sk, np->dst_cookie);
+
+	if (dst == NULL) {
+		struct inet_sock *inet = inet_sk(sk);
+		struct in6_addr *final_p = NULL, final;
+		struct flowi fl;
+
+		memset(&fl, 0, sizeof(fl));
+		fl.proto = IPPROTO_TCP;
+		ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
+		ipv6_addr_copy(&fl.fl6_src, &np->saddr);
+		fl.fl6_flowlabel = np->flow_label;
+		fl.oif = sk->sk_bound_dev_if;
+		fl.fl_ip_dport = inet->dport;
+		fl.fl_ip_sport = inet->sport;
+
+		if (np->opt && np->opt->srcrt) {
+			struct rt0_hdr *rt0 = (struct rt0_hdr *) np->opt->srcrt;
+			ipv6_addr_copy(&final, &fl.fl6_dst);
+			ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
+			final_p = &final;
+		}
+
+		err = ip6_dst_lookup(sk, &dst, &fl);
+		if (err) {
+			sk->sk_route_caps = 0;
+			return err;
+		}
+		if (final_p)
+			ipv6_addr_copy(&fl.fl6_dst, final_p);
+
+		if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0) {
+			sk->sk_err_soft = -err;
+			dst_release(dst);
+			return err;
+		}
+
+		ip6_dst_store(sk, dst, NULL);
+		sk->sk_route_caps = dst->dev->features &
+			~(NETIF_F_IP_CSUM | NETIF_F_TSO);
+	}
+
+	return 0;
+}
+
+static int tcp_v6_xmit(struct sk_buff *skb, int ipfragok)
+{
+	struct sock *sk = skb->sk;
+	struct inet_sock *inet = inet_sk(sk);
+	struct ipv6_pinfo *np = inet6_sk(sk);
+	struct flowi fl;
+	struct dst_entry *dst;
+	struct in6_addr *final_p = NULL, final;
+
+	memset(&fl, 0, sizeof(fl));
+	fl.proto = IPPROTO_TCP;
+	ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
+	ipv6_addr_copy(&fl.fl6_src, &np->saddr);
+	fl.fl6_flowlabel = np->flow_label;
+	IP6_ECN_flow_xmit(sk, fl.fl6_flowlabel);
+	fl.oif = sk->sk_bound_dev_if;
+	fl.fl_ip_sport = inet->sport;
+	fl.fl_ip_dport = inet->dport;
+
+	if (np->opt && np->opt->srcrt) {
+		struct rt0_hdr *rt0 = (struct rt0_hdr *) np->opt->srcrt;
+		ipv6_addr_copy(&final, &fl.fl6_dst);
+		ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
+		final_p = &final;
+	}
+
+	dst = __sk_dst_check(sk, np->dst_cookie);
+
+	if (dst == NULL) {
+		int err = ip6_dst_lookup(sk, &dst, &fl);
+
+		if (err) {
+			sk->sk_err_soft = -err;
+			return err;
+		}
+
+		if (final_p)
+			ipv6_addr_copy(&fl.fl6_dst, final_p);
+
+		if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0) {
+			sk->sk_route_caps = 0;
+			dst_release(dst);
+			return err;
+		}
+
+		ip6_dst_store(sk, dst, NULL);
+		sk->sk_route_caps = dst->dev->features &
+			~(NETIF_F_IP_CSUM | NETIF_F_TSO);
+	}
+
+	skb->dst = dst_clone(dst);
+
+	/* Restore final destination back after routing done */
+	ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
+
+	return ip6_xmit(sk, skb, &fl, np->opt, 0);
+}
+
+static void v6_addr2sockaddr(struct sock *sk, struct sockaddr * uaddr)
+{
+	struct ipv6_pinfo *np = inet6_sk(sk);
+	struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *) uaddr;
+
+	sin6->sin6_family = AF_INET6;
+	ipv6_addr_copy(&sin6->sin6_addr, &np->daddr);
+	sin6->sin6_port	= inet_sk(sk)->dport;
+	/* We do not store received flowlabel for TCP */
+	sin6->sin6_flowinfo = 0;
+	sin6->sin6_scope_id = 0;
+	if (sk->sk_bound_dev_if &&
+	    ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
+		sin6->sin6_scope_id = sk->sk_bound_dev_if;
+}
+
+static int tcp_v6_remember_stamp(struct sock *sk)
+{
+	/* Alas, not yet... */
+	return 0;
+}
+
+static struct tcp_func ipv6_specific = {
+	.queue_xmit	=	tcp_v6_xmit,
+	.send_check	=	tcp_v6_send_check,
+	.rebuild_header	=	tcp_v6_rebuild_header,
+	.conn_request	=	tcp_v6_conn_request,
+	.syn_recv_sock	=	tcp_v6_syn_recv_sock,
+	.remember_stamp	=	tcp_v6_remember_stamp,
+	.net_header_len	=	sizeof(struct ipv6hdr),
+
+	.setsockopt	=	ipv6_setsockopt,
+	.getsockopt	=	ipv6_getsockopt,
+	.addr2sockaddr	=	v6_addr2sockaddr,
+	.sockaddr_len	=	sizeof(struct sockaddr_in6)
+};
+
+/*
+ *	TCP over IPv4 via INET6 API
+ */
+
+static struct tcp_func ipv6_mapped = {
+	.queue_xmit	=	ip_queue_xmit,
+	.send_check	=	tcp_v4_send_check,
+	.rebuild_header	=	tcp_v4_rebuild_header,
+	.conn_request	=	tcp_v6_conn_request,
+	.syn_recv_sock	=	tcp_v6_syn_recv_sock,
+	.remember_stamp	=	tcp_v4_remember_stamp,
+	.net_header_len	=	sizeof(struct iphdr),
+
+	.setsockopt	=	ipv6_setsockopt,
+	.getsockopt	=	ipv6_getsockopt,
+	.addr2sockaddr	=	v6_addr2sockaddr,
+	.sockaddr_len	=	sizeof(struct sockaddr_in6)
+};
+
+
+
+/* NOTE: A lot of things set to zero explicitly by call to
+ *       sk_alloc() so need not be done here.
+ */
+static int tcp_v6_init_sock(struct sock *sk)
+{
+	struct tcp_sock *tp = tcp_sk(sk);
+
+	skb_queue_head_init(&tp->out_of_order_queue);
+	tcp_init_xmit_timers(sk);
+	tcp_prequeue_init(tp);
+
+	tp->rto  = TCP_TIMEOUT_INIT;
+	tp->mdev = TCP_TIMEOUT_INIT;
+
+	/* So many TCP implementations out there (incorrectly) count the
+	 * initial SYN frame in their delayed-ACK and congestion control
+	 * algorithms that we must have the following bandaid to talk
+	 * efficiently to them.  -DaveM
+	 */
+	tp->snd_cwnd = 2;
+
+	/* See draft-stevens-tcpca-spec-01 for discussion of the
+	 * initialization of these values.
+	 */
+	tp->snd_ssthresh = 0x7fffffff;
+	tp->snd_cwnd_clamp = ~0;
+	tp->mss_cache_std = tp->mss_cache = 536;
+
+	tp->reordering = sysctl_tcp_reordering;
+
+	sk->sk_state = TCP_CLOSE;
+
+	tp->af_specific = &ipv6_specific;
+
+	sk->sk_write_space = sk_stream_write_space;
+	sock_set_flag(sk, SOCK_USE_WRITE_QUEUE);
+
+	sk->sk_sndbuf = sysctl_tcp_wmem[1];
+	sk->sk_rcvbuf = sysctl_tcp_rmem[1];
+
+	atomic_inc(&tcp_sockets_allocated);
+
+	return 0;
+}
+
+static int tcp_v6_destroy_sock(struct sock *sk)
+{
+	extern int tcp_v4_destroy_sock(struct sock *sk);
+
+	tcp_v4_destroy_sock(sk);
+	return inet6_destroy_sock(sk);
+}
+
+/* Proc filesystem TCPv6 sock list dumping. */
+static void get_openreq6(struct seq_file *seq, 
+			 struct sock *sk, struct open_request *req, int i, int uid)
+{
+	struct in6_addr *dest, *src;
+	int ttd = req->expires - jiffies;
+
+	if (ttd < 0)
+		ttd = 0;
+
+	src = &req->af.v6_req.loc_addr;
+	dest = &req->af.v6_req.rmt_addr;
+	seq_printf(seq,
+		   "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
+		   "%02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %p\n",
+		   i,
+		   src->s6_addr32[0], src->s6_addr32[1],
+		   src->s6_addr32[2], src->s6_addr32[3],
+		   ntohs(inet_sk(sk)->sport),
+		   dest->s6_addr32[0], dest->s6_addr32[1],
+		   dest->s6_addr32[2], dest->s6_addr32[3],
+		   ntohs(req->rmt_port),
+		   TCP_SYN_RECV,
+		   0,0, /* could print option size, but that is af dependent. */
+		   1,   /* timers active (only the expire timer) */  
+		   jiffies_to_clock_t(ttd), 
+		   req->retrans,
+		   uid,
+		   0,  /* non standard timer */  
+		   0, /* open_requests have no inode */
+		   0, req);
+}
+
+static void get_tcp6_sock(struct seq_file *seq, struct sock *sp, int i)
+{
+	struct in6_addr *dest, *src;
+	__u16 destp, srcp;
+	int timer_active;
+	unsigned long timer_expires;
+	struct inet_sock *inet = inet_sk(sp);
+	struct tcp_sock *tp = tcp_sk(sp);
+	struct ipv6_pinfo *np = inet6_sk(sp);
+
+	dest  = &np->daddr;
+	src   = &np->rcv_saddr;
+	destp = ntohs(inet->dport);
+	srcp  = ntohs(inet->sport);
+	if (tp->pending == TCP_TIME_RETRANS) {
+		timer_active	= 1;
+		timer_expires	= tp->timeout;
+	} else if (tp->pending == TCP_TIME_PROBE0) {
+		timer_active	= 4;
+		timer_expires	= tp->timeout;
+	} else if (timer_pending(&sp->sk_timer)) {
+		timer_active	= 2;
+		timer_expires	= sp->sk_timer.expires;
+	} else {
+		timer_active	= 0;
+		timer_expires = jiffies;
+	}
+
+	seq_printf(seq,
+		   "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
+		   "%02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %p %u %u %u %u %d\n",
+		   i,
+		   src->s6_addr32[0], src->s6_addr32[1],
+		   src->s6_addr32[2], src->s6_addr32[3], srcp,
+		   dest->s6_addr32[0], dest->s6_addr32[1],
+		   dest->s6_addr32[2], dest->s6_addr32[3], destp,
+		   sp->sk_state, 
+		   tp->write_seq-tp->snd_una, tp->rcv_nxt-tp->copied_seq,
+		   timer_active,
+		   jiffies_to_clock_t(timer_expires - jiffies),
+		   tp->retransmits,
+		   sock_i_uid(sp),
+		   tp->probes_out,
+		   sock_i_ino(sp),
+		   atomic_read(&sp->sk_refcnt), sp,
+		   tp->rto, tp->ack.ato, (tp->ack.quick<<1)|tp->ack.pingpong,
+		   tp->snd_cwnd, tp->snd_ssthresh>=0xFFFF?-1:tp->snd_ssthresh
+		   );
+}
+
+static void get_timewait6_sock(struct seq_file *seq, 
+			       struct tcp_tw_bucket *tw, int i)
+{
+	struct in6_addr *dest, *src;
+	__u16 destp, srcp;
+	int ttd = tw->tw_ttd - jiffies;
+
+	if (ttd < 0)
+		ttd = 0;
+
+	dest  = &tw->tw_v6_daddr;
+	src   = &tw->tw_v6_rcv_saddr;
+	destp = ntohs(tw->tw_dport);
+	srcp  = ntohs(tw->tw_sport);
+
+	seq_printf(seq,
+		   "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
+		   "%02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %p\n",
+		   i,
+		   src->s6_addr32[0], src->s6_addr32[1],
+		   src->s6_addr32[2], src->s6_addr32[3], srcp,
+		   dest->s6_addr32[0], dest->s6_addr32[1],
+		   dest->s6_addr32[2], dest->s6_addr32[3], destp,
+		   tw->tw_substate, 0, 0,
+		   3, jiffies_to_clock_t(ttd), 0, 0, 0, 0,
+		   atomic_read(&tw->tw_refcnt), tw);
+}
+
+#ifdef CONFIG_PROC_FS
+static int tcp6_seq_show(struct seq_file *seq, void *v)
+{
+	struct tcp_iter_state *st;
+
+	if (v == SEQ_START_TOKEN) {
+		seq_puts(seq,
+			 "  sl  "
+			 "local_address                         "
+			 "remote_address                        "
+			 "st tx_queue rx_queue tr tm->when retrnsmt"
+			 "   uid  timeout inode\n");
+		goto out;
+	}
+	st = seq->private;
+
+	switch (st->state) {
+	case TCP_SEQ_STATE_LISTENING:
+	case TCP_SEQ_STATE_ESTABLISHED:
+		get_tcp6_sock(seq, v, st->num);
+		break;
+	case TCP_SEQ_STATE_OPENREQ:
+		get_openreq6(seq, st->syn_wait_sk, v, st->num, st->uid);
+		break;
+	case TCP_SEQ_STATE_TIME_WAIT:
+		get_timewait6_sock(seq, v, st->num);
+		break;
+	}
+out:
+	return 0;
+}
+
+static struct file_operations tcp6_seq_fops;
+static struct tcp_seq_afinfo tcp6_seq_afinfo = {
+	.owner		= THIS_MODULE,
+	.name		= "tcp6",
+	.family		= AF_INET6,
+	.seq_show	= tcp6_seq_show,
+	.seq_fops	= &tcp6_seq_fops,
+};
+
+int __init tcp6_proc_init(void)
+{
+	return tcp_proc_register(&tcp6_seq_afinfo);
+}
+
+void tcp6_proc_exit(void)
+{
+	tcp_proc_unregister(&tcp6_seq_afinfo);
+}
+#endif
+
+struct proto tcpv6_prot = {
+	.name			= "TCPv6",
+	.owner			= THIS_MODULE,
+	.close			= tcp_close,
+	.connect		= tcp_v6_connect,
+	.disconnect		= tcp_disconnect,
+	.accept			= tcp_accept,
+	.ioctl			= tcp_ioctl,
+	.init			= tcp_v6_init_sock,
+	.destroy		= tcp_v6_destroy_sock,
+	.shutdown		= tcp_shutdown,
+	.setsockopt		= tcp_setsockopt,
+	.getsockopt		= tcp_getsockopt,
+	.sendmsg		= tcp_sendmsg,
+	.recvmsg		= tcp_recvmsg,
+	.backlog_rcv		= tcp_v6_do_rcv,
+	.hash			= tcp_v6_hash,
+	.unhash			= tcp_unhash,
+	.get_port		= tcp_v6_get_port,
+	.enter_memory_pressure	= tcp_enter_memory_pressure,
+	.sockets_allocated	= &tcp_sockets_allocated,
+	.memory_allocated	= &tcp_memory_allocated,
+	.memory_pressure	= &tcp_memory_pressure,
+	.sysctl_mem		= sysctl_tcp_mem,
+	.sysctl_wmem		= sysctl_tcp_wmem,
+	.sysctl_rmem		= sysctl_tcp_rmem,
+	.max_header		= MAX_TCP_HEADER,
+	.obj_size		= sizeof(struct tcp6_sock),
+};
+
+static struct inet6_protocol tcpv6_protocol = {
+	.handler	=	tcp_v6_rcv,
+	.err_handler	=	tcp_v6_err,
+	.flags		=	INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
+};
+
+extern struct proto_ops inet6_stream_ops;
+
+static struct inet_protosw tcpv6_protosw = {
+	.type		=	SOCK_STREAM,
+	.protocol	=	IPPROTO_TCP,
+	.prot		=	&tcpv6_prot,
+	.ops		=	&inet6_stream_ops,
+	.capability	=	-1,
+	.no_check	=	0,
+	.flags		=	INET_PROTOSW_PERMANENT,
+};
+
+void __init tcpv6_init(void)
+{
+	/* register inet6 protocol */
+	if (inet6_add_protocol(&tcpv6_protocol, IPPROTO_TCP) < 0)
+		printk(KERN_ERR "tcpv6_init: Could not register protocol\n");
+	inet6_register_protosw(&tcpv6_protosw);
+}